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mammalian prey during fall and winter months (Wickersham, 2016, p. 172). Contrastingly, <br /> Golden Eagles prefer nesting on cliff bands and 75% of their diet consists of small mammals <br /> including hares, prairie dogs, and other rodents (Wickersham, 2016, p. 168). Since the proposed <br /> action is located in upland habitat, relatively far from forested areas and cliffs, it is expected that <br /> this proposed action will not have a direct effect on eagle populations, but it is likely to have an <br /> indirect effect on habitat that supports its prey. <br /> Brewer's Sparrow <br /> The Brewer's Sparrow is a sagebrush obligate species that use sagebrush for their summer and <br /> breeding grounds. The Brewer's Sparrow often occupies tall, dense sagebrush stands that tend to <br /> grow in deeper soils. The Brewer's sparrow has seen significant decline in recent years, likely as <br /> a result of degrading and fragmented sagebrush habitat. Direct habitat loss, encroachment of <br /> pinyon juniper and spread of non-native forb and grass species likely pose the greatest threat to <br /> the Brewer's Sparrow. The BLM considers the Brewer's Sparrow as a sensitive species, CPW <br /> identifies the sparrow as a Tier 2 Species of Greatest Conservation Need, and the USFWS <br /> identifies it as a Bird of Management Concern (Wickersham, 2016, pp. 502-503). <br /> Burrowing Owl <br /> Burrowing Owls often nest in already created burrows and prefer prairie dogs, ground squirrels <br /> and other rodent burrows. Burrowing Owls will abandon nests if there is a lack of prey, such as <br /> from plague die-offs or increase in vegetation heights more than ankle tall surrounding the <br /> burrows. Burrowing Owls are often seen in grasslands and some are found in shrublands. Their <br /> diets are made up of insects, small rodents and occasionally small song birds (Wickersham, <br /> 2016, p. 260). <br /> Ferruginous & Swainson's Hawk <br /> Ferruginous and Swainson's hawks often nest in trees in shrub, grass or croplands, although <br /> Ferruginous Hawks will occasionally use cliff bands for nesting. Both hawks consume a variety <br /> of small rodents, but the Swainson's Hawk switches to a diet of grasshoppers in late summer. <br /> The reliance of Ferruginous Hawk's on prairie dog populations in winter and breeding months <br /> has been well documented and is particularly impacted by human presence or anthropogenic <br /> landscapes (Wickersham, 2016. pp. 182-186). <br /> Peregrine & Prairie Falcon <br /> Both the Peregrine and Prairie Falcons nest on cliff bands with Peregrine Falcons preferring tall <br /> cliffs and likely have large ranges. Peregrine populations were effected by DDT, but since the <br /> ban on DDT, the falcon populations have since rebounded. Sabotage and illegal hunting has been <br /> documented to drastically impact the prairie falcon population, although this threat is likely <br /> declining (Wickersham, 2016, pp. 310-313). <br /> Sage Thrasher <br /> The Sage Thrasher migrates to Colorado's shrublands during the breeding and summer season, <br /> and prefers large expanses of contiguous sagebrush. The Sage Thrasher will build nests at the <br /> base of dense clumps of sagebrush or other western shrub species. The Sage Thrasher population <br /> is increasingly threaten by loss, degradation, and fragmentation of sagebrush habitat, and is most <br /> DOI-BLM-CO-N020-2017-0003 29 <br />