237 



census strip on the Prairie Dog Creek study area was located 

 right along the border of the Kirby area. It supported 27 

 species and approximately 155 pairs of songbirds per 100 ha 

 (Martin 1980a). 



The grassland census strip supported the fewest number of birds 

 Vesper sparrows made up 6l% of the birds observed. This strip 

 was located in the western portion of the study area on a high 

 ridge. Grassland and sagebrush habitat in the more xeric eastern 

 part of the study area was probably more similar in productivity 

 to the Birney sagebrush census strip (Table 133). 



Raptors 



Twelve species of hawks and two species of owls were found on the 

 studv area (Table 129). Nine of these were known or suspected 

 breeders. Fifteen nests, excluding American kestrels, were 

 found on or near the study area (Table 13^ and Figure 106). This 

 nest census is not considered complete. Red-tailed hawks, great- 

 horned owls, and American kestrels were the most common breeding 

 raptors . 



Nine species of raptors, excluding American kestrels, were observed 

 as migrants or wintering on the study area (Figure 107). The Tongue 

 River along the east boundary of the study area and the southwestern 

 corner of the study area received the highest use by non-breeding 

 raptors. 



The goshawk, Cooper:':s hawk, golden eagle, bald eagle, osprey, 

 orairie falcon, merlin, and saw-whet owl are listed by Flath (I98I) 

 as SDecies of special interest or concern in Montana. The golden 

 eagle, bald eagle, osprey, prairie falcon, and merlin are also 

 listed as species of high federal interest. The status of each 

 of these within the study area is as follows: 



Goshawk- One was observed on 27 August 198I. This bird was 

 probably a migrant, although the area in which it was observed 

 has dense stands of ponderosa pine which may be suitable 

 for nesting goshawks. They are known to nest in the Wolf 

 Mountains, approximately l4 miles to the southwest (Lockhart 

 1976). 



Cooper's hawk - Several observations of adults were made during 

 the breeding season in the northwestern corner of the study 

 area. They probably had a nest located nearby, but an intensive 

 nest search was not made. 



Golden eagle - One pair had part of their territory on the 

 western end of the study area. They probably had one or more 

 nests located somewhere west of the study area. They were 

 suspected not to have nested in 1981, because the pair was 

 often seen together in the Kirby area in spring when the 

 female should have been incubating eggs. Their nesting 

 status in 198O was unknown. There are many suitable nest 

 sites in the portion of their territory within the study 

 area, so this pair should be checked in the future if coal 

 development should take place. 



