2010-12-17_REVISION - C1981019 (163)

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0 at the new lek location, STLek3. All birds had left the lek by the time it was approached on foot at approximately 8:30 am. 3.2 Raptor Nests Ground surveys located a total of 77 possible raptor nests within the Collom wildlife study area. It was believed that ground surveys provided a relatively comprehensive survey of most potential nesting habitat except for the aspen stands in the southern one-third of the study area. The fact that aspen trees were leafed out during the June 2007 survey periods and vehicle access into the higher elevation aspen areas, prior to leaf-out, was prohibited by lingering snow drifts during the April 2007 survey, precluded adequate nest survey coverage of potential tree nest sites in aspen stands. A listing of all nests located with their UTM coordinates and activity status is provided in Table 2. Table 3 provides a summary of nests by species and activity status. Nest locations within the study area are plotted on Figures 2A and 2B. Nest identification numbers on Figures 2A and 2B correspond to the nest identification numbers in Table 2. As indicated on Figure 2, the majority of nest sites were located in rock outcrop areas and trees along the major drainages within the study area. Tree nest sites within the drainage bottoms were associated primarily with boxelders (Acer negundo). A few tree nests were also found in cottonwood trees. Golden eagle, red-tailed hawk, and Cooper's hawk were the only breeders located in the study area in 2007. Three 2006 breeding species, long-eared owl, great horned owl, and turkey vulture, were not found to breed in the survey area in 2007. Active golden eagle nests were down one (four to three) from 2006 to 2007 while active red-tailed hawk nests increased by one from one to two. Active Cooper's hawk nests remained at one from 2006 to 2007. Based on nest configuration and placement, it was assumed that prairie falcon and Swainson's hawk have also historically nested within the study area. 7