Common Name: Humpback Chub
Scientific Name: Gila cypha
Appearance: Humpback chub are large olive to silvery fish with a fleshy hump located behind their head. This hump begins developing at 3-4 years of age. They can reach up to 500 mm (20 inches) in length and live 30+ years. They have small eyes and a sub-terminal mouth. During mating season the adults can develop orange to red colored patches under fins.
Diet: Humpback Chub mostly feed out of the water column eating aquatic and terrestrial arthropods, small fishes, diatoms, planktonic crustaceans and algae.
Habitat and Range: Humpback Chub prefer large riverine systems and prefer pool habitat although they have been captured in a range of habitats. Humpback Chub are have known populations in the mainstem Colorado River and four of its tributaries: the Green, Yampa, White, and Little Colorado river. They have also been introduced to Havasu Creek within the Grand Canyon.
Breeding: Humpback Chub reach maturity at 2-4 years of age. They spawn from May to July when water temperatures are14C and 24C. They prefer to spawn in slow moving water over boulder, sand and gravel substrates.
Status: Federally Listed as Threatened in 1967.
Threats: The top threat to Humpback Chub is habitat alteration due to major dams which alter flow regimens, decrease water temperature, and sedimentation. They also face threats from predation and competition with non-native fish including Northern Pike, Brown Trout, and warm water species.
Actions: Lots of work has been done to conserve this species in the Lower Colorado River Basin including translocations to upper Little Colorado River, Havasu and Shinumo creeks. There have also been alterations to flow from Hoover Dam to help control non-native species and increase sediment loads. There has been large amounts of monitoring completed in Little Colorado River to help further understand this species and populations trends.
To follow the work being done with this species click here.
U.S. Fish and Wildlife Service. Species Profile for Humpback Chub. Available at: https://www.fws.gov/nevada/protected_species/fish/species/humpback_chub.html
Kaeding L.R., M.A. Zimmerman (1983) Life history and ecology of the humpback chub in the Little Colorado and Colorado rivers of the Grand Canyon. Transactions of the American Fisheries Society, 112: 577-594.