6037

• UCREFRP Catalog Number: 6037
• Author: U.S. Fish and Wildlife Service.
• Title: Endangered Colorado River Habitat Utilization Curves-Draft.
• USFW Year: 1984.
• USFW - Doc Type: \
• Copyright Material: NO

Title: Humpback chub adult (greater than 200 mm TL) substrate
utilization curve.
Parameters: Numeric range of values for substrate types.
Code Substrate type
1. Silt and clay
2. Sand
3. Gravel
4. Cobble
5. Boulder
6. Bedrock
Period: Year around
Data utilized:
Colorado River RARE file substrate type at point of capture
data, 1979-1981.
Data excluded:
Green River and Yampa data due to limited sample size.
Assumptions:
~1. Substrates in the vicinity of adult humpback chub
captures reflect a substrate preference.
2. Humpback chub substrate preferences are the same for the
Green and Yampa Rivers.
Constraints:
1. Curve applicable to only deep canyon areas in Colorado,
Green and Yampa Rivers.
Curve Coordinates:
X (Code) Y (SI)
+1 .0 0.5
2.0 ls0
6.0 1.0
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