7168

• UCREFRP Catalog Number: 7168
• Author: Medel-Ulmer, L.
• Title: Abstract - Movement and Reproduction of the Razorback Sucker ‎(
• USFW Year: 1980.
• Copyright Material: YES

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MOVEMENT AND REPRODUCTION OF THE RAZORBACK SUCKER (XYRAUCHEN TEKANUS
INHABITING SENATOR WASH RESERVOIRS I14PERIAL COIVTY9 CALIFOR11IA c
The movements of five adult razorback suckers within a reservoir of the
Colorado River were monitored through two spawning periods from JaiMary to
April. 1980 and 1981, using ultrasonic transmitters. Telemetry data indicRted
that razorback suckers congregated and spawned over two gravel areas in the
littoral zone of the reservoir in 2-18 feet of water. Substrate samples
analyzed from spawning sites at Senator Wash Reservoir and a third location
on the Colorado River revealed similar geological an(bpetrological composition.
Observations of spawning behavior and interspecific predation on eggs were
made both from shore and underwater using SCUBA. Underwater photography was
employed to document spawning habitat and behavioral observations. Eggs and
larvae from both spawning areas at Senator Wash Reservoir were collected and
photographed at various stages of development. One-hundred eggs were artificially
reared to the larval stage and data were obtained on feeding and behavior.
Possible reasons for lack of recruitment for this species in the lower Colorado
River and the requirements necessary for successful reproduction to the larval
stage are discussed.
Linda Medel-Ulmer
California State University
Long Beach.. California 90840
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