During the second quarter of 2012, Resource Ecology and Ecosystem Modeling (REEM) program staff made preparations for summer surveys in addition to analyzing stomach samples.
Stomach sampling has begun on the trawl surveys of the Aleutian Islands, eastern Bering Sea continental shelf, and eastern Bering Sea continental slope. Preparations for collecting stomach samples during both surface and bottom trawl surveys of the Chukchi Sea also have been made.
Stomach Content ANalysis at sea (SCAN) is being conducted on both Aleutian Islands trawl survey vessels, and collection of all visually unidentifiable fishes will be returned to the lab for microscopic or genetic examination. Genetic examination of fish specimens collected from SCANned stomachs in previous years have shown that the accurate visual identification by current laboratory personnel is very robust, even for very digested fish specimens. However, genetic identification of the small percentage of fishes that are not identifiable to at least the genus level suggests that the species composition of these fishes is not well represented by the visually identified portion of the stomach contents.
Stomach samples are currently being collected and preserved from the eastern Bering Sea trawl surveys. Total survey collections will be reported at the end of the third quarter.
Laboratory analysis of groundfish stomach contents has continued. During this quarter, 3,582 stomachs from 14 predators species were analyzed from the eastern Bering Sea, and 101 stomachs from three predator species were analyzed from the Gulf of Alaska. This resulted in 15,868 records being added to the AFSC Groundfish Food Habits database. Observers collected 221 stomachs during this quarter.
By Troy Buckley, Geoff Lang, Mei-Sun Yang, Richard Hibpshman, Caroline Robinson, Sean Rohan, and Kimberly Sawyer
