7347 - Laserfiche WebLink

Home Browse Search

discharge method (Hamilton and Bergersen 1984). RESULTS Five sampling trips were conducted which included 10 days of radiotracking and/or fish sampling (Table 1). Radiotracking was conducted in, May and June during spring run-off. Sampling for adult fish was conducted in May and June during spring run-off and in July and September during baseflow. Discharge was measured during baseflow in July and September. Radiotagged fish observations Two Colorado squawfish were located in the Little Snake River by radiotelemetry, both of which had over-wintered in the Yampa River within the Lily Park study area (RMI 54.0-51.0). The first Colorado squawfish, yellow Carlin tag #1029 was located by radiotelemetry in the Little Snake River on May 24 at RMI 5.7. The fish was in a large (10 X 50 meter) main-channel eddy and was monitored from 1500 to 1516 hours. Depth at fish location was 3.0 ft,. velocity was 0.0 ft/s and substrate was sand. Main-channel temperature was 18.0°C at 1528 hours. This fish was located at the same habitat on May 25, but was also using a slackwater area below an island tip. Cobble riffles were on both sides of the island. We monitored the fish from 1730 to 1800 hours while sampling the eddy with a 150 ft trammel net. The fish was caught in the eddy, at 1800 hours. On June 8, this fish was located approximately one mile upstream (RMI 6.7) of its previous location. The fish was within an eddy at the lower end of an island. Substrate in the area consisted of mostly sand imbricated cobble and gravel. Another radiotagged Colorado squawfish, orange Carlin tag #3081 was located approximately 1 mile above the Yampa River confluence (RMI 1.0) on June 8. The fish was moving upstream in 1 to 2 ft depth water in main-channel run habitat over sand substrate. Water temperature was 18.8°C at 1743 hours. Water temperature in the Yampa River just upstream of the confluence with the Little Snake River was 15.7°C at 1800 hours. Prior to being found in the Little Snake River in late May and early June, fish #1029 was located on April 7 at RMI 52.1 in the Yampa River, approximately one mile above the confluence with the Little Snake River. After using the Little Snake River in May and June, this fish was located in. the Yampa River 0.1 mile below the confluence (RMI 51.0) on June 26. On July 6, #1029 was located by USFWS personnel at the spawning area in Yampa Canyon at RMI 16.5 (personal communication, H. M. Tyus). On October 2, this fish was located by radiotelemetry in the Yampa River, Lily Park area at RMI 52.8. In the spring, on May 21, fish #3081 was in the Yampa River at RMI 46.4, downstream of its over-wintering area. On June 7, the day before this fish was located in the Little Snake River, it was located in the vampa River (RMI 49.9) 1.2 miles downstream of the Little Snake River confluence. After using the Little Snake River, on June 7, the fish moved downstream into the Yampa River to RMI 48.0 on June 27 and to RMI 46.5 on June 30, its last known location. 3