The main conclusion of the NFSC report is that the north-east US Continental Shelf Large Marine Ecosystem (NES LME) has undergone sustained perturbations due to environmental and anthropogenic impacts over the last four decades, resulting in fundamental changes in system structure.
Thermal conditions in the NES LME are changing due to warming of coastal and shelf waters and cooling in the northern end of the range. As a consequence, there has been a constriction of thermal habitats in the ecosystem, a northward shift in the distributions of some fish species and a shift to a warmer-water fish community.
Zooplankton community structure has also changed in concert with climate and physical processes acting over the North Atlantic Basin indicating the importance of remote forcing to the function and structure of this ecosystem, says the report.
Important changes in some components of benthic communities, notably increased abundance of sea scallops and lobster are evident, reflecting changes in fishery management and/or ecological conditions.
The direct and indirect effects of species-selective harvesting patterns have also contributed to shifts fish community composition which is now dominated by small pelagic fishes and elasmobranch species (skates and small sharks) of low relative economic value.
The trajectory of regional human population size suggests that anthropogenic pressure in the ecosystem will continue to increase.
The Northeast US Continental Shelf is classified as experiencing ecosystem overfishing according to published criteria for this designation, although improvement in the condition of several resource species has occurred and exploitation effects have been reduced for some system components over the last decade, concludes the NFSC report.
Reference
Ecosystem Assessment Program. 2009. Ecosystem Assessment Report for the Northeast US Continental Shelf Large Marine Ecosystem. US Dept Commer, Northeast Fish Sci. Cent. Ref. Doc. 09-11; 34 pages.Further Reading
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