I've witnessed some things like that as well it's to bad that those people can't catch fish so they hafta snag em up to bring home dinner But my buest suggestion would be for you to get hold of of WDFW or however u say it and let them know what's going on and just tell them that they should have more wordens just hanging around those popular places for people to fish and just be on the look out for any people like that.
hope this helps.

Andrew