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Total length and frequency of all fish that were measured are reported in Table <br />11. The following fish spanned many of the 26 length categories: common carp (25 <br />categories), largemouth bass (25), white sucker (24), and flannelmouth sucker (23). <br />Green sunfish were most abundant in the 6-8 cm length category. <br />Native Fish Salvage -- To address a concern expressed by citizens during the <br />environmental assessment phase of the NNFC program (USFWS 1998x) regarding the <br />impact of nonnative fish removal on the availability of food for piscivorous birds, native <br />fish were removed from the Government Highline Canal (GHC) at the Lewis Wash <br />siphon in 1999, 2000, 2001 and 2002 and stocked into a native fish refuge (1999), an <br />isolated oxbow on the Colorado River (2000) and/or directly into the Colorado River <br />(2000, 2001, 2002). Our intent was to use the native fish in this refuge as a source of <br />fish to stock reclaimed ponds, thus providing prey items for piscivorous birds. However, <br />establishment of additional fish refuge ponds did not occur because potential stocking <br />sites were either stocked with listed fish species, reinvaded with nonnative fish species, <br />or access was denied. The abundance of native fish collected in November in each of <br />these years from the Lewis Wash siphon varied widely with 550, 12,300, 12,000, and <br /><1000 collected in 1999, 2000, 2001 and 2002, respectively (Table A-1). <br />The species composition of the 550 native fish collected in 1999 comprised <br />approximately 63% (347) roundtail chub, 33% (181) flannelmouth sucker, and 4% (22) <br />bluehead sucker. These fish were stocked in a previously reclaimed pond owned by the <br />Bureau of Land Management (BLM) near Rulison, Colorado on November 17, 1999. <br />Follow-up sampling of this reclaimed pond in July of 2000 indicated the native fish had <br />grown and at least one of the three native fish species (though unidentified) had <br />reproduced. <br />Nonnative Fish Control -- Several techniques were used to control fish in 86 <br />ponds Table 12, Figures 8, 9, 10). The most commonly used control technique was <br />chemical reclamation (69 ponds) followed by screen installation (2 inlet screens and 13 <br />outlet screens). <br />25