650-RICR-20-05-2
650-RICR-20-05-2. RICRMP: Ocean SAMP - Chapter 2 - Ecology (version Technical Revision, 03/08/2012 to 08/17/2018)
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 1 of 132
Chapter 2: Ecology of the Ocean SAMP Region
Table of Contents
List of Figures................................................................................................................................ 3
List of Tables ................................................................................................................................. 5
200. Introduction........................................................................................................................... 6
210. Geological Oceanography .................................................................................................. 12
220. Meteorology......................................................................................................................... 20
220.1. Wind .............................................................................................................................. 20
220.2.
Storms........................................................................................................................ 22
230. Physical Oceanography ...................................................................................................... 24
230.1. Waves............................................................................................................................. 27
230.2. Tides and Tidal Processes............................................................................................ 27
230.3. Hydrography................................................................................................................. 30
230.3.1. Temperature........................................................................................................... 30
230.3.2. Salinity.................................................................................................................... 33
230.3.3. Stratification........................................................................................................... 35
230.4. Circulation .................................................................................................................... 39
230.4.1. Block Island Sound................................................................................................ 41
230.4.2. Rhode Island Sound .............................................................................................. 43
240. Chemical Oceanography .................................................................................................... 47
240.1. Nutrients........................................................................................................................ 47
240.2. Toxins ............................................................................................................................ 49
250. Biological Oceanography.................................................................................................... 53
250.1. Plankton ........................................................................................................................ 53
250.1.1. Phytoplankton Productivity.................................................................................. 54
250.1.2. Phytoplankton Seasonality.................................................................................... 57
250.1.3. Zooplankton ........................................................................................................... 59
250.1.4. Microbes ................................................................................................................. 61
250.1.5. Fish and Invertebrate Eggs and Larvae.............................................................. 62
250.1.6. Harmful Algal Blooms........................................................................................... 66
250.2. Benthic Ecosystem........................................................................................................ 69
250.2.1. Invertebrates.......................................................................................................... 66
250.2.1.1. Block Island Sound............................................................................................. 66
250.2.1.2. Rhode Island Sound ........................................................................................... 66
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 2 of 132
250.3. Fishes ............................................................................................................................. 79
250.4. Marine Mammals......................................................................................................... 66
250.4.1. Cetaceans................................................................................................................ 66
250.4.2. Pinnipeds ................................................................................................................ 66
250.5. Sea Turtles .................................................................................................................... 66
250.6. Avifauna........................................................................................................................ 66
260. Emerging Issues ............................................................................................................... 66
260.1.
Native Species Explosions ........................................................................................ 66
260.2.
Invasive species ......................................................................................................... 66
260.3.
Marine Diseases ........................................................................................................ 66
270. Policies and Standards........................................................................................................ 66
270.1 General Policies ............................................................................................................. 66
270.2 Regulatory Standards ................................................................................................... 66
280. Literature Cited .................................................................................................................. 66
Appendix I. Siting Analysis- Ecological Value Map………………………………….……..131
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 3 of 132
List of Figures
Figure 2.1. General geographic layout, basic bathymetry, and major features of the Ocean SAMP
area.................................................................................................................................................. 7
Figure 2.2. Approximate location of major glacial lakes and direction of drainage flows........... 13
Figure 2.3. Location of glacial moraines in the Ocean SAMP area. ............................................ 15
Figure 2.4. Bottom characteristics in a section of Rhode Island Sound. ...................................... 18
Figure 2.5. Average annual, average maximum, and average minimum wind speeds over the
Ocean SAMP area......................................................................................................................... 21
Figure 2.6. Hurricane tracks where the eye moved over Rhode Island........................................ 22
Figure 2.7. Northern cold water currents, southern warm water currents, and Gulf Stream warm
core rings entering the Ocean SAMP area.................................................................................... 26
Figure 2.8. Water current velocities in Block Island Sound......................................................... 29
Figure 2.9. MARMAP water temperature data for all stations located within the Ocean SAMP
area................................................................................................................................................ 31
Figure 2.10. Seasonal water temperatures at sea surface, 20 m depth, and seafloor in the Ocean
SAMP area.................................................................................................................................... 32
Figure 2.11. Average annual surface and bottom temperatures in Block Island Sound............... 33
Figure 2.12. Seasonal water salinities at various depths in the Ocean SAMP area...................... 34
Figure 2.13. Average annual surface and bottom salinity at a station in Block Island Sound ..... 37
Figure 2.14. Surface water salinity. .............................................................................................. 37
Figure 2.15. Differences in tidal circulation velocities between Rhode Island Sound (RIS) and
Block Island Sound (BIS)............................................................................................................. 39
Figure 2.16. Hypothesized water flow at surface and at depth in the Ocean SAMP area ............ 40
Figure 2.17. Summary of currents and hydrography in the Ocean SAMP area ......................... 412
Figure 2.18. Seasonal volume transport from Block Island Sound into Long Island Sound........ 42
Figure 2.19. Probability of sea surface temperatures occurring along the “front” ..................... 434
Figure 2.20. Seasonal, tidally averaged volume transport between Narragansett Bay and Rhode
Island Sound.................................................................................................................................. 45
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 4 of 132
Figure 2.21. Dredged materials disposal sites, and location of the North Cape oil spill.............. 51
Figure 2.22. Monthly averaged chlorophyll a concentrations in the Ocean SAMP area ............. 59
Figure 2.23. Ichthyoplankton abundance at the mouth of Narragansett Bay/Rhode Island Sound
....................................................................................................................................................... 64
Figure 2.24. Lobster larval transport from the edge of the Continental Shelf into Rhode Island
Sound and Block Island Sound..................................................................................................... 65
Figure 2.25. Benthic geological environments in a select portion of Block Island Sound........... 66
Figure 2.26. Benthic surface roughness in the Ocean SAMP area............................................... 66
Figure 2.27. Seasonal composition of major fish and invertebrate species in the Ocean SAMP
area................................................................................................................................................ 66
Figure 2.28. Trawl catches at Whale Rock................................................................................... 66
Figure 2.29. Rate of increase/decrease of species collected at Whale Rock ................................ 66
Figure 2.30. Annual mean abundance of nine species collected at Whale Rock.......................... 66
Figure 2.31. Community metrics for long term trawl samples collected at Whale Rock............. 66
Figure 2.32. Modeled seasonal relative abundance patterns of right whales, humpback whales,
and fin whales in the Ocean SAMP area, ..................................................................................... 66
Figure 2.33. Modeled seasonal relative abundance patterns of harbor porpoise, common dolphin,
and Atlantic white-sided dolphin in the Ocean SAMP area ......................................................... 66
Figure 2.34. Harbor seal haul-out sites......................................................................................... 66
Figure 2.35. Modeled seasonal relative abundance patterns of leatherback sea turtles in the
Ocean SAMP area......................................................................................................................... 66
Figure 2.36. Seasonality of avifauna in the Ocean SAMP area.................................................... 66
Figure 2.37. Potential use of the Ocean SAMP area by diving ducks.......................................... 66
Figure 2. 38. Seasonal use of the Ocean SAMP area by gulls, loons and shearwaters ................ 66
Figure 2.39. Most abundant waterbirds nearshore and offshore in the Ocean SAMP area.......... 66
Figure 2.40. Framework for Ecological Valuation Mapping as applied to the Ocean SAMP…113
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 5 of 132
List of Tables
Table 2.1. Nutrient concentrations measured in Block Island Sound........................................... 49
Table 2.2. Nutrient concentrations measured in Rhode Island Sound.......................................... 49
Table 2.3. Comparison of primary production in Ocean SAMP waters with nearby ecosystems 56
Table 2.4. MARMAP Ocean SAMP area zooplankton data collected since 1978....................... 61
Table 2.5. Seasonality of fish eggs and larvae in Block Island Sound......................................... 66
Table 2.6. MARMAP ichthyoplankton data collected since 1978 ............................................... 66
Table 2.7. First approximation of species preferences for habitats in the Ocean SAMP area...... 66
Table 2.8. Percent occurrence of species landed in trawls taken in Block Island Sound............. 66
Table 2.9. Percent biomass of species landed in trawls taken in Block Island Sound.................. 66
Table 2.10. The occurance of marine mammals and sea turtles in Continental Shelf waters ...... 66
Table 2.11. Common songbirds utilizing Block Island. ............................................................... 66
Table 2.12. Avifauna of the Ocean SAMP area............................................................................ 66
Table 2.13. Listing of invasive and potentially invasive marine species...................................... 66
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 6 of 132
Section 200. Introduction
1. The term “ecology,” translated from its Greek origins, literally means “the study of
home.” From this, ecology can be thought of as a description, based on information
gleaned and gathered during various studies, of the place where something resides.
Ecology incorporates study not just of living things—the biota—but also non-living
elements—the abiotic resources—because they profoundly influence where and how the
living organisms exist. Ecology attempts to understand and describe the interactions
between various living organisms with each other, between living organisms and the non-
living resources existing in the local environment, and between the various abiotic
components of the ecosystem.
2. While ecological study can be performed at various scales in the environment, this
chapter will generally attempt to provide description at an ecosystem scale, though that
description may be based on a subset of smaller patches of environment with the
ecosystem. An ecosystem is defined as the collection of the various ecological
communities, which are comprised of the populations of different species living in the
area, and the non-living resources upon which they depend. For the purposes of this
chapter, the ecosystem being described is that of the Ocean Special Area Management
Plan (SAMP) region, the boundaries of which are shown in Figure 2.1.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 7 of 132
Figure 2.1. General geographic layout, basic bathymetry, and major features of the Ocean SAMP area as discussed in this chapter.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 8 of 132
3. The Ocean SAMP region is a busy maritime entryway to Narragansett Bay, Long Island
Sound, Buzzards Bay and the Cape Cod Canal. It could be anticipated that much would
be known about the ecology, biology and ecological functioning of this important region.
To date, mainly small-scale areas of the sea floor and water column have been intensively
studied in Rhode Island Sound, Block Island Sound or the Offshore Ocean SAMP area
(the region immediately south of Rhode Island Sound and Block Island Sound, roughly
that area south of Block Island to the Continental Shelf Slope, is considered here to be the
Offshore Ocean SAMP area, and will be referred to as such throughout this chapter).
Therefore understanding of the overall ecology of this ecosystem is somewhat
fragmented.
4. The Ocean SAMP area is an ecologically unique region—the Rhode Island Sound and
Block Island Sound ecosystems are located at the boundary of two intermingling
biogeographic provinces, the Acadian to the north (Cape Cod to the Gulf of Maine) and
the Virginian to the south (Cape Cod to Cape Hatteras). Because of this, the Ocean
SAMP area contains an interesting biodiversity that is a mix of northern, cold water
species and more southern, warm water species.
5. Unfortunately, there is no baseline of information for the area that pre-dates human
disturbances such as trawl fishing, so scientists have been and are investigating a changed
ecosystem. New studies, however, are underway by a variety of researchers sponsored by
various agencies and institutions. This chapter takes the patchwork of available
information and attempts to stitch it together into a coherent fabric that describes the
basic ecology of the overall Ocean SAMP area. The chapter should be updated from time
to time to reflect the findings of new research.
6. The Ocean SAMP area includes Rhode Island Sound and the central and eastern portions
of Block Island Sound, both of which are shallow, nearshore continental shelf waters
lying between Martha’s Vineyard/Elizabeth Islands, and Long Island. The area is
dynamically connected to Narragansett Bay, Buzzards Bay, Long Island Sound, and the
Atlantic Ocean via the Continental Shelf. Long Island Sound is a significant influence on
the physical oceanography of the area due to the input of low salinity water from several
major rivers (e.g., Connecticut River). A shallow sill extends from Montauk Point to
Block Island at a depth of 15–25 meters, and partially isolates Block Island Sound from
the Continental Shelf acting to some degree as a buffer to wave impacts. A canyon—
Block Channel—extends several tens of kilometers from the deepest point of the sill,
forming a deep connection between Block Island Sound and the Offshore Ocean SAMP
area region of the Atlantic Ocean. The area of Rhode Island Sound and Block Island
Sound overlapping the Ocean SAMP area is approximately 3,800 km2.
7. Located in a temperate climate, the waters of the Ocean SAMP area are highly seasonal.
Winter water temperatures, at both surface and bottom, range from 3–6°C and from 10–
21°C during summer. During winter, bottom waters are often warmer, by several degrees,
than surface waters, while in summer this trend is reversed with bottom water often 10°C
colder than surface water. The disparity between surface and bottom water temperatures
are important to the physical structure of the water column—summer conditions tend to
promote stratification while winter conditions have a destabilizing effect that breaks
down stratification. Water column stratification, a naturally occurring event in Ocean
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 9 of 132
SAMP area waters, reduces interaction between surface waters and the rest of the water
column. Stratification often sets up physical conditions that concentrates food items and
draws in marine life, becoming a “hot spot” of biological activity. In warm, shallow
areas, stratification can sometimes lead to reduced oxygen concentrations in bottom
waters, creating stressful conditions. Anoxia or hypoxia (no or little dissolved oxygen)
are not reported for waters in the Ocean SAMP area.
8. With a direct, open connection to the Atlantic Ocean, salinity in the Ocean SAMP area
has varying, small ranges, with lowest values in spring and summer as influenced by
spring rains and melting snow pack. While these ranges are small, they can be important
in driving circulation, assisting in the development and stability of stratification, and
influencing the marine life inhabiting the region. The dynamic physical oceanography of
the area sets up zones where sharp differences in temperature and/or salinity between
inshore and shelf water create discontinuities, called fronts. These fronts, which occur
mainly during summer along the Offshore Ocean SAMP area, and in a region just south
of Block Island, provide unique biological and/or physical characteristics that cause them
to be major fish attraction areas.
9. The Ocean SAMP area is a biologically productive area, comparable to though slightly
less so than nearby waters, such as Long Island Sound and Nantucket Sound. The growth
of phytoplankton is seasonal, with spring and fall generally being the most productive
times of year. Species composition of phytoplankton in the Ocean SAMP area reflects its
interactions with Narragansett Bay, Long Island Sound and the Continental Shelf regions.
Like Narragansett Bay, the annual winter–spring bloom of phytoplankton in Rhode Island
Sound appears to be becoming less consistent in its regularity. Zooplankton populations
are also seasonal, generally following the trends of phytoplankton abundance. Species
composition and seasonality of zooplankton abundances does not appear to have changed
much over the past 50 or so years for dominant species. Shifts towards smaller species of
copepods in Continental Shelf waters has been documented, but it is not clear if this trend
is being mimicked in Ocean SAMP waters.
10. Juvenile fish and eggs (e.g., ichthyoplankton) in the Ocean SAMP area are rich and
varied, and show strong seasonality for many species, which is most often linked to
reproduction. The seasonality of some ichthyoplankton appears to be changing over time,
but the data are too sparse to say this with any degree of surety. For adult fishes however,
the pattern is clearer. The fish community of Ocean SAMP waters is dynamic and
diverse, but has undergone major change over the recent past. Demersal, or bottom
dwelling fishes such as winter flounder, once were the dominant fish types of the area.
Since the mid-1970s there has been a shift towards pelagic fish species dominance, with a
corresponding increase in bottom invertebrates such as crabs and lobster. Dominant fish
species are now bluefish, butterfish, and sea robins, at the expense of winter flounder and
hake, for example. Squid, a large pelagic invertebrate, has also increased in abundance as
this shift from demersal fish species ensued. Similar change is being noted throughout the
broader North Atlantic region, and appears to be correlated to warming water
temperatures resulting from changing climate.
11. The organisms living in the sediments make up an important food source for demersal
fishes, and play a critical role in the cycling of organic material. The benthic communities
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 10 of 132
in the Ocean SAMP area are dominated by various species of amphipods, with tube
dwelling species (e.g., ampeliscids) being the most dominant throughout the area.
Bivalves, marine worms, and small shrimps make up the bulk of the remaining dominant
benthic species. There appears to be correlation between the types of sediments making
up the bottom and the species that occur in them, but there is not enough information at
hand to map this in any meaningful way, or to make species–bottom type correlations
with any degree of surety.
12. Marine mammals—whales, dolphins, porpoise and seals—utilize the Ocean SAMP area,
but sparsely and generally on a seasonal basis. While whales will often venture into
Ocean SAMP waters, they are not resident and generally are passing through; most whale
sightings occur in deeper waters out over the Continental Shelf. Harbor seals do utilize
Ocean SAMP waters during winter months, and a growing North Atlantic population of
this species makes them a regular sight from late fall to early spring before the seals
move north to breed. Gray seals are less common to the area, though increasing
populations of this species is resulting in increased visitation as well. Sea turtles too are
often sighted in Ocean SAMP waters, but most are traveling through the area and as such
are considered occasional visitors.
13. Bird life throughout the Ocean SAMP area is varied, with waterbirds being the most
abundant. Passerines utilize Ocean SAMP air space during migration periods, and Block
Island is an important stop over and resting spot for many species. Use of Ocean SAMP
waters by waterbirds is heaviest during winter months, with a peak from early March
through mid-April. Water of less than 20 m in depth is important feeding habitat for
diving ducks, and nearshore shallow waters are important feeding habitat for terns
nesting onshore during summer months.
14. A major issue of concern for the overall ecology of the Ocean SAMP area is changing
climate. Changes to fish communities are evident, and findings from adjacent waters
suggest changes in phytoplankton and zooplankton communities as well; the benthos has
not been studied robustly enough to determine if major shifts might be occurring, and is
an area ripe for further study. Existing data however, suggest relative stability of the
Ocean SAMP zooplankton community over the past several decades, which does not
agree with trends reported for the larger North Atlantic area. Altered ecosystem
conditions are allowing for various native species to increase in abundance, sometimes to
nuisance proportions, and non-native (invasive) species are gaining a toe-hold as they
expand their ranges, often out competing and excluding native species in the process.
While less is known about marine microbial communities and disease organisms in
Ocean SAMP waters, lobster shell disease is prevalent in the area and is being tied to
changing climatic conditions. The northerly spread of shellfish diseases such as Dermo
and MSX are also being documented, and again appear to be related to warming waters
throughout the area.
15. In summary, the Ocean SAMP region is a dynamic, biologically productive, unique
marine habitat area that is similar to nearby waters. It also is different in that it abuts two
major eco-regions, and is therefore an expression of both. The Ocean SAMP region, like
nearby areas, appears to be undergoing change as a result of changing climatic
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 11 of 132
conditions. Our knowledge-base for the Ocean SAMP area however, is patchy, and much
of it outdated. This makes it an even further challenge to understand its complex ecology.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 12 of 132
Section 210. Geological Oceanography
1. The basic geological characteristics of the Ocean SAMP area create the foundation for its
ecology. Large scale features, such as glacial moraines and boulder fields, are largely stable
over long spans of time. Smaller scale features however, influence the physical forces of
waves, tides and currents that move and sort the sediments which form the basic benthic
habitat types available for colonization by organisms. Some of these habitats are fairly stable
(e.g., boulders) while others are quite transitory (e.g., sand waves). Each habitat type
supports different communities of organisms that make up the mosaic of benthic life in the
Ocean SAMP area.
2. The geology of a region determines the basic characteristics upon which physical, chemical
and biological elements of the ecosystem build. The geology is generally a static or slowly
changing element of the landscape, though cataclysmic alteration (e.g., an earthquake or
volcanic eruption) can occur and bring rapid, dramatic change. Block Island Sound, Rhode
Island Sound, and the Offshore Ocean SAMP area, derive their basic topography and
geology from Pleistocene glaciation activity, in particular the Wisconsinan Laurentide ice
sheet that reached its maximum extent about 24,000 years ago (Stone and Borns 1986;
Boothroyd and Sirkin 2002). The maximum southern extent of the ice sheet falls within the
Ocean SAMP area, and its retreat created a unique patchwork landscape of boulders, sand,
gravel, and moraine features that make up the ecological foundation of Rhode Island Sound,
Block Island Sound and the Offshore Ocean SAMP area region.
3. Marine waters are estimated to have entered Block Island Sound and Rhode Island Sound
about 9,500 years ago when sea level was 35 m lower than at present. Prior to that time,
ancient glacial lakes were in existence, and drainage from the lakes helped create some of the
major submarine features (e.g., canyons) on the Continental Shelf (Figure 2.2). Sea level rose
at an estimated rate of 2 m per century, filling the ancient lakes with seawater, then slowing
to a rate of 30 cm per century (3 mm yr-1) about 5,000 years ago (Boothroyd 2009). Current
sea level rise rate at Montauk, New York is 2.78 mm yr-1 (± 0.32 mm yr-1; NOAA Tides and
Currents n.d.); the tidal station at Newport, Rhode Island, is experiencing a sea level rate of
rise of 2.58 mm yr-1 (± 0.19 mm; NOAA Tides and Currents n.d.), the station in New
London, Connecticut a rate of rise of 2.25 mm yr-1 (± 0.25 mm; NOAA Tides and Currents
n.d.) and the station on Nantucket Island, Massachusetts a sea level rise rate of 2.95 mm yr-1
(± 0.46 mm yr-1; NOAA Tides and Currents n.d.) . It is expected that the Ocean SAMP area
would currently experience a rate of sea level rise somewhere within the bounds of the
Montauk, New London, Newport, Nantucket tide stations (2.25–2.95 mm yr-1). The overall
impact of rising sea level on the ecology of the area, with its subsequent loss as well as
creation of new habitat, is not known (see Chapter 3, Global Climate Change, for further
discussion of sea level rise in the Ocean SAMP area).
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 13 of 132
Figure 2.2. Schematic of approximate location of major glacial lakes and direction of drainage flows approximately 19,000 years ago, and
which helped create current seabed topography. Adapted from Uchupi et al. (2001).
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 14 of 132
4. The geological features of Rhode Island and Block Island Sounds have strong influence on
the physical oceanographic characteristics of those water bodies, which in turn has
significant influence upon biological and ecological processes. Glacial moraines for instance,
span the Ocean SAMP area, creating unique bottom topography which influences the
patterns of currents, and creates a mosaic of habitats (e.g., sediment types) which diversifies
the overall ecological fabric of the area (Figure 2.3). The moraine features, in general, are
composed of coarse materials such as boulders and large rock. These materials provide
vertical relief on the seafloor, which influences currents and provides greater surface area for
colonization by attached organisms. In this way the moraines provide for habitat complexity.
While other elements of the ecosystem may change dramatically and rapidly in response to
changing climate, storms, and other perturbations, the basic geological foundation will
remain as a solid influence in the face of all but the most catastrophic of events (e.g.,
volcanic activity). The basic resiliency of the benthic environment in the region has allowed
the development of what appears to be a relatively stable benthic ecological community (see
Section 250.2 for further details).
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 15 of 132
Figure 2.3. Location of glacial moraines in the Ocean SAMP area. The map is a composite of the moraines as defined by several
researchers, shown according to compositional materials to emphasize the largest possible extent of the more substantial bottom materials
such as boulders. These features help shape physical oceanographic forces such as currents, as well as benthic ecological habitats.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 16 of 132
5. The glacially derived bottom topography and composition determines the benthic
characteristics that will create the ecological habitats of Rhode Island and Block Island
Sounds. Boothroyd (2009) finds that the seafloor bottom in the Ocean SAMP area is
characterized by four (4) major depositional environments, presented below in order of
increasing grain size:
a.
A shore-parallel feature, called a depositional platform sand sheet, comprised of
medium sand containing small ripples. This feature serves an important function
as a short-term sand storage area for supplying alongshore transport of sand to the
east, or onshore transport to shoreline environments. These features provide
habitats that regularly undergo significant change;
b.
Features that are slightly lower than the cobble–gravel surrounding them, called
cross-shore swaths, are composed of medium to coarse sand with small dunes.
These features serve as a conduit for sand transport during storm events (Griscom
1978; Hequette and Hill 1993), providing habitat that undergoes regular, but less
frequent, alteration;
c.
Cobble gravel that is in equilibrium (e.g., no loss or accretion), but often
rearranged after and during storm events, called depositional gravel pavement.
These features provide habitat that is relatively stable, yet subject to occasional
disturbance;
d.
Concentrations of boulders and gravel inherited from the moraine, referred to as
glacial outcrops, and which are more or less fixed in place, providing long-term
habitats.
These features, containing sand, coarse sand, cobble–gravel, and boulders, describe the
composition of the major benthic environments found in the Ocean SAMP area. These
features are characteristic, though not definitive, of the seafloor composition which shows
gradation from and between one to another of these features.
6. While the basic overall geology of the Ocean SAMP area can be considered to be static, the
actual local, physical, benthic environment found on the bottom is not. Sediments and bottom
features are continually subjected to physical forces that alter their characteristics, and their
location on the seafloor. Upwelling and downwelling currents, the orbital motion of waves,
and unidirectional lateral flows all act upon and alter bottom features. Likewise channels,
bottom topographic high points, and other bathometric features will influence as well as
create these flows and currents. The flows and currents promote the transport of sand-sized
materials and the migration of large bedforms such as dunes, sand ripples and sand waves,
across the bottom. The sorting, movement, and placement of seafloor sediments that occurs
during these processes creates a patchwork of habitats ranging from fine silts to gravelly
areas to boulder fields (Figure 2.4; and see Figures 2.25 and 2.26). The diversity of physical
habitats is a powerful influence on benthic ecological make up, determining what species will
reside in what habitats in the bottom community; most often, the greater the structural
physical diversity of an environment, the greater the biotic diversity of that ecosystem
(Eriksson et al. 2006). Since these ecological “shaping” processes are ongoing, the bottom
community of the Ocean SAMP area, particularly those comprised of mud, sand, and/or silt,
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 17 of 132
are in a constant state of flux as habitat patches are altered or destroyed, moved or recreated
along the bottom. These benthic communities within the Ocean SAMP area could therefore
be expected to be composed of organisms that can withstand, and perhaps even thrive in an
ever changing physical benthic environment.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 18 of 132
Figure 2.4. Bottom characteristics in a section of Rhode Island Sound as interpreted from
sidescan sonar images (McMullen et al. 2008; their Figure 14 (upper) and Figure 10
(lower)). Note the large expanses of sandy area punctuated by scattered boulders in the
upper panel. Yellow area in the lower panel shows more stable habitat areas, with orange
(sand areas in the upper panel) areas being more transitory.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 19 of 132
7. In recent side scan sonar surveys of portions of Rhode Island Sound (Figure 2.4), McMullen
et al. (2008) found a mosaic of sedimentary environments that are the result of erosion and
sediment transport, deposition and sorting, and reworking, with large areas comprised of
transitory coarse-grained materials. Boulders were found scattered throughout the study area,
though there were areas where concentrations of boulders existed, and which create areas of
increased habitat complexity which would promote higher species diversity. Depositional
areas where sediments were sorted and reworked tended to be found along channels and
bathymetric high points. A preponderance of commercial fish trawl marks in depositional
areas suggests an abundance of commercially important demersal fish species in these
habitat/environment types. This in turn suggests a highly productive benthic community
which is providing a rich food source. McMullen et al. (2008) found sand waves to be a
predominant feature, and infer they are a result of coarse-grained bedload transport as was
noted previously in this section. These features highlight the glacial origins of the area, and
the stability of various features, for example glacial till, but also the transitory nature of other
features, such as sand waves. Both bottom types—transitory and stable—are important
characteristics in defining benthic habitat, and the types of organisms that will thrive there.
8. In an earlier survey conducted in Block Island Sound, Savard (1966) described the east–
central portion as a smooth plain with an average depth of 34 m, with the rest of the section
being dissected by holes, ledges and submerged valleys and ridges. In the area north of Block
Island, the Savard (1966) found a northerly running ridge flanked by deep holes, and
submerged hills and valleys. The deepest hole in Block Island Sound is an area 100 m deep
located 6.4 km south of East Point on Fishers Island. This description notes similar features
in Block Island Sound as are seen in Rhode Island Sound, and reinforces the existence of a
mosaic of common bottom habitats through the Ocean SAMP area.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 20 of 132
Section 220. Meteorology
1. Wind, waves, and storms are important forces shaping marine ecosystems. They influence
water column mixing, current patterns and the transport of waterborne particles and
planktonic organisms, as well as drive transport and sorting of bottom sediment. Water
column mixing is enhanced by the turbulence created by winds and waves, thereby
increasing oxygenation, and replenishing nutrients to the water column where they fuel plant
production. Storms, although episodic, can create severe wind and wave stress, rapidly and
completely breaking down stratification, altering seasonal productivity, and shaping both
benthic and pelagic community composition. All these forces and their resulting influence on
the area play a role in shaping the overall ecological makeup of the Ocean SAMP area.
2. A unique feature of Block Island Sound is that the impacts of large storm systems may be
naturally mitigated, to some degree, by the submerged portion of the glacial moraine that
extends from the eastern tip of Long Island to Block Island, and then continues northward
toward Point Judith (see Figure 2.3). The moraine acts as a submerged jetty at the mouth of
Block Island Sound, dissipating storm wave energy (Driscoll 1996). The degree of storm
buffering provided, and its effect on Ocean SAMP area ecological and physical
oceanographic functions, is not well understood. Though not cited as a cause-and-effect
relationship, Spaulding (2007) reports that wave heights within Block Island Sound are 40–
60% smaller than those propagated offshore.
220.1. Wind
1. While winds are a highly variable phenomenon, there are seasonal, and daily, patterns that
occur and that influence various physical attributes of the water column and sea surface. By
exerting this influence, wind no doubt plays a role in shaping the ecology of the Ocean
SAMP area, though specific study of this is lacking.
2. Winds in the Ocean SAMP region contain a seasonal, diurnal (e.g., late morning through late
afternoon/early evening), summer sea breeze component blowing from the southwest, with
winter winds generally blowing from the northwest, and stronger than during summer (Loder
et al. 1998). Winter northwesterlies often generate rough seas in Block Island Sound
(Williams 1967), with east and southeast winds producing the biggest waves, up to 7 m
reported. Wind velocities during winter months tend to be, on average, twice the speed of
summer winds (Figure 2.5; O’Donnell and Houk 2009). Maximum wind speeds also show
seasonality, but with a distinct decrease during May and June followed by a sharp increase
during July and the early part of August (Figure 2.5). Increased maximal wind speeds during
late summer assists in the breakdown of water column stratification. For instance, Shonting
and Cook (1970) found wind stress to be an important element in the breakdown of the
seasonal thermocline (e.g., stratification due to differences in temperature between surface
and bottom water) in Rhode Island Sound.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 21 of 132
Figure 2.5. Average annual, average maximum, and average minimum wind speeds over
the Ocean SAMP area. (Spaulding 2007).
3. Winds have not been shown to play a major role in driving the long-term circulation patterns
observed in Rhode Island Sound or Block Island Sound, though on a seasonal and shorter
time frame basis wind can be a significant factor. Summer south westerly winds (e.g., sea
breeze), while only half as strong as winter winds, drives upwelling along the coast which
appears to help drive the flow of Long Island Sound water towards the shelf and offshore
(O’Donnell and Houk 2009). Codiga and Ullman (2010) and Ullman and Codiga (2010) have
found that during winter months a weak, non-wind driven upwelling pattern is observed in
Rhode Island Sound and in the offshore Ocean SAMP area. Westerly summer winds also
tend to increase the exchange of water between Block Island Sound and Rhode Island Sound,
while winter winds, predominantly from the northwest, promote increased water column
mixing rather than increased horizontal exchange (Gay et al. 2004). This mixing may help
bring nutrients into the water column for uptake by phytoplankton, perhaps contributing to
spring blooms when they occur. Codiga and Aurin (2007) further support the above through
direct observations, finding that the volume of water exchanged between Long Island Sound
and Block Island Sound was weakest during winter months.
4. Pilson (2008) reports long-term changes occurring in the winds experienced over
Narragansett Bay; a nearly 4.0 km per hour (1.11 m sec-1) decrease in annual average wind
speed has occurred since 1950, with westerly winds (e.g., blowing to the east) showing this
trend more markedly than winds in other directions. Whether these patterns are applicable to
the broader Ocean SAMP area is not known, but trends towards decreasing wind speeds,
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 22 of 132
suggested to be related to climatic warming, may have the potential to impact water column
stratification events, upwelling of nutrients, and perhaps the overall ecology of the area as
well.
220.2. Storms
1. The Ocean SAMP area is not an area regularly frequented by hurricanes—there has not been
a single hurricane strike (to Rhode Island) since 1996, despite the period 2000–2010 being
labeled one of the most active hurricane periods on record (NOAA Coastal Services Center
n.d.). Figure 2.6 shows the historical record of hurricane activity in the Ocean SAMP area
(e.g., those hurricanes where the eye crossed into Rhode Island). The historical record shows
17 hurricanes making landfall in Rhode Island; 7–Category 1, 8–Category 2 and 2–Category
3 rated storms. The most recent Category 3 hurricane was Esther during 1961, and the most
recent named hurricane was Bob, a Category 2 hurricane, during 1991. Hurricanes and
intense storms systems however, can have significant impact on marine ecosystems. For
instance, Smayda (1957) found a 16 to 27-fold increase in phytoplankton standing crop at the
mouth of Narragansett Bay following the passage of major hurricanes. Storms, particularly
hurricanes because of their intense winds, have the ability to significantly impact marine
aquatic ecosystems since the depth to which wave generated orbital motion will be deep, and
can impact the bottom (e.g., First 1972), particularly transitory bottom types as described in
Section 210. How such a disturbance event might influence the ecology of the Ocean SAMP
area is not known, but it could be presumed that benthic habitat would be disturbed, and that
some impact, positive or negative, would be imparted.
Figure 2.6. Hurricane tracks where the eye moved over Rhode Island, intersecting the
Ocean SAMP area (NOAA Coastal Services Center n.d.).
2. While hurricane frequency in the Ocean SAMP area has generally been low, there is strong
evidence that the power dissipation index (PDI, a measure of destructive potential) has
markedly increased since 1980 (e.g., Emanuel 2005; Webster et al. 2005). This increase
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 23 of 132
correlates well with variations in tropical Atlantic sea surface temperature (Mann and
Emanuel 2006; Holland and Webster 2007), which have been shown by numerous studies
and reports to be on the increase, and has been linked to increased warming due to climate
change (IPCC 2007). While currently not considered a major ecological driver, the potential
impacts of more frequent intense hurricanes on Rhode Island Sound and Block Island Sound
ecology, circulation dynamics, and sediment transport, has not been well considered, but
could be significant, and would be dependent both on the frequency and intensity of the
disturbance events.
3. Southern New England coastal waters experience frequent intensive wintertime storms
referred to as Nor’easters that generate strong alongshore currents and cross-shelf pressure
gradients that can be felt from Cape Cod to Cape Hatteras (Beardsley et al. 1976). These
storms are largely responsible for the episodic events that drive destructive waves and
currents, and ultimately sediment transport along the coastlines resulting in beach erosion
and sediment re-suspension offshore. While impacts of Nor’easters are well known for
Rhode Island shorelines, their impact, if any, on the ecology of the Ocean SAMP area is not.
Nearshore benthic habitats would certainly be impacted as sand was moved across
depositional environments (see Section 210). Boicourt and Hacker (1976) however, note that
winds associated with Nor’Easters can move waterborne particles, similar in size to common
zooplankton and larval fishes, 40 to 80 km over the course of the several days that these
storms hold together and create strong winds over an area. Such movement could have
considerable short-term impacts upon planktonic organisms, particularly settlement patterns
and juvenile survival rates for a variety of vertebrate and invertebrate species. While such
events, because they occur infrequently, would tend to have short term impact upon the
ecology (e.g., poor juvenile survival in a given year class), increasing frequency of such
events due to climate change increases the probability that ecological impact could occur.
4. All storms facilitate a “storm surge,” which is a wave of water created by strong winds
blowing in a given direction for extended periods of time. The size of the storm surge is
dependent largely upon the wind speed, though bottom bathymetry, water depth, and
duration of high wind speed are all important contributors. For the Ocean SAMP area,
probable storm surge over given time frames are: 10 year–2.52 m; 50 year–3.51 m; 100 year–
3.58 m; SPH (Simulated Particle Hydrodynamics)–4.85 m (Spaulding 2007). Asher et al.
(2009) modeled slightly higher storm surges: 50 year–4.376 m; 100 year–4.446 m. The
impact of storm surge on the ecology and/or physical oceanography of the Ocean SAMP area
is not well known, though coastline areas would be suspected to receive the greatest impact
from such events.
5. It has been noted that major storm tracks have been moving northward as a result of changing
climate (Yin 2005). Major storms have the capacity to drive ocean circulation via wind
stress, and can have significant impacts on vertical mixing of the water column (Hays et al.
2005), and hence upon water column stratification. If increased frequency and/or increased
strength of storms alter circulation patterns in the Ocean SAMP area, plankton and larval fish
distribution, and regeneration of nutrients into the water column, could be altered. Such
change could alter the ecology of the Rhode Island Sound and Block Island Sound
ecosystems, though in what ways and by what mechanisms is not known.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 24 of 132
Section 230. Physical Oceanography
1. Rhode Island Sound, located in the eastern section of the Ocean SAMP area (Figure 2.1),
encompasses approximately 1,530 km2 (Shonting and Cook 1970), is bounded to the west by
the eastern side of Block Island, to the north by the Rhode Island coast, and to the east by
Martha’s Vineyard and Nantucket Shoals. Rhode Island Sound is open to the Atlantic Ocean
to the south, and has an average depth of 31 m and reaches depths of about 60 m, with a
calculated volume of 4.74 x 1010 m3 (surface area x average depth; McMullen et al. 2007;
Shonting and Cook 1970). Rhode Island Sound exchanges water with Narragansett Bay
through the East and West Passages, with the Sakonnet River, Buzzards Bay, Vineyard
Sound and Block Island Sound, and with the Offshore Ocean SAMP area region of the
Atlantic Ocean.
2. Block Island Sound, located in the western section of the Ocean SAMP area (Figure 2.1),
encompasses approximately 1,350 km2 (Staker and Bruno 1977), is bounded to the east by
the western shore of Block Island, to the north by the Rhode Island coast, and to the west by
Long Island, Fishers Island, and Long Island Sound. Block Island Sound is open to the
Atlantic Ocean to its south, has an average depth of 40 m, reaching depths of 100 m, and has
a calculated volume of 5.4 x 1010 m3 (surface area x average depth; Staker and Bruno 1977).
Block Island Sound exchanges water with Long Island Sound through The Race and via a
smaller opening between the east end of Fishers Island and Napatree Point, and the Offshore
Ocean SAMP area to the south. A shallow sill (part of the moraine; see Figure 2.3) extends
from Montauk Point to Block Island at a depth of 15–25 m, and partially isolates Block
Island Sound from the Continental Shelf (Edwards et al. 2004). A canyon—Block Channel—
extends several tens of kilometers from the deepest point of the sill, forming a deep
connection between Block Island Sound and the Offshore Ocean SAMP area region of the
Atlantic Ocean (Edwards et al. 2004).
3. The region immediately south of Rhode Island Sound and Block Island Sound, roughly that
area south of Block Island to the Continental Shelf Slope (Figure 2.1), is considered here to
be the Inner Continental Shelf, and will be referred to as the Offshore Ocean SAMP area
throughout this chapter. The Offshore Ocean SAMP area region shows a strong overall
current flow to the west (Cowles et al. 2008). Winds over the Offshore Ocean SAMP area are
highly variable and seasonal, tending to be light in summer with infrequent strong wind
events in both fall and spring; intermediate to strong wind events occur more frequently
during winter (Cowles et al. 2008). Waters of the Offshore Ocean SAMP area become
strongly stratified on an annual cycle, being generally well mixed throughout the winter and
strongly stratified in summer due to a combination of heating, freshwater influence and
reduced wind strength (Cowles et al. 2008). The breakdown of stratification on the Offshore
Ocean SAMP area results mainly from the impact of wind from the west. Cowles et al.
(2008) report a front that separates fresher, nearshore shelf water from salty continental slope
water, to be a prominent hydrographic feature located between 70 and 100 m isobaths (see
Section 230.4.1 for further details). Cowles et al. (2008) also report that warm core rings,
calved from the Gulf Stream, occasionally enter the area and may have significant but short-
term impact on circulation over the Offshore Ocean SAMP area region. Another perturbation
in the form of low salinity water from the Long Island Sound system is seen during years of
very high river flow (Cowles et al. 2008).
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 25 of 132
4. The physical oceanographic components of marine systems, such as tides, water temperature
and circulation, have broad, and often strong influence over chemical and biological
processes. Freshwater input for instance, mainly from Long Island Sound in this case, sets up
and strongly influences water circulation in Block Island Sound. Rhode Island Sound is
influenced by the circulation patterns of Block Island Sound, and by water moving in across
the Offshore Ocean SAMP area and from the east across Nantucket Shoals. The mixing and
mingling of these different masses of water, particularly with regard to vertical mixing which
is a critical parameter for nutrient recycling and the breakdown of water column
stratification, creates a dynamic environment over both space and time.
5. Beardsley et al. (1985) referred to the general area encompassed by the Ocean SAMP as a
“mixing basin” because of the diversity of water types and species that were observed. At the
scale of the North Atlantic Ocean, the Gulf Stream moves warm water northward, with a
return flow of cold water moving southward from the Gulf of Maine. Warm water from the
Gulf Stream interacts with the water on the Offshore Ocean SAMP area (Beardsley et al.
1985), and provides opportunities for southern species to access the Ocean SAMP area.
Figure 2.7 depicts the large scale general flow of water in the Ocean SAMP region. A large,
meandering lobe of warm water can be seen extending northward towards the Ocean SAMP
area. Sometimes these lobes break free and are referred to as “warm core rings,” that bring
distinctive pockets of tropical water, including the biota entrained in it, onto the Continental
Shelf where interaction with the Ocean SAMP area is possible. There are also distinct current
flows that move from north to south, originating in the Gulf of Maine, moving around Cape
Cod and then into and influencing the Offshore Ocean SAMP area region (Figure 2.7; Loder
et al. 1998). In this fashion the Ocean SAMP area has contact with the larger Northeast US
Large Marine Ecosystem, the cold northern water and the species that travel with it, as well
as warm southern waters and the biota it carries. It should be noted however, that in the
Ocean SAMP area there is a general flow to the southwest, exiting the Ocean SAMP area,
and a commensurate inflow into the area from the northeast. Because of this, the Ocean
SAMP area has a higher probability of coldwater species from the north entering the area.
This also accentuates this importance of unusual events, such as storms from the south or
Gulf Stream warm core rings, fostering the entry of more southerly species.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 26 of 132
Figure 2.7. Schematic representation of northern cold water currents, southern warm
water currents, and Gulf Stream warm core rings entering the Ocean SAMP area, making
it a very dynamic ecosystem. Warm core rings graphic from: Coastal Carolina University
n.d.
6. While there have been studies of the physical oceanographic characteristics of the Ocean
SAMP area, many of them are geographically limited in their scope and do not portray a
picture of how the area functions as a connected, dynamic system. A practical way to
proceed at a systems-level scale is through modeling. The physical oceanography of the
Ocean SAMP area however is complicated due to complex topography, which makes
modeling attempts more challenging. Furthermore, a major challenge will be linking
biological/ecological functions to physio-chemical processes to gain an ecosystem-based
view of the region as a functional whole. Dr. Changshen Chen and collaborators have
developed the U.S. Northeast Coastal Ocean Forecast System (NECOFS), which contains
detailed geometry for Rhode Island Sound and Block Island Sound. Future application of this
model to the Ocean SAMP area would assist in better understanding circulation dynamics,
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 27 of 132
and the ecology because biological components can be incorporated into the model to
develop an ecosystem-level understanding. Many detailed aspects of physical oceanography
in the Ocean SAMP area based on Finite Volume Coastal Ocean Model (FVCOM)
hydrodynamic simulations, which underlie NECOFS, have been described by Codiga and
Ullman (2010).
230.1. Waves
1. Wave analysis performed by Spaulding (2007) found that nearly 53% of the waves in the
Ocean SAMP area come from three dominant directions: 22% from the south, 19% from the
south southwest, and 12% from the south southeast, with average annual wave heights for
each direction: 1.09 m (SSE), 1.15 m (S) and 1.29 m (SSW). Asher et al. (2009) are in
agreement that the greatest frequency of waves, regardless of size, come from a southerly
direction, with a mean wave height of 1.2 m and an extreme height of 8.4 m. Spaulding
(2007) estimated probable wave height extremes for 10 year: 6.5–7.0 m; 25 year: 7.5–7.75 m;
50 year: 8.2–8.35 m; 100 year: 8.8–9.0 m frequencies. Asher et al. (2009) also estimated 9.0
m extreme wave height at a 100 year frequency, but noted that the probability of such a wave
was not applicable to all Ocean SAMP areas. They found that geography influenced wave
height, with waves from the south and the southeast having the greatest potential for larger
size, with 10+ m extreme waves possible. Ullman and Codiga (2010) found average wave
heights to range from 0.5 m to 2.5 m, with waves of less than 0.5 m occurring for less than a
day during winter and up to several days during summer. Asher et al. (2009) found that the
moraine stretching between Block Island and Montauk provided a wave damping action,
with a net result that extreme wave heights would be 2–3 m less to the west of Block Island
(versus to the south or southeast). This may be important ecologically as it tends to create an
environment less influenced by disturbance events.
2. Average wave heights in the Ocean SAMP area tend to be 1–3 m, and overall, would be
expected to have little impact on bottom waters, though surface waters would tend to stay
well mixed. Larger waves, generated by winds associated with storms, will have a greater
potential to impact the water column, particularly water column stratification. Ullman and
Codiga (2010) found waves larger than 2.5 m in height to be associated with strong wind
events, generally lasting 3 to 8 days, and being slightly more common during winter. First
(1972) found that statistically modeled wave induced bottom velocity should be strong
enough, given 97 km hr-1 (60 mph) winds, to impact bottom sediments at a depth of about 60
m (e.g., Cox Ledge). From their modeling efforts, First (1972) further determined that wave
induced bottom impact in water depths of 60 m should occur 1.5–4.9% of the time between
September and November. This suggests that high intensity winds have the potential to
mobilize sediment at the surface of the seafloor throughout much of the Ocean SAMP area,
reworking sediments and sorting them as described previously (see Section 210). The impact
of wave disturbance on the benthic environment of the Ocean SAMP area is not well known.
230.2. Tides and Tidal Processes
1. Tides are a constant physical attribute of marine ecosystems in the New England area. Their
impact along the shoreline in shaping intertidal ecology is apparent, though in deeper,
offshore waters the influence of the tides may be less obvious. Tides are of major importance
in that they set up currents that alternate in direction every flood and ebb tide, moving water
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 28 of 132
and waterborne constituents from place to place. Due to its geomorphology, tides in the
Ocean SAMP area are major forces that shape circulation in the region, and tidal interaction
with Long Island Sound is a defining feature of tidal circulation dynamics.
2. The Ocean SAMP area experiences a dominantly semi-diurnal tide (e.g., nearly twice daily)
with a mean tidal range of about 1.0 m (Shonting and Cook 1970). The most extreme tide
measured at the Newport gauge station was 2.96 m high on 19 August 1991 with the passage
of Hurricane Bob, though this was due to storm surge plus the high tide, not just tidal
influence (NOAA Tides and Currents n.d.). The diurnal tides move water from the Offshore
Ocean SAMP area towards the sounds and then in an opposite direction on the following
change of tide. The intensity of tidal interchange is much stronger in Block Island Sound than
in Rhode Island Sound due to stronger tidal velocities, though how this influences ecological
differences between the two sounds, if any, is not known. The tides also interact with
connected bodies of water such as Nantucket Shoals, Buzzards Bay, Narragansett Bay and
Long Island Sound, moving water throughout the various ecosystems.
3. Long Island Sound, because of the large volume of freshwater it receives, and the narrowness
of the connection to Block Island Sound (e.g., The Race), is a significant influence upon the
physical oceanographic and chemical characteristics of Block Island Sound. Current
velocities in The Race, which are tidally driven, are strong (e.g., > 5 knots; Figure 2.8), and
water moving out of Long Island Sound moves a considerable distance into Block Island
Sound, and even into Rhode Island Sound. Freshwater, nutrients, pollutants and biota are
mixed, mingled and exchanged between these water masses during each tidal cycle,
particularly in the Block Island Sound ecosystem. The intense current flow at The Race, and
at Montauk Point, create ideal feeding conditions for predatory fishes and these spots are
noted regionally as prime fish concentration areas.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 29 of 132
Figure 2.8. Water current velocities in Block Island Sound, particularly at The Race,
showing the intense current speed in that area..
4. Riley (1952) described the tides in Block Island Sound as a progressive wave, with low water
occurring 1½ hours earlier at Block Island than at The Race (the entrance to Long Island
Sound). Riley found the topography of Block Island Sound to be a major force on tidal flows
due to the variety of slopes and troughs found as bottom features. Such features create drag
and turbulence, as well as upwelling and perhaps even downwelling currents, all of which
influence sediment transport and sorting, and the overall ecological character of the benthos
and water column.
5. Shonting and Cook (1970) found that tidal currents in Rhode Island Sound tended to have a
northwest to southeast flow, but that this was quite variable due to the influence of wind
stress and turbulent flow around shoals and islands (e.g., complex bottom topography). The
major tidal flow in the Ocean SAMP area is via bottom water moving through Block Island
Sound from offshore and into Long Island Sound via The Race (Edwards et al. 2004), and
out again on the opposing tide.
6. Tidal flow from Long Island Sound interacts considerably less with Rhode Island Sound than
it does with Block Island Sound. On the ebb flow from Long Island Sound, water runs east to
the north of Block Island and interacts with the western edge of Rhode Island Sound. The
majority of the ebb flow however moves out and around Montauk Point, creating high
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 30 of 132
current velocities (Figure 2.8), and then to the southwest parallel to the coast of Long Island
and into the Mid-Atlantic Bight region (Edwards et al. 2004). Various studies (Koppelman et
al. 1976; Kenefik 1985; Codiga and Rear 2004) suggest that more than 50% of the tidal
transport entering Block Island Sound from Long Island Sound exits to the south between
Montauk Point and Block Island. In all cases, the flow from Long Island Sound tends to be
lower salinity water than that originating in the sounds, which has implications for mixing,
stratification, circulation, and the ecology.
230.3. Hydrography
230.3.1. Temperature
1.
Water temperature is a key criterion in determining the distribution of organisms, most all
of which are limited to some degree geographically by physiological thermal tolerance
that sets northern and southern (and often depth) limits to their range. Temperature is also
an important factor that defines the density of water, which sets up circulation patterns at
both vertical and horizontal scales, and plays an important role in water column
stratification. In the Ocean SAMP area, temperature is highly seasonal, and therefore
ecological change is highly seasonal as well. As a major element in defining the “comfort
zone” of many marine organisms, temperature is a critical ecological variable.
2.
Codiga and Ullman (2010) found during summer months that the warmest waters (11–
21°C), at both surface and bottom of the Ocean SAMP area tended to reside in central
Rhode Island Sound, and that Block Island Sound and the eastern portions of Rhode
Island Sound were typically 1–2°C cooler. This is largely because stronger vertical
mixing in Block Island Sound tends, as a result of its interaction with Long Island Sound,
to keep the water column better mixed and temperatures therefore slightly cooler. It is
unclear if this difference in summer temperatures plays any ecological role.
3.
During winter, warmest waters occur offshore in the area around Cox Ledge, with lowest
temperatures found along the periphery of the sounds abutting the landmass of the coast
(Codiga and Ullman 2010). During summer, the warmest waters are seen in northern and
central Rhode Island Sound, while Block Island Sound, the area around Block Island and
the eastern portion of Rhode Island Sound are cooler, because of the influence of Long
Island Sound (Codiga and Ullman 2010). A distinct thermal front (where two water
masses that differ in their physical and/or chemical attributes collide) is noted south of
Block Island at the periphery of cooler waters, and this front is coincident with a salinity
front derived from the input of lower salinity water from Long Island Sound (see Section
230.4.1). During autumn, central Rhode Island Sound remains slightly warmer than
adjacent waters.
4.
Temperature data (Taylor et al. 2009) have been collected by the Northeast Fisheries
Center as part of its Marine Resources Monitoring, Assessment and Prediction Program
(MARMAP) conducted within the Northeast Continental Shelf ecosystem, with data
collected at a suite of stations located within Ocean SAMP boundaries. Figure 2.9 shows
the seasonality of water temperature, at both surface and bottom, showing a clear
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 31 of 132
difference in temperature (6–7°C) between surface and bottom from early spring through
late fall, confirming that this is the time most probable for the water column to stratify.
Figure 2.9. MARMAP water temperature data for all stations located within the Ocean
SAMP area, and for all years of sampling (Taylor et al. 2009). Seasonality of collected
data, as well as level of sampling effort over time, is shown in the stacked graphs to the
right.
5. Figure 2.10 shows water temperatures within the Ocean SAMP area on a seasonal basis, and
at various depths. It is important to note that during winter, bottom waters are considerably
warmer than at surface or at mid-depth. Fish will often spend winter months near bottom
where this thermal refuge exists (Sanders 1952; see Section 250.3). During summer months,
bottom waters are cooler than at surface or at mid-depth, and fish will congregate near
bottom as a refuge from warm surface waters that may be near the upper limit of their
thermal tolerance. Strong storms that mix the water column could influence the occurrence of
thermal refuges, though this has not been documented.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 32 of 132
Figure 2.10. Seasonal water temperatures at sea surface, 20 m depth, and seafloor in the
Ocean SAMP area, based on archived CTD data collected between 1980 and 2007 (from
Codiga and Ullman 2010).
6. O’Donnell and Houk (2009) and Kaputa and Olsen (2000) note a strong seasonal signal in
temperature at both surface and bottom at a station located northwest of Block Island, and
about ¾ of the distance to The Race. Figure 2.11 shows the seasonal peak in water
temperature consistently occurs in later summer/early fall (Aug/Sep), with the seasonal low
occurring in late winter/early spring (Feb/Mar). During those years where surface and bottom
temperatures are nearly identical (e.g., 1996), the water column is most likely well mixed.
Conversely, in those years where surface and bottom temperatures are considerably divergent
(e.g., 1998), the water column appears not to be well mixed and water column stratification is
likely.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 33 of 132
Figure 2.11. Average annual surface and bottom temperatures at a station in Block Island
Sound (CTDEP No. N3; between NW of BI, ¾ of the way to The Race; from O’Donnell
and Houk 2009).
230.3.2. Salinity
1. The seasonal input of freshwater is important to the ecology of the Ocean SAMP area—it
brings an influx of terrestrial-based nutrients to fuel plant growth. The freshwater influx also
promotes exchange with offshore bottom waters by fostering a return flow that offsets
surface water outflow to offshore areas. It also brings the potential to promote water column
stratification, particularly later in the season when overall wind speeds over the area
decrease, and water temperatures increase. All of these factors shape the ecological
composition of the Ocean SAMP area.
2. Long Island Sound estuarine circulation, driven primarily by the freshwater input of the
Connecticut and Thames Rivers, is the major freshwater influence on Block Island Sound
and the overall Ocean SAMP area (see Section 230.4). No large rivers or streams flow
directly into Block Island Sound because of the terrestrial-based Charlestown Moraine which
diverts all surface water flow either to the east to Narragansett Bay, or more generally to the
west and into the Pawcatuck River system (Savard 1966).
3. Narragansett Bay is not considered to be a major source of fresh water to the Rhode Island
Sound ecosystem, and does not appear to be a significant factor in circulation dynamics
(Codiga and Ullman 2010). Shonting and Cook (1970) suggest that freshwater from
Narragansett Bay influences Rhode Island Sound, but with a 2 to 3 month lag time; they
found the mean salinity of Rhode Island Sound to be inversely related to freshwater runoff
into Narragansett Bay. Further study is needed to verify or deny these suggested interactions.
4. Codiga and Ullman (2010) show salinity, which is strongly influenced by freshwater input, in
the Ocean SAMP area by season, and at various depths (Figure 2.12). During winter, salinity
is higher at bottom than at surface, with higher salinity water occurring with distance moved
offshore (Figure 2.12). Salinity decreases during spring, particularly at surface and mid-depth
as would be expected due to spring rains and snowmelt runoff into river systems. Summer
salinities are very similar to those seen during spring throughout the water column. Fall sees
a shift towards increased salinity, particularly at surface and mid-depth, as would be expected
during dry late summer and early fall months. Spring and summer see the strongest salinity
differences at horizontal and vertical scales, which corresponds to the occurrence of the
seasonal “front” to the south of Block Island (see Section 230.4.1).
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 34 of 132
Figure 2.12. Seasonal water salinities at various depths in the Ocean SAMP area based
on archived CTD data collected between 1980 and 2007 (from Codiga and Ullman 2010).
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 35 of 132
5. The Atlantic Multidecadal Oscillation (AMO) is a 65–80 year oscillation in sea surface
temperatures in the North Atlantic. There has been a distinct warming trend since 1990, and
Enfield et al. (2001) suggest that the AMO is entering a warm phase during which less than
normal rainfall is seen. How such a trend may impact freshwater input to Long Island Sound,
and hence buoyancy driven circulation between Block Island Sound and the Offshore Ocean
SAMP area, is not known. For instance, Merriman and Sclar (1952) found that dominant year
classes of butterfish, weakfish and cunner were produced in June and July of 1944, and that
the reproductive success of all three species was correlated to high salinity water in Block
Island Sound, which was the result of lower than normal freshwater input to Long Island
Sound. Further research is needed to better describe the role of freshwater input and seasonal
salinity patterns on the ecology of the Ocean SAMP area, and possible impacts to the ecology
from changing precipitation patterns as a result of climate change. See Chapter 3, Global
Climate Change, for further discussion of changing precipitation patterns in the Ocean
SAMP area.
230.3.3. Stratification
1. While winds, tides, and circulation all promote the transport and mixing of water and the
constituents contained in it, water column stratification—because of differing water density
regimes at surface and at depth—plays an opposing role by setting up the physical conditions
that can limit or preclude vertical mixing. A stratified water column is vertically stable, and
promotes an accumulation of phytoplankton, which can then grow to bloom proportions
(Mann and Lazier 2006). Decomposition of plant matter in the bloom consumes oxygen, and
since stratification prevents vertical mixing, hypoxic or anoxic conditions can ensue, to the
detriment of marine life. Water column stratification—sometimes strong stratification—sets
up in both Rhode Island Sound and Block Island Sound, and over the Offshore Ocean SAMP
area as well; stratification appears to be highly seasonal. It has been suggested that Block
Island Sound, due to its more vigorous circulation and mixing regimes, is less prone to
stratification than Rhode Island Sound. However, observations suggest that strong
stratification can occur in either sound (Codiga and Ullman 2010). The onset of stronger
winds during the fall tends to break down stratification of the water column in all areas.
Further work is needed on this topic to clarify the onset and persistence of stratification
events, and to then begin exploration of impacts, if any, to the ecology of these ecosystems.
There are however, no reports of water column anoxia or hypoxia for Ocean SAMP waters.
2. Beardsley et al. (1985) report that the outer shelf and continental slope waters are stratified
on a seasonal basis—strong (e.g., stable and resistant to breakdown) stratification sets up
during summer months, but breaks down in the fall, with the water column remaining well
mixed throughout the winter. They found mixing of the water column to 200 m below
surface. Codiga and Ullman (2010) also find strong stratification of the water column during
the spring and summer, with stratification either weak (e.g., unstable and easily dispersed) or
absent during fall and winter, in both Rhode Island and Block Island Sounds. Based on this,
it can be noted that stratification appears to be a common, seasonal phenomenon throughout
the Ocean SAMP area.
3. Shonting and Cook (1970) found a distinct thermocline in Rhode Island Sound during a
survey in July of 1963; surface temperatures were 20°C and bottom temperatures less than
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 36 of 132
10°C; this is a significant difference and suggests strong stratification of the water column.
Shonting and Cook (1970) found the thermocline to be most pronounced on the southern side
of Rhode Island Sound, and much less pronounced near shore to the north. They further
suggest this might be a function of the tidal currents in areas near the mouth of Narragansett
Bay which would mix the water column. The thermocline was virtually eliminated by
decreasing temperatures and increasing winds during the fall. Codiga and Ullman (2010)
found stratification in the western region of Rhode Island Sound during spring months, and
again during most of the summer months as well. Water column sampling at four stations in
Rhode Island Sound (December 2002, between Block Island and Brenton Reef) found weak
stratification with a fairly homogenous water column with regard to temperature, salinity and
dissolved oxygen (U.S. Army Corps 2002). Dissolved oxygen concentrations in both surface
and bottom waters however, remained well above the criteria established for highest quality
marine waters, suggesting that hypoxia/anoxia may not be a condition typically associated
with stratification in the Ocean SAMP area.
4. Freshwater input from Long Island Sound sets up water column stratification just south of
Block Island. The area of stratified water expands northward during times of high river
discharge, but is seasonal in its nature and breaks down during summer months and/or times
of reduced precipitation/river flow. Williams (1969) found the water column to be well-
mixed during the winter, with temperatures 1–3°C. During summer months, a strong
thermocline developed, with surface water at 20°C and bottom water as low as 10°C.
O’Donnell and Houk (2009) note a seasonal cycle to salinity in Block Island Sound, but with
greater variability than that observed for water temperature. Figure 2.13 shows seasonal
averages for surface and bottom salinity in northwestern Block Island Sound. Times where
surface and bottom water salinity are near equal suggest intense mixing events, perhaps from
storms, that breakdown and eliminate water column stratification. Wide differences between
surface and bottom water salinity, particularly in those times where surface water salinity
decreases rapidly, suggest influxes of freshwater from Long Island Sound, with intensified
water column stratification a high probability (Figure 2.14). Codiga and Ullman (2010) found
winter stratification to be stronger in Block Island Sound than in Rhode Island Sound, largely
due to the freshwater influence of Long Island Sound outflow. They also found stratification
to be enhanced in eastern Block Island Sound during spring months, again because of the
influence of Long Island Sound outflow. In general terms, Codiga and Ullman (2010) found
stratification to be consistently the strongest in the western Ocean SAMP area, particularly
south of Block Island.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 37 of 132
Figure 2.13. Average annual surface and bottom salinity at a station in Block Island
Sound (CTDEP No. N3; between NW of BI, ¾ of the way to The Race; from O’Donnell
and Houk 2009). Periods where surface and bottom salinities are nearly equal suggest
mixing events, while rapid declines in salinity of surface waters suggests increased
freshwater input associated with increased runoff in rivers feeding Long Island Sound.
Figure 2.14. Surface water salinity during times of high freshwater discharge (left panel)
and low discharge (right panel; from O’Donnell and Houk 2009).
5. During times of low freshwater discharge into Long Island Sound, Ullman and Codiga
(2010) have observed intrusion of high salinity water at about 30 m depth in the water
column, finding the characteristics of this water to be consistent with those reported by
Linder and Gawarkiewicz (1998) for water found on the inside of the Continental Shelf,
about 100 km offshore. The impact of mid-depth, high salinity intrusion events on the
ecology of the area has not been studied, but suggests that a strong connection between
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 38 of 132
waters of the offshore Ocean SAMP area and Block Island Sound may result during times of
low flow from Long Island Sound.
230.4. Circulation
1. Circulation is a major force shaping the ecology of the Ocean SAMP area, being responsible
for the distribution of much of the flora and fauna found in Rhode Island Sound and Block
Island Sound. Planktonic organisms and planktonic life-cycle phases (e.g., fish eggs and
larval crustaceans) are at the mercy of circulation patterns for dispersal and to take them to
suitable settlement sites. Circulation determines areas of food concentration, which in turn
largely determines where predators will congregate to feed.
2. Circulation patterns in Rhode Island and Block Island Sound are influenced by temperature
and salinity differences in the water column, tidal ebb and flood, and wind shear. Buoyancy
driven circulation—circulation that occurs based on the relationship between water
temperature and salinity, which together define the density of water, and the differences in
water density both vertically and laterally—makes an important contribution to the mean
circulation on seasonal and longer timescales (Codiga and Ullman 2010). Tidal ebb and flood
is considered to play an important role in creating turbulence and in mixing the water
column, while wind-driven currents play a significant role on timescales of a day to several
days, particularly during winter in association with storms, but also in summer due to the
diurnal sea breeze. For instance, westerly winds during summer increase the exchange of
water between Block Island Sound and Rhode Island Sound in the area between Block Island
and the Rhode Island coastline. Winter winds on the other hand, which are predominantly
from the northwest and stronger than summer winds, promote water column mixing rather
than increased water exchange (Gay et al. 2004). This is further supported by the direct
observations of Codiga and Aurin (2007) who found the volume exchange of water between
Long Island Sound and Block Island Sound to be weakest during winter months.
3. Observed tidal circulation patterns vary considerably between Rhode Island Sound and Block
Island Sound. Rhode Island Sound appears to behave as an appendage of the Offshore Ocean
SAMP area region, while Block Island Sound behaves, to a large degree, more as an arm of
Long Island Sound. Because of significant dynamic interaction with Long Island Sound, it is
generally considered that Block Island Sound has a more intensive mixing and circulation
regime than Rhode Island Sound (Codiga and Ullman 2010). Codiga and Aurin (2007),
through direct observations, found that exchange flow between Long Island Sound and Block
Island Sound is strongest during summer months. Figure 2.15 (Mau et al. 2007; He and
Wilkin 2006) shows graphical results of two separate circulation studies, one in Block Island
Sound and the other in Rhode Island Sound. The panels are joined to provide a view of the
general current patterns of the Ocean SAMP area, though scales differ and actual velocities
are not directly comparable; they do however show the relative vigor of the circulation in
both systems. Current velocity is seen to be vigorous throughout most of Block Island Sound,
particularly in the west where influence of The Race is strong, while the majority of the area
of Rhode Island Sound is under the influence of relatively mild current speeds, except to the
east where it interacts with Vineyard Sound and Nantucket Shoals. Impacts of this major
difference between the sounds regarding their ecology are not known. While significant
differences exist between Rhode Island Sound and Block Island Sound, these water bodies
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 39 of 132
are connected and do interact with each other, and with the Offshore Ocean SAMP area
region.
Figure 2.15. Differences in tidal circulation velocities between Rhode Island Sound
(RIS) and Block Island Sound (BIS), showing Block Island Sound to be more vigorous
and dynamic than Rhode Island Sound. Velocity is greatest over shallow areas and at
constricted areas. Note different scales; this does not allow direct comparison between
the two diagrams. [VS=Vineyard Sound; NS=Nantucket Shoals]
4. Available data suggests that there is a deep flow into Block Island Sound from the east,
running between Point Judith and Block Island, and that a cold current of water flows into
the eastern portion of Rhode Island Sound from Nantucket Shoals (Codiga and Ullman
2010). The deep portion of the flow entering from Nantucket Shoals moves largely westward
into Block Island Sound while its surface component flows largely southward, joining Long
Island Sound flow to form a major coastal current that moves to the southwest, away from
the region, over the Offshore Ocean SAMP area and into the Mid-Atlantic Bight (Codiga and
Ullman 2010; Beardsley and Boicourt 1981). Kincaid et al. (2003) and Riley (1952) found a
generally tending westward flow between Block Island and the Rhode Island coastline that
moved into Block Island Sound and could perhaps interact with Long Island Sound water.
5. Based upon findings presented previously, and upon results of their own modeling and
research, Codiga (2009) have developed a schematic that shows circulation transport
pathways in Rhode Island Sound and Block Island Sound (Figure 2.16). They find minor
interaction between Rhode Island Sound and Narragansett Bay, Buzzards Bay and Vineyard
Sound both at surface and at depth. Deep flow from Point Judith, moving westward along the
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 40 of 132
Rhode Island shore and into Block Island Sound is moderate, as are return flows at surface
from Block Island Sound into Rhode Island Sound around the north side of Block Island.
Moderate flow at the surface (into Block Island Sound) and strong flow at the bottom (into
Long Island Sound) is seen through The Race. Moderate flows are seen at depth coming off
the Offshore Ocean SAMP area into both Rhode Island Sound and Block Island Sound, with
strongest cross-shelf deep flow occurring into Rhode Island Sound along its eastern portion;
Codiga (2009) concede that there is limited information for this section of Rhode Island
Sound, and that further study is needed. Strong surface flows are observed moving water out
of both sounds, generally in a southwestward direction parallel to the south shore of Long
Island. Surface water transport out of both sounds and south following the coast of Long
Island is a major pathway for water in the Ocean SAMP area to move into the Mid-Atlantic
Bight ecosystem.
Figure 2.16. Schematic of hypothesized water flow at surface and at depth in the Ocean
SAMP area (from Codiga 2009).
6. While Figure 2.16 shows overall patterns of circulation, Figure 2.17 shows a summary
schematic diagram of surface and bottom flows on a seasonal basis, based upon best
interpretation of observations and model output. Fall and winter show dominant offshore
flow out of Rhode Island Sound, with a reversal during spring and summer months; this
reversal could promote inshore transport of larval forms produced during winter/spring
spawning events. Block Island Sound shows continuous interchange with all adjacent
waterbodies, though the interchange is most vigorous in spring and summer when Long
Island Sound influence is the greatest. Interaction between Block Island Sound and Rhode
Island Sound is year round, but most intense in spring and summer when freshwater input
from Long Island Sound intensifies overall circulation in the Ocean SAMP area.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 41 of 132
Figure 2.17. Schematic summary, based on observations and model outputs, of currents
and hydrography in the Ocean SAMP area; size of arrow indicates magnitude of the flow
(from Codiga and Ullman 2010). Histogram inserts show detail of temperature, salinity
and density at various sites.
230.4.1. Block Island Sound
1. Circulation in Block Island Sound is largely influenced by interaction with Long Island
Sound and the volume of freshwater being received by its major rivers, the Connecticut and
Thames, which provide 80% of the freshwater inflow (Gay et al. 2004). The main portal for
exchange between Block Island Sound and Long Island Sound is a narrow, deep channel
called The Race, which approaches depths of 100 m (Edwards et al. 2004; Gay et al. 2004).
Because of the narrowness of the opening, water velocities can exceed 2.68 m sec-1 (5.2
knots) on the ebb tide and 2.06 m sec-1 (4.0 knots) on the flood (Savard 1966). The Race is an
important feature as it allows for the exchange of warmer, nutrient rich, low salinity water
from Long Island Sound with colder, saltier water from the Continental Shelf. Codiga and
Aurin (2007) suggest that the approximate mean annual volume transport between Long
Island Sound and Block Island Sound through The Race is 24,000 m3 sec-1 (Figure 2.18). The
transport is also seasonal in nature, responding to increased freshwater inflow during spring
and early summer months. Because of the intense interaction with Long Island Sound, the
western portion of Block Island Sound can be considered well-mixed as far as 5–10 km out
onto the Offshore Ocean SAMP area region, and to a depth between 20 and 40 m (Edwards
et al. 2004). There is a second point of interaction between Block Island Sound and Long
Island Sound through an opening between Napatree Point (RI) and the eastern tip of Fishers
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 42 of 132
Island (NY; Figure 2.1) though water depth and current velocities are considerably less than
those observed in The Race.
Figure 2.18. Seasonal volume transport from Block Island Sound into Long Island Sound
(from Codiga and Aurin 2007).
2. Upon leaving The Race, shallow flow tends southwestward towards the opening to Block
Island Sound between Montauk Point and Block Island, with a peak flow of 10–25 cm s-1
(Figures 2.15 and 2.16; Ullman and Codiga 2004). This flow is deflected westward along the
south shore of Long Island by the Coriolis force, where it moves southward to mingle with
southern waters of the Mid-Atlantic Bight ecosystem. This flow is seasonally stratified;
strongly so during late spring and early summer due to estuarine flow driven by freshwater
input to Long Island Sound. During the spring freshet (e.g., snow melt plus spring rains) this
flow is significant, and is referred to as a “jet” which can be detected 5 km south of Montauk
Point (Ullman and Codiga 2004). Codiga (2009) hypothesized reports an annual mean
volume flow out of Block Island Sound at surface of 24,000 m3 sec-1 onto the Offshore
Ocean SAMP area, with a bottom water return from the Shelf into Block Island Sound of
10,000 m3 sec-1.
3. A sharply delineated boundary, or sharp gradient (e.g., a front), is observed south of Block
Island where lower salinity estuarine waters meet saltier continental shelf waters (Edwards et
al. 2004; Ullman and Cornillon 2001). The front may represent the outer boundary of
estuarine influence from Long Island Sound on the Offshore Ocean SAMP area (Ullman and
Codiga 2004; Ullman and Cornillon 2001). The front is readily noted by a temperature
discontinuity, and is seasonal in its nature. Figure 2.17 shows the seasonality of the front;
offshore in winter then moving north and intensifying in spring with a strong presence off
Block Island during summer months. During summer, the front is strongly set and is often
observed to extend from the region northeast of Block Island southwestward, 15–20 km
southeast of Montauk Point (Figure 2.19; Edwards et al. 2004; Kirincich and Hebert 2005;
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 43 of 132
Codiga 2005). The influence of this front on the ecology of the sounds is not well known.
However, fronts are areas of high biological activity due to nutrient mixing across water
masses, which stimulates increased primary production (Mann and Lazier 2006); increased
primary production often leads to increased secondary production (Munk et al. 1995).
Commercial and recreational fishermen actively seek out the location of the front to help
locate specific species and/or areas of greater fish abundance, suggesting the front either acts
as an area of food concentration, or as an area of thermal refuge, or both. Roff and Evans
(2002) note that distinct, special oceanographic processes that occur at local scales (e.g., a
front) create distinctive habitat that is attractive to fish. Worm et al. (2005) correlated sea
surface temperature gradients to increased tuna and billfish diversity. Further description of
the ecological importance of oceanic fronts can be found in Mann and Lazier (1996).
January
July
Figure 2.19. Probability of sea surface temperatures occurring along the “front”.
Averaged 1985-1996. The front is narrow, stable in summer; diffuse, unstable in winter
(Ullman 2009).
4. Tidal exchange rates for Block Island Sound and the Offshore Ocean SAMP area have been
estimated at a rate of 2.9 x 105 m3 s-1 (Codiga and Rear 2004), 3.5 x 105 m3 s-1 (Kopplman et
al. 1976, using a tidal prism approach) and 6.3 x 105 m3 s-1 (Kenefik 1985 using a numerical
modeling approach). Williams (1969), at a station located 40 miles south of Fishers Island,
measured average tidal flows of 0.75 m s-1 on the flood tide (1.46 knots), and 0.55 m sec-1 on
the ebb tide (1.07 knots), with a maximum recorded flow of 1.08 m s-1 (2.1 knots; tidal phase
not stated). The volume of water exchange with the Offshore Ocean SAMP area is therefore
significant, though velocity of exchange is considerably less than experienced near shore.
The exchange promotes the influx of offshore and southern species into the Ocean SAMP
area, as well as promotes dispersal of Block Island Sound species (e.g., planktonic
organisms) into offshore waters.
230.4.2. Rhode Island Sound
1. Circulation in Rhode Island Sound is influenced by interaction with Narragansett Bay
through the East and West Passages, Buzzards Bay and Vineyard Sound, Nantucket Shoals,
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 44 of 132
Block Island Sound and the Offshore Ocean SAMP area. The East Passage, which has an
average depth of 18 m and a maximum depth of 40 m, is the deeper of the two connections to
Narragansett Bay and experiences current flows of 20,000 m3 sec-1 on the flood tide and
30,000 m3 sec-1 on the ebb (Kincaid et al. 2003). The West Passage sees current speeds about
60% less than those for the East Passage, on either tide.
2. Shonting (1969) observed bottom currents in Rhode Island Sound flowing at rates of 8–12
cm sec-1 and showing little overall variability. Surface currents were found to flow at rates of
15–35 cm sec-1, with an average speed of 22 cm sec-1 and with great variability. Surface
flows tended towards the west-southwest at speeds of 12–14 cm sec-1, while bottom flows
showed a rotary motion in anti-cyclonic swirls that provided little net transport. The rotary
motion suggests that bottom water does not effectively aid in benthic transport. However,
Shonting (1969) notes that there was no expression of the typical summer sea breeze during
the time frame of their survey, and they suggest this may have been an influencing factor
which may not be typical of the season. Kincaid et al. (2003) and Hyde (2009), both reported
cyclonic flow in Rhode Island Sound, and that it was seasonal in nature. Such a circulation
pattern could have significant influence on the ecology of that area of Rhode Island Sound,
though further study to verify and describe this phenomenon in greater detail would be
needed.
3. First (1972) measured bottom currents at a station located on Cox Ledge in Rhode Island
Sound, in 54 m water depth, and found that current flows were generally to the northeast or
to the southwest, and that the bottom currents tended to flow according to bottom
topography. First (1972) measured a maximum velocity of 20 cm sec-1 and an average
velocity of 5 cm sec-1 along the bottom in that area, and found these flows to be considerably
less that those measured at a station just off Point Judith (average velocity of 21 cm sec-1 at
15 m water depth).
4. Cook (1966) notes that during the spring there is a non-tidal surface drift to the east and the
northwest in Rhode Island Sound, with a northwesterly tending bottom non-tidal drift. Cook
(1966) also found a strong westerly flow running between Block Island and Point Judith (see
Figure 2.16). During summer, Cook (1966) found a north tending non-tidal drift at the
surface, and a northwest bottom drift. During autumn there was southerly drift at surface, but
to the north on bottom. Annual average drift rates at the surface were observed to be 2–16 cm
sec-1, while on bottom they tended between 0.1 and 3 km day-1 (0.1–3.0 cm sec-1).
5. Kincaid et al. (2003) hypothesized upwelling of Rhode Island Sound water in the area of
Brenton Reef, and that this water was then advected (movement in a horizontal direction)
into the East Passage of Narragansett Bay. Such an exchange could be an important source of
nutrients to lower Narragansett Bay, but needs to be further quantified to determine if and
how it influences the ecology of Narragansett Bay.
6. Kincaid et al. (2003) also found a distinct, significant flow during summer time in the eastern
portion of Rhode Island Sound that moved to the west, and then southwest, following the
coast of Rhode Island (Figure 2.20). Riley (1952) noted a similar westward flow into Block
Island Sound between Point Judith and Block Island, as have Codiga and Ullman (2010).
During winter months this flow continued, but at a much diminished rate. Kincaid et al.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 45 of 132
(2003) suggest that a seasonal cyclonic gyre exists in Rhode Island Sound, and that this gyre
has significant influence upon dynamic exchange with Narragansett Bay. While a cyclonic
gyre the size of Rhode Island Sound is consistent with flow counterclockwise around its
periphery, the analysis of model output by Codiga and Ullman (2010), and of current
observations in Ullman and Codiga (2010), have both demonstrated that along the southern
edge of Rhode Island Sound the flow is westward, which contradicts the idea that flow closes
in a distinct gyre as originally suggested by Cook (1966).
Figure 2.20. Seasonal, tidally averaged volume transport between Narragansett Bay and Rhode
Island Sound (from Kincaid et al. 2003) White arrows are for summer flows and black for winter;
size of arrow is relative to volume of flow; units are m3 sec-1.
7. While Signell (1987) found modeled interaction between Rhode Island Sound and Buzzards
Bay to be weak, there is intermixing with offshore water in the Cape Cod region. Hicks and
Campbell (1952) noted a net flow of water from Buzzards Bay into Rhode Island Sound; in
winter the tongue of water was colder than offshore waters. They found a surface water
salinity minima of 29.5‰ at the mouth of the West Passage, and a maxima of 32.9‰ on the
Offshore Ocean SAMP area region; bottom waters ranged from 31.2–33.0‰. A coastal
current flows south of Block Island Sound, entering from the northeastern region of Rhode
Island Sound (Figure 2.16; Kincaid et al. 2003). This current flow is at least partially due to
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 46 of 132
water coming around the arm of Cape Cod, moving through Nantucket Shoal and into Rhode
Island Sound (Figure 2.7 and Figure 2.16; Shcherbina and Gawarkiewicz 2008).
Furthermore, work by He and Wilkin (2006) show current flows moving around the south
side of Martha’s Vineyard and then into Rhode Island Sound, providing a clear path for water
from the north into Rhode Island Sound and the Ocean SAMP area.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 47 of 132
Section 240. Chemical Oceanography
1. Over the course of the millennia of its existence, planet Earth has come to a form of
equilibrium with the “chemical soup” contained in its soils, waters, oceans, atmosphere, and
biota. Nearly all the elements that can be found in “the soup” are essential to sustaining life,
though generally in modest quantities and often only in trace amounts and all are
continuously recycled through biological, chemical, physical, and geological processes.
2. Toxins are important limiting factors to productivity. In trace amounts, toxins are generally
not problematic, but at higher concentrations can lead to chronic or acute symptoms that
reduce quality of life for effected organisms, and/or create more serious impacts, such as
increased mortality or alteration of reproductive potential.
3. Existing studies do not suggest that toxins are problematic in the benthic sediments of
impacted sites in Rhode Island Sound; there are no reported impacted sites (e.g., dredged
materials disposal) for Block Island Sound. Since all sources of toxins are anthropogenic and
are of external origin (e.g., accidental spill, purposeful placement), it would not be
anticipated that the sediments in either ecosystem pose toxic threats to biota or to the
ecosystem at large.
240.1. Nutrients
1. Nutrients are critical to the growth of plants, and in the marine environment nitrogen is
generally the most critical nutrient as it is often to be found in limiting quantities and thus
sets limits to growth. Nutrients, critical elements for sustaining life, are recycled within the
ecosystem. Nutrient dynamics are often complicated by biological uptake, as well as
interaction with the benthos both biologically and physically, and can be difficult to
comprehend even in well-studied ecosystems. Overall, there has been little work completed
on nutrient dynamics in either Block Island Sound or Rhode Island Sound, and what has been
done has often been conducted close to shore and/or several decades ago. This is an area
where further research work is needed since nutrient dynamics set limits to primary
production, which in turn strongly influences ecosystem make up and function.
2. Ramp et al. (1988) report a net transport of shelf water from Nantucket Shoals to the west,
eventually flowing to the Mid-Atlantic Bight as described previously. Ramp et al. (1988)
suggest that 39–53% of the nitrogen reaching the Mid-Atlantic Bight moves in this flow.
Given that there is interaction between the waters flowing south along the shelf (Loder et al.
1998; Figure 2.7 and Figure 2.16) and the waters of the Ocean SAMP area, particularly
Block Island Sound, this may be an important source of nitrogen to Rhode Island Sound and
Block Island Sound, though further study is needed.
3. While often more limiting in freshwater systems, phosphorus is a required nutrient for
growth of plants in marine systems. Riley (1952) found phosphate concentrations at a
maximum in mid-winter in Block Island Sound, with a rapid decline during the time of the
spring phytoplankton bloom; it was suggested that phosphate was not a limiting nutrient in
Block Island Sound waters. Similar work has not been published for Rhode Island Sound.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 48 of 132
4. Staker and Bruno (1977) sampled nutrients in Block Island Sound (Table 2.1). The stations
were relatively close to shore (south side of Long Island and near Gardners Island) and in
shallow water (15 m and 6.5 m, respectively), so it is unclear how representative these
measurements might be for more central areas, such as between Block Island and Montauk
Point. These researchers conclude that overall, nutrient concentrations were highest in the
autumn and near zero/undetectable in late spring and early summer. Phosphate was found not
to be a limiting nutrient to growth in the Block Island Sound ecosystem and in agreement
with Riley (1952); nitrate and nitrite may become limiting seasonally, mainly during the time
period of late May to early July.
Table 2.1. Nutrient concentrations measured in Block Island Sound (Staker and Bruno
1977).
Nitrate (NO3)
Concentration
Time
10 µM
Nov to Jan
3–4 µM
March and April
Nitrite (NO2)
6 µM
October
0 µM
Summer
4–5 µM
September
Orthophosphate (PO4)
1.8 µM
November
1–2 µM
July
5. Oviatt and Pastore (1980) sampled the concentration of various nutrients in Rhode Island
Sound (Sta.16 at the mouth of Narragansett Bay; Sta.17 just outside the mouth) on a seasonal
basis (Table 2.2). Unfortunately not all measures can be readily compared to those for Block
Island Sound because of timing differences, but orthophosphate (PO4) concentrations appear
to be similar for the one area of overlap for samples taken in November (Table 2.1), and are
in general agreement with one another.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 49 of 132
Table 2.2. Nutrient concentrations measured in Rhode Island Sound by Oviatt and
Pastore (1980; estimated from graphs in original report–highest concentration within a
time span is given).
Concentration (µM)
Ammonia (NH3)
Sta. 16
Sta. 17
Time
0
Jan–May
1
1.5–2
Jun–Aug
3–4
2–2.5
Nov–Dec
Nitrite + Nitrate (NO2 + NO3)
6
6
Jan
1–2
5
Feb
0.5
0.5
Mar
5
4
Apr
0
1–2
May–Aug
6
6
Nov
12
10
Dec
Orthophosphate (PO4)
1–2
1–1.5
Jan–Aug
1.5
1.5–2
Nov–Dec
Silicate (SiO4)
1.5
1.5
Feb–Mar
7
4
Apr
4
5
May–Jun
16
18
Jul
6–7
10–11
Aug
7
8
Nov
20
18
Dec
6. The nutrient data are too meager to draw any firm conclusions regarding the trophic status
(e.g., eutrophic, oligotrophic) of the Ocean SAMP area. This is an area where further work is
needed. However, slightly lower primary production measures (see Section 250.1.1) than is
seen for adjacent waters suggests that perhaps nutrient availability may be limiting.
240.2. Toxins
1. The Ocean SAMP area is not industrially developed, does not receive direct discharges of
municipal or industrial wastes, and is not the regular recipient of refuse or other disposed
materials. As such, toxins in the environment would be expected to non-problematic in the
Ocean SAMP area. However, Rhode Island Sound has received dredged materials from
Narragansett Bay on several occasions, and was the site of an oil spill in the 1990s. Dredged
materials often contain various contaminants that in general, will be limited in their realm of
impact to the containment site once the disturbance from placement has diminished.
Furthermore, contaminants would mainly be restricted to the sediments and impacts would
tend to be restricted to the benthos. If benthic sediments are disturbed however, whether
through natural (e.g., turbulent mixing due to storm activity) or human induced means (e.g.,
seafloor disturbance), then contaminants could be put into suspension in the water column
where they could directly impact the pelagic ecosystem, or be dispersed and settle in other
areas, possibly impacting the benthic ecosystem. Dredge materials disposal sites in Rhode
Island Sound are at a depth where bottom sediment could be mobilized during hurricane
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 50 of 132
events (e.g., see Section 230.1; First 1972). It is also possible that sediment reworking by
infaunal invertebrates (e.g., living in the sediments) could mobilize toxins into the food web
where bioaccumulation could become problematic. However, based upon toxicity testing at
both dredged materials disposal sites and oil spill impacted areas, it appears that
environmental toxins are not a significant threat to the Ocean SAMP ecosystem.
2. The Rhode Island Sound Disposal Site (RISDS), designated in December 2004 and located in
Rhode Island Sound, has been used for the disposal of dredged materials. The 3.24 km2 site,
with water depths from 36 to 39 m, is located at 41° 13.850' N, 71° 22.817' W (NAD 83;
Figure 2.21). The site lies approximately 21 km south of the entrance to Narragansett Bay
and is within the Separation Zone for Narragansett Bay Inbound and Outbound Traffic
Lanes. Approximately 3.4 million m3 of sediment from the Providence River (primarily from
the Federal Navigation Project) were disposed of at this site.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 51 of 132
Figure 2.21. Dredged materials disposal sites, and location of the North Cape oil spill.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 52 of 132
3. The Brenton Reef Disposal Site (Figure 2.21) has been extensively used for the disposal of
dredged materials from Rhode Island waters, mainly from the dredged navigation channel in
Narragansett Bay, with the last dumping at the site occurring in the 1970s. Battelle (2002a)
conducted a study to test toxicity levels at the Brenton Reef and Rhode Island Sound disposal
sites, and 2 stations between the two sites, and found that species composition among the
various sites, both inside and outside of the dredged materials disposal areas, were not
significantly different from one another, suggesting that benthic community recovery from
the disturbance event has occurred.
4. Measurement of metals concentrations (Ag, As, Cd, Cr. Cu, Ni, Pb, Se, Zn) in the water
column at four sample stations (same stations as those for Battelle 2002a) in Rhode Island
Sound found detectable levels, but at concentrations that were well below ambient Rhode
Island Department of Environmental Management water quality criteria for toxic pollutants
(U.S. Army Corps 2002). Similar results were found for organic and inorganic contaminants
(PCBs, Pesticides, Hg) at the four sample sites.
5. On January 19, 1996, the barge North Cape spilled more than three million liters of No. 2
fuel oil, a relatively light, readily aerosolized petrochemical, into Rhode Island Sound off
Matunuck (Figure 2.21). The plume of oil moved to the east with the greatest impact being
seen in the area around Point Judith. Studies by Ho (1999) showed that toxicity in the
sediments at a heavily impacted site were small (3% ± 6% mortality for the amphipod
Ampelisca abdita) after nine months. It is not clear if hydrocarbon concentrations occur at
levels of concern in the sediments at this point in time, though it seems unlikely that toxicity
levels would be of concern given the time that has elapsed since the spill occurred.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 53 of 132
Section 250. Biological Oceanography
1. The unique geological, physical, and geographic characteristics of the Ocean SAMP area
provide conditions for making it suitable to a suite of organisms spanning all trophic levels.
Living phytoplankton and other photosynthetic organisms are limited to the light-penetrated
upper layers of the water column where they convert sunlight into organic matter.
Zooplankton convert phytoplankton into animal matter (e.g., protein) which fuels upper
levels of marine ecosystem food webs from bait fishes to apex predators. Microbes are
responsible for much of the decomposition of dead organisms, recycling nutrients and
making them once again available for uptake by plants and animals both in the water column
and the benthos.
2. Primary production takes place in the presence of light, and therefore plants are limited to the
sunlit layer of the water column (e.g., the photic zone). Depth to which light can penetrate the
water column is therefore an important factor in production. Ayers (1950) took water clarity
readings in Block Island Sound using Secchi disks; measures of 4.3 m were found near
Mount Prospect on Fishers Island and 6.1 m near Great Salt Pond during winter months.
During summer, Secchi depths at the same stations were 2.4 m near Fishers Island and 4.6 m
off Great Salt Pond. Secchi disk readings were taken in Rhode Island Sound during the
months of February and March by Hicks and Campbell (1952); average readings were 6 m
with a maximum of 10 m. In all cases transparency decreased with closeness to shore.
Decreased transparency in shallow waters close to shore may be due to increased
particulates, nutrients and/or primary production in the water column. This suggests a photic
zone of 10 m or less, with light penetration decreasing seasonally during summer months.
3. Richardson and Schoeman (2004), based on trends observed in the Northeast Atlantic Ocean,
note that warming waters have tended to increase phytoplankton standing stock in cold
waters, but decreased it in warmer waters. It is not clear, given that the Ocean SAMP area
overlaps two distinct bio-regions, how warming waters due to climate change will impact
phytoplankton populations, and if any impact would be in a positive or negative direction.
250.1. Plankton
1. There appear to be correlations between phytoplankton species composition in Narragansett
Bay and Rhode Island Sound, though more work is needed to prove and clarify that
correlation, as well as to research trends for species shifts over time. Recent findings of
Nixon et al. (2010) suggest that surface waters of Rhode Island Sound contain more
phytoplankton than those of Block Island Sound, though in summer when the water column
is stratified this relationship appears not to hold; this pattern does not hold for primary
production (see 250.1.1). Primary production is seasonal in the Ocean SAMP area, and
production values are generally similar to though slightly lower than those of adjacent areas,
which agrees with findings of Nixon et al. (2010). As is noted for Narragansett Bay, Rhode
Island Sound appears to be experiencing a less consistent winter–spring phytoplankton
bloom, though again more research is needed to verify and clarify this observation, and
define its importance to the overall ecology of the area. Nixon et al. (2010) have found
evidence for a fall bloom in Ocean SAMP waters, a bloom which was not seen to occur in
Narragansett Bay. Zooplankton species composition was found to be seasonal, and heavily
influenced by change in salinity and/or temperature in the water column; distinct species
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 54 of 132
changes were noted in warm vs. cool years, dry vs. wet years. Influx of the ctenophore M.
leidyi had significant impact on the zooplankton community of Narragansett Bay, though
similar study has not been conducted in Rhode Island Sound so it is unclear if similar
interaction is occurring. Differences between Rhode Island Sound and Block Island Sound
regarding zooplankton control of phytoplankton stocks was suggested, but has not been
studied in a comparative sense, nor is it known if ctenophore outbreaks have influenced
zooplankton–phytoplankton interactions in Rhode Island or Block Island Sound. Very
preliminary comparison (Deevey 1952a,b; Kane 2007) suggests zooplankton dominant
species have not changed over the past 50 to 60 years, nor has the seasonality of at least some
dominant species. Rigorous analysis however, needs to be undertaken before this can be
stated with any degree of surety.
2. Plankton is the collection of organisms that live in the water column and are subject to
oceanic currents for their distribution. The organisms making up the plankton range from
microscopic plants and animals to larger organisms with limited mobility, such as jellyfishes.
The plankton makes up a crucial source of food for marine ecosystems, and in general, forms
the foundation of marine food webs.
3. Since the distribution of plankton is determined by the movement of oceanic water masses
via current flows, tidal movement and wind-induced flow, understanding plankton
distribution can be simulated through circulation models and/or observed circulation patterns
(see Section 230.4). The generalized schematic of circulation in the Ocean SAMP area
(Figure 2.16) may provide a reasonable first-order estimate for probable plankton transport
pathways. Other forces, wind in particular, will play a role in transport at smaller/local scales
within the larger Ocean SAMP area.
4. Seventy-five species were recorded during a 1954-1955 survey of phytoplankton (Smayda
1957); nine diatoms and four flagellates were found to account for 94% of the total
phytoplankton abundance in Narragansett Bay. Riley (1952) found nine genera constituted
98% of the total number of phytoplankton cells in Block Island Sound in 1949. While it is
not well known how closely species composition for phytoplankton matches between
Narragansett Bay and Rhode Island Sound, both studies show that in both locations the
majority of the overall “crop” consists of a relatively few species. However, recent changes
in the plankton dynamics of Narragansett Bay are related to climatic warming (Sullivan et al.
2008). Given the lack of recent data on phytoplankton species composition in the Ocean
SAMP area, it is not clear if change similar to that seen in Narragansett Bay is underway.
Changes in zooplankton composition (see Section 250.1.3) suggest a need for research in this
area.
250.1.1. Phytoplankton Productivity
1. Plants have the all-important function of trapping sunlight, a very abundant yet dilute form of
energy, and converting it into organic matter (in the form of plants) that is a more
concentrated (though less abundant) form of energy that then becomes the foundation for
most food webs. Measurement of plant production, referred to as primary production,
provides an indication of how fertile, or how much food is being produced, in a given area
and perhaps over a given unit of time. Primary production is often reported in units of mg m-3
(milligrams per cubic meter), which indicates the amount of organic plant matter produced
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 55 of 132
(dried to remove the weight of water, which is substantial) in a given area or volume of
water. Primary production is also often reported in units of g C m-2 day-1 (grams of carbon
per meter square per day), which is the mass of carbon (the basic building block of organic
matter) produced in a given area and over a given time span.
2. The New York Ocean Science Laboratory initiated a general survey of the physical and
chemical characteristics of Block Island Sound and adjacent waters with the intention of
creating a baseline data bank (Hollman 1976; Staker and Bruno 1977). Staker and Bruno
found chlorophyll a (the green pigment contained in primary producers) concentrations that
were highly seasonal, and varied from near zero to 9.94 µg l-1. The species Thalassiosira
nordenskioldii was numerically dominant in the samples, but Skeletonema costatum and
Ceratium tripos presented a larger biomass in the community. Of interest is that Staker and
Bruno (1977) found Ceratium tripos (a dinoflagellate) to be very abundant in the
phytoplankton community during their survey, while Riley and Conover (1967) only found
this species in 2 samples during their previous surveys. No causality for the difference was
stated. Staker and Bruno (1977) also found that Thalassiosira nordenskioldii was more
abundant than reported in previous surveys. It cannot be deduced from these limited data if a
change in the ecosystem occurred, or if the variability is due to small sample size, though it
does point to a need for new research and better knowledge in this area.
3. Riley (1952) found that phytoplankton abundance generally increased with depth to a
maximum at 10–20 m. Riley also noted a spatial trend towards reduced phytoplankton
concentrations with distance south; concentrations were half as much near Block Island than
they were near Watch Hill, and there was no indication of a bloom at the site south of Block
Island. Riley further noted that phytoplankton concentrations in Block Island Sound were
higher than those found to the east in Rhode Island Sound, or to the south in the Offshore
Ocean SAMP area. It is likely that the dynamic interaction with Long Island Sound promotes
higher primary production in this area, perhaps bringing additional nutrients from land-based
sources in Connecticut, though this has not been quantified.
4. Smayda (1973) reported net primary production of 300 g C m-2 yr-1 for Block Island Sound,
which he found comparable to Long Island Sound and Narragansett Bay, though less than
that found for continental shelf waters. Smayda (1957) noted that Skeletonema costatum
comprised 81.2% of the total phytoplankton population in lower Narragansett Bay, which is
on par with Riley’s (1952) estimate of 83.5% for this species. Outside of this pairing, there
was not good matching between the less abundant phytoplankton species in lower
Narragansett Bay and outside waters. Smayda (1957) suggested that Narragansett Bay might
be a source of phytoplankton for outside waters via the westward current flow from the
mouth of the bay towards Long Island Sound. If this is so, broad overlap of species would be
expected between Narragansett Bay and Rhode Island Sound, but this comparative research
has not been conducted. Given similarities between various former studies (e.g., Smayda
1957 and Riley 1952), and divergence or change in later studies (e.g., Smayda 1973), this is
an area where further research would be useful for improved understanding of relationships
between Narragansett Bay and Rhode Island Sound, as well as within the overall, larger
Ocean SAMP area phytoplankton community.
5. Hyde (2009), using ocean color remote sensing data, estimated phytoplankton average annual
biomass and productivity for the past 10 years for the Rhode Island Sound and Block Island
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 56 of 132
Sound area as 1.07 mg m-3. Primary production estimates for the Ocean SAMP area ranged
from 143 to 204 g C m-2 d-1 and were comparable to, though slightly lower than, primary
production measurements for nearby regions (Table 2.3). Sampling at four stations in Rhode
Island Sound found chlorophyll a concentrations of 6 to 9 µg l-1 (U.S. Army Corps 2002),
which is comparable to those noted by Staker and Bruno (1977) for Block Island Sound.
They are also consistent with oceanic systems and slightly lower than an average estimate of
phytoplankton production on continental shelves (Mann 2000), and are consistent with
Hydes’ assessment. Nixon et al. (2010) found that chlorophyll concentrations above 4.5 µg l-1
were unusual but more common in Rhode Island Sound than in Block Island Sound, with
most common concentrations ranging between 0.5 and 1.0 µg l-1. For Rhode Island Sound,
Nixon et al. (2010) found production over the span of October 2009 to April 2010 to be
between 86 and 91 gC m-2 d-1, and 87 gC m-2 d-1for Block Island Sound. Figure 2.22 shows
annual phytoplankton growth (via chlorophyll a) in the Ocean SAMP area over a decadal
span of time. While there is year-to-year variability, a general trend of increased production
closer to shore is apparent. Nearshore waters will be shallower, better mixed, closer to
nutrient sources, and warmer than offshore waters, all factors which promote increased
productivity. No trend over time is visibly apparent from this time series data set, though
statistical analyses are lacking to make any further judgment.
Table 2.3. Comparison of the range of primary production (g C m-2 d-1) in Ocean SAMP
waters with nearby ecosystems (adapted from Hyde 2009); production in the Ocean
SAMP area is comparable to, though slightly lower than, nearby coastal systems.
Ecosystem
Production
Reference
Ocean SAMP
143–204
Hyde (2009)
Narragansett Bay
160–619
Oviatt et al. (2002)
Massachusetts Bay
160–570
Keller et al. (2001); Oviatt et al. (2007); Hyde et al. (2008)
Cape Cod Bay
231–358
Hyde et al. (2008)
Boston Harbor
211–1087
Keller et al. (2001); Oviatt et al. (2007)
New York Bight
370–480
Malone and Chervin (1979)
Mid-Atlantic Bight
260–505
O’Reilley et al. (1987); Mouw and Yoder (2005)
Georges Bank
265–455
O’Reilley et al. (1987)
Gulf of Maine
260–270
O’Reilley et al. (1987)
6. The diatom Skeletonema costatum was found to be abundant in Long Island Sound,
comprising nearly 72% of the total population, but being almost nonexistent in Vineyard
Sound, suggesting a possible west-east gradient in abundance across the Ocean SAMP area
(Lillick 1937; Riley 1952). Riley (1952) found Skeletonema costatum, Thalassionema
mitzachioides and Rhizosolenia setigera to be dominant species, and that nine genera made
up 98% of the phytoplankton counted.
7. Staker and Bruno (1977) found 125 species of phytoplankton over the course of their 13-
month study; Bacillariophyta and Pyrrophyta were the most abundant groups, with
Chrysophyta, Chlorophyta, Cyanophyta and Euglenophyta well represented. Skeletonema
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 57 of 132
costatum was found to be the numerically dominant phytoplankton species, while
Thalassiosira nordenskioldii and Ceratium tripos were dominant regarding biomass. These
findings are consistent with those of earlier surveys noted above; there is however, little
contemporary comparable species data for the Ocean SAMP area, so current species
dominance is not known.
250.1.2. Phytoplankton Seasonality
1. Riley (1952) conducted 12 surveys during 1949 that counted phytoplankton cells and
analyzed plant pigments in surface waters. A phytoplankton minimum was seen in mid-
winter and mid-spring, with a bloom in February and smaller blooms during mid-summer.
Deevey (1952a) suggested that phytoplankton seasonality was driven by physical
oceanographic processes rather than by zooplankton grazing. The characteristics of
phytoplankton seasonal cycles in Block Island Sound appear to be common in neritic
temperate waters; a midwinter minimum, a small and early spring bloom, and a moderate
abundance during late summer (Riley 1952). Riley also found 80% of the phytoplankton
species to be either littoral or neritic species (see Section 250.1.3. for definitions).
2. Contemporary measures of primary production and chlorophyll a concentrations in the
Ocean SAMP area show fairly consistent peaks during late fall and early spring, with a
distinct and significant fall bloom (Figure 2.22). However, no clear, consistent winter-spring
bloom is seen (Hyde 2009), which is a deviation from historical observations. Rhode Island
Sound seems to be mimicking Narragansett Bay in its loss of a consistent annual winter-
spring diatom bloom; causes for this are not clear, but suggests that large-scale forces (e.g.,
changing climate) may be at work. Chlorophyll a concentrations and primary production
show a fairly consistent minimum during summer months, which is in general agreement
with nutrient availability patterns noted previously (Section 240.1).
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 58 of 132
Figure 2.22. Monthly averaged chlorophyll a concentrations, 1998 through 2007, in the
Ocean SAMP area (from Hyde 2009). There is distinct seasonality, as well as greater
phytoplankton growth nearshore where shallower water, increased nutrient availability,
and warmer waters all combine to improve growing conditions.
250.1.3. Zooplankton
1. Zooplankton are important components of marine ecosystems as they convert plant matter
(phytoplankton) into protein that then fuels higher trophic levels of the food web. Long-term
change in the zooplankton community of the Ocean SAMP area is not readily apparent based
on existing data, suggesting stability in this food web component.
2. Deevey (1952a) found that the zooplankton community of Block Island Sound was a mix of
oceanic (from beyond the continental shelf), neritic (from the continental shelf area), littoral
(from sheltered waters and bays) and estuarine species (from areas were salinity varies
widely over short periods of time). In essence, Deevey (1952a) considered the area to act as
an intermediary, or “mixing basin,” for various adjacent environments. It is possible that this
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 59 of 132
unique mixture of species may facilitate species interactions (predator-prey relationships,
competition, etc.) and alternative food-web structures that may not occur in other
environments, though this has not been studied.
3. This unique zooplankton community changes seasonally. Deevey (1952a,b) furthermore
found that there was a distinct zooplankton maxima that occurred in mid-winter, with
seasonal lows in early spring and again in late autumn. There was a seasonal progression
where native species (e.g., littoral species and larval forms of bottom invertebrates)
dominated the zooplankton community from January through July; then from August through
December the number of species doubled due to an influx of Atlantic Ocean water containing
myriad warm water, non-native species from farther south. Given current trends of warming
waters, such a phenomenon as this could be important in promoting an influx of southern,
warm water species to the Ocean SAMP area.
4. Species composition of the zooplankton changed with salinity (Deevey 1952a). For instance,
the copepod Centropages typicus was dominant in surface waters, but then its abundance
declined as salinity levels declined. During the 1945 and 1946 surveys, Deevey (1952a)
reported no midsummer zooplankton maximum (e.g., a population increase between spring
and fall minima) as a result of reduced salinity in Block Island Sound, which was noted at
both surface and at depth and was suggested to be a result of an increase in freshwater input
to Long Island Sound during that time. Increased water column stratification was also
observed over the same time frame as was the observed shift in composition of the
zooplankton community, though no causality was implied. The zooplankton community is
dynamic and changes with temperature and salinity changes, which in turn may influence the
presence and abundance of upper trophic level species in the area, though this has not been
studied.
5. Important types of zooplankton in Block Island Sound (in 1949) included copepods,
cladocerans, pelagic tunicates, larval forms of bottom invertebrates, and ctenophores
(Deevey 1952b). In another report, Deevey (1952a) describes some of the important
zooplankton assemblages and community members:
a. Copepods—Centropages typicus, a neritic species, was found year round in Block
Island Sound but responded negatively to declining salinity, with an apparent
threshold at 30‰. This species was a dominant community member throughout the
survey period. Centropages hamatus, a littoral/neritic species at the southern edge of
its range, was important over the course of the survey period. Acartia tonsa, a littoral
species very common in Narragansett Bay, became more abundant in Block Island
Sound waters during late summer as numbers of C. typicus declined. It is not known if
warming temperatures due to changing climate have altered the abundance of this
species in Block Island Sound.
b. Cladocerans—Podon leuckarti was found during late spring and comprised about 20%
of sample tows during that time. Podon intermedius was found during summer and fall
in varying numbers. Evadne normanni was found only in the later part of the study and
not in large numbers. However, this species appeared to favor lowered salinities and
could be an important community member under reduced salinity conditions.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 60 of 132
c. Other—Larval forms of Balanus balanoides (common barnacle) were common during
the winter and spring. Early larval forms of a Lysiosquilla stomatopod that appears to
be common but not well known for Block Island Sound, probably living a reclusive
life style in deep burrows, was common during late summer/early fall. Pelagic
tunicates were common during later summer, with various jellyfish developmental
stages abundant spring through summer. Various southern species that had traveled
north on the Gulf Stream, as well as northern species, were found in the tows but only
as stragglers and were considered unimportant in the zooplankton community overall.
6. Zooplankton can be voracious grazers on phytoplankton and are capable of limiting
production available for consumption by other species (as in Narragansett Bay; Riley 1952,
Martin 1965). Riley (1952) did not see any correlation between zooplankton grazing and
phytoplankton abundance, and therefore concluded that zooplankton grazing did not control
the size of the phytoplankton population at any time in Block Island Sound. Riley’s
conclusion however, was based on Deevey’s findings (1952a,b) for Block Island Sound, and
those may not apply to adjacent waters. Further research in this area could alleviate
confusion, and perhaps better define the role of zooplankton grazing on phytoplankton stocks
in the Ocean SAMP area.
7. There has not been much work published on the zooplankton of Rhode Island Sound, so a
sample station located at the mouth of Narragansett Bay is considered as a proxy for at least
that area where it meets Rhode Island Sound. Zooplankton abundance peaked in February,
April and July during surveys conducted 1959-1962 (Martin 1965). Later studies showed that
zooplankton abundance declined to almost zero in late summer and fall as seen in surveys
conducted 1972-1973 (Hulsizer 1976), though Martin (1970) found that Skeletonema
abundance declined coincident with an increase in the abundance of the ctenophore
Mnemioposis leidyi. Ctenophores can be voracious consumers of Skeletonema and other
zooplankton. Martin (1970) noted the importance of this ctenophore in controlling
zooplankton abundance, though this species was not noted to increase during Martin’s earlier
study (1965). Acartia tonsa, A. clausi and Pseudoclanus minutus were the major species of
zooplankton present in later surveys (Hulsizer 1976). Ctenophores have a strong, but
apparently inconsistent, influence on zooplankton abundance and composition in the Ocean
SAMP area.
8. Marine Resources Monitoring, Assessment and Prediction Program (MARMAP; Kane 2007)
zooplankton data collected at a suite of stations in Rhode Island Sound and Block Island
Sound between 1978 and 2007 provide a contemporary look, and show a seasonal
progression of dominant species (Table 2.4). The most abundant zooplankton types
throughout the year are copepods, which make up 82% of the total number of zooplankton
sampled in winter, 76% in spring, 63% in summer and 70% in fall. Species abundances
reported here are in general agreement with those of Deevey (1952a, b), suggesting no long-
term shift in dominant zooplankton species during the previous 50 to 60 years. Seasonal
shifts noted by Deevey (1952a; e.g., Acartia tonsa) also appear to have remained stable over
that same 50 to 60 year time frame.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 61 of 132
Table 2.4. MARMAP Ocean SAMP area zooplankton data collected since 1978 (Kane
2007). The number of stations sampled has decreased from a high of 28 (1980) stations to
11 stations (2007; lowest = 2 stations in 1998).
Percent of Total Number
Winter
Spring
Summer
Fall
Taxa
Common name
Jan-Mar
Apr-Jun
Jul-Sep
Oct-Dec
Centropages typicus
copepod
32.6
7.0
27.2
49.7
Pseudocalanus spp.
copepod
33.4
28.7
11.6
1.7
Temora longicornis
copepod
5.1
19.3
5.3
1.7
Appendicularia
free swimming tunicates
8.5
11.8
2.4
3.3
Calanus finmarchicus copepod
2.1
10.5
7.9
1.2
Penilia avirostris
cladoceran
0.0
0.0
13.9
12.3
Acartia spp.
copepod
1.1
1.7
5.0
8.1
Echinodermata
larvae of sea stars, urchins, etc.
2.0
0.1
8.1
4.7
Centropages hamatus
copepod
1.6
5.5
3.1
1.3
Paracalanus parvus
copepod
6.1
0.2
1.5
6.5
Salpa
tunicates
0.0
0.0
5.6
6.1
Gastropoda
larvae of snails, etc.
3.1
1.0
3.7
0.7
Evadne spp.
cladoceran
0.2
4.2
1.2
0.2
Acartia longiremis
copepod
0.3
2.7
1.6
0.2
Chaetognatha
arrow worms
0.9
1.6
1.5
1.9
Cirripedia
larvae of barnacles
2.9
2.6
0.0
0.1
Evadne nordmanni
cladoceran
0.0
3.1
0.3
0.4
9. At a scale of the Northeast U.S. Continental Shelf, trends for increasing total annual
zooplankton biomass since the early 1980s have been noted (NOAA National Marine
Fisheries Service n.d.). A species shift since 1990 has also been seen, with smaller-bodied
taxa becoming more prominent (Kane 2007). A shift in seasonality for some species, such as
Calanus finmarchicus, to expressing peak abundance earlier in the season, and holding that
peak further into the season was also observed. These trends are noted for the entire northeast
shelf region, and so it can be presumed that these apply to the Offshore Ocean SAMP area
region, though such change is not readily apparent based on existing data for the Ocean
SAMP area; robust study on this topic has not been undertaken however. Since zooplankton
are at the base of the food chain and a source of energy for myriad species, it can be expected
that temporal changes in zooplankton abundance and species composition may propagate up
the food chain influencing abundances of higher trophic level species.
250.1.4. Microbes
1. Microbial ecology is relatively unstudied in the Ocean SAMP area, though some work has
been undertaken in neighboring Narragansett Bay (Marston 2008; Staroscik and Smith 2004).
Those findings are presented here as a potential, though not proven, proxy for Rhode Island
Sound, given there is no other known information to consider. Further research is needed to
determine if the use of Narragansett Bay microbial communities as a proxy to Rhode Island
Sound is reasonable and correct.
2. Several studies suggest that bacterial and phytoplankton mortality due to viruses is
comparable to mortality due to zooplankton grazing, and if so, this could be an important
influence on community composition (Wommack and Colwell 2000; Brussaard 2004; Suttle
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 62 of 132
2005; Weinbauer and Rassoulzadegan 2004; Marston 2008). Viruses are known to be
abundant and diverse in productive coastal waters (Fuhrman 1999; Wommack and Colwell
2000; Weinbauer and Rassoulzadegan 2004; Marston 2008). Abundances of cyanophages
(viruses that infect cyanobacteria, namely Synechococcus in Rhode Island waters) are
comparable and exhibit similar seasonal patterns in Rhode Island Sound as are seen in
Narragansett Bay (Marston 2008), with viral abundance peaking during summer months first
in Rhode Island Sound, followed by a peak in Narragansett Bay. Furthermore, Richardson
and Schoeman (2004) suggest that warming marine waters, due to changing climate, may
initiate a shift from phytoplankton-based food webs to microbial-based food webs. Though
no published work on microbes in the Ocean SAMP ecosystem was found, it is important to
consider due to the potential to influence the amount of primary production available for
consumption by higher trophic level species (i.e., zooplankton, fish, shellfish).
3. Staroscik and Smith (2004) found a high correlation between temperature and bacterial
abundance, but that it was also seasonal, with abundance being highest in spring and reduced
in the fall. The peak of bacterial production, measured at 68 g C m-2 yr-1, was in late June and
early July, where it remained high until water temperatures began to decline in September.
Staroscik and Smith (2004) found it likely that temperature, grazing, viral lysis, and substrate
availability all play a role in bacterioplankton production. Their sample station was located in
lower Narragansett Bay, at the dock at the University of Rhode Island Graduate School of
Oceanography; it is not known how well the observed patterns translate to Rhode Island
Sound waters.
250.1.5. Fish and Invertebrate Eggs and Larvae
1. The ichthyoplankton of the Ocean SAMP area is rich and varied, showing strong seasonality
for various species, no doubt linked to reproductive cycles. Report of a circulation gyre in
Rhode Island Sound requires further research (see Section 240.1) to determine its influence
on the ecology of the area, and how this affects larval transport throughout the area and the
water column, if at all. There appear to be changes in the species found over time, but the
data were not collected in a fashion that promotes direct comparison, suggesting another
avenue for research, particularly in light of the impacts of climate change; more detailed
analysis of the MARMAP (Richardson et al. in press) data might provide improved
understanding of fish species shifts in the Ocean SAMP area (see Section 250.3).
2. Many fishes and invertebrates spend some portion of their life cycle as planktonic organisms,
with tides and ocean currents, as well as behavior dictating their vertical and horizontal
distribution. Spending time adrift in the plankton is an important life history strategy that
promotes dispersal of populations into new areas as well as improving the chance that some
larvae will settle in suitable habitat. For instance, rock crab larval forms can be advected tens
of kilometers over short time spans (Clancy and Cobb 1997).
3. The timing of reproduction generally coincides with conditions most favorable to a species
survival, whether it is seasonal winds that promote circulation patterns that concentrate food,
or water temperatures that best promote growth of larvae and juveniles. Alteration of the
pattern and/or timing of seasonal events can alter the abundance and/or distribution of
species. For example, changes in dominant copepod assemblages have been noted on both
sides of the North Atlantic Ocean with increasing water temperatures (Beaugrand et al.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 63 of 132
2002); corresponding patterns have been found for Atlantic cod (greater numbers of cod
during shifts to larger copepods and fewer cod during shifts to smaller-sized copepods;
Beaugrand et al. 2003; Hays et al. 2005).
4. It is interesting to note that Shonting (1969) observed bottom waters in Rhode Island Sound
that moved in a rotary fashion, providing little overall positive transport in any given
direction. Hyde (2009) also suggests the existence of gyre-like circulation in Rhode Island
Sound, and if so then this could restrict interaction with Narragansett Bay, though she found
that the probability of larval transport into Narragansett Bay from Rhode Island Sound was
directly related to proximity to the mouth of the bay. Modeled results by Codiga and Ullman
(2010) suggest that deep flow is weak but consistently onshore during fall and winter
months, and mainly east to west flowing during spring and summer (see Figure 2.16 and
Figure 2.17). Therefore, it is likely that larvae and eggs trapped in bottom waters may be
primarily contained in the gyre-like circulation of Rhode Island Sound mitigating transport
outside of the Ocean SAMP area, though this topic needs more focused study to draw robust
conclusions as it is unclear if a true gyre exists, as has been hypothesized.
5. Pfieffer-Herbert (2009) found that ichthyoplankton (fish eggs and larvae) may have
undergone a shift in species composition over time. Figure 2.23 suggests that the
Narragansett Bay–Rhode Island Sound interface area has seen a decrease in the bay anchovy
(Anchoa mitchellii) since the late 1980s, with none being found during surveys in the late
1990s. Cunner (Tautogolabrus adspersus) has increased in abundance over that same time
span; other species change has also occurred (e.g., other in Figure 2.23). Interestingly, Collie
et al. (2008) have noted a decrease in adult cunner in the same general area over the past 10–
15 year time span. Further work is clearly needed to update these findings with contemporary
data, and to relate these to changes in the fish community (see Section 250.3).
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 64 of 132
Gobiosoma
ginsburgi
Pseudopleuronecte
s americanus
Pleuronectes
ferrugineus
Other
Tautoga onitis
Tautoglabrus
adspersus
Anchoa mitchelli
12/89‐11/90
Tautogolabrus
adspersus
Anchoa spp.
Tautoga onitis
Ammodytes spp.
Other
Peprilus triacanthus
Stenotomus
chrysops
10/87‐9/93
Tautogolabrus
adspersus
Tautoga onitis
Citharichthys
arctifrons
Peprilus triacanthus
Paralichthys
oblongus
Urophysis chuss
Other
6/98‐7/98
Figure 2.23. Ichthyoplankton abundance at the mouth of Narragansett Bay/Rhode Island
Sound at various points in time (from Pfieffer-Herbert 2009).
6. Katz et al. (1994) found that modeled passive drift from the offshore Ocean SAMP area into
Rhode Island Sound would move lobster larvae towards shore, and that if active swimming
by the larvae were accounted for, the larvae could readily reach the shoreline (Figure 2.24).
Given this finding, it can be presumed that actively swimming larvae, though it would be
highly species specific, could utilize current flows in the Offshore Ocean SAMP area region
as an effective population dispersal mechanism to inshore habitats. Based on known current
patterns for Rhode Island Sound, this would be particularly true for areas located in the
eastern portion of Rhode Island Sound.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 65 of 132
Figure 2.24. Lobster larval transport from the edge of the Continental Shelf into Rhode
Island Sound and Block Island Sound (from Katz et al. 1994).
7. Merriman and Sclar (1952) conducted surveys of fish eggs and fish larvae in Block Island
Sound, and found a seasonal assemblage of species represented (Table 2.5). Mackerel and
weakfish were the most abundant species, and it was suggested these species spawn in Block
Island Sound. Pipefish, sea horse, brassy sculpin, lumpfish, wrymouth and goosefish were all
considered to be accidentals. Merriman and Sclar (1952) considered scup to have only
limited spawning area in Block Island Sound, and that tautog were generally a more inshore
species and less common to Block Island Sound waters. Hake and yellowtail flounder were
common, but the lack of eggs and larvae suggested that they spawn elsewhere. While fluke
were found, Merriman and Sclar (1952) noted this species was a more southerly spawner.
They also suggested that mackerel, cod, butterfish, weakfish and cunner were the only fish
with pelagic eggs that spawn in Block Island Sound with any regularity and abundance.
Silver, squirrel and white hake, and yellowtail flounder, were considered to spawn to the east
and southeast of Block Island Sound; tautog and windowpane flounder were suggested to
spawn inshore in shallow waters.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 66 of 132
Table 2.5. Seasonality of fish eggs and larvae in Block Island Sound (Merriman and
Sclar 1952).
Month
Eggs
Larvae
January
Cod
Herring, Long-horn sculpin
February
Cod
Cod, Long-horn sculpin
March
Cod
Cod, Long-horn sculpin
April
Mackerel
Lumpfish, Wrymouth, Cod, Long-horn
sculpin, Brassy sculpin, Hake, Yellowtail
flounder
May
Mackerel, Butterfish
Lumpfish, Cod, Hake, Yellowtail
flounder, Brassy sculpin, Mackerel,
Butterfish
June
Goosefish, Cunner, Butterfish,
Mackerel, Weakfish
Hake, Mackerel, Cunner, Butterfish,
Yellowtail flounder, Windowpane
flounder
July
Cunner, Butterfish, Weakfish
Sea horse, Pipefish, Hake, Windowpane
flounder, Yellowtail flounder, Scup,
Tautog, Whiting, Weakfish, Butterfish,
Cunner
August
Cunner, Butterfish, Weakfish
Hake, Yellowtail flounder, Butterfish,
Cunner, Whiting, Weakfish
September
Butterfish, Weakfish
Herring, Hake, Butterfish, Whiting,
Weakfish
October
Weakfish
Herring, Hake, Butterfish, Whiting,
Weakfish
November
Cod
Herring, Hake, Whiting, Fluke
December
Cod
Herring, Fluke
8. The Marine Resources Monitoring, Assessment and Prediction Program (MARMAP;
Richardson et al. in press) collected ichthyoplankton samples at a suite of stations in Rhode
Island Sound and Block Island Sound between 1978 and 2007. These data are presented in
Table 2.6, and show distinct seasonality with regard to species abundances. While there are
differences in sample area (Block Island Sound (Merriman and Sclar 1952) vs. Ocean SAMP
area (Richardson et al. in press)), there are distinct differences in the predominant species
sampled. For instance, sand lance (Ammodytes) is a species not mentioned in the Merriman
and Sclar (1952) survey, yet it is the most abundant winter species in the MARMAP data.
Cod, a very prevalent species in the Merriman and Sclar data, is not mentioned in the
MARMAP data. It would be of interest to undertake more specific treatment of the
MARMAP data, doing various analyses that would check for species shifts over time for
comparison to Pfeiffer-Herber (2009) findings, and to changes in fish abundances (see
Section 250.3). Further research is needed to explore differences and/or correlations between
these data sets, and to examine other variables that may be influencing these species shifts.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 67 of 132
Table 2.6. MARMAP (Richardson et al. in press) ichthyoplankton data collected since
1978. The number of stations sampled has decreased from a high of 28 stations (1980) to
11 stations (2007; lowest = 2 stations in 1998).
Percent of Total Number
Winter
Spring
Summer
Fall
Taxa
Common name
Jan-Mar
Apr-Jun
Jul-Sep
Oct-Dec
Ammodytes
sand lance
97.5
1.1
0.0
43.6
Scomber scombrus
Atlantic mackerel
0.0
72.9
0.1
0.0
Urophycis
hake
0.0
0.0
25.1
4.6
Tautogolabrus adspersus
cunner
0.0
0.7
26.8
0.0
Citharichthys arctifrons
Gulf Stream flounder
0.0
0.0
19.0
1.8
Paralichthys dentatus
summer flounder/fluke
0.0
0.0
1.5
23.1
Merluccius bilinearis
silver hake
0.0
0.9
7.8
6.1
Limanda ferruginea
yellowtail flounder
0.2
15.8
0.1
0.0
Scophthalmus aquosus
windowpane flounder
0.0
3.4
1.5
4.3
Peprilus triacanthus
butterfish
0.0
0.0
5.1
0.3
Etropus
smallmouth flounder
0.0
0.0
3.1
3.4
Hippoglossina oblonga
four spot flounder
0.0
0.0
4.7
0.1
Clupea harengus
Atlantic herring
0.0
0.0
0.0
6.6
Bothidae
left eye flounders
0.0
0.0
0.3
4.9
Tautoga onitis
tautog/blackfish
0.0
0.2
2.3
0.0
Etropus microstomus
smallmouth flounder
0.0
0.0
1.9
0.8
Enchelyopus cimbrius
fourbeard rockling
0.0
2.4
0.7
0.4
Pseudopleuronectes
americanus
winter flounder
2.2
2.6
0.0
0.0
250.1.6. Harmful Algal Blooms
1. Harmful Algal Blooms (HABs) are a rapid increase and accumulation of toxic or otherwise
harmful phytoplankton in a specific area and in quantities that pose threats to ecosystems
and/or human health. Concentrations of algae in the water column can exceed thousands of
cells per milliliter, and depending upon the organism involved, can discolor the water to
create a “red tide” or “brown tide” event. Harm to the ecosystem can result from massive die-
off of phytoplankton, which during microbial-mediated decomposition depletes oxygen in
the water column leading to hypoxic (very little oxygen) or anoxic (no oxygen) conditions
which can be stressful and/or lethal to aquatic organisms. Alexandrium fundyense, a common
species of harmful algae in New England waters causes paralytic shellfish poisoning (PSP) in
humans when contaminated shellfish are consumed, and has been responsible for the closure
of shellfish beds to protect human health (Anderson et al. 2005).
2. Red tides are a frequent occurrence along the coast of Maine, and are becoming more
common in Massachusetts waters (Anderson et al. 2005); warming waters due to changing
climate have been reported as at least partially responsible for the increasing occurrence of
HABs (Bricker et al. 2008; see also Chapter 3, Global Climate Change, Section 330.1).
HABs have also been shown to be triggered by increases of nutrients from outside sources
(Smayda 2008), such as increased anthropogenic or atmospheric inputs of nitrogen (Paerl et
al. 2002). Typically, bloom events occur in summer months when water is warmest and
phytoplankton production highest. While HABs have not been documented in the Ocean
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 68 of 132
SAMP area, there are a high number of potentially harmful species present (Hargraves and
Maranda 2002), and therefore the Ocean SAMP area should not be considered immune to
such threats, particularly given changing climate and noted warming trends.
250.2. Benthic Ecosystem
1. The Ocean SAMP area is located at the boundary region of two biogeographic provinces,
also known as eco-regions—the Acadian to the north and the Virginian to the south (see
Section 200 for descriptions)—with direct, broad connection to the Atlantic Ocean. The
dynamic oceanography of the Ocean SAMP area, coupled with its geologic history and
geographic juxtaposition, shapes the nature and dynamics of the existing benthic
communities. Although there have been several surveys of the benthic fauna, and recently
some detailed studies in selected areas, most done in impacted areas such as dredge material
disposal sites, there is relatively little contemporary information on benthic communities.
Consequently, our understanding of spatial and temporal dynamics, and the implications for
ecosystem functioning, are somewhat rudimentary as well as fragmented.
2. The benthic environment is an important element of coastal marine ecosystems. The benthos
provides structure for myriad organisms, such as polychaetes and amphipods, to colonize the
substrate, add organic matter to the sediments, and provide a source of food for benthic
invertebrates and fishes. The benthos also plays an important role in nutrient cycling within
marine systems. The benthic environment is further used in the disposal of wastes, and the
Ocean SAMP benthos has functioned in this capacity as a site for the disposal of dredged
materials from Narragansett Bay. The Ocean SAMP area was also the site of an oil spill, and
though the scale of the spill was small, it was considered locally to be a significant
disturbance event.
3. Benthic communities in the Ocean SAMP area are largely dominated by various species of
benthic, tube-dwelling amphipods (LaFrance et al. 2010). The bivalve Nucula, as well as
various species of polychaetes, mysids and cumaceans, fill out benthic community species
composition. Rhode Island Sound and Block Island Sound share many species, but research
survey work by LaFrance et al. (2010) suggests that benthic habitat in Block Island Sound is
more variable than in Rhode Island Sound, and that Block Island Sound is more diverse (11
phyla and 156 genera vs. 8 phyla and 75 genera, respectively). LaFrance et al. (2010) suggest
that fundamental differences in habitat make up and utilization exists between Block Island
Sound and Rhode Island Sound, though they admit their present findings cover only a small
section of each of these large ecosystems. Further such research will provide greater
understanding of sediment type–species relationships, which at present are only tenuously
known. Having this information would greatly assist in a better understanding of the ecology
of the region, and could be a start towards the development of ground-truthed benthic habitat
maps for the Ocean SAMP area.
4. Several contemporary side-scan surveys have been made in Rhode Island Sound in relation
to dredged materials site monitoring (Battelle 2003c), and also independently by the U.S.
Geological Survey (McMullen et al. 2007; 2008). There was also a survey that was
conducted in the western portion of Block Island Sound (Poppe et al. 2006), and very recent
benthic surveys of small portions of Block Island Sound and Rhode Island Sound by
LaFrance et al. (2010). These side-scan surveys reveal high resolution details of the
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 69 of 132
sedimentary patch structure of the sea floor in Rhode Island Sound and Block Island Sound.
This benthic patch structure is quite complex and comprised of a variety of topographic
features shaped by the dynamic sedimentary environments (erosional, sorting and reworking,
and transport, see Section 210; LaFrance et al. 2010). The biologic sampling and field
ground-truthing needed to correlate side-scan imaging to benthic habitat types and probable
species assemblages has only recently begun, but will provide a very useful ecological
assessment and resource management tool as it is conducted and results are released.
5. Based on observed benthic change between surveys completed in 1991 and 1994, Driscoll
(1996) suggested that anthropogenic effects have greater impact on reworking benthic
surface sediments in Block Island Sound than large storms after finding an increase in the
distribution and density of trawl door scars caused by fishing gear dragged across the
seafloor in their survey area. Fishing can have local impacts on habitat as well as more wide-
spread impacts on species biodiversity due to re-suspension of particulates, chemical impacts
causing changes in nutrient cycling, and biological impacts from changes in species
composition (DeAlteris et al. 2000). Of interest to note is that the dominant benthic
invertebrates of the Ocean SAMP area—tube-dwelling, ampeliscid amphipods—appear to do
well in disturbed areas; it is unclear if fishing activity that disturbs the bottom is having either
a positive or negative impact, if any, on these species. LaFrance et al. (2010) found that
benthic habitat areas comprised of highly mobile sediments tended to have low diversity and
low abundances, suggesting that organisms found in these habitat types must be able to
withstand repeated disturbance events. This is an area were further study is needed to better
determine the impacts, both positive and/or negative, of disturbance events, both natural and
of anthropogenic origin, on benthic communities and the ecosystem as a whole.
6. Maps of benthic habitat can be an important element in understanding ecosystem dynamics,
but are challenging to develop. While various classification schemes have been proposed,
most existing schemes are based on physical factors such as bathymetry, sediment grain size,
sediment texture and/or topographic features. LaFrance et al. (2010) provide a summary
description of the various approaches to mapping benthic habitats, their pluses and minuses,
and limitations. Regardless of the scheme, the intent is to assist in the identification of
habitats of key importance to the ecosystem, and to guide both future research efforts as well
as management initiatives. Several proxy maps have been developed for use in considering
the ecology of Rhode Island and/or Block Island Sounds using sediment composition, and
most recently “surface roughness,” a basic measure, interpreted from sidescan sonar imaging,
of the unevenness of the seafloor bottom topography.
7. Figure 2.25 shows benthic geological environments, and genus-defined benthic geological
environments, as interpreted from side scan imagery, sub-bottom profile imagery, sediment
samples, and underwater video surveys reported by LaFrance et al. (2010). Zajac (2009)
developed a first order compilation of benthic species–sediment type relationships (Table
2.7) based on the published literature. There appears to be basic agreement in distribution of
some types, for example Byblis (bottom panel) in coarse sand and gravel areas (top panel),
while for others, Ampelisca for example, the agreement is less clear. Further mapping such as
that conducted by LaFrance et al. (2010) will help to better define the benthic environment of
the Ocean SAMP area, and may allow for comparison to past surveys that may have
accurately identified the geographic location of sample sites. The survey results of LaFrance
et al. (2010) are in general agreement with past survey findings that tube-dwelling amphipods
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 70 of 132
are the most abundant benthic organism. LaFrance et al. (2010) suggest that the large mats
created by tube-dwelling amphipods are valuable benthic habitat that provides a positive
influence on the benthic ecosystem.
Table 2.7. First approximation of species preferences, based on the published literature,
for habitats in the Ocean SAMP area (adapted from Zajac 2009).
Sediment Type
Species Association
Silt & Silty Sand
Amphipod–Ampelisca agassizi, A. Vadorum;
Bivalve–Nucula proxima
Coarse Sand/ Sand–Gravel
Amphipod– Byblis serrata, Acanthohaustorius
millsi; Polychaete–Aricidea catherinae
Mud
Amphipod– Leptocheirus pinguis
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 71 of 132
Figure 2.25. Benthic geological environments (top) and genus defined benthic
geological environments (bottom) in a select portion of Block Island Sound
(LaFrance et al. 2010). Top panel key: DB=Depositional Basin; GAF=Alluvial Fan;
GDP=Glacial Delta Plain; M=Moraine; MS=Moraine Shelf; LFDB=Lake
Floor/Depositional Basin; sisa=silty sand; bgc=boulder gravel concentrations;
cgp=cobble gravel pavement; csd=coarse sand with small dunes; pgcs=pebble gravel
coarse sand; ss=sheet sand; sw=sand waves.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 72 of 132
8. Habitat diversity promotes species diversity—the more complexity a habitat contains the
greater the number of species the habitat can generally support (Eriksson et al. 2006). A
potential proxy for habitat complexity in marine benthic ecosystems could be surface
roughness. The presumption is that the rougher the bottom, the greater the vertical
complexity, which could be equated with the promotion of increased species diversity. King
and Collie (2010) have developed a first-order interpretation of bottom roughness from
sidescan sonar images for the Ocean SAMP area (Figure 2.26). Until further interpretation
accompanied by groundtruthing occurs, increased surface roughness, as shown in Figure
2.26, should be considered only as providing the potential for habitat that promotes increased
species diversity and/or abundance. Initial findings by LaFrance et al. (2010) suggest that the
relationship between surface roughness and habitat diversity appears to vary according to the
scale at which surveys are conducted and the accompanying statistical routines used to
interpret the relationship. They find that a relationship does exist between surface roughness
and habitat diversity, though it is clear that further research needs to be conducted, at
appropriate scales, to elucidate how this relationship relates to species abundances and uses
of the various benthic habitats in the broader Ocean SAMP area. Malek et al. (2010) also
found a trend towards greater habitat complexity, but only for Block Island Sound, based on
acoustically derived surface roughness interpretation, but again suggesting that more research
is needed to further verify and build upon these findings.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 73 of 132
Figure 2.26. Benthic surface roughness as a first approximation proxy for habitat complexity in the Ocean SAMP area (King and Collie
2010).
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 74 of 132
9. The Rhode Island Sound Disposal Site (RISDS), located in Rhode Island Sound
approximately 17 km south of Point Judith (Figure 2.21), received four million cubic meters
of dredged materials removed during the Providence River and Harbor Maintenance
Dredging Project between April 2003 and January 2005. Wilson et al. (2009) found that
sediment in the disposal site often had a black coloration, but low dissolved oxygen
concentrations (e.g., hypoxic conditions) were not found. Wilson et al. (2009) also found that
species diversity in the disposal site was lower than nearby reference sites, but noted that the
benthic community was recovering relatively rapidly with Stage II (intermediate, post
disturbance community) and III (stable equilibrium community) infauna present in
abundance three to four years post-disturbance.
10. Dredged materials from the Providence River channel had been disposed of in Rhode Island
Sound previously at a site 4 miles south of Newport at the mouth of Narragansett Bay (Figure
2.21; Saila et al. 1972). Between December 1967 and September 1970, approximately 8.2
million cubic yards of dredged materials were deposited on this site. The benthic community
structure described by Saila et al. (1972) at reference sites is similar to those noted by Wilson
et al. (2009), suggesting recovery of the benthic ecosystem from the disposal disturbance
event at this site as well.
11. A spill of No. 2 fuel oil occurred in the nearshore Ocean SAMP area (Figure 2.21) during
January of 1996 and toxicity levels detrimental to benthic invertebrates were found in the
sediments immediately following the disturbance. It is unclear if toxicity threats to benthic
invertebrates continue to exist, but based on the time span since the spill it could be assumed
that it would be minimal; Ho (1999) found rapid recovery of the benthic community within
the year following the spill. It is not known if ecological impact might occur from the
disturbance of sediments in areas previously impacted by the spill.
250.2.1. Invertebrates
1. Invertebrate species make up a large proportion of the biota found in the benthic ecosystem,
and they play an important role as a food source for fishes, and for birds in shallow waters.
The invertebrate community is often quite patchy, largely because of the highly diverse
nature of the sediment types that have been transported, sorted, and deposited in specific
areas on the seafloor landscape. Sediment type is an important determinant regarding the
form of benthic community that will exist in marine aquatic ecosystems. The patchwork
nature of the benthic community similarly sets the stage for the distribution of fishes and
larger organisms.
2. The dominant benthic invertebrates of the Ocean SAMP area tend to be several species of
amphipods that inhabit a variety of habitat types in a patchy distribution. Bivalves,
polychaetes and mysids are also significant components of the benthic invertebrate fauna of
the Ocean SAMP region.
3. Theroux and Wigley (1998) conducted an expansive survey (geographically), but those data
are now more than a decade old, and at a scale too broad for specific use in the Ocean SAMP
area. Given contemporary reports of rapid ecological change as a result of changing climate,
follow-up work for comparative purposes would be an asset in understanding the ecology of
the Ocean SAMP area.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 75 of 132
4. Published accounts suggest that the macrobenthic fauna in the Ocean SAMP area is
comprised of several species groups that show varying affinities to certain bottom types
(adapted from Zajac 2009; see Table 2.7). There appears to be possible seasonality, as well as
change due to sediment transport and reworking, though separation of the two has not been
attempted:
a. Steimle (1982) found that there was an assemblage associated with silty fine sands
dominated by several species of ampeliscid amphipods (e.g., Ampelisca agassizi) and
the nut clam, Nucula proxima.
b. An assemblage found in coarser sands was dominated by several other amphipod
species (e.g., Byblis serrata, Acanthohaustorius millsi) and several polychaete species
(e.g., Aricidea catherinae). This latter assemblage was fairly distinct in February, but
by September, assemblages at the sandy and gravely stations were more variable.
c. Steimle (1982) noted that the assemblages he found were similar to those defined by
Pratt (1973) for different sediment types but did vary, likely due to complex
topography and sediment patch structure as shaped by oceanographic processes.
d. Steimle (1982) suggested that benthic communities were relatively stable over
decadal periods, as the assemblages found in 1976 were similar to those found in the
late 1940s.
e. Hale (2002) reviewed this earlier work as well as studies conducted by the U.S.
Environmental Protection Agency (EPA) as part of the Environmental Monitoring
and Assessment Program in the early 1990s and by the National Marine Fisheries
Service (NMFS) (Steimle 1990; Theroux and Wigley 1998) for the area around Block
Island. In general, the benthic communities described in these studies were similar to
those found in previous surveys, with dominant species including several amphipods,
the bivalves Nucula, Mytilus, and Arctica and several polychaete species, including
Prionospio steenstrupia, Nephtys incisa, and Clymenella torquata. The relative
dominance of these species varied with geographic location, sediment type, and
organic content (Hale 2002).
f. LaFrance et al. (2010) found that in samples from both Block Island Sound and
Rhode Island Sound that small surface burrowing polycheates of the genus
Lumbrineris where the most broadly distributed, followed by small surface burrowing
amphipds of the genus Unciola and large deep burrowing polycheates of the genus
Glycera. With regards to abundance, LaFrance et al. (2010) found the tube-swelling
amphipod genus Ampelisca to be the most abundant, followed by Leptocheirus, also a
tube-dwelling amphipod.
5. The American lobster (Homarus americanus) is a large, scavenging, benthic invertebrate
living in the Ocean SAMP area, and is of great commercial importance in the region. See
Chapter 5, Commercial and Recreational Fisheries, for detailed life history or the American
lobster.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 76 of 132
250.2.1.1. Block Island Sound
1. Savard (1966) noted a gravel/sandy-gravel cover on the ridge (moraine) running between
Montauk Point and Block Island, the ridge and shallow area to the north of Block Island, and
in the deep channels of western Block Island Sound. Silty-sand was found to cover most of
the east-central plain of Block Island Sound and the protected shallows east of Gardners
Island. Sand was found to cover most of the western and central areas of the sound, and the
floor of the channel that cuts through the Montauk–Block Island ridge. Patches of gravelly-
sand or silty-sand were found scattered throughout the sandy-bottomed area. Savard also
found that mean sediment size decreased with distance from shore toward the center of Block
Island Sound, with coarsest sediments found along the Montauk–Block Island ridge and
parallel to the Rhode Island shore in the northern portion of Block Island Sound. Well-sorted
sediment was found in southwestern Block Island Sound near Cerberus Shoal, moderately-
sorted sediment was found north of the Montauk–Block Island ridge and in western Block
Island Sound. Savard did not collect biological data and so species mapping to sediment type
cannot be done until sediment–species relationships are better defined.
2. Steimle (1982) found the amphipods Ampelisca agassizi and A. vadorum, and a bivalve,
Nucula proxima, to dominate silt and silty-sand sediments. Steimle (1982) noted that, based
on previous reports of benthic fauna of Block Island Sound, that Ampelisca has dominated
the benthic fauna for at least half a century, suggesting that the benthic community had been
somewhat stable over that time frame. Work from Byron and Link (in press) on diet
composition of fish species suggest that benthic communities have been stable across the
entire Northeast Atlantic Shelf ecosystem, which includes the Ocean SAMP area, for the past
30 years despite widespread disturbance to the benthic habitat by both natural and
anthropogenic forces.
3. Smith (1950) found the amphipod Leptocheirus pinguis to be very well adapted to muddy
bottom areas in Block Island Sound. He found the tubes to be quite easily constructed and
not very permanent—individual amphipods were seen to leave a burrow and build a new one
when needed rather than travel back to an existing tube, suggesting the species to be quite
mobile and adaptable. Smith (1950) suggests that fish trawl disturbance on the bottom does
not harm this species of amphipod, and in fact suggests that such disturbance enhances
conditions by putting detritus into the water column where it can be accessed as food; loss of
dwelling tube was not problematic for this species.
4. Deevey (1952a) conducted limited sampling of benthic organisms during surveys. She found
ampeliscid amphipods to be very abundant in bottom samples, more so than any other types
except for the caprellid amphipod Aeginella longincornis. The mysid, Neomysis americana,
was found to be very abundant in Block Island Sound during late summer, as were various
species of cumacean. The decapods Crangon septemspinosus and Dichelopandalus
leptocerus were abundant during fall months. All of these species are important prey items
for many fish species residing and migrating through the Ocean SAMP area.
5. Sediments composed of coarse sand and/or gravel had distinct fauna of mixed amphipods
and polychaetes, which often varied seasonally (Steimle 1982). Steimle considered this
finding as showing the patchiness of the benthic habitats in Block Island Sound and that it
was a reflection of the complex topography. Steimle’s Table 1 (Steimle 1982) provides a full
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 77 of 132
listing of benthic invertebrates sampled during the survey conducted; Steimle also noted that
the species assemblage found resembled those reported from the inner continental shelf
and/or other sounds in New England, and as reported by Pratt (1973).
250.2.1.2. Rhode Island Sound
1. Wilson et al. (2009) found reference sites in Rhode Island Sound to be typical of shallow-
water New England benthic habitats, and that they were dominated by the bivalve Nucula
annulata; the amphipods Crassicorophium crassicorne, Ericthonius fasciatus, Ampelisca
agassizi, Unciola irrorata, and Lepthocheirus pinguis; and sabellid polychaetes; there is
considerable similarity in species with those reported for Block Island Sound.
2. Benthic infaunal studies were conducted in Rhode Island Sound as part of the U.S. Army
Corps of Engineers’ Long-term Dredged Material Disposal Site Evaluation Project at four
sites in 2001, and at two sites in 2003 (Battelle 2002a, 2003a; adapted from Zajac 2009):
a. In 2001 all four sites were numerically dominated by the amphipod, Ampelisca
agassizi, and the clam, Nucula annulata—comprising approximately 54 percent of
the total infaunal abundance—and had relatively high abundances of the annelid
worms, Polygordius sp., Tharyx acutus, Oligochaeta spp., Ninoe nigripes, Levinsenia
gracilis, and Exogone hebes; the crustaceans Byblis serrata (Amphipoda) and
Eudorella pusilla (Cumacea); and the clam Nucula delphinodonta (Battelle 2002a).
b. Classification analyses indicated that almost all sampling stations at all four sites
showed a 60 percent similarity. The exception was two sampling stations at one of the
sites just south of Narragansett Bay, both of which had relatively high silt content and
these were only roughly 25 percent similar to the other sites. There were no other
distinct clusters of sites, but there was some clustering of stations within sites,
suggesting that benthic infaunal communities in Rhode Island Sound may not vary
greatly over scales of tens of kilometers. Any variations that may occur may be due to
small-scale differences in sea floor structure or other processes (Zajac 2009).
c. An additional survey was conducted in 2003 at one site overlapping with one of the
2001 survey sites. The infaunal communities found were generally similar to those
found in 2001 (Battelle 2003a), although there were some differences that might be
attributed to seasonal variation. In addition to benthic grab samples, candidate
disposal sites were surveyed using sediment profiling imagery. The data collected
were analyzed using a disturbance/succession model developed by Rhoads et al.
(1978) and Rhoads and Germano (1986). Using this model, the analyses suggest that
the successional stages of the communities vary considerably over relatively small
spatial scales (Battelle 2002b; 2003b), suggesting frequent disturbance events.
3. The ocean quahog (Arctica islandica) and sea scallop (Placopecten magellanicus) are large
bivalves found in the Ocean SAMP area (see Chapter 5, Commercial and Recreational
Fisheries, for distribution and life history characteristics). Both species are found broadly
throughout the area, often at high densities. As filter feeding bivalves, these organisms are
capable of filtering large volumes of water and reducing particulate matter and plankton
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 78 of 132
concentrations; the impact of feeding habits on the Ocean SAMP area ecology, however, are
not known.
250.3. Fishes
1. There is a diverse and dynamic fish community in Ocean SAMP area waters, as recent work
by Malek et al. (2010) suggests: Rhode Island Sound was found to have greater fish
abundance and higher fish biomass than Block Island Sound, which corroborates a similar
finding by Nixon et al. (2010) who suggest this to be so because Rhode Island Sound appears
to have higher primary productivity than does Block Island Sound. Malek et al. (2010) also
find that Block Island Sound has greater fish community diversity than does Rhode Island
Sound. Malek et al. (2010) further found that a community of larger, more evenly distributed
fish are found at depth, while shallow waters contain more diverse communities of smaller
fish. Finally, Malek et al. (2010) found a strong relationship between benthic habitat
complexity and demersal fish community diversity, with complex habitats containing greater
fish diversity. In considering fish community ecology in the Ocean SAMP area, it must be
recognized that this community has been manipulated, and perhaps ecologically altered, by
commercial and recreational fisheries practices that have taken place historically. It is
therefore not fully possible to determine what fish community make up may have been in the
past relative to what we see at present.
2. The structure of the fish community in the Ocean SAMP area has undergone recent major
change from a community dominated by demersal (near bottom) species to one dominated by
pelagic (water column) species (Collie et al. 2008). A corresponding trend towards fish
species with a preference for warmer water temperatures suggests that broad-scale warming
trends may be a significant driving force of this fundamental ecosystem level change. These
shifts are noted not only for commercially harvested species, but for species of non-
commercial value as well. More research is needed to understand how other ecosystem
variables outside of water temperature are being altered over time, and how the Ocean SAMP
ecosystem at large is responding (see also Chapter 3, Global Climate Change, Section 330.1).
3. Fish play an important role in food web dynamics as higher-order predators within the
ecosystem. Fish utilize the abundant stocks of producers—phytoplankton—and lower-order
consumers such as zooplankton, converting their organic matter into larger “packages” of
high-quality protein that then become available as food to birds, marine mammals, and large
fishes and apex predators such as tuna and sharks. Fish are an important food and an
important element of the economy of the state of Rhode Island with regard to both
commercial and recreational fisheries. This chapter considers fish from the perspective of
their role in the ocean ecosystem; for information on fisheries and the life histories of
important commercial and recreational species, see Chapter 5, Commercial and Recreational
Fisheries.
4. Circulation and salinity play a role in fish species distribution and abundance. For instance,
Merriman and Sclar (1952) noted a correlation between salinity in Block Island Sound and
years of heavy spawning for at least certain species of fish. In one year of their survey the
salinity in Block Island Sound was 2‰ higher than in other years, which corresponded to
being a year during which a heavy spawn was noted. Similar heavy spawning was not seen in
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 79 of 132
other years when salinities tended to be lower. Merriman and Sclar (1952) found that
precipitation and runoff were both lower during the year of high salinity/heavy spawning.
Three years later they noted an increase in the catch of weakfish (a species with high
reproductive success during the high salinity event), again suggesting correlation between
these events. Merriman and Sclar (1952) noted however, that there were not enough data to
make correlations with a large degree of certainty, though they did suggest causality.
Bohaboy et al. (2010) find that season is a strong determinant of both fish diversity and fish
abundance in the Ocean SAMP area, with fall having greater numbers of fish present than
during spring.
5. Food is a major determining factor in maintenance of healthy populations, and the
importance of the benthic ecosystem as a food source to fish populations in the Ocean SAMP
area is not trivial. Smith (1950) found that bottom invertebrates made up 81% of the total
food of bottom fishes in Block Island Sound. Squid made up another 7.1% of the total, and
fish comprised the remaining 11.9%. In fact, Smith (1950) found that only 25% of the bottom
invertebrates sampled were not important as sources of food for fishes in Block Island
Sound. Of the bottom invertebrates eaten by bottom-dwelling fishes, 90.2% were
crustaceans, 3.5% were annelids, and the remainder a mix of hydrozoans, gastropods,
echinoderms and other organisms. The amphipods Leptocheirus pinguis and Unciola
irrorata, the crab Cancer irroratus, and the shrimps Crangon septemspinosa and Upogebia
affinis, made up 78% of the biomass eaten by the bottom fishes sampled.
6. Amphipods are very abundant benthic invertebrates, and are important members of the
Ocean SAMP benthic community, providing an abundant, accessible food source to the fish
community. Smith (1950) found that crustaceans in general made up about 90% of the
bottom invertebrates eaten by fish, with amphipods making up 60%. One amphipod
species—Leptocheirus pinguis—made up 46% of the bottom invertebrates eaten by fish in
Block Island Sound.
7. Despite their abundance, Smith (1950) found some very selective, preferential feeding on
amphipods by several species of fish. For instance, sculpin preferred to prey upon male
Leptocheirus pinguis amphipods, while skates showed no preference. Smith (1950) provides
an in-depth evaluation of amphipod–fish predator–prey relationships and how they affect
population ecology of the amphipod species.
8. While amphipods may provide the primary source of food to bottom-feeding fishes, other
species are also taken as food and are important contributors to the Ocean SAMP area food
web. The rock crab (Cancer irroratus) was the second most important food source for
bottom fishes, but only immature forms (to 5 cm carapace width) were eaten (Smith 1950).
The mysid Neomysis americana was found to be both abundant and important as a fish food
item, particularly for sea robins (Richards et al. 1979). The hydroid Obelia articulata was
found by Smith to be an important springtime source of food for flounder.
9. In a fisheries survey in Block Island Sound conducted by Smith (1950), the following benthic
fishes were found to be the most abundant: common skate (Raja erinacea), big skate (Raja
diaphanes), winter flounder (Pseudopleuronectes americanus), windowpane flounder
(Lopnopsetta aquosa), whiting (Merluccius bilinearis), longhorn sculpin (Myoxocephalus
octodecimspinosus), eel pout (Macrozoarus americanus) and the common sea robin
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 80 of 132
(Prinotus carolinus). Chapter 5, Commercial and Recreational Fisheries, provides a brief
overview of seasonality and biomass estimates for a variety of commercially
important/valuable species found in the Ocean SAMP area, as well as individual life history
descriptions. Chapter 5, Section 520 also provides a table that gives a first order
identification of the various habitat requirements of commercially important/valuable species
in the Ocean SAMP area. These data are not site specific; until benthic sediment/habitat
mapping is completed for the Ocean SAMP area benthic habitat affinities for fishes cannot be
addressed with surety.
10. Brown (2009), based on Northeast Fisheries Science Center trawl survey results (fall
sampled since 1963, spring since 1968, winter and summer since 1992), found 119 species of
fishes and 9 species of crabs; 55 species occurred in less than 1% of the tows. Table 2.8
shows the percentage of tows containing various species, while Table 2.9 shows the biomass
of various species taken in the same tows. Some species, winter flounder for instance, appear
to be broadly distributed (e.g., found in 89% of the tows) but only in very small numbers
(e.g., 3.2% of the total biomass). Others, spiny dogfish for instance, appear to be very
numerous, but found in dense concentrations rather than scattered about.
Table 2.8. Percent occurrence of species landed in trawls taken in Block Island Sound
(from Brown 2009).
Species
Percent of Tows
Winter flounder
89.0
Little skate
83.8
American lobster
77.1
Windowpane flounder
72.2
Silver hake
65.0
Winter skate
53.1
Longhorn sculpin
52.8
Table 2.9. Percent biomass of species landed in trawls taken in Block Island Sound (from
Brown 2009).
Species
Percent Biomass
Spiny dogfish
41.0
Little skate
14.3
Winter skate
8.4
Ocean pout
5.0
Scup
3.9
Winter flounder
3.2
Loligo squid
2.3
11. Sanders (1952) noted an interesting use of the Ocean SAMP area as a winter refuge for
Atlantic herring (Clupea harengus). In a survey of Block Island Sound, the species was
present from January to mid-March, but in two distinct groups: spent adults (e.g., post-
spawning) and immature adolescents. The spent adults were dominant through early
February, at which point immature adolescent fishes dominated. Of interest is that Sanders
(1952) notes that the herring restricted their distribution to a narrow band of the coldest water
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 81 of 132
just south of Block Island, between 2 and 4°C, dispersing widely once waters warmed; the
fish did not feed often while in the coldest water, but did switch to a totally planktonic diet
once dispersed from the cold water refuge. Sanders (1952) suggests the fish use this as an
adaptive strategy to slow metabolism over the winter months to conserve energy. Once the
herring began feeding again, a large copepod, Pseudocalanus minutus, made up 70% or more
of the food items ingested, and was noted to be the food of preference for the Atlantic herring
in Block Island Sound waters.
12. Brown (2009) characterizes the major demersal (e.g., living near but not necessarily on the
bottom) and pelagic fish and invertebrates as residents or migrants of the Ocean SAMP area
(Figure 2.27). The majority of the pelagic species are seasonal users of the area, with most of
those arriving during spring and leaving during the fall. Relatively few major species are
resident in the Ocean SAMP area. This suggests that the overall fish community of the Ocean
SAMP area largely follows a seasonal cycle of abundance. These findings are corroborated
by recent research by Bohaboy et al. (2010) in the Ocean SAMP area. Water temperature and
food availability are no doubt major elements in shaping fish abundance patterns, both of
which also exhibit strong seasonality. In general terms, early spring sees the start of a major
influx of migratory species to the area, reaching a maxima in later summer then declining
throughout the fall season. This pattern is similar to those noted for zooplankton and
ichthyoplankton communities.
Figure 2.27. Seasonal composition of major fish and invertebrate species in the Ocean
SAMP area (from Brown 2009).
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 82 of 132
13. While surveys have shown the seasonal nature of the migrations of fishes into and out of the
Ocean SAMP area, Collie et al. (2008) have found a more fundamental shift in species
abundances that have significant implications at ecosystem scales. Collie et al. (2008) have
found a progressive shift in the species composition of the fish community at a sampling
station located in Rhode Island Sound at the mouth of Narragansett Bay. Demersal fishes
dominated in the 1960s, but during the 1970s benthic invertebrates (e.g., lobster, crabs)
increased dramatically in abundance (Figure 2.28). During the 1980s, a major rise in the
abundance of pelagic fishes and squid was noted, and by 1994, 50% of the species sampled
were pelagic species. Though some demersal fish species have recently increased in
abundance, the fish community remains dominated by pelagic species in the sampling area
and there is no indication that species composition is moving towards that seen in the 1960s
(e.g., dominated by demersal fishes). This is a fundamental shift in ecosystem composition,
and effects upon the larger ecosystem are not known. Figure 2.29 shows increase and
decrease of various species at the mouth of Narragansett Bay, again reinforcing the species
shift from demersal to pelagic species. Figure 2.30 shows change over time for several
species; squid and the little skate have undergone particularly dramatic increases in
population size in recent times.
1959 1963 1967 1971 1975 1979 1983 1987 1991 1995 1999 2003
Year
0
200
400
600
800
Annual mean catch per 30-min tow
Squid
Pelagic fish
Benthic invertebrates
Demersal fish
Figure 2.28. Trawl catches at Whale Rock at the mouth of Narragansett Bay/Rhode
Island Sound (from Collie 2009), showing the increase in pelagic fish and squid since
1980.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 83 of 132
-0.2
-0.1
0.0
0.1
0.2
o
oooo o oooo
ooooooooooo ooo o
Cunner
Red hake
Longhorn sculpin
Sea star
Silver hake
Northern searobin
Winter flounder
Windowpane
Horseshoe crab
Tautog
American lobster
Atlantic herring
River herring
Scup
Spider crab
Summer flounder
Cancer crab
Fourspot flounder
Lady crab
Weakfish
Little skate
Bluefish
Striped searobin
Longfin squid
Butterfish
Instantaneous rate of change
Figure 2.29. Rate of increase/decrease of species collected at Whale Rock at the mouth
of Narragansett Bay/Rhode Island Sound (from Collie 2009). Left of 0.0 is decreasing in
abundance, to the right increasing.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 84 of 132
1960
1970
1980
1990
2000
0
100
200
300
Winter flounder
1960
1970
1980
1990
2000
0
100
200
300
400
Butterfish
1960
1970
1980
1990
2000
0
100
200
300
Silver hake
Bay Station
Sound Station
1960
1970
1980
1990
2000
0
100
200
300
400
Scup
1960
1970
1980
1990
2000
0
100
200
300
400
500
Cancer crab
1960
1970
1980
1990
2000
0
20
40
60
80
100
120
Red hake
1960
1970
1980
1990
2000
0
10
20
30
40
50
60
American lobster
1960
1970
1980
1990
2000
0
50
100
150
200
250
300
Longfin squid
1960
1970
1980
1990
2000
0
20
40
60
Little skate
Year
Annual mean catch per 30-min tow
Figure 2.30. Annual mean abundance of nine species collected at Whale Rock at the
mouth of Narragansett Bay/Rhode Island Sound (from Collie 2009).
14. Collie et al. (2008) also found a decrease in body size of the fish species represented, and that
species composition tended towards ones with preference for warmer water temperatures
(Figure 2.31). This may be indicative of regional shifts in fish species as a result of changing
climate, particularly warmer water temperatures (Nye et al. 2009). Collie et al. (2008) noted
that they expect a continuation of the shift to warm water pelagic species, perhaps over time
developing a fish community more similar to that of Delaware Bay or Chesapeake Bay. Perry
et al. (2005) have documented similar shifts in both commercially and non-commercially
valuable fish species, with an average latitudinal shift in distance of 175 km (108 mi; range
from 48 km (30 mi) to 403 km (250 mi)). Some species, cod for instance, may move further
northward while southern species and migrants might become more abundant; winter
flounder in particular will be more vulnerable and may undergo reduction in its distribution
and availability in the area (Rose 2005).
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 85 of 132
Figure 2.31. Community metrics for long term trawl samples collected at Whale Rock at
the mouth of Narragansett Bay/Rhode Island Sound. Note the distinct decrease in fish
length and the increase in preference for warmer water temperatures (from Collie 2009).
15. Similar change in fish community composition is being noted at various scales and
geographic locations. Nye et al. (2009) took an in-depth look at the potential impacts of
changing climate on fisheries in the Northeast Atlantic, and found that 24 of the 36 stocks
assessed had a statistically significant response to warming water temperatures. The waters
over the Continental Shelf have undergone a 10-year span of consistent warming, with the
largest change being noted in bottom waters. Based on findings from analysis of a
continuous, 40-year trawl survey (1968–2007), Nye et al. (2009) suggest several basic
responses to climate change: a shift in distribution of the species to the north (e.g., range
expansion for warm-water species; range contraction for cold-water species) or a vertical
shift in species distribution to deeper water (e.g., cold-water species). Cold-water species that
are at the southern extent of their range, for example cod, will be most impacted and may
decline in abundance (Frank et al. 1990; Drinkwater 2005; Nye et al. 2009). Alewife,
American shad, silver hake, red hake and yellowtail flounder all have exhibited range
contraction. Cusk, a species that uses Block Island Sound as an important nursery area
(Fahay 1992), is a species noted to be at particular risk as it is at the southern edge of its
range in the Ocean SAMP region (Nye et al. 2009). Nye et al. (2009) also found the
relationship to hold for species with little or no commercial value (e.g., sea ravens, longhorn
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 86 of 132
sculpin). These overall trends are of significant importance in the Ocean SAMP area as it is
at the geographic boundary of two distinct eco-zones and change may be dramatic. While
these changes are already noted, other change, such as increased early life mortality due to
increased temperatures, or changed circulation patterns as a result of warming that transport
eggs and/or larvae to unfavorable habitat, could significantly impact fish populations in the
Ocean SAMP area. This is an area that is open for new research efforts.
250.4. Marine Mammals
1. Marine mammals—whales, dolphins, seals—are large predators within the Ocean SAMP
ecosystem. Toothed whales, dolphins and seals are typically fish and squid eaters, entering
the Ocean SAMP area on either an occasional or seasonal basis. Baleen whales also feed on
schooling fishes, though some baleen whales, the right whale for instance, feeds exclusively
on patches of zooplankton. Changes in distribution and/or abundance of marine mammal
prey items—squid, fish, zooplankton—as a result of changing climate, may influence the
distribution and abundance of marine mammals in Ocean SAMP waters. See Chapter 3,
Global Climate Change, Section 330.1 for further details.
2. Available data results from sightings, strandings, and/or fishery bycatch data (Kenney and
Vigness-Raposa 2009). There are 50 species of marine mammals known from the North
Atlantic Ocean (Kenney and Vigness-Raposa 2009), and all are protected under the U.S.
Marine Mammal Protection Act. In addition, some marine mammals are classified as
endangered or threatened, and therefore protected under the U.S. Endangered Species Act.
Single manatees have been sighted in Rhode Island waters, but can be considered as
stragglers from southern waters.
250.4.1. Cetaceans
1. Cetaceans include whales, dolphins, and porpoises; they largely use only the water column
component of the Ocean SAMP area, following and feeding upon various prey items. Due to
their large size, they are capable of consuming large quantities of fish and plankton. Kenney
and Vigness-Raposa (2009) report thirty (30) cetaceans in the Ocean SAMP area: ten (10) that
can be considered common to abundant, four (4) considered as regularly noted, and sixteen
(16) as rare (Table 2.10).
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 87 of 132
Table 2.10. The occurrence of marine mammals and sea turtles in Continental Shelf
waters, which includes, but is not restricted to, waters in the Ocean SAMP area. (Kenney
and Vigness-Raposa 2009).
Species
Occurrence
North Atlantic right whale
Common
Humpback whale
Common
Blue whale
Rare
Fin whale
Common
Sei whale
Regular
Bryde’s whale
Rare
Minke whale
Common
Sperm whale
Common
Pygmy sperm whale
Regular
Dwarf sperm whale
Rare
Northern bottlenose whale
Rare
Cuvier’s beaked whale
Rare
Blainville’s beaked whale
Rare
Gervais’ beaked whale
Rare
Sowerby’s beaked whale
Rare
True’s beaked whale
Rare
Beluga whale
Rare
Harbor porpoise
Common
Long-finned pilot whale
Common
Short-finned pilot whale
Rare
Killer whale
Rare
False killer whale
Rare
Risso’s dolphin
Common
Atlantic white-sided dolphin
Common
White-beaked dolphin
Regular
Common bottlenose dolphin
Common
Short-beaked common dolphin
Common
Striped dolphin
Regular
Atlantic spotted dolphin
Rare
Pan-tropical spotted dolphin
Rare
Harbor seal
Common
Gray seal
Common
Harp seal
Common
Hooded seal
Regular
Ringed seal
Rare
West Indian manatee
Rare
Leatherback sea turtle
Common
Loggerhead sea turtle
Common
Kemp’s ridley sea turtle
Regular
Green sea turtle
Rare
2. For baleen whales, Kenney and Vigness-Raposa (2009) report that fin, humpback and minke
whales occur year round throughout continental shelf waters, but all are relatively rare in the
Ocean SAMP area. Figure 2.32 shows relative abundances of various species of baleen whales
in the Ocean SAMP area. Right whales, a particularly endangered species with approximately
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 88 of 132
400 individuals remaining, can be common offshore during spring and fall migration, but are
not common in the Ocean SAMP area. However, in one event in April 2010, nearly 100 right
whales were spotted feeding in Rhode Island sound, indicating that they do sometimes appear
within the Ocean SAMP boundary area (Northeast Fisheries Science Center 2010). Waters
outside of the Ocean SAMP area see greater abundances of marine mammals, with the fin
whale being the most common, and with some visitation into the Ocean SAMP area during
summer months with sightings primarily in deeper waters. Baleen whales appear to utilize the
area to the east of Nantucket Sound/Vineyard Sound more heavily than they do the Ocean
SAMP area (Figure 2.32).
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 89 of 132
Figure 2.32(a). Modeled seasonal relative abundance patterns of right whales in the Ocean SAMP area, corrected for uneven survey
effort (from Kenney and Vigness-Raposa 2009). Darker areas on the map represent areas of higher abundance; the darker the color the
greater the relative abundance.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 90 of 132
Figure 2.32(b). Modeled seasonal relative abundance patterns of humpback whales in the Ocean SAMP area, corrected for uneven
survey effort (from Kenney and Vigness-Raposa 2009). Darker areas on the map represent areas of higher abundance; the darker the
color the greater the relative abundance.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 91 of 132
2.32(c). Modeled seasonal relative abundance patterns of fin whales in the Ocean SAMP area, corrected for uneven survey effort (from
Kenney and Vigness-Raposa 2009). Darker areas on the map represent areas of higher abundance; the darker the color the greater the
relative abundance.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 92 of 132
3. For toothed whales, the harbor porpoise is the most common, along with the common dolphin
and the Atlantic white-side dolphin; pilot whales are also found on occasion in Ocean SAMP
area waters, but are more generally found farther offshore. Figure 2.33 shows relative
abundances of various species of toothed whales in the Ocean SAMP area. Toothed whales
appear to utilize the area to the east around Nantucket Sound/Vineyard Sound, and offshore
waters over the Continental Shelf, more heavily than they do the Ocean SAMP area (Figure
2.33).
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 93 of 132
Figure 2.33(a). Modeled seasonal relative abundance patterns of harbor porpoise in the Ocean SAMP area, corrected for uneven survey
effort (from Kenney and Vigness-Raposa 2009). Darker areas on the map represent areas of higher abundance; the darker the color the
greater the relative abundance.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 94 of 132
Figure 2.33(b). Modeled seasonal relative abundance patterns of common dolphin in the Ocean SAMP area, corrected for uneven survey
effort (from Kenney and Vigness-Raposa 2009). Darker areas on the map represent areas of higher abundance; the darker the color the
greater the relative abundance.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 95 of 132
Figure 2.33(c). Modeled seasonal relative abundance patterns of Atlantic white-sided dolphin in the Ocean SAMP area, corrected for
uneven survey effort (from Kenney and Vigness-Raposa 2009). Darker areas on the map represent areas of higher abundance; the darker
the color the greater the relative abundance.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 96 of 132
250.4.2. Pinnipeds
1. Pinnipeds are seasonal users of the Ocean SAMP area, and unlike cetaceans, pinnipeds also
utilize the terrestrial environment, largely as “haul-out” sites used for resting. While fish are
the predominant prey item of pinnipeds in this area, they have a very broad diet that includes
many invertebrate species. Kenney and Vigness-Raposa (2009) report five (5) seals in the
Ocean SAMP area: three (3) can be considered common, one (1) as regular, and one (1) as rare
(Table 2.10). Of these species, only the gray seal and harbor seal are common, with the later
being most common in the Ocean SAMP area, particularly along Block Island.
2. Harbor seals are seasonally abundant in the region from fall through spring—generally late
September to early May—with numerous known haul-out sites around Narragansett Bay and
on Block Island (Figure 2.34), which is the major haul-out area within Ocean SAMP
boundaries. There are 6 major haul out sites on Block Island, two which are heavily used
(mean # seals using the site is 8, with a maximum greater than 30) and the remaining four less
so (mean # seals using the site is 1, with a maximum greater than 5), with none being located
on the southern side of the island (Schroeder 2000). Harbor seals are rarely seen more than 20
km from shore, and mainly frequent bays, estuaries and inlets (Schroeder 2000). No specific
food studies have been conducted on harbor seals in Rhode Island, but Payne and Selzer (1989)
found sand lance to be an important food on Cape Cod. Williams (1999) found hake to be
important in the Gulf of Maine, as did Wood (2000) along the mid-coast region of Maine.
Olesiuk et al. (1990) found harbor seals to be opportunistic feeders, taking advantage of
whatever food items are readily and easily available, though Payne and Selzer (1989) noted a
preference for small schooling fishes when available, but that they will shift prey species
rapidly in response to prey availability.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 97 of 132
Figure 2.34. Harbor seal haul-out sites. Yellow star area on Block Island is a major seal
haul out area.
3. Gray seals (Halichoerus grypus) are a more northerly species that ranges into southern New
England waters on a seasonal basis. Ridoux et al. (2007), who studied the diet of gray seals in
European waters, found them to maintain a diet of mainly fish and cephalopods, with fish
making up 96% of the diet by number and 98.6% by mass. In Canadian offshore waters,
Bowen and Harrison (1994) found that gray seals had a feeding range of about 80 km, and that
foods eaten mimicked the prey items available. They found that by weight, sand lance made up
nearly 81% of the diet, cod 11%, silver hake about 3% and flatfish and other gadoid fishes the
remainder. A similar study by Bowen et al. (1993) found that herring, cod, sand lance, silver
hake and squid made up 88%, by weight, of gray seal diet on the Scotian Shelf of Canada.
Bowen and Harrison (1994) noted differences in gray seal diets near shore and offshore, but
this could be attributed to prey availability.
250.5. Sea Turtles
1. Sea turtles are reptiles that have taken up an oceanic existence. Terrestrial resources in the
Ocean SAMP area are not utilized, and sea turtles are not known to breed or nest in these
waters. Available data results from sightings, strandings, and/or fishery bycatch data (Kenney
and Vigness-Raposa 2009). There are six species of sea turtles known from the North
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 98 of 132
Atlantic Ocean (Kenney and Vigness-Raposa 2009). All six sea turtles are classified as
endangered or threatened, and therefore protected under the U.S. Endangered Species Act.
2. Kenney and Vigness-Raposa (2009) report four (4) species of sea turtles in the Ocean SAMP
area: two (2) can be considered common, one (1) as regular, and one (1) as rare (Table 2.10).
3. Kenney and Vigness-Raposa (2009) report details for leatherback sea turtles, noting that
sightings generally occurred in continental shelf waters, not in the Ocean SAMP area. Those
leatherback turtles that do visit the Ocean SAMP area feed upon jellyfishes and other
gelatinous prey items. The few turtles that are found offshore of the Ocean SAMP area are
sighted mostly in the summer and early fall. Figure 2.35 shows the seasonal relative abundance
of leatherback turtles in the Ocean SAMP area, showing the probability for visitation in the
area is highest during summer and fall months. Chapter 3, Global Climate Change, Section
330.1 provides information on possible impacts of changing climate on sea turtles in the Ocean
SAMP area.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 99 of 132
Figure 2.35. Modeled seasonal relative abundance patterns of leatherback sea turtles in
the Ocean SAMP area, corrected for uneven survey effort (from Kenney and Vigness-
Raposa 2009).
250.6. Avifauna
1. Birds are an element of the Ocean SAMP area ecology; they are attracted to the area because
of temperate climate—many of these birds nest in the Arctic or Antarctic—and for feeding
purposes, utilizing the seasonal abundance of fish and invertebrates as an important resource.
The impact of avifauna on the overall ecology of the Ocean SAMP area is not well studied
and so how bird use shapes benthic invertebrate ecology in shallow waters is not well known
and is an area of further possible research.
2. Bird life throughout the Ocean SAMP area is dynamic, with substantial changes between
seasons and years. During summer in some years (e.g., 2009), tens of thousands of pelagic
seabirds migrate into the area for several months to feed, while in other years (e.g., 2010)
seabirds inhabit more offshore area and are not observed in the Ocean SAMP area. In
general, avifauna in the Ocean SAMP area is most abundant during fall and spring migration
periods, and during winter. Water depth is an important factor in the spatial distribution of
these birds. Gannets and loons for instance, which feed mainly on fish, frequent waters up 45
m in depth, while seaducks primarily forage in Ocean SAMP waters less than 20 m deep.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 100 of 132
3. Reinert et al. (2002) found 109 species of songbirds on Block Island during the time of
spring migration and 113 species during the fall migration, with 103 of the species found
during both seasons. Table 2.11 shows the most common passerine birds utilizing the
terrestrial portion of the Ocean SAMP area (e.g., Block Island), and season(s) they are
typically found on the island. While many species utilize Block Island as a migratory
stopover, Reinert et al. (2002) found that 38% of the spring-captured species, and 21% of the
fall-captured species, were species that are known to breed on Block Island. Reinert et al.
(2002) provide greater detail on specific island habitat use by passerine birds. Actual use of
marine waters are expected to be minimal, though tree swallows appear to utilize nearshore
air space over water on a regular basis (Paton et al. 2010), perhaps for feeding purposes.
Table 2.11. Common songbirds utilizing Block Island, and the season(s) in which they
are found on the island, and the percent of total captures for each species (Reinert et al.
2002).
Species
Scientific Name
% of Total Capture
(Spring/Fall)
Gray Catbird
Dumetella carolinensis
17.1 / 13.2
Common Yellowthroat
Geothlypis trichas
13.7 / 0
Yellow-Rumped Warbler
Dendroica coronate
10.7 / 35.1
White-Throated Sparrow
Zonotrichia albicollis
6.6 / 0
Golden-Crowned Kinglet
Regulus satrapa
0 / 4.5
Red-Eyed Vireo
Vireo olivaceous
0 / 4.1
4. Paton et al. (2010) have found approximately 25 waterbird species that commonly inhabit
and/or use the waters of the Ocean SAMP area (Table 2.12). Use of the Ocean SAMP area by
any given species of waterbird, except for various gulls, is seasonal. Figure 2.36 shows
waterbird seasonality in a graphical fashion. Waterbirds either overwinter in the Ocean
SAMP area (e.g., common eider) or use it as summer feeding grounds, perhaps after the
nesting cycle is completed (e.g., loons, scoters).
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 101 of 132
Table 2.12. Avifauna of the Ocean SAMP area as described by Paton et al. (2010).
5. Paton et al. (2010) have found that water depth is an important factor in the spatial
distribution of birds in the Ocean SAMP area. Based on a review of the literature, most sea
ducks typically forage in water of 5 to 20 m depth (Figure 2.37) where bivalves and other
forage is available. Sea ducks will therefore be largely found in nearshore habitats where
water depth allows efficient feeding. Gannets and loons are piscivorous specialists and tend
to occur in areas where water depths 30–45 m deep, and <35 m deep, respectively (Paton et
al., 2010). Razorbills were consistently found in shallower waters closer to the mainland,
common murre primarily in the central regions of the Ocean SAMP area, and dovekies
offshore over deeper depths out to the Continental Shelf (Paton et al., 2010). While
bathymetry is known for the Ocean SAMP area, benthic community composition is not and
therefore preferred/critical waterbird forage areas cannot be readily identified. For further
information on the potential effects of offshore development on bird foraging habitat, see
Chapter 8, Renewable Energy and Other Offshore Development.
Common Name
Scientific Name
Seasonal
Use
Cormorant, Double-crested
Phalacrocorax auritus
Mar–Nov
Eider, Common
Somateria mollissima dresseri
Oct–Apr
Gannet, Northern
Morus bassanus
Sep–Jun
Gull, Bonaparte’s
Chroicocephalus philadelphia
Gull, Great Black-backed
Larus marinus
All Year
Gull, Herring
Larus argentatus
All Year
Gull, Laughing
Leucophaeus atricilla
May–Nov
Gull, Ring-billed
Larus delawarensis
All Year
Loon, Common
Gavia immer
Oct–Jun
Loon, Red-throated
Gavia stellata
Oct–May
Scoter, Black
Melanitta nigra americana
Sep–may
Scoter, Surf
Melanitta perspicillata
Sep–may
Scoter, White-winged
Melanitta deglandi
Sep–May
Shearwater, Cory’s
Calonectris diomedea
Jun–Aug
Shearwater, Greater
Puffinus gravis
Jun–Sep
Shearwater, Manx
Puffinus puffinus
May–Aug
Shearwater, Sooty
Puffinus griseus
May–Sep
Storm-Petrel, Wilson’s
Oceanites oceanicus
Jun–Jul
Tern, Black
Chlidonias niger
Tern, Common
Sterna hirundo
Apr–Sep
Tern, Forster’s
Sterna forsteri
Tern, Least
Sternula antillarum
May–Aug
Tern, Roseate
Sterna dougallii
Jul–Aug
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 102 of 132
Figure 2.36. Seasonality of avifauna in the Ocean SAMP area (from Paton et al. 2010).
6. Figure 2.38 shows the seasonality of waterbird use in the Ocean SAMP area, according to
bird type, and providing greater definition than could be shown in Figure 2.36, which is
useful in showing, at the same scale, seasonality of bird use in the Ocean SAMP area. Gull
use of the area is year round, while loons appear to use the Ocean SAMP area as
overwintering grounds. Pelagic birds, such as shearwaters, inhabit the Ocean SAMP area
only during the summer. In general, bird life is most diverse and abundant during fall and
spring migration, and during winter (Paton et al., 2010).
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 103 of 132
Figure 2.37. Potential use of the Ocean SAMP area by diving ducks, which suggests they forage in waters less than 20 feet deep. Since
benthic community composition is not known, this map shows potential, not preferred, foraging sites.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 104 of 132
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 105 of 132
Figure 2.38. Seasonal use of the Ocean SAMP area by gulls, loons and shearwaters
(from Paton et al. 2010).
7. Paton et al. (2010), based on both land-based and ship-based survey counts, have identified
the most common bird species using Ocean SAMP waters (Figure 2.39). Common eider are
the most abundant user of nearshore waters (≤ 3 km), followed by the herring gull and surf
scoter. Offshore waters (> 3 km) are utilized most heavily by northern gannets, followed by
Wilson’s storm-petrels, and herring gulls. Gulls appear to be one of the major users of Ocean
SAMP waters, both inshore and offshore, and throughout the seasons.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 106 of 132
Figure 2.39. Most abundant waterbirds found nearshore (top panel) and offshore (bottom
panel) in the Ocean SAMP area, based on land-based (Jan 2009–Jan 2010) and ship-
based (Mar 2009–Jan 2010) survey counts (from Paton et al. 2010).
8. Various species of tern are found throughout the Ocean SAMP area during summer months
(Paton et al. 2009; Paton et al. 2010), with more birds in the area during the post-breeding
season. For endangered roseate terns, nearly all observations were over the waters north of
Block Island, increasing with nearness to the Rhode Island coastline. Roseate terns do not
appear to significantly utilize more open, deeper water areas of Block Island Sound, Rhode
Island Sound or the Offshore Ocean SAMP area, although they have been detected roosting
on Block Island (Paton et al., 2010). Impact of tern feeding on fish ecology of the Ocean
SAMP area is not known.
9. Paton et al. (2010) report the following patterns of avian use of Ocean SAMP area waters for
the period of late November 2009 through late February 2010:
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 107 of 132
a. Both common and red-throated loons are abundant species during winter months
in the Ocean SAMP area, and population estimates suggest this area provides
critical wintering habitat for a significant number of loons. Loons were found to
be scattered throughout the area, though thinly throughout most of the central
portion of Rhode Island Sound. Densest concentrations occurred along the Rhode
Island south shore shoreline, around Block Island shoreline, and in the area west
of Block Island bordering Montauk Point and the opening to Long Island Sound.
Waters less than 35 m deep appear to be preferred, though some loons were
documented in deeper offshore waters in Rhode Island Sound.
b. Scoters and common eider were among the most abundant birds observed using
nearshore habitats during with months. They tended to concentrate around the
west side of Block Island, along the Rhode Island south shore shoreline, and
around the Sakonnet shoreline bordering Rhode Island Sound. Few were found
over the open waters of Block Island Sound, Rhode Island Sound or the Offshore
Ocean SAMP area. Scoter appeared to be most abundant during the November
through January time span; eider appeared to use the area throughout the surveyed
time span. While research suggests that seaduck primary foraging depth is less
than 20 m of water depth, Paton et al. (2010) found seaducks to consistently
forage in waters up to 25 m deep in the Ocean SAMP area.
c. Alcids (razorbills, dovekies, murres), winter migrants to the Ocean SAMP area,
were found scattered throughout the area, though densest concentrations occurred
in deeper waters south of Block Island and throughout the central portions of
Rhode Island Sound and south onto the Offshore Ocean SAMP area. These
species exhibited spatial segregation in the Ocean SAMP study area, with
razorbills specializing in northern, shallow water sections closer to land, while
common murres tend to use the central portions of the Ocean SAMP area.
Dovekies were offshore specialists that reached peak densities in southern Ocean
SAMP areas, out to the Continental Shelf.
d. Northern gannets are a common spring and fall migrant in the Ocean SAMP area.
This piscivorous specialist tends to occur in areas where depths exceed 30 m in
depth, and were observed scattered throughout the area, though their densities
peaked approximately 3 miles offshore of Block Island and/or the Rhode Island
mainland during fall and winter.
10. A large population of harlequin ducks (Histrionicus histrionicus) winters in Rhode Island
coastal waters (January to March), which is the southern extent of their range. Harlequin
ducks were generally not observed more than 50 m offshore (Caron and Paton 2007), where
they dive underwater to forage on mollusks and crustaceans. It is possible for this species to
be impacted regarding possible range constriction due to changing climate/warming
temperatures.
11. During land-based surveys, Paton et al. (2010) detected 7 species of raptors and 27 other
species of landbirds. However, with the exception of tree swallows, which are diurnal
migrants along the coast, very few songbirds or other types of landbirds were detected.
During ship-based line transect diurnal surveys only 8 species of landbirds were detected in
Rhode Island’s offshore waters (Paton et al. 2010). This is not surprising as most landbirds,
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 108 of 132
particularly songbirds, are nocturnal migrants, and are only effectively monitored by radar.
Mizrahi et al. (2010), using a radar unit on Block Island throughout 2009, were not able to
separate out landbirds from other species during radar investigations. Based on this radar
study, peak flight altitudes of targets ranged between 200-400 m above sea level, with more
birds passing over Block Island in the fall than spring. Peak migration appeared to take place
from sunset to 5 hours after sunset.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 109 of 132
Section 260. Emerging Issues
260.1. Native Species Explosions
1. Explosions of native, opportunistic species can be initiated by one or several conditions, such
as changes in primary productivity, fishing pressure, habitat availability, competition, and/or
predator-prey interactions. Changing climate can also be a main instigator of native species
explosions by either tightening or loosening restrictions due to thermal tolerances, and
allowing population levels to increase, perhaps dramatically (and see Chapter 3, Global
Climate Change, Section 330.3). Although native species explosions are known to occur in
the Ocean SAMP area, few are studied and/or well documented in the literature.
2. The ctenophore Mnemiopsis leidyi has been extensively studied in the region, where it is
known to be a voracious, non-selective consumer of plankton. In Narragansett Bay, studies
by Martin (1965, 1970) found that Skeletonema abundance declined coincident with an
increase in the abundance of the ctenophore Mnemioposis leidyi, but he found the ctenophore
in high abundance only during the later study. Increases of M. leidyi are being observed
throughout the northeastern United States continental shelf area (Link and Ford 2006), with
population increases correlated to warming waters as a primary causative factor (Kremer
1994; Costello et al. 2006). The occurrence of M. leidyi in the Ocean SAMP is not known,
and further research needs to be conducted to determine presence and impact, if any, upon
the ecology of the Ocean SAMP area.
260.2. Invasive species
1. The contemporary rate of invasive species introductions is mostly a result of human
transportation systems working at global scales. Increased speed and movement of people
and cargo due to the mechanization of travel has increased the opportunities for invasive
organisms to be introduced at scales unimaginable naturally (CRMC et al. 2007). Ship ballast
water is an obvious, though not the only, transport vector of marine invaders. Non-native
species are readily transported via packing material used by the recreational bait and
commercial shellfish industries, and via live-market fish for both aquarium use and as food
items. Winds and currents also transport organisms, as do birds and other wildlife moving
through the area.
2. Ascidians (sea squirts, tunicates) are a group of organisms that are seeing rapid human-
mediated expansion of their ranges, and are becoming firmly established in many
communities, often at the expense of displacing native species (Bullard et al. 2007). The
colonial ascidians Didemnum spp. are particularly aggressive invasive tunicates, of unknown
origin, that arrived in the New England region in the late 1980s and have become firmly
situated in the aquatic community from Eastport, Maine to Shinnecock, New York (Bullard
et al. 2007). These species have been found covering large areas of ocean bottom on Georges
Bank, in portions of Fishers Island Sound, and in a few locations in Block Island and Rhode
Island Sound (Bullard et al. 2007; Valentine et al. 2007). There are no known, consistent
predators of these invasives, which grow rapidly on hard structure to depths of 80 m. These
species have the potential to significantly alter benthic ecosystem ecology, and perhaps
several fisheries as well if they become widespread in the Ocean SAMP area.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 110 of 132
3. In response to invasive species threats, Rhode Island assembled a comprehensive plan that
lays out management strategies intended to prevent the introduction and spread of invasive
species (CRMC et al. 2007). The plan identifies a basic list of invasive and potentially
invasive species (Table 2.13) as threats to Rhode Island waters; the occurrence or abundance
of these species in the Ocean SAMP area is not well documented.
Table 2.13. Listing of invasive and potentially invasive marine species according to
CRMC et al. (2007).
Species
Scientific Name
Type of Organism
European green crab
Carcinus maenus
crustacean
Codium
Codium fragile spp.
algae
Red algae
Grateloupia turuturu
algae
SSO
Haplosporidian costalis
shellfish pathogen
MSX
Haplosporidian nelsoni
shellfish pathogen
Asian shore crab
Hemigrapsus sanguineus
crustacean
Lace bryozoan
Membranipora membranacea
bryozoan
Derma
Perkinsus marinus
shellfish pathogen
Quahog Parasite Unknown QPX
shellfish pathogen
Caulerpa
Caulerpa taxifolia
algae
Pacific oyster
Crassostrea gigas
mollusk
Chinese mitten crab
Eriocheir sinensis
crustacean
Nori
Porphyra yezoensis
algae
Veined rapa whelk
Rapana venosa
mollusk
260.3. Marine Diseases
1. Marine diseases are not widely studied in the Ocean SAMP area. However, increasing water
temperatures and changing water salinities due to changing climate are creating conditions
that are often favorable to the spread of disease organisms (Kennedy et al. 2002; and see
Chapter 3, Global Climate Change, Section 330.2).
2. Lobster shell disease was first described 80 years ago in lobster pounds, and was associated
with the bacterium Vibrio (Hess 1937). Shell disease is now seen in wild populations, and the
bacteria in the family Flavobacteriaceae are the dominant microbes found on the shell
(Chistoserdov et al. 2005). The incidence of the disease in the wild is 20 to 30%, and the
location of its emergence appears to be the area including eastern Long Island Sound, Block
Island Sound, and Narragansett Bay (Castro and Angell 2000). Lobsters become infected
with an epizootic shell disease caused by bacteria that invade the lobster’s shell through its
pores. Severity ranges from black spots that develop on the shell, to holes in the shell that
cause the shell and membrane to fuse together, and which can result in death of the
individual (Cobb and Castro 2006). The more frequently a lobster molts, the less likely it is
to have the disease, therefore younger lobsters, which molt more frequently, are more likely
to be disease free than are older lobsters. Lobster disease does not appear to be contagious,
healthy lobsters held in close proximity to diseased lobsters do not appear to contract the
disease, which suggests that the disease is environmentally mediated and/or depends upon
genetic factors in the population (Duboise and Moulton 2005). A stressful environment may
facilitate the disease by compromising the immune system, changing the pathogen
characteristics or bacterial community on the shell, or causing complications with the natural
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 111 of 132
molting process. While the source of shell disease remains unknown, it is almost certain that
one or more environmental stressors are driving the widespread appearance of shell disease,
which is causing increased mortality in lobster populations.1
3. A rickettsia-like bacterium has been found to infect the gill area of the sea scallop,
Placopecten magellanicus, in Block Island Sound (Gulka and Cheng 1985). Heavy infection
inhibits the swimming response of the scallops, which may indirectly contribute to mortality
by reducing mobility and predator avoidance (Gulka and Cheng 1985). It is not clear how
this disease spreads or the impacts to the populations of scallops in Block Island Sound.
4. Striped bass along the Atlantic coast, and particularly in the Chesapeake Bay ecosystem,
have exhibited a high prevalence—up to 75%—of mycobacteriosis, a chronic wasting
disease caused by mycobacterium (Rhodes et al. 2004; Kaattari et al. 2005). Resulting
symptoms of mycobacterios includes tumors, external lesions, swelling of the eyes,
emaciation, and stunted growth. It is estimated that as many as 60 percent of striped bass
within the Chesapeake Bay ecosystem have this disease. Striped bass mortality rates due to
mycobacteriosis are not well known, though it does appear to play a role in making striped
bass more susceptible to other sources of mortality. Furthermore, it appears that other species
are also experiencing infection, with Chesapeake Bay menhaden experiencing up to 57%
infection rates (Kane et al. 2007). Striped bass are a migratory species and regular visitors to
the Ocean SAMP area, and it is therefore likely that mycobacterium have been introduced to
the area, though its occurrence or impact on striped bass and/or the ecology of the Ocean
SAMP area is unknown.
1 Further details on lobster shell disease can be found at http://www.seagrant.gso.uri.edu/baird/2010_diseases.html.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 112 of 132
Section 270. General Policies and Regulatory Standards
270.1 General Policies
1. The Council recognizes that the preservation and restoration of ecological systems shall
be the primary guiding principle upon which environmental alteration of coastal
resources will be measured. Proposed activities shall be designed to avoid impacts and,
where unavoidable impacts may occur, those impacts shall be minimized and mitigated.
2. As the Ocean SAMP is an extension and refinement of CRMC’s policies for Type 4
Multipurpose Waters as described in the RICRMP, CRMC will encourage a balance
among the diverse activities, both traditional and future water dependent uses, while
preserving and restoring the ecological systems.
3. The Council recognizes that while all fish habitat is important, spawning and nursery
areas are especially critical in providing shelter for these species during the most
vulnerable stages of their life cycles. The Council will ensure that proposed activities
shall be designed to avoid impacts to these sensitive habitats, and where unavoidable
impacts may occur, those impacts shall be minimized and mitigated. In addition, the
Council will give consideration to habitat used by Species of Concern as defined by the
NMFS Office of Protected Resources.
4. Because the Ocean SAMP is located at the convergence of two eco-regions and therefore
more susceptible to change, the Council will work with partner federal and state agencies,
research institutions, and environmental organizations to carefully manage this area,
especially as it relates to the projected effects of global climate change on this rich
ecosystem.
5. The Council shall appoint a standing Habitat Advisory Board (HAB) which shall provide
advice to the Council on the ecological function, restoration and protection of the marine
resources and habitats in the Ocean SAMP area and on the siting, construction, and
operation of off shore development in the Ocean SAMP study area The HAB shall also
provide advice on scientific research and its application to the Ocean SAMP. The HAB is
an advisory body to the Council and does not supplant any authority of any federal or
state agency responsible for the conservation and restoration of marine habitats. The
HAB shall be comprised of nine members, five representing marine research institutions
with experience in the Ocean SAMP study area and surrounding waters, and four
representing environmental non-governmental organizations that maintain a focus on
Rhode Island. HAB members shall serve four-year terms and shall serve no more than
two consecutive terms. The Council shall provide to the HAB a semi-annual status report
on Ocean SAMP area marine resources and habitat-related issues and adaptive
management of projects in the Ocean SAMP planning area, including but not limited to:
protection and restoration of marine resources and habitats, cumulative impacts, climate
change, environmental review criteria, siting and performance standards, and marine
resources and habitat mitigation and monitoring. The Council shall notify the HAB in
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 113 of 132
writing concerning any project in the Ocean SAMP area. The HAB shall meet not less
than semi-annually with the Fishermen’s Advisory Board and on an as-needed basis to
provide the Council with advice on protection and restoration of marine resources and
habitats in the Ocean SAMP areas and potential adverse impacts on marine resources and
habitat posed by proposed projects reviewed by the Council. The HAB may also meet
regularly to discuss issues related to the latest science of ecosystem-based management in
the marine environment and new information relevant to the management of the Ocean
SAMP planning area. In addition the HAB may aid the Council and its staff in
developing and implementing a research agenda. As new information becomes available
and the scientific understanding of the Ocean SAMP planning area evolves, the HAB
may identify new areas with unique or fragile physical features, important natural
habitats, or areas of high natural productivity for designation by the Council as Areas of
Particular Concern or Areas Designated for Preservation.
270.2 Regulatory Standards
1. Ocean SAMP sea duck foraging habitats in water depths less than or equal to 20 meters
[65.6 feet] (as shown in Figure 11.7) are designated as Areas Designated for Preservation
due to their ecological value and the significant role these foraging habitats play to avian
species, and existing evidence suggesting the potential for permanent habitat loss as a
result of offshore wind energy development. The current research regarding sea duck
foraging areas indicates that this habitat is depth limited and generally contained within
the 20 meter depth contour. It is likely there are discreet areas within this region that are
prime feeding areas; however at present there is no long-term data set that would allow
this determination. Thus, the entire area within the 20 meter contour is being protected as
an Area Designated for Preservation until further research allows the Council and other
agencies to make a more refined determination. For further information on Areas
Designated for Preservation, see Chapter 11, The Policies of the Ocean SAMP.
2. Glacial moraines are important habitat areas for a diversity of fish and other marine
plants and animals because of their relative structural permanence and structural
complexity. Glacial moraines create a unique bottom topography that allows for habitat
diversity and complexity, which allows for species diversity in these areas and creates
environments that exhibit some of the highest biodiversity within the entire Ocean
SAMP area. The Council also recognizes that because glacial moraines contain valuable
habitats for fish and other marine life they are also important to commercial and
recreational fishermen. Accordingly, , the Council shall designate glacial moraines as
identified in Chapter 11, Figures 11.3 and 11.4, as Areas of Particular Concern. For
further information on Areas of Particular Concern, see Chapter 11, The Policies of the
Ocean SAMP.
3. The Council shall require, for Large -Scale Projects, modeling of circulation and
stratification to ensure that water flow patterns and velocities are not altered in ways that
would lead to major ecosystem change. The current patterns that exist within the Ocean
SAMP ecosystem play an important role in shaping ecosystem functions at all biological
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 114 of 132
and ecological scales, and in shaping physical oceanographic process such as water
column stratification.
4. Biological resource assessments shall be conducted according to the procedures outlined
in Section 1160.5 of Chapter 11, The Policies of the Ocean SAMP, and detailed in the
Site Assessment Plan and the Construction and Operation Plan sections.
5. The Council in coordination with the Joint Agency Working Group, as described in
Chapter 11, The Policies of the Ocean SAMP, shall determine requirements for
monitoring prior to, during and post-construction. Specific biological monitoring
requirements shall be determined on a project by project basis and may include but are
not limited to the monitoring of:
i. Coastal processes and physical oceanography
ii. Underwater noise
iii. Benthic ecology
iv. Avian species
v. Marine mammals
vi. Sea turtles
vii. Fish and fish habitat
6. Any Large-Scale Offshore Development, as defined in Chapter 11 in section 1160.1.1,
shall require a meeting between the HAB, the applicant, and the Council staff to discuss
potential marine resource and habitat-related issues such as, but not limited to, impacts to
marine resource and habitats during construction and operation, project location,
construction schedules, alternative locations, project minimization, measures to mitigate
the potential impacts of proposed projects on habitats and marine resources, and the
identification of important marine resource and habitat areas. For any state permit process
for a Large-Scale Offshore Development, this meeting shall occur prior to submission of
the state permit application. The Council cannot require a pre-application meeting for
federal permit applications, but the Council strongly encourages applicants for any Large-
Scale Offshore Development, as defined in Section 1160.1.1, in federal waters to meet
with the HAB and the Council staff prior to the submission of a federal application, lease,
license, or authorization. However, for federal permit applicants, a meeting with the HAB
shall be necessary data and information required for federal consistency reviews for
purposes of starting the CZMA 6-month review period for federal license or permit
activities under 15 C.F.R. part 930, subpart D, and OCS Plans under 15 C.F.R. part 930,
subpart E, pursuant to 15 C.F.R. § 930.58 (a)(2). Any necessary data and information
shall be provided before the 6-month CZMA review period begins for a proposed project.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 115 of 132
Section 280. Literature Cited
Anderson, D.M., Kaefer, B.A., McGillicuddy, D.J., Jr., Mickelson, M.J., Keay, K.E., Libby, P.S.,
Manning, J.P., Mayo, C.A., Whittaker, D.K., Hickey, J.M., He, R., Lynch, D.R., and Smith,
K.W. 2005. Initial observations of the 2005 Alexandrium fundyense bloom in southern New
England: General patterns and mechanisms. Deep-Sea Research II 52:2856-2876.
Asher, T.G., Grilli, A., Grilli, S.T., and Spaulding, M.L. 2009. Analysis of extreme wave
climates in Rhode Island waters. 10 August 2009. University of Rhode Island. Ocean SAMP
document.
Ayers, J.C. 1950. The transparency (by white Secchi disk) of the waters in and about New York
Harbor. Cornell University Status Report No. 7. (cited in Williams 1969; original not seen)
Battelle, Inc. 2002a. Fall 2001 Infauna Characterization Report, Rhode Island Region,
Long-Term Dredge Material Disposal Site Evaluation Project, U.S. Army Corps of
Engineers,
New
England
District,
Concord,
MA.
www.nae.usace.army.mil/projects.ri/riltds/ridredging.htm Accessed 25 January 2010.
Battelle, Inc. 2002b. Fall 2001 REMOTS® Characterization Report. Rhode Island Region,
Long-Term Dredge Material Disposal Site Evaluation Project, U.S. Army Corps of
Engineers,
New
England
District,
Concord,
MA.
www.nae.usace.army.mil/projects.ri/riltds/ridredging.htm Accessed 25 January 2010.
Battelle, Inc. 2003a. Benthic Infauna Data for Area E and Area W, July 2003. Long-Term
Dredge Material Disposal Site Evaluation Project, U.S. Army Corps of Engineers, New
England District, Concord, MA. www.nae.usace.army.mil/projects.ri/riltds/ridredging.htm
Accessed 25 January 2010.
Battelle, Inc. 2003b. Sediment Profile Imaging of Area E and Area W, July 2003. Long-Term
Dredge Material Disposal Site Evaluation Project, U.S. Army Corps of Engineers, New
England District, Concord, MA. www.nae.usace.army.mil/projects.ri/riltds/ridredging.htm
Accessed 25 January 2010.
Battelle, Inc. 2003c. Survey Report for the Rhode Island Region Side-Scan Sonar and
Bathymetric Survey. Long-Term Dredge Material Disposal Site Evaluation Project, U.S.
Army
Corps
of
Engineers,
New
England
District,
Concord,
MA.
www.nae.usace.army.mil/projects.ri/riltds/ridredging.htm Accessed 25 January 2010.
Beardsley, R.C., and Boicourt, W.C. 1981. On estuarine and continental shelf circulation in the
Middle Atlantic Bight. In: Evolution of Physical Oceanography, pp. 198–233. Warren, B.A.,
and Wunsch, C. (eds.) MIT Press, Cambridge, MA.
Beardsley, R.C., Chapman, D.C., Brinks, K.H., Ramp, S.R., and Shlitz, R. 1985. The Nantucket
Shoals Flux Experiment (NSFE79), I, A basic description of the current and temperature
variability. Journal of Physical Oceanography 15:713–748.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 116 of 132
Beardsley, R.C., Boicourt, W.C., and Hansen, D.V. 1976. Physical oceanography of the Middle
Atlantic Bight. In: Gross, M.G. (ed) Proceedings of the symposium Middle Atlantic
continental shelf and the New York Bight. American Museum of Natural History, New York.
pp. 3–5.
Beaugrand, G., Brander, K.M., Allistair Lindley, J., Souissi, S., and Reid, P.C. 2003. Plankton
effect on cod recruitment in the North Sea. Nature 426:661-664.
Beaugrand, G., Reid, Philip C., Ibanez, F., Alistair Lindley, J., and Edwards, M. 2002.
Reorganization of North Atlantic marine copepod biodiversity and climate. Science
296:1692-1694.
Bohaboy, E., Malek, A., and Collie, J. 2010. Baseline characterization: data sources, methods
and results. Appendix A to Chapter 5: Commercial and Recreational Fisheries. Ocean
SAMP. Rhode Island Coastal Resources Management Council, Wakefield, RI.
Boicourt, W., and Hacker, P. 1976. Circulation on the Atlantic continental shelf off the United
States, Cape May to Cape Hatteras. Memoirs of the Royal Society of Science in Liege. Set
6(10):187-200.
Boothroyd, J.C. 2009. Coarse-Grained Sediment Transport in Sounds, Bays, Estuaries, and
Lagoons. In: Sound Connections: The Science of Rhode Island & Block Island Sounds.
Proceedings of the 7th Annual Ronald C. Baird Sea Grant Science Symposium. Rhode Island
Sea
Grant,
Narragansett,
RI.
October
2008.
http://seagrantadm.gso.uri.edu/Baird_08/default.htm
Boothroyd, J.C., and Sirkin, L. 2002. The Quaternary geology of Block Island and adjacent
regions. In: The Ecology of Block Island, pp. 13–27. Paton, P., Gould, L., August, P., and
Frost, A. (eds.) The Rhode Island Natural History Survey, Kingtson, RI.
Bowen, W.D., and Harrison, G.D. 1994. Offshore diet of grey seals Halichoerus gyrpus near
Sable Island, Canada. Marine Ecology Progress Series 112:1–11.
Bowen, W.D., Lawson, J.W., and Beck, B. 1993. Seasonal and geographic variation in the
species composition and size of prey consumed by grey seals (Halichoerus grypus) on the
Scotian shelf. Canadian Journal of Fisheries and Aquatic Science 50:1768–1778.
Bricker, S.B., Longstaff, B., Dennison, W., Jones, A., Boicourt, K., Wicks, C., and Woerner, J.
2008. Effects of nutrient enrichment in the nation’s estuaries: A decade of change. Harmful
Algae 8:21–32.
Brown, R.W. 2009. Rhode Island Fisheries and the Ocean SAMP: Are we ready for the
tradeoffs? In: Sound Connections: The Science of Rhode Island & Block Island Sounds.
Proceedings of the 7th Annual Ronald C. Baird Sea Grant Science Symposium. Rhode Island
Sea Grant, Narragansett, RI. October 2008.
http://seagrantadm.gso.uri.edu/Baird_08/default.htm
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 117 of 132
Brussaard, C.P.D. 2004. Viral control of phytoplankton populations—a review. Journal of
Eukaryotic Microbiology 51:125-138.
Bullard, S., Lambert, G., Carman, M., Byrnes, J., Whitlatch, R., Ruiz, G., Miller, R., Harris, L.,
Valentine, P., and Collie, J. 2007. The colonial ascidian Didemnum sp. A: Current
distribution, basic biology and potential threat to marine communities of the northeast and
west coasts of North America. Journal of Experimental Marine Biology and Ecology
342:99-108.
Byron, C.J, and Link, J.S. in press. Stability in the feeding ecology of four demersal fish
predators in the US Northeast Shelf Large Marine Ecosystem. Marine Ecology Progress
Series.
Caron, C.M., and Paton, P.W.C. 2007. Population trends and habitat use of Harlequin Ducks in
Rhode Island. The Journal of Field Ornithology 78(3): 254-262.
Castro, K.M., and Angell, T.E. 2000. Prevalence and progression of shell disease in American
lobster, Homarus americanus, from Rhode Island waters and the offshore canyons. Journal
of Shellfish Research 19:691-700.
Chistoserdov, A.Y., Smolowitz, R., Mirasol, F., and Hsu, A. 2005. Culture dependent
characterization of the microbial community associated with epizootic shell disease lesions in
American lobster, Homarus americanus. Journal of Shellfish Research 24:741–747.
Clancy, M., and Cobb, J.S. 1997. Effect of wind and tidal advection on distribution patterns of
rock crab Cancer irroratus megalopae in Block Island Sound, RI. Marine Ecology Progress
Series 152: 217-225.
Coastal Carolina University College of Natural and Applied Sciences. N.d. Gulf Stream Rings.
Available online at: http://kingfish.coastal.edu/gulfstream/p6.htm
Collie, J., Wood, A., and Jeffries, H. 2008. Long-term shifts in the species composition of a
coastal fish community. Canadian Journal of Fisheries and Aquatic Science 65:1352-1365.
Cobb, J.S., and Castro, K.M. 2006. Shell disease in lobster: A synthesis. New England Lobster
Research Initiative. University of Rhode Island.
Codiga, D.L. 2009. Circulation in Block Island Sound, Rhode Island Sound, and Adjacent Waters,
with Emphasis on Subsurface Flows. In: Sound Connections: The Science of Rhode Island &
Block Island Sounds. Proceedings of the 7th Annual Ronald C. Baird Sea Grant Science
Symposium. Rhode Island Sea Grant, Narragansett, RI. October 2008.
http://seagrantadm.gso.uri.edu/Baird_08/Abstracts/codiga.pdf
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 118 of 132
Codiga, D.L. 2005. Interplay of wind forcing and buoyant discharge off Montauk Point: seasonal
changes to velocity structure and a coastal front. Journal of Physical Oceanography 35:
1068–1085.
Codiga, D.L., and Aurin, D.A. 2007. Residual circulation in eastern Long Island Sound:
observed transverse-vertical structure and exchange transport. Continental Shelf Research
27:103–116.
Codiga, D.L., and Rear, L.V. 2004. Observed tidal currents outside Block Island Sound:
Offshore decay and effects of estuarine outflow. Journal of Geophysical Research
doi:10.1029/2003JC001804
Codiga, D.L., and Ullman, D.S. 2010. Characterizing the physical oceanography of coastal
waters off Rhode Island: Part 1: Literature review, available observations, and a
representative model simulation. Final Report for Rhode Island Ocean Special Area
Management Plan. Coastal Resources Management Council, Wakefield, RI.
Collie, J. 2009. Long‐term data reveal climate forcing of the Rhode Island Sound fish
community structure. In: Sound Connections: The Science of Rhode Island & Block Island
Sounds. Proceedings of the 7th Annual Ronald C. Baird Sea Grant Science Symposium.
Rhode Island Sea Grant, Narragansett, RI. October 2008.
http://seagrantadm.gso.uri.edu/Baird_08/default.htm
Collie, J., Wood, A., and Jeffries, H. 2008. Long-term shifts in the species composition of a
coastal fish community. Canadian Journal of Fisheries and Aquatic Science 65:1352–1365.
Cook, G.S. 1966. Non-tidal circulation in Rhode Island Sound—drift bottle and sea bed drifter
experiements (1962–1963). TM No. 369. Naval Underwater Weapons Research Engineering
Station, Newport, RI.
Costello, J.H., Sullivan, B.K., Gifford, D.J., Van Keuren, D., and Sullivan, L.J. 2006. Seasonal
refugia, shoreward thermal amplification, and metapopulation dynamics of the ctenophore
Mnemiopsis leidyi in Narragansett Bay, RI. Limnology and Oceanography 51:1819-1831
Cowles, G.W., Lentz, S.J., Chen, C., Xu, Q., and Beardsley, R.C. 2008. Comparison of observed
and model-computed low frequency circulation and hydrography on the New England shelf.
Journal of Geophysical Research 113: C09015, doi:10.1029/2007JC004394.
CRMC, URI, RINHS. 2007. Rhode Island Aquatic Invasive Species Management Plan.
Approved by the Aquatic Nuisance Species Task Force. November 7, 2007.
www.anstaskforce.gov/State%20Plans/RI_SAMP_Approved.pdf. Accessed 25 January
2010.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 119 of 132
DeAlteris, J.T., Skrobe, L.G., Castro, K .M. 2000. Effects of mobile bottom fishing gear on
biodiversity and habitat in offshore New England waters. Northeastern Naturalist 7(4): 379-
394.
Deevey, G. B. 1952a. A survey of the zooplankton of Block Island Sound, 1943-1946. Bulletin
of the Bingham Oceanography Collection 13: 66-119.
Deevey, G. B. 1952b. Quality and composition of the zooplankton of Block Island Sound, 1949.
Bulletin of the Bingham Oceanography Collection 13: 120-164.
Drinkwater, K.F. 2005. The response of Atlantic cod (Gadus morhua) to future climate change.
ICES Journal of Marine Science 62:1327-1337.
Driscoll, N. 1996. Scientists study large storm and human effects in Block Island Sound.
Oceanus 22 March 1996. Woods Hole Oceanographic, Woods Hole, MA.
Duboise, S.M., and Moulton, K.D. 2005. Defining the etiology of epizootic shell disease: the
importance of genetic investigations of the associated bacterial and viral ecology. In: Lobster
Shell Disease Workshop Forum Series 051, pp. 26-35. Tlusty, M.F., Halvorson, H.O.,
Smolowitz, R., and Sharma, U. (eds.) New England Aquarium, Boston, MA.
Edwards, C.A., Fake, T.A., and Bogden, P.S. 2004. A numerical model investigation of spring-
summer frontogenesis at the mouth Block Island Sound. Journal of Geophysical Research
109 C12021, doi: 12010.11029/12003JC002132.
Emanuel, K. 2005. Increasing destructiveness of tropical cyclones over the past 30 years. Nature
436:686–688.
Enfield, D.B., Mestas-Nunez, A.M., and Trimble, P.J. 2001. The Atlantic Multidecadal
Oscillation and its relationship to rainfall and river flows in the continental U.S. Geophysical
Research Letters 28:2077–2080. doi:10.1029/2000GL012745.
Eriksson, B.K., Rubach, A., Hillebrand, H. 2006. Biotic Habitat Complexity Controls Species
Diversity and Nutrient Effects on Net Biomass Production. Ecology 87(1):246-254.
Fahay, M.P. 1992. Development and distribution of cusk eel eggs and larvae in the Middle
Atlantic Bight with a description of Ophidion robinsi n. sp. (Teleostei: Ophidiidae).
American Society of Ichthyologists and Herpetologists 3:799–819.
First, M.W. 1972. Municipal waste disposal by shipborne incineration and sea disposal of
residues. Harvard University School of Public Health, Boston MA.
Fogarty, M.J. 1979. Assessment of the ocean quahog, Arctica islandica, resource in Rhode
Island Sound and south of Martha's Vineyard, MA. RIDEM, Division of Fisheries and
Wildlife.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 120 of 132
Frank, K.T., Perry, R.I., and Drinkwater, K.F. 1990. Predicted response of Northwest Atlantic
invertebrates and fish stocks to CO2 induced climate change. Transactions of the American
Fisheries Society 119:353–365.
French-McCay, D. and Grilli, A. 2010. Ecological Value Map (EVM) for the Rhode Island
Ocean Special Area Management Plan. Technical Report.
Fuhrman, J.A. 1999. Marine viruses and their biogeochemical and ecological effects. Nature
339: 541-548.
Gay, P.S., O’Donnell, J., and Edwards, C.A. 2004. Exchange between Long Island Sound and
adjacent
waters.
Journal
of
Geophysical
Research.
109,
C06017,
doi:
10.1029/2004JC002319.
Griscom, C.A. 1978. Currents 0.25 meters above the bottom in 10 meters of water off
Charlestown, RI during two severe winter storms—24 Jan–Feb 1978: An Environmental
Study of a Nuclear Power Plant at Charlestown, Rhode Island, Part Two. Division of Marine
Resources, Graduate School of Oceanography, University of Rhode Island.
Gulka, G., and Cheng, P. W.. 1985. Pathogenicity and infectivity of a rickettsia-like organisms in
the sea scallop, Placopecten magellanicus. Journal of Fish Diseases 8:309–318.
Hale, S.S. 2002. Marine bottom vommunities of Block Island waters. In: The Ecology of Block
Island, pp. 131-149. Paton, P., Gould, L., August, P., and Frost, A. (eds.) The Rhode Island
Natural History Survey, Kingtson, RI.
Hargraves, P.E., Maranda, L. 2002. Potentially toxic or harmful microalgae from the northeast
coast. Northeastern Naturalist 9(1):81-120.
Hays, G.C., Richardson, A.J., and Robinson, C. 2005. Climate change and marine plankton.
Trends in Ecology and Evolution 20 (6):337-344
He, R., and Wilkin, J.L. 2006. Barotropic tides on the southeast New England shelf: A view from
a hybrid data assimilative modeling approach. Journal of Geophysical Research 111,
C08002, doi: 08010.01029/02005JC003254.
Hequette, A., and Hill, P.R. 1993. Storm-generated currents and offshore sediment transport on a
sandy shoreface, Tibjak Beach, Canadian Beaufort Sea. Marine Geology 113:283–304.
Hess, E. 1937. A shell disease in lobsters (Homarus americanus) caused by chitinovorous
bacteria. Journal of the Fisheries Research Board of Canada 3:358–362.
Hicks, S.D., and Campbell, R. 1952. Report on physical oceanographic cruises #3 and #4,
Narragansett Bay and its approaches. Narragansett Marine Laboratory Report 52-16,
University of Rhode Island, Narragansett, RI.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 121 of 132
Ho, K. 1999. The chemistry and toxicity of sediment affected by oil from the North Cape spilled
into Rhode Island Sound. Marine Pollution Journal Vol. 38, Issue 4:314.
Holland, G.J., and Webster, P.J. 2007. Heightened tropical cyclone activity in the North Atlantic:
Natural variability or climate trend? Philosophical Transactions of The Royal Society A Vol.
365, No. 1860:2695-2716.
Hollman, . 1976. A histogram analysis of the annual variations of physical and chemical
parameters: 1970–1973. Environmental Atlas of Block Island and Long Island Sound Waters
1976. New York Ocean Science Laboratory, Montauk, NY
Hulsizer, E.E. 1976. Zooplankton of Lower Narragansett Bay, 1972-1973. Chesapeake Science
17(4):260-270.
Hyde, K. 2009. Seasonal and interannual variability of phytoplankton production in Rhode
Island and Block Island Sound. In: Sound Connections: The Science of Rhode Island & Block
Island Sounds. Proceedings of the 7th Annual Ronald C. Baird Sea Grant Science
Symposium. Rhode Island Sea Grant, Narragansett, RI. October 2008.
http://seagrantadm.gso.uri.edu/Baird_08/default.htm
Hyde, K.J.W., O'Reilly, J.E., and Oviatt, C.A.. 2008. Evaluation and application of satellite
primary production models in Massachusetts Bay. Continental Shelf Research 28:1340-1351.
IPCC. 2007. Climate Change 2007: Synthesis Report. Contribution of Working Groups I, II, and
III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change.
Core writing team Pachauri, R.K., and Reisinger, A. (eds.) IPCC, Geneva, Switzerland.
Kaattari, I.M., Rhodes, M.W., Kator, H., and Kaattari, S.L. 2005. Comparative analysis of
mycobaterial infections in wild striped bass Morone saxatilis from Chesapeake Bay.
Diseases of Aquatic Organisms 67: 125–132.
Kane, A.S., Stine, C.B., Hungerford, L., Matsche, M., Driscoll, C., and Baya, A.M. 2007.
Mycobacteria as environmental portent in Chesapeake Bay fish species. Emerging Infectious
Diseases 13(2): 329–331.
Kane, J. 2007. Zooplankton abundance trends on Georges Bank, 1977–2004. ICES Journal of
Marine Science. 64:909–919.
Kaputa, N.P. and Olsen, C.B. 2000. Summer hypoxia monitoring survey ‘91–’98 data review.
Long Island Sound Water Quality Monitoring Program. Connecticut Dept. of Environmental
Protection, Hartford, CT.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 122 of 132
Katz, C.H., Cobb, J.S., and Spaulding, M. 1994. Larval behavior, hydrodynamic transport, and
potential offshore-to-inshore recruitment in the American lobster, Homarus americanus.
Marine Ecology Progress Series 103:265–273.
Keller, A.A., Taylor, C., Oviatt, C.A., Dorrington, T., Holcombe, G., and Reed, L.W. 2001.
Phytoplankton production patterns in Massachusetts Bay and the absence of the 1998 winter-
spring bloom. Marine Biology 138:1051-1062.
Kenefik, A.M. 1985. Barotropic M2 tides and tidal currents in Long Island Sound: A numerical
model. Journal of Coastal Research 1(2):117–128.
Kennedy, V.S., Twillley, R., Kleypas, J.A., Cowan, J.H., Jr., and Hare, S.R. 2002. Coastal and
marine ecosystems and global climate change: Potential effects on U.S. resources. Pew
Center on Global Climate Change. Arlington, VA.
Kenney, R.D. and Vigness-Raposa, K.J. 2009. Marine mammals and sea turtles of Narragansett
Bay, Block Island Sound, Rhode Island Sound, and nearby waters: An analysis of existing
data for the Rhode Island Ocean Special Area Management Plan. DRAFT TECHNICAL
REPORT Version 2 of 31 May 2009.
Kincaid, C., Pockalny, R.A., and Huzzey, L.M. 2003. Spatial and temporal variability in flow at
the mouth of Narragansett Bay. Journal of Geophysical Research 108(C7), 3218,
doi:10.1029/2002JC001395.
King, J., and Collie, J. 2010. Geological, geophysical, benthic habitat, archaeological study in the
Rhode Island Ocean SAMP study area. Appendix A: Technical reports for the Rhode Island
Ocean Special Area Management Plan. RI Coastal Resources Management Council,
Wakefield, RI.
Kirincich, A. and Hebert, D. 2005. The structure of the coastal density front at the outflow of
Long Island Sound in spring 2002. Continental Shelf Research 25: 1097–1114.
Koppelman, L.E., Weyl, P.K., Gross, M.G., and Davies, D.S. 1976. The Urban Sea: Long Island
Sound. Special Student Design/Environmental Planning Service. Praeger, NY.
Kremer, P. 1994. Patterns of abundance for Mnemiopsis in U.S. coastal waters - a comparative
overview. ICES Journal of Marine Science 51:347-354.
LaFrance, M., Shumchenia, E., King, J., Pockalny, R., Oakley, B., Pratt, S., and Boothroyd, J.
2010. Benthic habitat distribution and subsurface geology of selected sites from the Rhode
Island Ocean Special Area Management Study Area. Technical Report #4. Rhode Island
Coastal Resources Management Council, Wakefield, RI.
Lillick, L. 1937. Seasonal studies of phytoplankton off Woods Hole, Massachusetts. Biological
Bulletin 73(3):488-503.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 123 of 132
Linder, C.A., and Gawarkiewicz, G. 1998. A climatology of the shelfbreak front in the Middle
Atlantic Bight. Journal of Geophysical Research 103: 18405–18423.
Link, J., and Ford, M.D. 2006. Widespread and persistent increase of Ctenophora in the
continental shelf ecosystem off NE USA. Marine Ecology Progress Series 320:153-159
Loder, J.W.B., Petrie, G., and Gawarkeiwicz, G. 1998. The coastal ocean off northeastern North
America: a large-scale view. The Sea 11 (Robinson, A.R., & Brink, K.H. eds.), Wiley and
Sons, NY, pp. 105-133.
Malek, A., Collie, J., LaFrance, M., and King, J. 2010. Fisheries ecology and benthic habitat in
Rhode Island and Block Island Sounds. Technical Report #14 of the Ocean Special Area
Management Plan. Rhode Island Coastal Resources Management Council, Wakefield, RI.
Malone, T.C., and Chervin, M.B. 1979. The production and fate of phytoplankton size fractions
in the plume of the Hudson River, New York Bight. Limnology and Oceanography 24:683-
696.
Mann, K.H. 2000. Ecology of Coastal Waters with Implications for Management. 2nd Ed.
Blackwell Science.
Mann, K.H., and Lazier, J.R.N. 2006. Dynamics of Marine Ecosystems. 3rd Ed. Blackwell.
Massachusetts, USA.
Mann, M.E., and Emanuel, K.A. 2006. Atlantic hurricane trends linked to climate change. Eos,
Transactions, American Geophysical Union 87:233.
Mann, K.H., and Lazier, J.R.N. 1996. Dynamics of Marine Ecosystems: Biological-Physical
Interactions in the Oceans. 2nd Edition. Blackwell Science, Inc., Cambridge MA. 394 pp.
Marston, M.F. 2008. Natural viral communities in the Narragansett Bay ecosystem. In: Science
for ecosystem-based management: Narragansett Bay in the 21st century. Desbonnet, A. and
Costa-Pierce, B.A. Springer: 419-430.
Martin, J.H. 1970. Phytoplankton–zooplankton relationships in Narragansett Bay. IV. The
seasonal importance of grazing. Limnology and Oceanography 15:413–418.
Martin, J. 1965. Phytoplankton-zooplankton relationships in Narragansett Bay. Limnology and
Oceanography 10(2):185-191.
Mau, J.-C., Wang, D.-P., Ullman, D.S., and Codiga, D.L. 2007. Comparison of observed (HF
radar, ADCP) and model barotropic tidal currents in the New York Bight and Block Island
Sound. Estuarine and Coastal Shelf Science 72:129–137.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 124 of 132
McMullen, K.Y., Poppe, L.J., Twomey, E.R., Danforth, W.W., Haupt, T.A., and Crocker, J.M.
2007. Sidescan sonar imagery, multibeam bathymetry, and surficial geologic interpretations
of the sea floor in Rhode Island Sound, off Sakonnet Point, Rhode Island. U.S. Geological
Survey Open File Report 2007-1150. http://pubs.usgs.gov/of/2007/1150/
McMullen, K.Y., Poppe, L.J., Denny, J.F., Haupt, T.A., and Crocker, J.M. 2008. Sidescan sonar
imagery and surficial geologic interpretations of the sea floor in Central Rhode Island Sound.
U.S. Geological Survey Open-File Report 2007-1366. http://pubs.usgs.gov/of/2007/1366/.
Merriman, D., and Sclar, R.C. 1952. The pelagic fish eggs and larvae of Block Island Sound.
Bulletin of the Bingham Oceanography Collection 13: 165-219.
Mizrahi, D., Fogg, R., Mararian, T., Elia, V., and La Puma,. D. 2010. Radar monitoring of bird
and bat movement patterns on Block Island and its coastal waters. Draft interim report.
Rhode Island Ocean Special Area Management Plan. University of Rhode Island,
Narragansett, RI.
Mouw, C.B., and Yoder, J.A. 2005. Primary production calculations in the Mid-Atlantic Bight,
including effects of phytoplankton community size structure. Limnology and Oceanography
50:1232-1243.
Munk, P., Larsson, P.O., Danielson, D., and Mokness, E. 1995. Larval and small juvenile cod
Gadus morhua concentrated in the highly productive areas of a shelf break front. Marine
Ecology Progress Series 125: 21–30.
NOAA Coastal Services Center. N.d. Historical Hurricane Tracks. Available online at:
http://www.csc.noaa.gov/beta/hurricanes/#
NOAA National Marine Fisheries Service, Marine Ecosystems Division. N.d. Zooplankton
monitoring:
Northeast
continental
shelf.
Available
online
at:
http://www.st.nmfs.noaa.gov/plankton/time-series/site__nmfs-sne/index.html
NOAA Tides and Currents. N.d. Center for Operational Oceanographic Products and Services.
Available online at: http://tidesandcurrents.noaa.gov/.
Nixon, S., Granger, S., Oviatt, C., Fields, L., and Mercer, J. 2010. Spatial and temporal
variability of surface chlorophyll, primary production, and benthic metabolism in Rhode
Island and Block Island Sounds. Technical Report #9 for the Ocean Special Area
Management Plan. Rhode Island Coastal Resources Management Council, Wakefield, RI.
Northeast Fisheries Science Center. 2010. Media Advisory: “Record Number of North Atlantic
Right Whales Sighted off Rhode Island”, April 23, 2010. Available online from:
http://www.nefsc.noaa.gov/press_release/2010/MediaAdv/MA1004/index.html
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 125 of 132
Nye, J.A., Link, J.S., Hare, A.J., and Overholtz, W.J. 2009. Changing spatial distribution of fish
stocks in relation to climate and population size on the Northeast United States continental
shelf. Marine Ecology Progress Series 393:111–129.
O’Donnell, J., and Houk, A.E. 2009. The Structure and Variability of the Hydrography of the
Block Island Sound. In: Sound Connections: The Science of Rhode Island & Block Island
Sounds. Proceedings of the 7th Annual Ronald C. Baird Sea Grant Science Symposium.
Rhode
Island
Sea
Grant,
Narragansett,
RI.
October
2008.
http://seagrantadm.gso.uri.edu/Baird_08/default.htm.
Olesiuk, P.F., Bigg, M.A., Ellis, G.M., Crockford, S.J., and Wigen, R.J. 1990. An assessment of
the feeding habits of harbor seals (Phoca vitulina) in the Strait of Georgia, British Columbia,
based on scat analysis. Canadian Technical Report on Fisheries and Aquatic Sciences 1730.
O'Reilly, J.E., Evans-Zetlin, C., and Busch, D.A. 1987. Primary Production, p. 220-233. In R. H.
Backus [ed.], Georges Bank. MIT Press.
Oviatt, C., and Pastore, R. 1980. Some aspects of water quality in and pollution sources to the
Providence River. Report for Region I EPA. Contract #68-04-1002. Boston, MA.
Oviatt, C.A., Hyde, K.J.W., Keller, A.A., and Turner, J.T. 2007. Production patterns in
Massachusetts Bay with outfall relocation. Estuaries and Coasts 30: 35-46.
Oviatt, C.A., Keller, A.A., and Reed, L.W. 2002. Annual primary production in Narragansett
Bay with no bay-wide winter-spring phytoplankton. Estuarine and Coastal Shelf Science 54:
1013-1026.
Paerl, H.W., Dennis, R.L., Whitall, D.R. 2002. Atmospheric deposition of nitrogen: implicatons
for nutrient over-enrichment of coastal waters. Estuaries 25(4b):677-693.
Paton, P., Winiarski, K., Trocki, C., and McWilliams, S. 2010. Spatial distribution, abundance
and flight ecology of birds in nearshore and offshore waters of Rhode Island. Interim
Technical Report for the Rhode Island Ocean Special Area Management Plan. University of
Rhode Island, Narragansett, RI.
Payne, P.M., and Selzer, L.A. 1989. The distribution, abundance and selected prey of the harbor
seal, Phoca vitulina concolor, in Southern New England. Marine Mammal Science 5(2):173–
192.
Perry, A.L., Low, P.J., Ellis, J.R., and Reynolds, J.D. 2005. Climate change and distribution
shifts in marine fishes. Science 308:1912–1915.
Pfeiffer-Herbert, A. 2009. Summary of Larval Transport in Block Island and Rhode Island Sounds.
In: Sound Connections: The Science of Rhode Island & Block Island Sounds. Proceedings of
the 7th Annual Ronald C. Baird Sea Grant Science Symposium. Rhode Island Sea Grant,
Narragansett, RI. October 2008. http://seagrantadm.gso.uri.edu/Baird_08/default.htm
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 126 of 132
Pilson, M.E.Q. 2008. Narragansett Bay amidst a globally changing climate. In: Science for
Ecosystem-based Management: Narragansett Bay in the 21st Century. Desbonnet, A., and
Costa-Pierce, B.A. (eds.) Springer. pp. 35–46.
Poppe, L., DiGiacomo-Cohen, M., Smith, S., Stewart, H., and Forfinski, N. 2006. Seafloor
character and sedimentary processes in Eastern Long Island Sound and Western Block Island
Sound. Geo-Marine Letters 26:59-68.
Pratt, S.D. 1973. Benthic fauna. Pages 5-1–5-70 In: Coastal and Offshore Environmental
Inventory: Cape Hatteras to Nantucket Shoal, pp. 5-1 – 5-70. Saila, S.B. (ed.) Marine
Publication Series No. 2., University of Rhode Island, Kingston, RI.
Ramp, S.R., Brown, W.S., and Beardsley, R.C. 1988. The Nantucket Shoals Flux Experiment 3.
The alongshelf transport of volume, heat, salt and nitrogen. Journal of Geophysical Research
93:14,039–14, 054.
Reinert, S.E., Lapham, E., and Gaffett, K. 2002. Landbird migration on Block Island: community
composition and conservation implications for an island stopover habitat. In: Paton, P.W.,
Gould, L.L., August, P.V., and Frost, A.O. (eds), The Ecology of Block Island. Proceedings
of the Rhode Island Natural History Survey Conference, October 28, 2000. The Rhode Island
Natural History Survey, Kingston, RI. pp. 151–168.
Rhoads, D., McCall, P., and Yingst, J. 1978. Disturbance and production on the estuarine
seafloor. American Scientist 66:577-586.
Rhoads, D.C., and Germano, J.D. 1986. Interpreting long-term changes in benthic community
structure: a new protocol. Hydrobiologia 142:291-308.
Rhodes, M.W., Kator, H., Kaattari, I., Gauthier, D., Vogelbein, W., and Ottinger, C.A. 2004.
Isolation and characterization of mycobacteria from striped bass Morone saxatisis from the
Chesapeake Bay. Diseases of Aquatic Organisms. 61: 41–51.
Richards, S.W., Mann, J.M., and Walker, J.A. 1979. Comparison of spawning seasons, age,
growth rates, and food of two sympatric species of searobins, Prionotus carolinus and
Prionotus evolans, from Long Island Sound. Estuaries 2(4):255–268.
Richardson, A.J., and Schoeman, D.S. 2004. Climate impact on plankton ecosystems in the
northeast Atlantic. Science 305:1609-1612.
Richardson, D.E., Hare, J.A., Overholtz, W.J. and Johnson, D.L. in press. Development of long-
term larval indices for Atlantic herring (Clupea harengus) on the northeast U.S. Continental
Shelf. ICES Journal of Marine Science.
Ridoux, V., Spitz, J., Vincent, C., and Walton, M.J. 2007. Grey seal diet at the southern limit of
its European distribution: combining dietary analyses and fatty acid profiles. Journal of the
Marine Biological Association United Kingdom 87:225–264.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 127 of 132
Riley, G. 1952. Phytoplankton of Block Island Sound, 1949. Bulletin of the Bingham
Oceanography Collection 13:40-64.
Riley, G.A., and Conover, S.M. 1967. Phytoplankton of Long Island. Sound 1954-1955. Bulletin
of the Bingham Oceanographic Collection. 19:5-34.
Roff, J.C., and Evans, M.J.S. 2002. Frameworks for marine conservation—non-hierarchical
approaches and distinctive habitats. Aquatic Conservation: Marine and Freshwater
Ecosystems 12:635-648
Rose, G.A. 2005. On distributional response of North Atlantic fish to climate change. ICES
Journal of Marine Science 62:1360–1374.
Saila, S.B., Pratt, S.D., and Polgar, T.T. 1972. Dredge Spoil Disposal in Rhode Island Sound.
Marine Experiment Station. Sea Grant. National Sea Grant. Marine Technical Report No 2.
Sanders, H.L. 1952. The herring (Clupea harengus) of Block Island Sound. Bulletin of the
Bingham Oceanographic Collection 13:220–237.
Savard, W.L. 1966. The sediments of Block Island Sound. Master of Science Thesis, University
of Rhode Island.
Schroeder, C.L. 2000. Population status and distribution of the harbor seal in Rhode Island
waters. Master of Science Thesis, University of Rhode Island Graduate School of
Oceanography.
Shcherbina, A.Y., and Gawarkiewicz, G.G. 2008. A coastal current in winter: Autonomous
underwater vehicle observations of the coastal current east of Cape Cod. Journal of
Geophysical Research 113, C07030, doi:10.1029/2007JC004306.
Shonting, D.H. 1969. Rhode Island Sound square kilometer study 1967: flow patterns and kinetic
energy distribution. Journal of Geophysical Research 74:3386–3395.
Shonting, D.H., and Cook, G.S. 1970. On the seasonal distribution of temperature and salinity in
Rhode Island Sound. Limnology and Oceanography 15:100–112.
Signell, R.P. 1987. Tide and wind-forced currents in Buzzards Bay, Massachusetts. M.S. Thesis.
Massachusetts Institute of Technology.
Smayda, T.J. 2008. Complexity in the eutrophication-harmful algal bloom relationship, with
comment on the importance of grazing. Harmful Algae 8:140-151.
Smayda, T.J. 1973. A survey of phytoplankton dynamics in coastal waters from Cape Hatteras to
Nantucket. In: Coastal and Offshore Environmental Inventory: Cape Hatteras to Nantucket
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 128 of 132
Shoals. Occasional Publication No. 5. Graduate School of Oceanography, University of
Rhode Island, Narragansett, RI.
Smayda, T.J. 1957. Phytoplankton studies in Lower Narragansett Bay. Limnology and
Oceanography 2(4): 342-359.
Smith, F.E. 1950. The benthos of Block Island Sound. I. The invertebrates, their quantities and
their relations to the fishes. Ph.D. Thesis. Yale University, New Haven, CT.
Spaulding, M. 2007. http://www.crmc.ri.gov/samp_ocean/Wind_Energy_RI_EBC.pdf; accessed
11 February 2010.
Staker, R.D., and Bruno, S.F. 1977. Phytoplankton in coastal waters off Eastern Long Island
(Block Island Sound) Montauk, N.Y. New York Ocean Science Laboratory.
Staroscik, A.M., and Smith, D.C. 2004. Seasonal patterns in bacterioplankton abundance and
production in Narragansett Bay, Rhode Island, USA. Aquatic Microbial Ecology 35: 275-
282.
Steimle, F.W., Jr. 1982. The benthic invertebrates of Block Island Sound. Estuarine, Coastal
and Shelf Science 15:1–16.
Steimle, F.W., Jr. 1990. Benthic macrofauna and habitat monitoring on the Continental Shelf of
the Northeastern United States. I. Biomass. NOAA Technical Report NMFS 86. U.S.
Department of Commerce, Washington, DC.
Stone, B.D., and Borns, H.W., Jr. 1986. Pleistocene glacial and interglacial stratigraphy of New
England, Long Island, and adjacent Georges Bank and Gulf of Maine. In: Quaternary
Glaciations in the Northern Hemisphere, pp. 39–52. Sibrava, V., Bowen, D.Q., and
Richmond, G.M. (eds.) Pergamon Press, Oxford, UK.
Sullivan, B.K., Gifford, D.J., Costello, J.H., and Graff, J.R. 2008. Narragansett Bay ctenophore-
zooplankton-phytoplankton dynamics in a changing climate. In: Science for ecosystem-based
management Narragansett Bay in the 21st century. pp. 485–498. Desbonnet, A., and Costa-
Pierce, B.A. (eds.) Springer, NY.
Suttle, C.A. 2005. Viruses at sea. Nature 437: 356-361.
Taylor, M.H., Holzwarth-Davis, T., Bascunan, C. and Manning, J.F. 2009. Description of the
2008 oceanographic conditions on the Northeast U.S. Continental Shelf. U.S. Department of
Commerce, Northeast Fisheries Science Center, Reference Document 09-12.
Theroux, R.B., and Wigley, R.L. 1998. Quantitative composition and distribution of the
macrobenthic invertebrate fauna of the Continental Shelf ecosystems of the Northeastern
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 129 of 132
United States. NOAA Technical Report NMFS 140. U.S. Department of Commerce, Seattle,
WA.
Uchupi, E., Driscoll, N., Ballard, R.D., and Bolmer, S.T. 2001. Drainage of late Wisconsin lakes
and the morphology of later Quaternary stratigraphy of the New Jersey-southern New
England continental shelf and slope. Marine Geology 172:117–145.
Ullman, D.S. and Codiga, D.L. 2010. Characterizing the physical oceanography of coastal waters
off Rhode Island: Part 2: New observations of water properties, currents and waves. Final
Report for Rhode Island Ocean Special Area Management Plan. Coastal Resources
Management Council, Wakefield, RI.
Ullman, D.S., and Codiga, D.L. 2004. Seasonal variation of a coastal jet in the Long Island
Sound outflow region based on HF radar and Doppler current observations. Journal of
Geophysical Research 109, C07S06, doi: 10.1029/2002JC001660.
Ullman, D.S., and Cornillon, P.C. 2001. Continental shelf surface thermal fronts in winter off the
northeast U.S. coast. Continental Shelf Research 21:1139–1156.
Ullman, D. 2009. Surface Current Patterns in Block Island Sound and Adjacent Waters. In:
Sound Connections: The Science of Rhode Island & Block Island Sounds. Proceedings of the
7th Annual Ronald C. Baird Sea Grant Science Symposium. Rhode Island Sea Grant,
Narragansett, RI. October 2008. http://seagrantadm.gso.uri.edu/Baird_08/default.htm
U.S. Army Corps of Engineers. 2002. Final Report. Fall 2001 Water Column Characterization
Report. Rhode Island Region Long-Term Dredged Material Disposal Site Evaluation Project.
U.S. Army Corps of Engineers New England District, Concord, MA.
Valentine, P., Collie, J., Reid, R., Asch, R., Guida, V., and Blackwood, D. 2007. The occurrence
of the colonial ascidian Didemnum sp. on Georges Bank gravel habitat—Ecological
observations and potential effects on groundfish and scallop fisheries. Journal of
Experimental Marine Biology and Ecology 342:179-181.
Webster, P.J., Holland, G.J., Curry, J.A., and Chang, H.-R. 2005. Changes in tropical cyclone
number, duration and intensity in a warming environment. Science 309:1844–1846.
Weinbaur, M.G., Rassoulzadegan, F. 2004. Are viruses driving microbial diversification and
diversity? Environmental Microbiology 6: 1-11.
Williams, A.S. 1969. Prey selection by harbor seals in relation to fish taken by the Gulf of Maine
sink gillnet fishery. Master of Science Thesis. University of Maine.
Williams, R.G. 1967. The physical oceanography of Block Island Sound. A review report.
Technical Memorandum No. 2213–3367. U.S. Navy Underwater Sound Laboratory, New
London, CT.
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 130 of 132
Wilson, S.J.K, Fredette, T.J., Germano, J.D., Blake, J.A., Neubert, P.L.A., and Carey, D.A. 2009.
Plan-view photos, benthic grabs, and sediment-profile images: Using complementary
techniques to assess response to seafloor disturbance. Marine Pollution Bulletin 59:26-37.
Wommack, K.E., and Colwell, R.R. 2000. Virioplankton: viruses in aquatic ecosystems.
Microbiology and Molecular Biology Reviews 64: 69-114.
Wood, S.A. 2000. Summary of harbor seal (Phoca vitulina concolor) food habits in Mid-coast
Maine: Summer 2000. Report to the Marine Environmental Research Institute 1–11.
Worm, B., Sandow, M., Oschlies, A., Lotze, H.K., and Myers, R.A. 2005. Global patterns of
predator diversity in the open oceans. Science 309:1365–1369.
Yin, J.H. 2005. A consistent poleward shift of the storm tracks in simulations of 21st century
climate. Geophysical Research Letters 32: L18701, DOI:10.1029/2005GL023684.
Zajac, R.N. 2009. The ecology and dynamics of benthic communities in Block Island Sound and
Rhode Island Sound: A short review and prospectus. In: Sound Connections: The Science of
Rhode Island & Block Island Sounds. Proceedings of the 7th Annual Ronald C. Baird Sea
Grant Science Symposium. Rhode Island Sea Grant, Narragansett, RI. October 2008.
http://seagrantadm.gso.uri.edu/Baird_08/default.htm
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 131 of 132
Appendix I. Siting Analysis- Ecological Value Map
1. A second tool developed to help identify areas most suitable for offshore renewable energy
development is the Ecological Value Map (EVM) created by French-McCay and Grilli
(2010). As part of the EVM framework, French-McCay and Grilli (2010) modeled the
ecological value of the Ocean SAMP area by inputting geospatial data describing the
geophysical environment, fish and wildlife species distribution, ecosystem and habitat
characteristics, as well as human uses, such as fishing activity collected by Ocean SAMP
researchers. For this analysis, French-McCay and Grilli (2010) defined ‘ecological value’ to
include both the intrinsic value of biodiversity and the socioeconomic value associated with
the goods and services provided by the marine ecosystem (e.g. fishing activity). See French-
McCay and Grilli (2010) for more information on the development and application of EVM.
2. The process used by French-McCay and Grilli (2010) is illustrated in Figure 2.40. First,
separate EVMs were generated for individual species based on aggregation data collected and
modeled over a 100 meter grid across the Ocean SAMP area (the same grid used by the TDI
analysis described in Section 830.2).2 The species specific EVMs were then combined to
create group EVMs, resulting in EVMs for the following categories: benthic ecosystems,
pelagic ecosystems, fish, birds, sea turtles, marine mammals, bats and fisheries. This grid is
the same grid used by the TDI analysis described in Section 830.2. French-McCay and Grilli
(2010) used alternative weighing schemes when combining species maps into group maps to
reflect relative intrinsic and service values, as well as uncertainties in the underlying data.
The researchers then combined all category EVMs, across all resources, to create a composite
EVM for the entire Ocean SAMP area. In the end, the EVM framework provides a tool to
help identify portions of the Ocean SAMP area that have greater ecological value.
Understanding where these zones of greatest ecological value exist in the Ocean SAMP area
may help in determining appropriate sites suitable for an offshore renewable energy
development.
3. To complement the EVM framework, French-McCay and Grilli (2010) also performed a
principal component and cluster analysis on the maps of species distribution to identify
homogeneous areas within the Ocean SAMP boundary and generate an Ecological Topology
Map of the Ocean SAMP area. To accomplish this, French-McCay and Grilli (2010) used
principal component analysis to identify what factors best explain species distribution (e.g.
bathymetry, water temperature, fishing activity). The researchers then use cluster analysis to
identify similar zones within the Ocean SAMP area, in terms of biodiversity and ecological
structure, and generate an ecological topology map. This type of analysis may also provide
a useful tool when siting offshore renewable energy facilities, as it provides information on
what factors are influencing biological distributions in the Ocean SAMP area. For more
information on the principal component and cluster analysis used please see French-McCay
and Grilli (2010).
2 To quantify distributions and relative densities of specific species, French‐McCay and Grilli (2010) applied the
wildlife movement (migration and behavior) model (WILDMAP™). This model is based on life history information,
nesting/breeding and foraging locations, and available observational data for the species evaluated. The model
predictions are then ground‐truthed by presence/absence, abundance, frequency and spatial observational data.
For more information on the WILDMAP model used to predict usage by marine life see (ASA 2010).
Ocean Special Area Management Plan
5-4-2011 Approved
Ocean SAMP Chapter 2
Page 132 of 132
Figure 2.40. Framework for Ecological Valuation Mapping as applied to the Ocean SAMP (French-
McCay and Grilli 2010).