DENVER (AP) — The U.S. Fish and Wildlife Service has reclassified a rare Colorado River Basin fish called the humpback chub from endangered to threatened status after a decades-old effort to stabilize its populations.

The fish with a fleshy bump behind its head is one of about a dozen that are native to the Colorado River system and four that are currently endangered _ a designation it received in the late 1960s.

Federal officials say the numbers have stabilized but that the fish needs continued protections in the Grand Canyon and parts of Utah and Colorado. It once had a broader range in the Colorado River Basin but dam construction and the introduction of non-native predator species led to local populations becoming extinct.