USGS Fact Sheet 2013–3104: Nearshore Temperature Findings for the Colorado River in Grand Canyon, Arizona

Nearshore Temperature Findings for the Colorado River in Grand Canyon, Arizona—Possible Implications for Native Fish

By Robert P. Ross and William S. Vernieu

Abstract

Since the completion of Glen Canyon Dam, Arizona, in 1963, downstream water temperatures in the main channel of the Colorado River in Glen, Marble, and Grand Canyons are much colder in summer. This has negatively affected humpback chub (Gila cypha) and other native fish adapted to seasonally warm water, reducing main-channel spawning activity and impeding the growth and development of larval and juvenile fish. Recently published studies by U.S. Geological Survey scientists found that under certain conditions some isolated nearshore environments in Grand Canyon allow water to separate from the main-channel current and to warm, potentially providing refuge areas for the development of larval and juvenile fish.

First posted November 25, 2013

Report PDF (3 MB)

For additional information, contact:
GCMRC Staff, Southwest Biological Science Center
U.S. Geological Survey
Grand Canyon Monitoring and Research Center
2255 N. Gemini Drive
Flagstaff, AZ 86001
http://www.gcmrc.gov/

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Suggested citation:

Ross, R.P., and Vernieu, W.S., 2013, Nearshore Temperature Findings for the Colorado River in Grand Canyon, Arizona—Possible Implications for Native Fish: U.S. Geological Survey Fact Sheet 2013-3104, 4 p., https://dx.doi.org/10.3133/fs20133104.

ISSN 2327–6932 (online)