7406

• UCREFRP Catalog Number: 7406
• Author: Bestgen, K. R.
• Title: Status Review of the Razorback Sucker,
• USFW Year: 1990.
• Copyright Material: NO

suckers radiotagged in the mainstream Colorado River near Grand
Junction in spring 1987 showed some movement (Osmundson and
Kaeding 1989a). Two of these fish moved downstream 17.1 and 19.2
km, respectively, and stayed there the remainder of the year while
a third moved upstream 11.2 km from its release site within about
a 3-week period and subsequently moved downstream to near its
release site.
Telemetry information for razorback suckers was also
collected in the Gila River, near Safford, Arizona (Marsh and
Minckley 1989c). Fourteen wild (Lake Mohave) and hatchery-reared
adults were implanted and released 24 May 1988, and nine more were
implanted, held for-recovery, and later released on 12 October
1988. Movements of fish were mostly downstream; only three fish
moved upstream. Most were thought to have died in a short time
(32 days or less) as indicated by recovery of transmitters near
fish remains. Some fish may have moved downstream to San Carlos
Reservoir where transmitter signals were undetectable in deeper
water (Marsh and Minckley 1989c).
In winter, razorback suckers in the Green River remained
within 5 km study sections and exhibited no distinct diel pattern
of movement (Valdez and Masslich 1989)._ Local movements occurred
between closely-spaced microhabitats, but fish often remained
sedentary for several hours within a microhabitat.
Movements of razorback suckers in Lake Mohave were evaluated
with mark and recapture data (Marsh and Minckley 1989a). Of
twenty-five fish recaptured two to seven years after tagging
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