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: Colorado squawfish post-larval YOY substrate utilization
curve
Parameters: Substrate types based on particle size
CODE SUBSTRATE TYPE
1. Silt and clay
2. Sand
3. Gravel
4. Cobble
5. Boulder
6. Bedrock
Period: Year around
Location: All river reaches within post-larval YOY Colorado
squawfish distribution
Data utilized:
1. Green River YOY fall sampling 1979-1983
2. Colorado River YOY fall sampling 1982-83
3. Colorado River standardized sampling 1979-1981.
Data excluded:
Green River intensive and diel data because of sufficient,
more representative data .was collected during the YOY fall
sampling program.
Assumptions:
1. Catch per unit of effort reflects true habitat
preferences
2. No significant differences exist between spring and fall
seasons nor between the Green and Colorado Rivers.
Constraints:
1. Curves apply only to the upper Green and Colorado Rivers.
2. Curves apply only to backwater habitats.
3. Curves apply only to stream channel models containing
backwater habitats.
Curve Coordinates:
X (CODE) Y (SI)
1.0 1.0
2.0 1.0
3.0 0.05
4.0 0.05
5.0 0.0
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