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1 <br />1 <br /> <br /> <br />1 <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br />We used Pradel's survival and population rate of change model in program MARK for <br />the full 1980 to 1999 data set to estimate ~., the population rate of change. The most reasonable <br />candidate model had constant ~, and ~ and time-varying p. Survival rate was estimated at 0.69 <br />(SE 0.021) and ~, = 0.91 (SE = 0.014). This suggested an average overall population decline <br />from the joint effects of emigration, immigration, recruitment, and mortality of about 9% per year <br />during the period 1980 to 1999. A 9% decline per year would be the interpretation of a lambda <br />value of 0.91 because a value of 1.0 (1.0 - 0.91 = 0.09, or 9%) indicates no change in the <br />population rate of change. Another candidate model with time varying ~, was not interpreted <br />because estimates from the early 1980's were unreasonably small or large (>200,000). <br />Other adult fish sampling, 1996-1999.- Relatively few wild adult fish were captured in <br />other areas of the Green River basin. Only two were captured in the lower Yampa River and two <br />were captured in the lower Green River during Basinwide sampling. Four stocked fish were <br />captured in the lower Green River during that time. <br />Larvae, middle Green River.-During Basinwide sampling in 1996 to 1999, larvae were <br />sampled with light traps in both the middle and lower Green River reaches. In the middle Green <br />River, a total of 20,844 fish in 15 taxa were captured in light-trap samples from 1996 to 1999 <br />(Table 5). Of those, 10,048 (48.2 %) were native catostomids (included all unidentified fish), <br />and 247 (1.2 %) were razorback sucker larvae. We consider only native catostomids in these <br />analyses because abundance of the only other catostomid captured, introduced white sucker <br />Catostomus commersoni, was low in all years. In 1999, the 121aivae captured were sent to <br />Ouray National Fish Hatchery for possible rearing and use as brood stock. All other specimens <br />were discarded so information for other taxa was not available. Capture rates of catostomid <br />16 <br /> <br />