3010

• UCREFRP Catalog Number: 3010
• Author: Holden, P. B. and D. A. Selby.
• Title: Study to Determine the Spawning Requirements of Colorado Squawfish.
• USFW Year: 1978.
• USFW - Doc Type: Logan, UT.
• Copyright Material: NO

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moved out of the backwater into the main river where he was found approximately
. one mile downriver.

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JUNE 22 THROUGH 30 - PHASE IV CONTINUED
During this period, efforts were devoted to relocating 40.670, as well as
the remaining six tagged fish.
On June 23, 40.670 was located in a small backwater area further downriver.
June 24 through 25 were spent searching the secondary study area from the
confluence of the Green and Colorado rivers to a distance 70 miles upriver.
On June 26, a yagi-type antenna was received. It was ordered based on
growing evidence that the radio transmitters might be too weak to be picked up
with the whip antenna. Theyagi resembles a large T.V. antenna and is designed
to pick up signals from a greater distance. When tested and compared with the
whip antenna, it was found to have little effect on the sensitivity of the SR-40,
but had a noticeable increase in the sensitivity of the RF-40.
The continued downstream movement of 40.670 prompted a search of Desolation
and Gray canyons by raft in an attempt to locate the other four fish. The yagi
and whip antennas were used, along with both receivers, but no fish were located.
On June 29, 40.670 was found to have moved further downstream.
On June 30. another search was made of the Ouray-Sand Wash section using
the yagi antenna. Fish 40.670 was located further downriVer. The difference in
sensitivity of the yagi and whip antennas on receiving this fishfs signal, with
the RF-40 receiver, were negligible. This was contrary to our earlier testing
of the yagi antenna.

JULY 4 THROUGH 11 - PHASE IV CONTINUED; PHASE I RESUMED
. On July 4, it was discovered that 40.670 had left his last location. The
entire river f,'ol\l Ouray to five miles below Sand Wash was checked, without success.
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