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: Adult Colorado squawfish spawning (deposition) depth utilization
curve.
Parameters: Total water column depth (ft)
Period: 1 Jul - 15 Aug
Location: Yampa River (RM 4-31)
Date utilized:
Yampa River direct radio observations in the spawning reach during
1981, 1983 and 1984.
Data excluded:
1. Yampa River adult Colorado squawfish capture data because radio
observations are believed to be more definitive.
2. All other adult capture and radio observations ..because they are
not representative of spawning habitat selection.
3. Radio observations of adult Colorado squawfish in waters greater
than 5.5 ft and/or eddies were excluded to be incorporated into a
separate habitat selection curve called spawning (staging)
habitat.
Assumptions:
1. ,Depths measures in the location of radio telemetered fish on
cobble bars correctly represent a preference for depth.
Constraints:
1. Depth curve is applicable only to the Yampa River spawning reach
(RM 4-31) egg deposition.
2. Curves should only be used for reaches in which Colorado
squawfish have been observed congregating to spawn.
Curve coordinates:
X (ft) Y (SI)
1 0.0
3.4 1.0
5.0 1.0
6.5 0.0
-11-