9592

• UCREFRP Catalog Number: 9592
• Author: Mueller, G. A., J. Carpenter and P. C. Marsh.
• Title: Cibola High Levee Pond Annual Report 2004.
• USFW Year: 2004.
• USFW - Doc Type: \
• Copyright Material: NO

The proportion of females to males is approximately 1: 1 for discernable sexes for fish <45 mm
but gradually increases with size (Figure 12). Females comprised 99% of razorback suckers
>500 cm. While we would expect the sex ratio of the largest mature fish to remain relatively
stable, the overall size of the population should increase as fish age since the population is
relatively young. The oldest razorback suckers are <14 years old, which are relatively young
adults based on the species' longevity.

100%
-
't-*' 80%
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II)
c-
o c..
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o l'll 40%
c..U)
0 1Il
... II)
Q. >< 20%
II)
U)
0% '
450

"b..!II. :-'~~Ili!:";. --

g

'll'
; 0 Females
n 'ill' he
; . Males

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475

500

525

Length (mm) (n =82)

Figure 12. The percentage of females versus males for razorback sucker
>450 mm taken from Cibola High Levee Pond.

3. COVER UTILIZATION BY BONYTAIL

Telemetry studies conducted in 2003 indicated that large (>400 mm) bonytail showed a cover
preference for large rip-rap along the high levee. We wanted to determine if smaller,
intermediate-sized fish shared a similar preference. We used several strategies to test this: 1)
telemetry equipment, (2) netting from specific cover types (3), tank tests and (4) snorkeling
observations.

Telemetry Study-Another telemetry survey was conducted examining the cover preference of
intermediate sized bonytail. The work was accomplished under contract by Arizona State
University. The final report which covered both the 2003 and 2004 efforts is presented in
Appendix A in its entirety and the summary is presented below:

Sonic transmitters were affixed to a sample often large, adult bonytail (2003) and nine smaller,
sub-adult bonytail (2004) in CHLP. Series of point and paired, directional observations showed
that adult bonytail used interstices of large rip-rap during the daytime, then came out into open

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