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<br />to further negatively influence marsh development. Flow stages associated with flows less than
<br />powerplant capacity, 33,200 cfs occurred in the pre-interim flows period (1964-1989), a time
<br />period during which fluvial marshes proliferated in Grand Canyon. It is important to note that the
<br />extent of wetland habitat use by nesting southwestern willow flycatchers remains undocumented.
<br />This subspecies evolved along a river that was naturally highly flood-prone and supported little
<br />marsh habitat (Stevens et ai, 1995). Also, in post-dam time, E.!. extimus successfully occupied
<br />territories through a series of high inflow years (1983-1986) when marsh habitats were largely
<br />scoured from the river corridor (Brown 1988). Therefore, the impacts marshes associated with
<br />southwestern willow flycatcher nest sites may not have any detectable impact on this subspecies'
<br />foraging success or efficiency.
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<br />The proposed October, 1997, Test flow will have no affect on the endangered Southwestern
<br />willow flycatcher.
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<br />LITERATURE CITED
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<br />Kanab AmbennaiJ, Bald Eagle and Peregrine FalcoD
<br />
<br />Behle, W.H and HG. Higgins. 1959. The birds of Glen Canyon. Pp 101-133 in Woodbury,
<br />AM. (ed.). Ecological studies offlora and fauna in Glen Canyon. University of Utah
<br />Anthropological Papera 40 (Glen Canyon Series No.7).
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<br />
<br />Brown, B.T. 1991a. Abundance, distribution, and ecology of nesting peregrine falcons in Grand
<br />Canyon National Park, Arizona. Grand Canyon National Park Report.
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<br />
<br />Brown, B.T. 1993. Wmter foraging ecology of bald eagles in Arizona. Condor 95:132-138.
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<br />Brown, B.T., S.W. Carothers, L.T. Haight, RRJohnson, and MM. Riffey. 1984. Birds of the
<br />Grand Canyon region: an annotated checklist. Grand Canyon Natural History Association,
<br />Monograph Number 1. 54 pp.
<br />
<br />Brown, B. T. and W. C. Leibfried. 1990. The effects of fluctuating flows from Glen Canyon Dam
<br />on bald eagles and rainbow trout at Nankoweap Creek along the Colorado River, Arizona. 1990
<br />Interim Report to the Glen Canyon Environmental Studies, U.S, Bureau of Reclamation, Upper
<br />Colorado Region, Salt Lake City, UT.
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<br />
<br />Brown, B.T., R. Mesta, L.E. Stevens and J. Weisheit. 1989. Changes in winter distribution of
<br />bald eagles along the Colorado River in Grand Canyon, Arizona. Journal of Rapt or Research
<br />23:110-113.
<br />
<br />Brown, B. T. and L.E. Stevens. 1991. Influences of fluctuating flows from Glen Canyon Dam
<br />and, effects of human disturbance on wintering bald eagles along the Colorado River in Grand
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