The southeast Alaska fisheries is a mix stock fishery on the largest scale with roughly 1/2 of the Chinook caught there are from waters outside of Alaska.

That fishery impacts the Columbia summer and fall Chinook in away significant way. Eliminating that harvest would certainly pay dividends in returns to the Columbia and its hatcheries. That said other Columbia stocks are not impact by that fishery in any significant way.

For example the Columbia spring Chinook enter marine fisheries in only a small way. The majority of the fishing impacts on those spring Chinook happens in the river. As WN1A's fishing partner will tell us Columbia's steelhead travel to the open Pacific with few fish entering Alaskan fisheries; again typicallythe bulk of fishing impacts occur in the Columbia river itself. Similarily the basins coho feed mainly off the Washington (late stock) and Oregon (early stock) entering those coastal fisheries in significant amounts.

Something to keep in mind is that significant amounts of the smolt biomass released from the hatcheries never make it out of the rivers. Mortalities at the dams and in-river predation are not insginficant factors.

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