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Forecast of the Pacific herring biomass in Togiak district, Bristol Bay, 1993. Regional Information Report 2A93-42. Alaska Department of Fish and Game, Juneau, Alaska.

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The 1992 Togiak District spawning migration consisted of 483 million Pacific herring Clupea pallasi weighing 156,955 tons. A total of 27,756 tons were harvested by the inshore sac roe fishery and Dutch Harbor food and bait fishery. The 1993 forecast represents the first year an age-structured analysis, using fishery and run biomass age compositions with selected years of good aerial surveys, was used to generate abundance estimates. The 1993 spawning biomass of herring in the Togiak District is forecast to be 148,786 tons. An estimated 73% of the individuals and 62% of the biomass will be age-5 and -6 herring. The average size of an individual is expected to be 267 g. The 1993 recommended total allowable harvest is 29,757 tons and represents 20% of the forecasted run biomass. In accordance with the Bristol Bay Herring Management Plan, the allocation would be 1,500 tons of herring for the Togiak spawn-on-kelp fishery, 1,978 tons for the Dutch Harbor food and bait fishery, and 26,279 tons for the Togiak sac roe fishery.
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