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McClane Canyon Mine Expansion and Fruita Loadout Facility Biological Assessment
<br />• Standard stormwater and spill containment BMPs for water quality would avoid
<br />increased sedimentation or contaminant loading in Reed Wash or in groundwater
<br />that may connect through the hyporheic zone.
<br />• Potentially toxic herbicides would not'be applied to control tamarisk or other invasive
<br />species Within the'100- yearfloodplain.
<br />The Project is likely to adversely affect Colorado pikeminnow critical habitat because:
<br />•. Water withdrawal from the Colorado River and /or from aquifers connected to the
<br />river by the .Proposed Action would adversely affect critical habitat designated for
<br />Colorado pikeminnows.
<br />4.3.2 Razorback Sucker
<br />4.3.2.1 Species Account and Critical Habitat
<br />Status. The razorback sucker was listed as endangered by the FWS in 1991 because of limited
<br />numbers found throughout the Colorado River Basin and minimal evidence of natural
<br />recruitment FWS (1991).
<br />Threats. Primary threats to the razorback sucker are stream flow regulation and habitat
<br />modification;-including Coldwater darn releases, habitat loss, and blocked;migration corridors, as
<br />well as competition from non- native'fish species, pesticide's, and pollution (FWS, 2002b; also
<br />see effects due to selenium discussed in Section 4.3.2.3, below). Flow recommendations 'have
<br />been developed for some wai4 in the Upper Colorado River Basin. When razorback suckers
<br />were listed, the FWS (1991) noted there was little indication of recruitment with "decreasing
<br />population trends for adult fish. Habitat alterations, including diversion and depletion of water,
<br />introduction of non - native fishes, and construction and operation of dams were cited as
<br />contributing to the observed downward trends. In addition, water development projects have
<br />depleted flows, altered flow regimes, changed water quality, and fragmented habitats which,
<br />along with changes in fish communities due to introductions of many non - native fish species,
<br />predation by non - native fishes, Joss -of habitat, and pesticides and pollutions have been cited as
<br />the causes for the species' endangered status (FWS, 2002b).
<br />Life History, Habitat. Distribution. :Historically, razorback suckers inhabited the Colorado River
<br />mainstem and -major tributaries in Arizona,' California, Colorado, Nevada, New Mexico,
<br />Wyoming and Mexico (Minckley, 1983). - The razorback sucker is most often found in quiet,
<br />muddy backwaters along the river (FWS, 1994; CDOW, 2007a). Spawning extends from April
<br />through June; spawning occurs in river bars with cobble, gravel, and sand substrates during
<br />high flows from spring runoff, .when water �temperatures are greater than 57 °F (FWS, 2002b).
<br />Juvenile rearing habitats are in quiet, warm., shallow water associated with various river and
<br />floodplain features (FWS, 2002b). Reproduction has been adversely affected by lower water
<br />temperatures due to ilimpoundrhents within the Colorado River Basin since colder water from the
<br />bottom is released downstream (FWS, 2002b).
<br />Within the Upper Colorado River Basin, naturally reproducing populations are only found' in the
<br />middle Green River in Utah and in an off - channel pond in the Colorado River near Grand
<br />Junction (FWS, 2002b). Razorback. suckers have been reintroduced to the lower 34 miles of
<br />the Gunnison River from which wild populations had been previously extirpated (FWS, 2002b),
<br />Species Recoverx. The, FWS released recovery goals for the Razorback Sucker in 2002, as an
<br />amendment and supplement to the recovery plan .of 1998. There are two recovery units, the
<br />upper basin including the Green 'River and upper Colorado River subbasins, and the lower
<br />basin, including the mainstem and its tributaries from Glen Canyon Dam downstream to the
<br />southerly International Boundary with Mexico (FWS, 2002b).
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