Ecosystem Status Report for the Northeast Large Marine Ecosystem
11. Status Determinations
11.1. Overfishing
Exploited fish and shellfish populations are classified as overfished if their biomass is less than one half of their biomass at maximum sustainable yield. Overfishing is said to occur if the current estimated fishing mortality rate exceeds the rate that is estimated to result in maximum sustainable yield.
Currently a total of 9 NES stocks out of 32 recently assessed are classified as overfished (Figure 11.1).
These include Southern New England winter flounder, ocean pout, halibut, Gulf of Maine cod, Northern windowpane flounder, Cape Cod-Gulf of Maine yellowtail flounder, witch flounder, Georges Bank cod, and Georges Bank yellowtail (Figure 11.2).
In addition, overfishing is occurring for 6 species (Northern windowpane flounder, Cape Cod-Gulf of Maine yellowtail flounder, witch flounder, Georges Bank cod, Georges Bank yellowtail and Gulf of Maine haddock (Figure 11.2).
The greatest problem exists in the mixed species trawl fisheries where bycatch is a significant issue and fishing rates cannot be fully controlled on all parts of the species complex simultaneously.
Currently, no stocks managed by the Mid-Atlantic Fishery Management council are classified as overfished (Figure 11.3) nor are any of the jointly managed species so classified (Figure 11.4).
11.2 Threatened or Endangered Species and Species of Concern
Special considerations are required for species that are threatened or endangered by human activities even when these species are not directly targeted by the fisheries. Legal mandates and authorities for protection of these species fall primarily under the Marine Mammal Protection Act, the Endangered Species Act, and other pieces of legislation including the Magnuson-Stevens Fishery Conservation and Management Act and the Migratory Bird Treaty Act. In addition, the National Marine Fisheries Service designates certain fish species as Species of Concern requiring special consideration in management. Similarly, the U.S. Fish and Wildlife designates Bird Species of concern.
Marine mammal species listed as endangered that occur in the Northeast U.S. Continental Shelf Large Marine Ecosystem (NES LME) include the blue, humpback, North Atlantic right, fin, sei and sperm whales (Table 11.1, below) The status of the western North Atlantic right whale is of particular concern. This population is currently thought to number around 400 individuals. They are highly susceptible to both collisions with ships and entanglement in fixed fishing gear, resulting in serious injuries and deaths (see Section 10). Current efforts to reduce these risks include sighting surveys for whales during times when they are congregated, wide dissemination of whale locations to mariners, restrictions on the configurations of fixed gill net, lobster and other pot gear, deployment of disentanglement teams, and support for researchers working on new gear and sensing technologies that could further reduce these risks. Four species are designated under the Marine Mammal Protection Act has having Strategic Status or as being depleted and requiring special management consideration.
Table 11.1. Marine Mammals listed under the Endangered Species Act as Endangered or Threatened and species listed under Strategic Status by the National Marine Fisheries Service as requiring special management consideration. | |||
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Common Name | Scientific Name | Region | Classification Status |
North Atlantic right whale | Eubalaena glacialis | Western North Atlantic | Endangered |
Humpback whale | Megaptera novaeangliae | Gulf of Maine | Endangered |
Fin whale | Balaenoptera physalus | Western North Atlantic | Endangered |
Sei whale | Balaenoptera borealis | Nova Scotia | Endangered |
Blue whale | Balaenoptera musculus | Western North Atlantic | Endangered |
Sperm whale | Kogia sp. | North Atlantic | Endangered |
Pilot whale, long-finned | Globicephala sp. | Western North Atlantic | Strategic Status |
Harbor porpoise | Phocoena phocoena | Gulf of Maine/Bay of Fundy | Strategic Status |
Bottlenose dolphin | Tursiops truncatus | Western North Atlantic, coastal, northern migratory | Strategic Status: depleted |
Atlantic white-sided dolphin | Lagenorhynchus acutus | Western North Atlantic | Strategic Status |
The relative status of other marine mammal species found on the Northeast Continental Shelf is depicted in Figure 11.5 (D. Palka, NEFSC, personal communication). The plot shows the estimated recovery factor (Fr) for these species (Fr ranges from 0 to 1 with 1 indicating a complete recovery; the outer circle in the polar plot corresponds to a value of 1). Species within the inner most circle as classified as endangered. While many cetacean species are classified as low to moderate with respect to recovery, seals species have increased. Grey seals and harbor seals increased dramatically over the last several decades with potentially important implications. Seals prey on some fish species and in some areas, conflict has arisen over predation by seals on commercially important fish species.
Five species of threatened or endangered sea turtles can be found in the NES LME including green, hawksbill, Kemp’s ridley, leatherback, and loggerhead turtles. The Endangered Species Act listing for each of these species is provided in Table 11.2 (below). Threats to sea turtles include disruption of nesting sites, incidental capture in fishing gear, and ship collisions. The latter two impacts are of concern for species occurring in the NES LME.
The distribution of many sea turtles follows well-defined oceanographic features, including fronts associated with the Gulf Stream. These fronts are also important habitat for large pelagic fishes, and there are consistent spatial patterns of incidental takes of sea turtles in the longline fishery off the edge of the shelf. These takes have been substantially reduced both through closures and development of modified hooks.
Table 11.2. Threats to sea turtles include disruption of nesting sites, incidental capture in fishing gear, and ship collisions. The latter two impacts are of concern for species occurring in the NES LME. | |||
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Common Name | Scientific Name | Region | Classification Status |
Leatherback | Dermochelys coriacea | Western North Atlantic | Endangered |
Kemp's Ridley | Lepidochelys kempii | Western North Atlantic | Endangered |
Hawksbill | Eretmochelys imbricata | Western North Atlantic | Endangered |
Green sea turtle | Chelonia mydas | Florida breeding colony | Endangered |
Loggerhead | Caretta caretta | Western North Atlantic | Threatened |
The distribution of many sea turtles follows well-defined oceanographic features, including fronts associated with the Gulf Stream. These fronts are also important habitat for large pelagic fishes, and there are consistent spatial patterns of incidental takes of sea turtles in the longline fishery off the edge of the shelf. These takes have been substantially reduced both through closures and development of modified hooks.
The National Marine Fisheries Service's marine stewardship role also includes responsibility for the protection of seabirds and other migratory birds. This responsibility is supported by both domestic and international directives to gain a better understanding of seabird bycatch and ways of reducing incidental takes of seabirds. Seabirds were historically hunted for food and for plumage and many species declined precipitously due to over-exploitation. By-catch in fishing operations and threats to nesting areas for some species are currently of greatest concern. The species with the largest number of takes are shearwaters and petrels followed by loons and gulls. The fisheries that were most responsible for these by-catches were bottom otter trawls and scallop dredges, followed by the drift gillnet and finally the midwater paired otter trawl. The red-throated loon (Gavia stellata), red-necked grebe (Podiceps grisegena), greater shearwater (Puffinus gravis), northern gannet (Morus bassanus), thick billed murre (Uria lomvia) , razorbill (Alca torda) , black guillemot (Cepphus grille) and the Atlantic puffin (Fratercula artica) have been identified as species at risk due to fisheries bycatch (Marie St. Martin, CUNY, personal communication).
Currently, three seabird species occurring at least seasonally in the region from New England to Cape Hatteras are listed as endangered: Bermuda Petrel, Roseate Tern, and Least Tern (Table 11.3, below). An additional 14 species are listed by the U.S. Fish and Wildlife Service as Birds of Conservation Concern requiring special management consideration. Birds of Conservation Concern are species, subspecies, and populations of all migratory nongame birds that, without additional conservation actions, are likely to become candidates for listing under the Endangered Species Act (ESA).
Table 11.3. Sea Birds listed under the Endangered Species Act as Endangered or Threatened and species listed by the U.S. Fish and Wildlife Service as Birds of Conservation Concern. | |||
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Common Name | Scientific Name | Region | Classification Status |
Bermuda petrel | Pterodroma cahow | Western North Atlantic | Endangered |
Roseate tern | Sterna dougallii | New England-Mid-Atlantic | Endangered |
Least Tern | Sternula antillarum | New England-Mid-Atlantic | Threatened |
Red-throated Loon | Gavia stellata | New England-Mid-Atlantic | FWS Birds of Conservation Concern |
Horned Grebe | Podiceps auritus | New England-Mid-Atlantic | FWS Birds of Conservation Concern |
Greater Shearwater | Puffinus gravis | New England-Mid-Atlantic | FWS Birds of Conservation Concern |
Audubon's Shearwater | Puffinus lherminieri | New England-Mid-Atlantic | FWS Birds of Conservation Concern |
Solitary Sandpiper | Tringa solitaria | New England-Mid-Atlantic | FWS Birds of Conservation Concern |
Lesser Yellowlegs | Tringa flavipes | New England-Mid-Atlantic | FWS Birds of Conservation Concern |
Whimbrel | Numenius phaeopus | New England-Mid-Atlantic | FWS Birds of Conservation Concern |
Hudsonian Godwit | Limosa haemastica | New England-Mid-Atlantic | FWS Birds of Conservation Concern |
Marbled Godwit | Limosa fedoa | New England-Mid-Atlantic | FWS Birds of Conservation Concern |
Red Knot (rufa ssp.) | Calidris canutus | New England-Mid-Atlantic | FWS Birds of Conservation Concern |
Semipalmated Sandpiper (Eastern) | Calidris pusilla | New England-Mid-Atlantic | FWS Birds of Conservation Concern |
Purple Sandpiper | Calidris maritima | New England-Mid-Atlantic | FWS Birds of Conservation Concern |
Buff-breasted Sandpiper | Tryngites subruficollis | New England-Mid-Atlantic | FWS Birds of Conservation Concern |
Short-billed Dowitcher | Limnodromus griseus | New England-Mid-Atlantic | FWS Birds of Conservation Concern |
Currently, 6 stocks of fish are listed under the Endangered Species Act as threatened or endangered: Atlantic salmon in the Gulf of Maine (endangered); Atlantic Sturgeon in the Gulf of Maine (threatened), and the New York Bight, Chesapeake Bay, and Carolina (all endangered); and shortnose sturgeon throughout its range (Table 11.4, below). An additional 12 species are listed by the National Marine Fisheries Service as Species of Special Concern. Species of Concern are species which engender concern regarding status and threats, but for which insufficient information is available to indicate a need to list the species under the Endangered Species Act.. Species of concern" status does not carry any procedural protections under the ESA.
Of these Species of Concern, only Atlantic Halibut is also listed as overfished. The remaining species on this list are either not covered by the fishery management council system or MSY-based reference points are not available to make an overfished determination or if overfishing is occurring.
Table 11.4. Fish listed under the Endangered Species Act as Endangered or Threatened and species listed by the National Marine Fisheries Service as Species of Concern. | |||
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Common Name | Scientific Name | Region | Classification Status |
Atlantic salmon | Salmo salar | Gulf of Maine | Endangered |
Atlantic sturgeon | Acipenser oxyrinchus oxyrinchus | Gulf of Maine | Threatened |
New York Bight | Endangered | ||
Chesapeake Bay | Endangered | ||
Carolina | Endangered | ||
Shortnose sturgeon | Acipenser brevirostrum | Throughout range | Endangered |
Alewife | Alosa pseudoharengus | Atlantic - Newfoundland to North Carolina | Species of Concern |
Atlantic bluefin tuna | Thunnus thynnus | Western Atlantic | Species of Concern |
Atlantic halibut | Hippoglossus hippoglossus | Atlantic - Labrador to southern New England | Species of Concern |
Atlantic wolffish | Anarhichas lupus | Atlantic - Georges Bank and western Gulf of Maine | Species of Concern |
Blueback herring | Alosa aestivalis | Atlantic - Cape Breton, Nova Scotia to St. John's River, FL | Species of Concern |
Cusk | Brosme brosme | Gulf of Maine | Species of Concern |
Dusky shark | Carcharhinus obscurus | Atlantic | Species of Concern |
Porbeagle shark | Lamna nasus | Atlantic - Newfoundland to NJ | Species of Concern |
Rainbow smelt | Osmerus mordax | Atlantic - Labrador to NJ | Species of Concern |
Sand tiger shark | Carcharias taurus | Atlantic | Species of Concern |
Thorny skate | Amblyraja radiata | Atlantic - West Greenland to NY | Species of Concern |
Warsaw grouper | Epinephelus nigritus | Atlantic - MA to Gulf of Mexico | Species of Concern |
11.3 Coastal Condition Status
Coastal Condition Reports
Periodic national assessments of the condition of coastal systems in United States have been made since 2001 (U.S. 2012; see also Houde et al, this volume). These reports represent an integrated evaluation drawing on sampling programs conducted by the U.S. Environmental Protection Agency, the U.S. Fish and Wildlife Service and the National Oceanic and Atmospheric Administration). The assessments provide standardized scores by region for five major attributes including indices of (1) water quality, (2) sediment quality, (3) coastal habitat, (4) fish tissue contaminants, and (5) nutrients [dissolved inorganic nitrogen (DIN) and phosphorus (DIP) and chlorophyll a (Chl a). Based on standardized sampling programs and expert opinion, regional status for these indicators are given qualitative scores on a scale of 1 (poor) to 5 (good). These five indicators include information on water clarity; dissolved oxygen content; sediment contaminants, toxicity and total organic carbon content; benthic diversity; coastal wetland coverage; contaminant body burdens for selected fish and invertebrate species groups; and direct measurement of DIN, DIP, and Chl a. An overall regional score is given as the un-weighted average of the five index scores. The most recent Coastal Condition Report (2012) provides information on fishery status within LMEs in the United States and a compilation of advisory reports providing information on seafood health warnings, beach closures, and other source of information on coastal status.
The most recent overall coastal condition score for the NESLME was 2.6, substantially lower than the Pacific Coast score of 3.8 (Figure 11.6). Particularly low scores for the benthic and fish contaminant indices in the Northeast result in the markedly lower value in this region relative to the west coast. This difference is attributable to the marked disparity in population densities along the two coasts and the levels of industrial activity throughout both coasts. In both systems, an overall improvement in scores since the first assessment has been noted although some caution is necessary in interpreting these since some modifications in methodology have been introduced.
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(File Modified Oct. 13 2016)
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