7610

• UCREFRP Catalog Number: 7610
• Author: Wick, E. J. and J. A. Hawkins.
• Title: Colorado Squawfish Winter Habitat Study, Yampa River, Colorado, 1986-1987
• USFW Year: 1987.
• USFW - Doc Type: Final Report Year 1.
• Copyright Material: NO

0
3
Roads to the study sites were good. A county road northbound out of
Maybell provided boat launch access at RMI 79.2 . After ice formation, access
for radiotracking by four-wheel drive vehicle over two-track ranch roads was
possible along the north side of the river for 2.2 miles. Ranch roads which
originated in Maybell also provided access to the south side of the river from
RMI 80.8 to 82. Access to the Government Bridge site during radiotag
implantation was achieved by boat. The launch site was Juniper Hot Springs
(RMI 93). After ice formation, vehicle access was by County Road 17 heading
south from Highway 40 at Lay, Colorado. Ranch roads approached the river on
the north from RMI 99.4-95.7 and on the south from RMI 98.2 to 98.6.. Access to
these areas and further downstream at RMI 76-76.5, where a fish relocated, was
possible by four-wheel drive throughout the winter in spite of snowdrifts and
mud which were frequently encountered. All other fish locations were
accessable by foot a short distance from vehicle access.
METHODS
Fish collections
•
Fish collections for transmitter implantation were made on five occasions
and were completed by the end of October. Fish were collected by trammel net,
experimental gill net, electrofishing boat, and hook and line as decribed in - sex
Wick et al. (1985). Netting was conducted from canoe or 18 foot, flat-bottomed
.???
boat powered by an 80 horsepower, Mercury outboard equipped with a jet shoe
All fish collected were identified and enumerated. Catch per-unit-time was ?e1 recorded for netting and electrofishing samples. All Colorado squawfish ??e
captured were weighed to the nearest 10-50 grams and measured to the nearest
millimeter. Colorado squawfish were tagged with orange Carlin tags supplied
by the USFWS. Previously tagged Colorado squawfish (recaptures) retained their
original tags.
Implantation of radiotransmitters
Radiotransmitters used in this study were supplied by Custom Telemetry
and Consulting. Radiotransmitters used for implanting Colorado squawfish
ranged from 40.6614-40.7022 MHz. Ten of twelve tags purchased were implanted,
the remaining two were used as test tags. Eight tags had a life expectancy of
18 months and were 4.5 centimeters (cm) in length and 1.8 cm in diameter. Four
had life expectancies of 24 months and were 6 cm in length and 1.6 cm in
diameter. Pulse rates varied from 28 to 45 pulses per minute. All transmitters
were pre-tested and dipped in sterile melted beeswax prior to shipping by the
manufacturer. Upon receipt all tags were restarted and tested for two weeks
prior to implantation.
Captured adult squawfish were held in live wells and transported by boat
to the implantation site which was less than 1.5 miles from the capture site.
They were anesthetized with a solution of tricaine methanosulfate (MS 222) and
surgically instrumented with radiotransmitters according to procedures
described by Tyus and McAda (1984). Fish were held until they recovered from
the anesthetic (10-30 minutes) and released at or near their capture location.
0