Economic Analysis of Critical Habitat Designation in the Colorado River Basin for the Razorback Sucker, Humpback Chub, Colorado Squawfish, and Bonytail April 1994

• Description: Economic Analysis of Critical Habitat Designation in the Colorado River Basin for the Razorback Sucker, Humpback Chub, Colorado Squawfish, and Bonytail April 1994
• State: CO
• Basin: Colorado Mainstem
• Date: 4/1/1994
• Title: Economic Analysis of Critical Habitat Designation in the Colorado River Basin for the Razorback Sucker, Humpback Chub, Colorado Squafish, and Bonytail April 1994
• Water Supply Pro - Doc Type: Report/Study

c. Humpback Chub
Historically the humpback chub occupied portions of the mainstem Colorado River and at
least four of its tributaries: the Green, the Yampa, the White, and the Little Colorado.
However, the extent of its original distribution throughout the Colorado River Basin is not
known with certainty. A considerable number of alterations were made to the Colorado
River system before the 1940s, especially in the Lower Basin, and humpback chub may have
disappeared from some river reaches before their existence was documented.
USFWS is designating 7 reaches of the Colorado River system (Figure I -2 -3) as critical
habitat for the humpback chub. In the Upper Basin, critical habitat includes portions of the
Green, Yampa, and Colorado rivers. Portions of the Colorado and Little Colorado rivers are
being designated in the Lower Basin. Of the historical range of humpback chub, 28 percent
is being designated as critical habitat.
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Figure I -2 -3. Map of Critical Habitat for the Humpback Chub.
I -8