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OU2212 H. DOLORES RIVER BASIN BALD EAGLE Bald eagles overwinter in the area and regularly use that reach of the Dolores River just downstream from the dam. Since the closure of the dam, as many as thirty of these federally-protected raptors nave been reported' from this portion of the Dolores River during the winter (pers. comm.Mike Zgainer, CDOW, 1993). Strongly associated with riparian areas and open water, bald eagles are attracted by an accessible food source, consisting primarily of waterfowl and fish.- Over the last three years, the availability 0: open water associated with a 30 cts winter time flow is restricted to the firs~ 1-2 rr.iles downstream of the dam. Water released during the winter has been averaging near 380 F. From 1984 through 1989, wintertime flows through the darn were never reduced below 78 cfs, as prescribed under McPhee Dam's original operating criteria. It is expec~ed higher winter releases would result in more of the river remaining ice tree; however, flows other than- 30 cfs have not been monitered. Further dewns~ream, the river more frequently ices ever, as does much of McPhee Reservoir. Because of lL~ited open water in recent years, waterfowl tend to concentrate in the tailwater area below the dam. These waterfowl may well cens~itute the primary food source of bald eagles win~ering along this reach of the "Dolores. . Also, as has been documen~ed i~ numerous other repor~s, Recl~,ation assumes carrion, primarily elk and deer, ~lso are par~ c~ the bald eagles win~er ciie~. The availab~lity o~ a concen~rated and reliable food source, along with closure to public access cf ~he road parallel~ng the =i:s~ ~ miles of ~he ~iver below ~he dam, co~~ine tc p=ovicie an attrac~ive wi~~erin~ si~e =0= balci eagles. The nearest ~'own nest in; pairs cf bald eagles have been re?cr~e= ~~ ~~e ~os~ Canyon area (lG-2C rr.i:es :row ~~e darn) and west of Ccrte= (pers. comc.,. :erry Craig, CDOW, 1993). Neither of these twc nes~in; pa~rs are aepender.~ cn ~~e Dolores R~ve~ downs~ream ==om McPhee ~alli, a~~hocgh ~he ava~lable c: s~~~able nes~ing habita~ i~ the dra~nage coulc reswlt in su~~er cse c: -~~~s po=~ic~ c: the Delores a~ some time in the f~~ure (pers. co~m. Jerry Craig, CDO~, :9=3). Over the long term, .implementation 0: the proposed action would :'ikely bene::i~ wintering bald eagles. The proposed action woclci avoid re~u=~ing ~c the extreme, chronic low flow (20 cfs) years (no action alternative), which would reduce the exten~ of open water downs~ream 0:: McPhee Dam during the winter. Since downstream fish communities would benefit from pool management, a valuable eagle prey base would remain available. ~he proposed action may increase the potential incidence and extent of river icing during-the winter due to maintenance of lower base flows during "normal" (SO cfs) and "we~" (78 cfs) years than would occur under thenn action alternative. Reclamation has no data relating the winter time use of the Dolores River by bald eagles at flow higher than 30 cfs. While rr.ore of the river may be open at higher flow, Reclamation cannot project how m~ny more bale eagles, if any, the river might support under these conei~ions. In ~he absence of data ~c the contrary Reclamation; therefore, believes the proposed actic~ wo~lc nc~ adversely affe~t wintering bale eagles downstream of ~=Phee Da~. E;