link to AFSC home page
Mobile users can use the Site Map to access the principal pages

link to AFSC home page link to NMFS home page link to NOAA home page

Resource Ecology & Fisheries Management (REFM) Division

AFSC Quarterly
Research Reports
Oct-Nov-Dec 2007
ABL Reports
FMA Reports
NMML Reports
RACE Reports
REFM Reports
Quarterly Index
Quarterly Home

Resource Ecology & Ecosystem Modeling (REEM) Program

Fish Stomach Collection and Lab Analysis

During October through December 2007, fisheries observers returned 1,297 stomach samples to AFSC laboratories, and AFSC scientists collected 994 stomach samples from the eastern Bering Sea. Stomach samples were not analyzed at sea this quarter, but 2,707 stomach samples were analyzed in the laboratory. A total of 16,605 records were added to the groundfish food habits database.

By Troy Buckley, Geoff Lang, and Mei-Sun Yang

Sculpin Life History Investigations

As part of a larger study of sculpin life history, a total of 784 otoliths from the yellow Irish lord (Hemilepidotus jordani) and 682 otoliths from the warty sculpin (Myoxocephalus verrucosus) have been aged. Ageing has begun for the plain sculpin (Myoxocephalus jaok) and is ongoing for the bigmouth sculpin (Hemitripterus bolini). The maximum age for the yellow Irish lord in samples analyzed was estimated to be 28 years from a female collected in the Aleutian Islands; an age of 18 years was estimated for a female warty sculpin collected in the eastern Bering Sea.

Natural mortality values were estimated and reported in the 2007 Bering Sea-Aleutian Islands (BSAI) sculpin stock assessment based on some of this work. These values varied considerably in this group. Using Hoenig's (1983) regression equation where mortality is a function of maximum age, values ranged from 0.15 for females of the yellow Irish lord to 0.47 in females of a previously aged sculpin of the eastern Bering Sea, Gymnocanthus pistilliger. Maturity work and stomach analysis from specimens collected in both survey and fishery-dependent samples are being processed and analyzed and will be updated in a later report.

By Todd TenBrink

next >>>

            | Home | Site Map | Contact Us | FOIA | Privacy | Disclaimer | | Accessibility | Print |           doc logo