9292

• UCREFRP Catalog Number: 9292
• Author: Trammell, M. and T. Chart.
• Title: Aspinall Unit Studies Nursery Habitat Studies Colorado River 1992--1996.
• USFW Year: 1998.
• USFW - Doc Type: Moab, Utah.
• Copyright Material: NO

2
~,,....
~~ ;~~ CO RM 65-55
GR RM 57-47
GREEN RNER
CO RM 30-20
COLORADO RNER
Figure 1. Nursery habitat study areas on the Colorado and Green Rivers, Utah.
At each habitat site three transects were taken; at the mouth, 1/3 and 2/3 of the length. At each
transect, depths of water plus unconsolidated substrate depth were measured at the maximum depth,
and '/z way to either side. Primary and secondary sediment types, turbidity, and sub-surface
temperatures (°C) were recorded at the midpoint of each transect.
To examine the degree-day relationship between the main channel, backwaters and squawfish,
remote temperature recorders were set to record mid-column temperatures in the main channel and
in backwaters where squawfish have been collected. Temperatures were taken every two hours. Data
from these recorders is not continuous due to equipment Ioss and failures.
Each sampling trip was coordinated with avideo-imaging overflight conducted by the BOR.
Habitat measurement data collected in the field was compared with measurements made on digitized