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Lost, a desert river and its native fishes: A historical perspective of the lower Colorado River

January 1, 2002

The Colorado River had one of the most unique fish communities in the world. Seventy-five percent of those species were found no where else in the world. Settlement of the lower basin brought dramatic changes to both the river and its native fish. Those changes began more than 120 years ago as settlers began stocking nonnative fishes. By 1930, nonnative fish had spread throughout the lower basin and replaced native communities. All resemblance of historic river conditions faded with the construction of Hoover Dam in 1935 and other large water development projects. Today, few remember what the Colorado River was really like.

Seven of the nine mainstream fishes are now federally protected as endangered. Federal and state agencies are attempting to recover these fish; however, progress has been frustrated due to the severity of human impact. This report presents testimony, old descriptions, and photographs describing the changes that have taken place in hopes that it will provide managers, biologists, and the interested public a better appreciation of the environment that shaped these unique fish.

Citation Information

Publication Year 2002
Title Lost, a desert river and its native fishes: A historical perspective of the lower Colorado River
DOI
Authors Gordon A. Mueller, Paul C. Marsh
Publication Type Report
Publication Subtype Federal Government Series
Series Title Information and Technology Report
Series Number 2002-0010
Index ID 53888
Record Source USGS Publications Warehouse
USGS Organization Fort Collins Science Center