7834

• UCREFRP Catalog Number: 7834
• Author: Burdick, B. D. a. R. B. B.
• Title: Experimental Stocking Of Adult Razorback Sucker In The Upper Colorado And Gunnison Rivers.
• USFW Year: 1997.
• USFW - Doc Type: \
• Copyright Material: NO

1995, five additional adult razorback sucker that had been previously captured
from Etter Pond and held in ponds at Horsethief SWA plus the one razorback sucker
with a non-functional tag were implanted with 4.5-year radio transmitters. These
six fish were held for observation to determine possible effects from handling
and surgery.
Radiotagged fish were tracked by boat April through August 1994 and March
through October 1995. Fish were not tracked during the winter months of 1994 and
1995. An aluminum-jon boat with a 65-horsepower jet drive facilitated up- and
downstream travel to monitor movements of radiotagged fish. An ATS° digital
radio search-receiver with either an omni -directional whip or bi-directional loop
antennae was used for all tracking trips. The location of each radiotagged fish
was fixed by triangulation (Bovee 1986; Tyus 1988). Locations in the Colorado
River were recorded in river miles upstream of the confluence with the Green
River and locations in the Gunnison River were recorded upstream from the
confluence with the Colorado River. Other pertinent data collected for each
contact were general habitat type at the signal source and surface water
temperature.
Radiotelemetry provided information on dispersal patterns, movement, and
habitat use of adult razorback sucker following stocking. Radiotelemetered fish
were grouped into five categories:
1. confirmed alive: at the time of last contact fish was actively moving
upstream from the previous location.
2. confirmed mortality: the complete or partial body or carcass of the
fish was recovered--identified by it's PIT tag and/or radio tag.
3. missing or disposition unknown: the fish may still be alive but
contact with the radio signal was lost because the radio transmitter
failed: the radio transmitter is still functional and in the fishes
body cavity but the fish has moved outside the longitudinal search
route; or the fish could be occupying a water depth that exceeds the
detection capability of the radio receiver; radio transmitter could
have been expelled or lost and the fish is still alive.
4. presumed dead: fish movement has ceased for a lengthy period of time;
location of the radio signal and signal strength has remained static
for a lengthy period of time (several weeks): numerous attempts to
make the fish move by disturbing the water with boat motors, wading,
or flogging the water with boat paddles has failed; radio signal has
not moved upstream for sometime or since release.
Radio tracking data were examined to determine: 1) total number of radio
contacts per fish, 2) period or total number of days that contact was maintained
with a fish, 3) total number of river miles that a fish moved, from the most
upstream contact to the most downstream contact (total longitudinal movement),
4) maximum up- and downstream distance moved following release, 5) maximum
distance and direction that a fish moved from point of release to the point of
east contact, and 6) time of day and date. Movement analysis did not include
data if the radio signal remained in the same location and did not exhibit
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