9668

• UCREFRP Catalog Number: 9668
• Author: Crowl, T. A. and e. al.
• Title: Bonytail Draft 1998 Annual Report, February 2000.
• USFW Year: 2000.
• USFW - Doc Type: Logan, UT.
• Copyright Material: NO

120 GLOW VELOCITY
---- ---------------- ----------------- -
MEDIUM VELOCITY
100
D

-------

----------------- NHIGH VELOCITY
W
> 80 i,
......................... ........................
60

O 40

0-01 ...............................................
20
0
DEEP MID SURFACE
Figur DEPTH
1.8.
h selection by bonytail in flow experiments without substrate and with red shiners
present (daytime only).
e
Dept
Substrate and Flow Experiments With Red Shiners
Substrate selection was independent of time of observation as determined by an R x C
test. Bonytail were found exclusively at deep depths in the cobble substrate (Fig. 1.2).
Because of the lack of variation, we did not perform statistical analysis on these data.
Bonytail were not displaced by the presence of red shiners. In controls, bonytail chose
cobble substrate, deep depths, and effective velocities of 0.0 m/s during the day 75% of
the time in low velocity treatments, 80% in medium velocity treatments, and 90% of the
time in high velocity treatments. In controls at night, bonytail chose cobble substrate,
deep depths and effective velocities of 0.0 m/s 86% in low velocity treatments and 88%
of the time in medium velocity treatments. High velocity treatment data were
unavailable. During both day and night observations, in all velocity treatments, when
red shiners were present, bonytail chose cobble substrate and deep depths with
effective velocities of 0.0 m/s 100% of the time.
23