9447

• UCREFRP Catalog Number: 9447
• Author: Burdick, B. D.
• Title: Evaluation of Stocking Sub-Adult Colorado Pikeminnow Via Translocation in the Upper Colorado River Between Palisade and Rifle, Colorado.
• USFW Year: 2003.
• USFW - Doc Type: 105,
• Copyright Material: NO

effort). Searches for radio-tagged fish were made less frequently between mid-August and eazly-
November of both 2000 and 2001. Only periodic seazches were made from November through
May of each year. The final boat tracking was conducted inearly-June of 2002. Because the
study azea to be searched was extensive, several miles of river had to be covered on a given day.
For this reason, when contact was made with aradio-tagged fish, it was only for about 10-15
minutes. Only the general location (river mile) and general habitat type that each fish was
occupying at the time of contact was recorded.
The 5.4-mile river reach between Government Highline and Price Stubb dams is
unnavigable by boat or raft during most periods of the yeaz because of low flows. Moreover,
access to the river to launch craft is almost nonexistent. Therefore, this reach was "spot-checked"
by vehicle from various turnout points and bridges where Interstate 70 and state highways
paralleled the river. Interference from overhead electrical transmission lines often hindered
effective freaking at one site near the Cameo bridge (RM 189.7). Nonetheless, there were enough
vehicle access points in this reach close to the river that effective tracking could be conducted.
Tracking from vehicles was conducted along the Government Highline Canal immediately from
the diversion dam to the trash collecting grates at 17-3/4 Road. Vehicles were also used to
seazch for radio-tagged Colorado pikeminnow along the OMID Power Canal in the Vineland area
east of Palisade.
Antennas. Nine- and four-element aerial directional antennas (148-152 Mhz) were used
for surveillance at fixed stations; three-element antennas (AF Arnronics, Inc.®) were used from
boats. The stationary, underwater antenna consisted of an 8-cm end portion of the inner solid
copper wire of a coaxial cable (58 S~) exposed and positioned about 30-cm in the canal. Smaller-
sized, multi-filament antennas used with the high-band frequency did not compromise signal
reception or gain.
Flow and Water Temperature Data
Flow data recorded at the Cameo gage were reported for the water years 2000, 2001,
and 2002, which corresponded with radio telemetry results from this study. Onset® tidbit
temperature loggers were used to monitor and record main channel water temperature of the
Colorado River at Una (RM 216.5) and upstream from the Rifle Bridge (RM 242.7). Water
temperature data from 22 May 2000 to 13 March 2001 were recorded and downloaded in the
Upper Colorado River at RMs 216.6 (Una) and 242.7 (upstream from the Rifle Bridge). Water
temperature data recorded at Rifle from 23 Macch 2001 through February 2003 were retrieved in
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