7422

• UCREFRP Catalog Number: 7422
• Author: Valdez, R. A. and W. J. Masslich.
• Title: Winter Habitat Study of Endangered Fish - Green River.
• USFW Year: 1988.
• USFW - Doc Type: Logan, Utah.
• Copyright Material: NO

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DRAFT

APPmoIX F

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PERFORMANCE OF RADIOTELEMETRY EXJUIPMEN1'

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The frequency and pulse rate of each radiotransmitter were checked by FWS prior
to transferring the tags to BIOjWEST. Also, the frequency and pulse rate were
checked by BIOjWEST prior to and immediately after implantation (Table 3).
Variation in frequency and/or pulse rate was detected in most of the
radiotransmitters with decreases in pulse rate occurring most commonly.
Generally, both the frequency and the pulse rates stabilized within about a
month after implantation, but some variation continued throughout the study and
may be attributed to fluctuating cold water temperatures.

Generally, the radio receivers provided by the FWS for this study performed
satisfactorily. There was some initial difficulty distinguishing transmitters
of very close frequencies and similar pulse rates. In one case, two of four
fish aggregated in one area had such transmitters. As the study progressed,
differences in transmissions from AVM and Smith-Root transmi tters, which
included differences in tone and duration of pulse, were more readily
recognized. This aided in identifying transmitters.

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