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F <br /> 2000 <br /> 1800 <br /> a 1600 <br /> c <br /> 1400 <br /> c <br /> 1200 <br /> w <br /> w 1000 <br /> 0 <br /> 800 <br /> L <br /> E 600 <br /> z 400 <br /> 200 pi <br /> 0 <br /> 1Z W M O r-I N M Ln l0 n W M O N M Ln l0 n W M O N M t <br /> 00 00 00 00 Ql Ql Ql Ql Ql Ql Ql Ql Ql Ql O O O O O O O O O O � � � � � <br /> M M M M M M M M M M M M M M O O O O O O O O O O O O O O O <br /> N N N N N N N N N N N N N N N <br /> Year <br /> Middle Green Lower Green Lower Colorado <br /> Figure 5. Numbers of age-0 Colorado pikeminnow collected each year from three different <br /> habitat reaches of river. A total of 2,892 Age-0 were collected in the lower Green River in <br /> 1988; the significance of strong Age-0 cohorts collected in the late 1980's was discussed in <br /> Bestgen et al. 2010. Data from Breen et al. 2014. <br /> To summarize, in the Green River Subbasin, the Colorado pikeminnow subpopulation appears to <br /> have declined somewhat and the number of adults is below the level needed for recovery. <br /> Recruitment is quite variable over time, and has not exceeded adult mortality in all years when <br /> measured over the past two decades. The number of age-0 Colorado pikeminnow is also quite <br /> variable over time, but fewer have been captured, on average, since the year 2000 than prior to <br /> 2000 (Figure 5). Colorado pikeminnow are generally distributed throughout the Green River <br /> Subbasin now nearly to the same extent that they were when they became listed, although their <br /> numbers have dwindled in the Yampa River and the reach in the White River above the Taylor <br /> Draw Dam is no longer occupied(see Baseline section). <br /> SAN JUAN RIVER <br /> Unlike the Green and upper Colorado River Basins,wild Colorado pikeminnow are extremely <br /> rare in the San Juan River. Between 1991 and 1995, 19 (17 adult and 2 juvenile)wild Colorado <br /> pikeminnow were collected in the San Juan River by electrofishing between RM 142 (the former <br /> Cudei Diversion) and Four Corners at RM 119 (Ryden 2000; Ryden and Ahlm 1996). The <br /> multi-threaded channel, habitat complexity, and mixture of substrate types in this area of the <br /> river appear to provide a diversity of habitats favorable to Colorado pikeminnow on a year-round <br /> basis (Holden and Masslich 1997). Estimates made during the seven-year research period <br /> between 1991 and 1997 suggested that there were fewer than 50 adult Colorado pikeminnow in a <br /> given year(Ryden 2000). <br /> 12 <br />