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Beginning in the spr ing of 1984, YOY monitoring will include a prerunoff monitoring component to evaluate overwintering, runoff mortality and habitat requirements during this time of year. This is viewed as a deficiency in the program at this time. As discussed several times, the Vernal Station has stored raw data on the fish composition and physical condition of backwater nursery habitat since 1979. We recommend that these data be subjected to analysis in the winter of 1984-85. The objectives of this analysis would include evaluating conditions influencing the abundance of Colorado squawfish for the six-year period 1979-84 and relating habitat conditions and the presence of other fish species to suitability of nursery habitat and survivorship. The following outlines the proposed Plan of Study for 1984: 1. Larval Studies Collections will be made by seining the lower 5 miles of the Yampa River and Green River in Echo Park; the Green River at Jensen, and the Green River above Green River, Utah; and the Colorado River from Palisade, Colorado to the Green River confluence. Collections in 1984 and 1985 will be compared to previous years data on abundance, time of year, and temperature and flow conditions. 2. YOY Monitoring Collections will be made by seining backwater habitats in the Green River, stratum F and A during April 1984. Regular fal]_ monitoring will continue throughout the mainstem Green and Colorado Rivers as in the past with the Green River effort doubled by sampling series conducted in September and in October as in the Colorado River during the past two years. 3. Spawning Surveys Because of the high payoff in determining the exact time of spawning and recapturing marked fish these su rveys would continue at the Yampa and Gray Canyon sites and at various sites in the Colorado where radio tagged .Colorado squawfish congregate. Sampling would be conducted in July and August. More physical data would be collected in 1984 at prospective spawning sites and a physical comparisons made for similarities. 4. Radiotelemetry and spring adult sampling Radiotelemetry would be limited to implanting 15 adults in the Green river section between Echo Park and Ouray and to the upper and middle reaches of the Colorado River. Since spring electrofishing collections represent a significant sampling effort, it is recommended that electrofishing be conducted in a systematic manner to serve as a monitoring program for 30