Effects of Water Temperature, Turbidity, and Rainbow Trout on Humpback Chub Population Dynamics

Fact Sheet 2019-3049
By:  and 
Edited by: Phil Frederick



Humpback chub (Gila cypha Miller 1946), found only in the Colorado River Basin, was one of the first species to be given full protection under the Endangered Species Act of 1973. Habitat alterations, such as changes in flow and water temperature caused by dams, and the introduction of nonnative fish have contributed to population declines in humpback chub and other native fish. These habitat alterations provide ideal conditions for the nonnative sport fish, rainbow trout (Oncorhynchus mykiss Walbaum 1792). Managers have long sought to balance recovery of humpback chub with a viable rainbow trout fishery. However, finding this balance requires understanding how environmental conditions and rainbow trout have affected humpback chub populations. Recent findings indicate that the Colorado River can be managed for rainbow trout while maintaining a healthy humpback chub population in Grand Canyon National Park.

Suggested Citation

Yackulic, C.B., and Hull, J.B., 2019, Effects of water temperature, turbidity, and rainbow trout on humpback chub population dynamics: U.S. Geological Survey Fact Sheet 2019–3049, 4 p., https://doi.org/10.3133/fs20193049.

ISSN: 2327-6932 (online)

Study Area

Publication type Report
Publication Subtype USGS Numbered Series
Title Effects of water temperature, turbidity, and rainbow trout on humpback chub population dynamics
Series title Fact Sheet
Series number 2019-3049
DOI 10.3133/fs20193049
Year Published 2019
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Southwest Biological Science Center
Description 4 p.
Country United States
State Arizona
Other Geospatial Lower Colorado river
Google Analytic Metrics Metrics page
Additional publication details