HAINES, Alaska—The frigid waters of the Chilkat River in southeast Alaska have teemed with fall-running salmon on their journey home to spawn for as long as Jones Hotch Jr. can remember.

Now in his 70s, Hotch is the tribal president of the sovereign Chilkat Indian Village in Klukwan, a small community on the 52-mile river 18 miles south of the U.S.–Canada border.