Wednesday, May 18, 2011

Gulf of Alaska Bottom Trawl Survey Underway

Stock assessments of Gulf of Alaska groundfish get underway May 18 aboard the fishing vessels Ocean Explorer and Sea Storm, chartered by scientists from the National Oceanic and Atmospheric Administration for the 12th biennial survey.

Each vessel is identified with clearly visible “NOAA Research” or “US Research” signs posted on either side of the vessel’s superstructure, indicating that it is permitted specifically for scientific surveys, NOAA officials said.

Guy Fleischer, deputy director of Alaska Fisheries Science Center’s Resource Assessment and Conservation Division, said NOAA wants the public to be aware of the survey. These chartered trawlers sometimes show up only occasionally along the coast and many communities are caught unawares and may be concerned until they realize it’s just us NOAA fisheries biologists doing our regular survey, he said.

Both vessels will leave Dutch Harbor May 18 and begin sampling operations near the Islands of Four Mountains, about 180 miles southwest of Dutch Harbor. Sampling will continue as the vessels move eastward along the continental shelf and slope to the U.S. –Canada border near Dixon Entrance.

The voyage will last about 90 days and will be split into four legs, with breaks at Sand Point, Kodiak and Seward to exchange crews, re-provision and take on fuel. Both vessels are to complete their charters and offload in Ketchikan between August 10th and August 15th.

Once the survey is complete, scientists will finalize the data they collected on fishing effort, catch rates and biological characteristics of the fish populations and generate fishery-independent estimates of geographic and depth distribution, abundance and population size and age composition by the end of September.

The stock assessment modelers will then combine that information with data from the fishery and results of previous surveys to update the stock assessments produced annually for the North Pacific Fishery Management Council to manage fish stocks in the Gulf of Alaska. The council determines each year in December the allowable groundfish harvest quotas for the Gulf of Alaska, as well as the Bering Sea and Aleutian Islands.