(Posting a link here to the thread in the OR forum, just in case folks on the WA side have some info...)
Columbia River Inter-Tribal Fisheries Enforcement
Came across traffic on 155.2875 (NAC 565) in the clear the other day and didn't recognize it, so did a little looking. Apparently it's licensed to Columbia River Inter-Tribal Fisheries Enforcement, with various licenses in both OR and WA (which makes sense, being on the Columbia). I'm guessing...
forums.radioreference.com