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<br />35 <br /> <br />event populations are lost in the Green River subbasin and/or Colorado River <br />subbasin. Any additional losses or further degradation of remaining San Juan <br />River habitats, resulting in further reductions in distribution and abundance <br />of Colorado squawfish and razorback sucker, will exacerbate problems the <br />species is currently experiencing in the San Juan River and throughout the <br />remainder of the Upper Basin. Protection and enhancement of the San Juan <br />River is needed to provide additional protection against possible extinction <br />of the Colorado squawfish and razorback sucker while reducing total dependency <br />on the Colorado and Green Rivers systems for survival and recovery. The San <br />Juan River subbasin, isolated from the Colorado and Green Rivers subbasins, <br />provides a third population of wild fish, contributing an additional essential <br />buffer against a catastrophic event (such as an oil spill) elsewhere in the <br />basin. <br /> <br />Bald eaale <br /> <br />There are several potential impacts to bald eagles that could result from <br />project construction and operation. Impacts to the existing cottonwood <br />riparian forests on the Animas and La Plata Rivers and impacts to future <br />cottonwood recruitment could affect the primary habitat used by bald eagles in <br />the project area. Reclamation conducted studies to determine project impacts <br />to wetland and riparian areas in the project area. A vegetation inventory was <br />conducted on the riparian corridors of the Animas and La Plata and Mancos <br />Rivers and all vegetation within a one mile corridor was classified using <br />photo interpretation. An assessment of project impacts to riparian corridor <br />vegetation communities was conducted. <br /> <br />The results of the riparian impact studies conducted by Reclamation on the <br />Animas River predicts no impact to existing vegetation due to reduction in <br />groundwater levels, but it indicated there may be limited reduction in <br />cottonwood recruitment potential on low terraces between Flora Vista and the <br />San Juan River. On the la Plata River, impacts to existing vegetation from <br />reductions in ground water should be minimal (less than 10 acres). On the la <br />Plata River, between the La Plata Diversion Dam and the Southern Ute Diversion <br />Dam (SUDD) some impacts to the riparian forest may occur from erosion due to <br />the importation of sediment free water from Ridges Basin Reservoir. On the la <br />Plata River below the Southern Ute Diversion Dam, if flow management <br />strategies are implemented, no impacts to cottonwood recruitment is <br />anticipated. loss of cottonwood trees associated with irrigation canals could <br />occur when canals are abandoned due to project implementation. <br /> <br />The combination of pumping water (with suspended sediment) from the Animas <br />River that has high levels of selenium into Ridges Basin, where high levels of <br />selenium are present in some soils, could cause a potential contaminant <br />bioaccumulation problem in the food chain (Rick Krueger, USFWS, pers. comm.). <br /> <br />The reasonable and prudent alternative outlined above for Colorado squawfish <br />and razorback sucker allows for the construction and operation of Stage A <br />only. No impacts to riparian vegetation used by bald eagles on the Animas or <br />la Plata Rivers is anticipated for Stage A. However, there maybe some <br />bioaccumulation of contaminants in the prey base associated with Ridges Basin <br />Reservoir. Some impacts may occur to cottonwood recruitment in riparian areas <br />