The humpback chub, one of three species that resides within the Grand Canyon, has been classified as “threatened” under the Endangered Species Act, a shift from its former classification as “endangered.”

This reclassification, announced by a U.S. Fish and Wildlife Service press release Oct. 15, is a positive move for the species, which has stabilized or increased in the Upper Basin in Arizona. 

"Today's action is the result of the collaborative conservation that is needed to ensure the recovery of listed species," Matt Hogan, acting regional director for the USFWS. 

The humpback chub was first documented in the Lower Colorado Basin of the Grand Canyon in the 1940s and in the Colorado River Basin in the 1970s. 

"Reclassifying this distinctive fish from endangered to threatened is the result of many years of cooperative work by conservation partners in the Upper Colorado River Endangered Fish Recovery Program and the Glen Canyon Dam Adaptive Management Program,” Hogan said. 

In 2009, the U.S. Geological Survey's Grand Canyon Monitoring and Research Center estimated that there were only 6,000-10,000 of the fish remaining in the Grand Canyon, placing them in a dangerous situation. There are now more than 12,000 in the Little Colorado River and Colorado River. 

“We thank everyone involved for their efforts as we look toward addressing the remaining challenges in the Colorado River Basin,” Hogan said. 

The fish was first placed on the endangered species list in 1967.

The humpback chub is unique in its biology, as it has evolved to live and thrive in the choppy whitewater that the river is known for, specifically the areas heading for the canyon. 

The hump behind its head gives the fish its name and has proven helpful throughout its evolution as it made the fish difficult to be consumed by predators.