That seems like a great idea for early arriving hatchery salmon runs and hatchery steelhead which hold their condition in fresh water a lot longer than pacific salmon but the definition of 'excess' may prove difficult to gauge because the hatchery is not likely to give up a quota of the first bright arrivals for harvest (before egg collection) and the Indians are not likely to accept dark kelts for market so there is a conflict of interest there that would have to be worked out. Not impossible to work out though, perhaps a ratio or something. Better than gillnetting that's for sure.
A combination of the two approaches would make sense.
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