A "Little Lake Lobster" or "mudbug" moseying its way along the streambed of the Boise River.
According to this article from Idaho Rod and Reel, Astacus trowbridgi are plentiful throughout Idaho and the Pacific NW and, although most often used as fish bait, make delicious eating. (A blog entry about the "Blue Canoe Crawdad Feed" in Murphy, ID, which took place in June, seems to confirm this.) I found there are also monster-sized crayfish in Northern Idaho of a different species, Pacifastacus, which are another common species.
But there is one variety of crawdad that is native only to Pocatello, ID.
They are not found in water, but in concert venues playing "Classic rock, blues, and alternative."
Ladies and gentleman: The Crawdads.