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<br />EXECUTIVE SUMMARY <br /> <br />Habitat use data for Colorado squawfish were obtained by tracking five radio tagged adult <br />fish during July through October, 1996. In addition to the squawfish, five northern pike and <br />five channel catfish were also tagged and located on a bi-weekly basis. All fish were <br />monitored from River Mile (RM) 77 upstream to RM 103. <br /> <br />Colorado squawfish used pool habitat the majority of the time that they were observed in <br />the field, Movement from one pool to another through riffles was documented, however, <br />no fish remained in the riffles during an observation period, Colorado squawfish moved <br />during the late evening to near midnight for what appeared to be feeding within the local <br />habitat where they were first monitored on the 24 hour observations. No fish during <br />those 24 hour observations was seen moving through a riffle section but moved actively <br />within a longer pool or run habitat. During the course of the study one Colorado <br />squawfish moved upstream approximately 7 miles. That same fish moved 6 12 miles <br />downstream to near the point of initial capture by the end of the study. This fish moved <br />through numerous shallow riffles and one diversion structure during the lowest flows of <br />the year. A second Colorado squawfish was noted to move 5 miles downstream and <br />remain in that downstream location for the study period, <br /> <br />Channel catfish used pool habitat primarily and run habitat secondarily, Most of those <br />fish remained within the same river mile of contact but two had moved approximately 4 <br />miles downstream at the end of the study in late October. <br /> <br />Northern pike had less movement than any of the other species, They did show <br />movement during 24 hour periods that were similar to Colorado squawfish with <br />movement activity peaking after dusk and in late evening to midnight. They did move <br />from a stationary location upstream and then back downstream to the location where first <br />observed. Most of the northern pike stayed within the same river mile where the initial <br />capture and tagging took place and did not move outside that area, Most movements <br />were less than 12 mile but they did move from pool through a riffle to a pool during the <br />course of the study, <br /> <br />Data collection for 1997 should continue as in 1996. Radio telemetry should be <br />conducted every other week from late July until October. When possible, 24 hour <br />observations should be made once per month on each Colorado squawfish, <br /> <br />Habitat use information should be based on ground contacted fish locations, Contacts by <br />air overflights should be used for general river location to assist ground crews in locating <br />implanted fish, Ground crews were able to triangulate locations of implanted fish to <br />verify actual river locations. In some instances the actual locations differed by several <br />miles from the location reported by air surveys. The large difference, with no apparent <br />pattern in occurrence, indicate that air contacts without ground truthing cannot be used to <br />categorize habitat used by the fish. <br /> <br />Yampa River Radio Telemetry Report <br />Miller Ecological Consultants, Inc, <br /> <br />Page v <br />January 23, 1997 <br />