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002214 the Colorado River. An unconfirmed sigh~ing at the mouth of La Sal Creek was reported during 1994 season but no birds were found along the surveyed reaches of river. However, southwest willow flycatchers were located on the tributaries of Roc Creek and West Creek which enter the Dolores River below the confluence with the San Miguel River. , ~~e southwestern willow flycatcher is most frequently associated with riparian habitats along rivers, stre~~s,.or other wetlands, where dense growths of willows, seepwillow, arrowweed, buttonbush, or other native shrubs and medium- sized trees dominate-often with a scatteredoverstory of larger, mature cottonwoods (Federal Register, !995a;Tibbitts et al., 1994). Suitable habitat is limited in the surveyed sections of river. Willow communities are present throughout the Dolores drainage, but the co~~unities are limited in area and the specie which occ~rs is small in size. Implementation of the proposed action would not affect the existing riparian zone, and would therefor not affect this subspecies. COLORADO SQUAWFISH Of the four federallv protected fish species addressed in this assessment,' only the Colcradc squa~=ist has been his~o~ically reported from ~he Dolores River (Valde=, et a:., 1992). Eistorically, Colorado s~~awfish have bee~ repor~ed as fa= ~?s~ream as Pa=acox Valley as rece~~ly as 196~. Seve=al c~he~ colle=~ions c=.s~~awf~sh have been ~epo~~ec =ro~ ~ne Delores Rive~ in ~he :950'5 and 1960's. However, twO s~rveys conducted in the 1970's and ear~y ~980's of the Dolores River did not encounter this species (Valdez, et al., :952)_ P=io= ~o the cons~=ue~~on c= McPheE Dam, ex~reme seasonal tiewa~e=~ng cue to ~==~ga~ion c~ve=s~c~5 (?=~ma=~ly ~he Mon~e=uma Va::ey :==iga~io~ Company Divers~on nea= Dolores, cclo=atio) couplec ~i~~ poc= wa~e= ~~a~i~y condi~ions could have restricted ~he use c: ~he Dolores River by Colorado squaw=ish. O?e~a~ion of ~ cran~um ~~:: Fro=essi~; plan~ nea= the Sa~ M~que: R~ve= a~ V~ava~t Cclc=aac =~o~ ~he ~~c :;40'5 ~h=oug~ ~he ea=ly 1970.5 is kno~n ~c have =esul~ec i~ seve=al ~cxic sp~::s i~~c ~he~~ive=. Valdez, e~ a:.f ~992 also repor~ a c=a~iu~ c6ncen~=a~~~~ p:a~~ was cpera~ional nea~ SlicY~ock, Colorado over generally the same time =rame. Perhaps the most adverse limit:at:.ion to aquatic ----':ife i:-, t.he Dolo~es River may OCCU:" ~hrough Paradox Valley, Colorado, where water quali~y is severely degraded by the natural inflow of brine groundwater. During low flow conditions, the concen~ra~io~ 0: sal~ i~ ~he =iver ca~ e~ceec th~ee ~imes ~he concentratic~ c: sea water ....irtually eliminatinc; all aqua~ic :..ife downstream to the confluence of the San Miguel Rive~. A :ishe=y 5~udy ccnduc~ed by EIO/WEST Inc. in 1991- 92, encompassed the sec~ion of the Dolores River frornBradiield Bridge (about ~welve miles downstre~~ of McPhee D~~) to the confluence of ~he Colorado River (Valdez, et al., 1992). During the course 0: this study, four Colorado souawfish were captured from the Dolores River, all within.2 kilometers of the Colorado River. It is not known if ~hese :ish were temporarily using the Dolores River or were permanent residents; however, since all of ~he squawfish cc:lec~ec were i~ 5uc~ c~ose p=cxi~~~: to the Cclcradc River, it is p~obable ~:-;e~~ we=e only t:.e~pcr=.=':":'Y in~ab.:.~.:.::; ~he ~c:'c::"es F~.:..ve=. Cc:o=ad~ s~ua~=~E~ a=e kno~~ ~~ o=c~= ~~ the Ccloradc ~~ve= Cow~5~=earr; c= ~~~ -- ... D' - . ccn:~ue~ce \o..'~-=,:: ':.:1.e ' :::::...:..c=eE .........:.\:re=-: :-. ::>-""'eve= / ~he 5~c:: ~ag~~~~~E i~ =lo~ c~G~~C :c