7389

• UCREFRP Catalog Number: 7389
• Author: Marsh, P. C.
• Title: Razorback Sucker Management in Arizona.
• USFW Year: 1985.
• USFW - Doc Type: 181.
• Copyright Material: YES

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RAZORBACK SUCKER MANAGEMENT IN ARIZONA
Razorback sucker management in Arizona began in 1981 with a 10-year

memorandum of understanding between Arizona Game and Fish Department
(GFD) and U.S. Fish and Wildlife Service. Production is at Dexter
National Fish Hatchery, New Mexico, with grow-out to larger sizes both
there and at GFD Page Springs Hatchery. By 1985, more than 10 million
juveniles, fingerlings, and fry have been stocked at 28 sites on the
Gila, Salt, and Verde rivers and their tributaries. Stocking sites and
downstream riverine reaches have been monitored annually, and reservoirs
on each system were sampled in 1985. Few have been recaptured more than
a few weeks after introduction. Post-stocking studies to evaluate
dispersal and predation were carried out in 1984 and 1985. Fish 62-213
mm TL move downstream•at night. Predation by introduced catfishes
(Pylodictis olivaris, Ictalurus punctatus) has potential to remove sig-
nificant percentages of stocked fish. It is recommended that razorback
be stocked at upstream localities where predator populations are absent
or small, in winter when predation may be reduced, or where predators
have been removed or at least depleted. Introductions should be of a
few individuals over a wide time span rather than abruptly in large
groups. Intensive monitoring should be restricted to a single river
system to better use limited resources and obtain better information on
successes and/or failures. Possibilities for differential survival of
raceway versus pond-reared fish and for training in predator avoidance
should be investigated.
Paul C. Marsh
Center for Environmental Studies and
Department of Zoology
Arizona State University
Tempe, Arizona 85287