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<br />classes of Colorado squawfish were produced during 1985B 1987. <br />Preliminary analyses of fall YOY sampling indicates that 1996 may also <br />prove to be the beginning of a strong year class. A new population estimate <br />of the adult population would allow evaluation of the contribution and <br />survival rate of the strong year classes of the mid 1980's. Size-frequency <br />analysis would provide a means to evaluate the contribution of the 1996 <br />year class. <br /> <br />Sampling will be done using a river-wide, systematic scare-and-snare effort <br />modeled after Osmundson and Burnham (1996). The river will be divided <br />into two reaches c upstream from Westwater Canyon and downstream from <br />Westwater Canyon. The upper reach will be sampled with three complete <br />passes and the downstream reach will be sampled with two complete <br />passes. All backwaters, gravel-pit ponds, and other quiet water habitats <br />within each reach will be sampled using the 'scare and snare' technique. <br />Sections of the sampling reaches with limited backwaters or other quiet <br />habitats will be sampled with shoreline electrofishing. All sections of the <br />river must be sampled to ensure that all Colorado squawfish have some <br />probability of being captured. <br /> <br />All Colorado squawfish collected will be checked for the presence of a PIT <br />. tag. Fish that do not have a PIT tag will be equipped with one. All Colorado <br />squawfish will be measured (total length, " 1 mm), weighed (" 20 g) and <br />released alive near the point of capture. . <br />Sampling will be conducted for 3 years in a row. A population estimate will <br />be calculated for each year and averaged for the 3-year period. This design <br />will provide an interval of 6.5 years between the midpoint of Osmundson and <br />Burnham's estimate and the estimate developed in this study. <br /> <br />The expanded sampling will be done 3 years in a row (1998B2000). There <br />will be a 3-year interval (2001-2003) and then another 3-year intensive <br />sampling period (2004 - 2006). This design will provide a 6-year interval <br />between midpoints of the different population estimates. <br /> <br />9. Develop procedures for estimating the humpback chub population size in <br />Yampa River. <br /> <br />The primary field effort will involve three 7-day sampling trips through <br />Yampa Canyon and one walk-through trip in Cross Mountain. The Yampa <br />River work will be integrated with the 'Catfish Removal Project' in Yampa <br />Canyon. <br /> <br />5 <br />