| Summary: | The occurrence and biomass of Pacific herring (Clupea pallasi) spawning stocks around Kodiak Island and the Alaska Peninsula in 1989 were documented by aerial surveys (not recorded here). The surveys were less than thorough because they began after spawning had started, and because of hazardous flying conditions and limited availability of charter aircraft. Therefore Age-Weight-Length-Sex data from test and commecial catches were used for analysis and are reported here. Biomass estimates used by the Kodiak Area Management staff for setting "Guideline Harvest Levels" are the best estimates ofthe size ofthe Kodiak and Alaska Peninsula herring populations. The estimated spawning biomass in 1989 was approximately 9,550 tons. Maps of historical population aggregation areas and spawning areas were compiled to identify areas of potential oil spill impact. No direct herring mortality was observed in 1989, and an influx of juvenile herring (ages 1 and 2) was noted in many bays ofthe Kodiak area Comprehensive damage assessment studies of oil impacts on herring fecundity, on egg deposition, and on egg and larvae survival and development were conducted in Prince William Sound, and the results from those studies were planned to be used to extrapolate probable damage on Kodiak Alaska Peninsula stocks. Historical data on herring length at age, from age-weight-length-sex (AWL) samples taken during herring sac roe fisheries, 1981-1990, are being compiled and analyzed to test for year, area, and possible oil spill effects on herring growth. Herring from the commercial catch and test fishing are sampled for sex, size and age annually by field crews in coastal waters of the state from Ketchikan to Kotzebue to form a data base essential to the management of the state's herring resources. This information is drawn upon by management and research biologists for monitoring and regulating harvest levels, determining run timing, entry patterns and distribution of herring arriving on the spawning grounds, monitoring sexual maturity and age composition of herring spawning populations, developing methods to forecast herring abundance and determine optimum spawning goals, and to gain a better understanding of the biology of each stock. The usefulness of this AWL data depends on the manner and accuracy in which the samples were taken.
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