Status and Trends of the Grand Canyon Population of Humpback Chub

Fact Sheet 2009-3035
The science provider to the Glen Canyon Dam Adaptive Management Program



The Colorado River Basin supports one of the most distinctive fish communities in North America, including the federally endangered humpback chub (Gila cypha). One of only six remaining populations of this fish is found in Grand Canyon, Arizona. U.S. Geological Survey scientists and their cooperators are responsible for monitoring the Grand Canyon population. Analysis of recently collected data indicates that the number of Grand Canyon adult humpback chub - fish 4 years old and older and capable of reproduction - increased approximately 50 percent between 2001 and 2008. When possible model error is considered, the estimated number of adult chub in the Grand Canyon population is between 6,000 and 10,000. The most likely number is estimated at 7,650 individuals.

Study Area

Publication type Report
Publication Subtype USGS Numbered Series
Title Status and trends of the Grand Canyon population of Humpback Chub
Series title Fact Sheet
Series number 2009-3035
DOI 10.3133/fs20093035
Edition Version 1.0
Year Published 2009
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Southwest Biological Science Center
Description 2 p.
Country United States
State Arizona
Other Geospatial Grand Canyon
Google Analytic Metrics Metrics page
Additional publication details