Being somewhat realistic, in Washington, you only have black bears, puma - maybe. The biggest danger is the most dangerous animal on earth, and any of the previous mentioned forms of serious social intercourse would suffice. However, if you want to be able to stop any of the aforementioned then, a short-barreled (18") 12 gauge would be the best bet. Carried in shotgun scabbard with a few slug rounds and a few buckshot.... Personally prefer a GP-100, .357 Mag with hard lead, and snake loads, in a holster picked for the type of hiking, etc., I'm doing.