Wednesday, May 30, 2012

Bering Sea Research Tells of Impact of Changing Ecosystem on Fisheries


A special issue of the journal Deep Sea Research II available online documents how Bering Sea fish, birds and marine mammals are changing how they eat, bear their young and make their homes in response to changes in sea ice extent and duration. The work represents newly published findings from a partnership between the NOAA Pacific Marine Environmental Laboratory, NOAA Alaska Fisheries Science Center, the Joint Institute for the Study of the Atmosphere and Ocean at the University of Washington, and several other academic and federal partners.

Because Alaska waters host some of the most commercially valuable US fisheries, scientists hope that understanding the role natural and human-influenced variations in temperature, nutrients, sea ice and other factors play in the ecosystem will enable better predictions of climate impacts that affect the economy and people of the region.

Measurements made during the six-year NOAA study show a potential impact of climate change on species ranging from zooplankton to whales living on the Bering Sea shelf. The study projects warming of southern shelf waters will limit the distribution of Arctic species such as snow crab, while the distribution and abundance of whales will change as their food source moves.

An electronic fish finder on an icebreaker was used to provide the first comprehensive observation of fish in the ice-covered portion of the Bering Sea. Researchers concluded that each winter, sea ice and the cold water that comes with it force fish southeastward, out of their summer habitat. Using similar electronic fish finders mounted on NOAA Fisheries survey vessels, researchers documented a recent increase in krill, which Pollock eat, that coincided with the end of a warm period and the start of a cold period in the eastern Bering Sea.

Articles must be purchased individually online from the publication.