6022

• UCREFRP Catalog Number: 6022
• Author: Bulkley, R. V., Charles R. Berry, Jr., Richard Pimental and Tamara Black.
• Title: Tolerance and Preferences of Colorado River Endangered Fishes To Selected Habitat Parameters
• USFW Year: 1981.
• USFW - Doc Type: Final Completion Report.
• Copyright Material: NO

0
iv
LIST OF FIGURES
i
Page
Figure
1. Electronic shuttlebox for thermal perference
studies (after Neill et al. 1972) ............................ 6
2. The TDS gradient device with positions of density/TDS
interfaces and location of airstones. Length = 2.4 m,
width = 45.7 cm, height = 30.5 cm ............................ 12
3. Relative frequency distribution of temperatures
selected by razorback suckers. Pooled 15-min data
during second day and night for fish acclimated to
8, 14, 20, and 26°C. Numbers above each vertical
bar provide day (D) and night (N) range of individual
modes, mean of individual modes + 2 standard errors
(darkened box) and + 1 standard deviation (clear box)........ 19
4. Humpback chub relative frequency distribution in
8 locations within a horizontal thermal gradient
chamber. (Fish were acclimated to WC and placed
in chamber with a uniform water temperature of WC).
Data on 10 fish pooled for first hour, one observa-
tion/minute.. 24
5. Relative frequency distribution of selected temper-
atures by humpback chubs. Data pooled for first
hour, one observation/minute for fish acclimated
to 14, 20, and 26°C ......................................... 26
6. Relative frequency distribution of selected
temperatures by bonytail chubs. Data pooled
for first hour, one observation/minute for fish
acclimated to 14, 20, and 26°C ............................... 28
7. Relative frequency distribution of selected
temperatures by hybrid humpback-roundtail chubs
acclimated to 20°C. Data pooled for first hour, 30
one observation/minute ......................................
8. Relative frequency distribution of selected
temperatures by juvenile Colorado squawfish. Data
pooled for third hour, one observation/minute for
fish acclimated to 14, 20, and 26°C. See Figure
3 for explanation of figure ................................ 32
9. Relative frequency distribution of selected
temperatures for adult Colorado Squawfish. Data
pooled for third hour, one observation/minute for
fish acclimated to 14, 20, and 26°C ........................ 33
0