Defining equivalent exploitation rate reduction policies for endangered salmon stocks

TitleDefining equivalent exploitation rate reduction policies for endangered salmon stocks
Publication TypeBook Chapter
Year of Publication2000
AuthorsNorris, JG, Knudsen, EE
Book TitleSustainable Fisheries Management: Pacific Salmon
PublisherCRC Press LLC
CityNew York
AbstractI use the Pacific Salmon Commission Chinook Model to define equivalent harvest reduction policies for endangered Snake River fall chinook salmon. This stock is harvested in gauntlet fashion by a number of mixed-stock fisheries from Alaska to Oregon. The overall exploitation rate on Snake River fall chinook can be reduced by a variety of means, each of which has different economic consequences for the fisheries. Eight general types of policies are considered. Four reduce harvests in single geographic regions: Alaska, British Columbia, Washington and Oregon ocean fisheries, and the Columbia River. Two policies reduce harvests in all regions in equal or scaled amounts; two reduce harvests only in US waters by equal or scaled amounts. Scaled policies reduce regional harvests in proportion to estimated regional catches of Snake River fall chinook during the period 1979-1993. Policies are deemed equivalent when the overall adult equivalent exploitation rate on the indicator stock (Lyon's Ferry Hatchery) is reduced by the same percentage. Equivalent policies are shown to be independent of assumptions about stock productivity.