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adult fish composition in 2004, all concurrent with a decline in native species <br />composition of 84.3% in 1997 to 45.4% in 2004 (Modde et al. 2006) <br />The Yampa population of humpback chub has declined dramatically in recent <br />decades. Tyus (1998) indicated much higher abundance and distribution of humpback <br />chub in Yampa Canyon in the 1940's than those reported by Karp and Tyus (1990) <br />between 1987-1989. The 1998-2000 population estimate by Haines and Modde (2002) <br />reported further declines in catch rates. Of note however, is the fact that the Karp and <br />Tyus (1990) and Haines and Modde (2002) sampling was done following wet years in the <br />Yampa River Basin as opposed to the current study. In 2003-2004 catch rates have <br />declined from those reported from 1998-2000 and the population appears near <br />extirpation. <br />Juvenile Fish <br />Sampling for juvenile chubs with seines is an effective technique for capturing <br />Gila spp. and monitoring juvenile success (Chart and Lentsch 1999). Identification of <br />this life stage is the major drawback to these monitoring techniques due to a lack of <br />character distinction in the population (Snyder et al. 2006). Sampling juvenile Gila spp. <br />in more individual sample years is an alternative to the current approach. Annual <br />sampling of juvenile Gila spp would facilitate better monitoring of abundance and <br />distribution. <br />The presence of juvenile Gila spp. indicates some reproduction is occurring. The <br />high incidence of these juvenile Gila spp. in given areas may lend some clues into <br />11 <br />