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Red-Tailed Hawk (Buteo jamaioens-ts) - Red-tailed hawks were most frequently 

 observed in the creek type where numerous nests were found in the scattered 

 cottonwoods. A total of eight and thirteen active nests were located on and 

 adjacent to the study area in 1979 and 1980, respectively. All nests were 

 located in cottonwoods and were very visible in the spring and fall but difficult 

 to spot during summer. Most active nests had one to three inactive (i.e. old) 

 nests in the Immediate vicinity. Red-tailed hawks were known to evict a pair 

 of great horned owls which occupied an old red-tail nest. One red-tailed hawk 

 nest which had been active was abandoned when seismographic surveys and associated 

 disturbances occurred in the vicinity. Hunting by adults usually occurred in 

 the surrounding badlands and sage-grassland types. Red-tailed hawks are one of 

 the most common raptor species found on the area in summer months. Migrations 

 from and through the area took place in October. As red-tailed hawks left the 

 area, a corresponding increase in rough-legged hawks was noted. Historically 

 red-tails were common on this area (Cameron 1907). 



Swa Inson ' s Haw k {Buteo swainsoni) - The only Swainson's hawk observation on 

 the study area took place during the spring migration of 1979. No evidence of 

 breeding was observed on the area although potential for breeding does exist. 

 The lack of sightings was the basis for listing this "special interest or con- 

 cern" species as rare for the area. Paucity of Swainson's hawks is possibly 

 related to habitat factors which better serve the needs of red-tailed hawks. 

 Historically this species was common in this area and Cameron (1907) described 

 a migration of several thousand Swainson's hawks through this part of Montana. 



Rough-Legged Hawk (Buteo lagopus) - All observations of rough-legged hawks 

 occurred during fall and winter. A reduction in the numbers of red-tailed 

 hawks with fall migration corresponded with an increase in the numbers of rough- 

 legged hawks observed. This species was obsei-ved using the sage-grassland type 

 for foraging and was often seen perched on fence posts and telephone poles in 

 this type. Because the records of this species are wintering records, and even 

 then not in great numbers, it was listed as uncommon for this area. The effect 

 on this species of a more severe winter could not be ascertained. Historically 

 it was a common winter resident but became very scarce when traps and poison 

 were put out for wolves (Cameron 1907). 



Ferruginous Hawk (Buteo vegalis) - The majority of the sightings of this species 

 occurred during spring migration. The only active nest of this species on the 

 area was located on a scoria butte on the edge of the badlands. Adults from 

 this nest were observed hunting on the adjacent grassland vegetation type. Be- 

 cause only one active nest was located, and sightings during migration were not 

 common, this "special interest or concern" species was listed as rare for this 

 area. Cameron (1907) listed this species as "a resident but never common." 



Golden Eagle (AquiZa ohrysaetos) - Three active nests of this species were 

 located in 1979. Two active and two occupied (but inactive) nests were located 

 in 1980. In addition, golden eagles were frequently observed in the sage-grassland 

 type, particularly around prairie dog towns, and are known to winter on this 

 area. Because of these factors this "special interest or concern" species was 

 listed as common for this area. Cameron (1907) stated this species was formerly 

 very common but that it had been almost exterminated by traps and poisons set 

 out for wolves. 



