The researchers compared marine ecosystems in the northern hemisphere and mostly in high latitudes, ranging from the eastern Bering Sea and Gulf of Alaska in the North Pacific to Georges Bank and the Gulf of Maine, North Sea and the Adriatic Sea off Italy. Other ecosystems studied included the Gulf of St. Lawrence, Scotian Shelf, Newfoundland Shelf, Southern New England, Gulf of Finland, and the Baltic Sea. All of these ecosystems support commercially important fisheries.
Fisheries landings in the ecosystems studied appear to have shifted from groundfish to invertebrates, such as squid, shrimp and scallops. In many, the fish community has changed from one dominated by demersal or bottom-dwelling species to one dominated by pelagic or upper water column species. The researchers note that it is unclear if their findings are true of all marine ecosystems, or just those studied. One of the many questions raised by the comparative analyses is whether similar species in different ecosystems react to environmental conditions in similar ways, or whether the local ecosystems override global factors.
Fisheries production varies widely among ecosystems, and is affected by changing natural and human-induced factors such as climate, pollution and fishing effort. With so many factors involved, Link said scientists need to understand the relative importance of each factor in each ecosystem, something that is difficult to achieve but important for an ecosystem approach to fisheries management and conservation.
"We do a lot of science, but rarely have the opportunity to pull it all together to understand the big picture, with basin-scale comparisons, so that we
|Contact: Shelley Dawicki|
NOAA Fisheries Northeast Fisheries Science Center