198 



and DuBols (1979) all point out the importance of deciduous tree and 

 shrub cover to songbirds. The presence or absence of water year- 

 round mainly affects the songbird community indirectly by affecting 

 the quantity and quality of deciduous tree and shrub (riparian) 

 vegetation. 



Raptors 



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

 study area. Nine of these were known or suspected breeders. 

 Thirteen nests, excluding the American kestrel, were located in or 

 near the study area (Table 108 and Figure 92). This nest census 

 is not considered complete. In addition, a turkey vulture roosting 

 area was identified (Figure 92). About 15-20 turkey vultures 

 used this roost throughout both summers. Red-tailed hawks, great- 

 horned owls, and American kestrels were the most common breeding 

 raptors. 



Ten species of raptors were observed migrating or wintering on the 

 study area. Observations of all except the American kestrel are 

 shown in Figure 93. Two areas of high use by wintering bald 

 eagles are delineated. The distribution of wintering bald eagles 

 probably depends on the location of open water "holes" while the 

 river is frozen. Bald eagles were observed eating fish next to 

 these "holes" during the short period in January and February 1981 

 when the Tongue River was frozen. Livestock loss also provides 

 food along river bottoms for wintering eagles. 



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

 prairie falcon, and merlin are listed as species of special interest 

 or concern by Flath (198I). The golden eagle, bald eagle, osprey, 

 nrairie 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 2 June 198O, which is within 

 the normal nesting period for this species. One sighting does 

 not constitute good evidence for breeding; however, several 

 unidentified accipiters (observed from too far for this 

 observer to correctly Judge size and color) may have been 

 goshawks, and some suitable habitat for nesting goshawks is 

 present in the study area. 



Cooper's hawk - One migrant was observed. This species may also 

 be present as a breeder (see explanation under goshawk). 

 Accipiters tend to nest in heavily timbered areas where they are 

 easily overlooked in general wildlife surveys. 



Golden eagle - This species is listed as a visitor. Several 

 pairs of eagles appeared to have territories to the north, east, 

 and southeast of the study area, but were rarely observed on 

 the study area. Although these birds were mapped as "breeding" 

 eagles on the breeding raptors map, the study area does not 



