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type was that these areas have a poorly developed riparian habitat. Hoffmann 

 and Pattle (1968) stated that sunken can traps would probably turn up many 

 specimens of this hitherto "rare" shrew and, indeed, the specimen was captured 

 in a pitfall trap. In all probability , this "special interest or concern" 

 species would have been missed if pitfall traps were not employed. 



Big Brown B at {Eptesicus fesous) - Ten specimens of the big brown bat were 

 collected on the area and many more were observed. Collection of these specimens 

 occurred at widely separated sites and indicated this species was common on the 

 area. Breeding colonies were located at two sites and more sites undoubtedly 

 existed. Sandstone outcrops and caves were utilized for breeding and roosting; 

 while stock reservoirs were used for feeding sites. 



Small-Footed Bat {Myotis leibii) - Only one specimen of the small-footed bat 

 was captured on the study area, therefore, it was listed as rare. This specimen 

 was captured in a mist net placed at an artesian stock tank in the sage-grassland 

 type. Swenson (1970) reported several specimens of this species were taken 

 in Miles City, Montana and one was captured in Glendive, Montanaa. The present 

 study area was between these two localities and this specimen serves to further 

 define the range of this species in Montana. 



White-Tailed Jackrabbit (Lepus toWnsendi) - This species occurred most frequently 

 in the sage-grassland type. The numerous observations of this species which 

 were obtained at night and while walking the area during daylight hours justified 

 listing it as common for the area. Local landowners stated that in peak population 

 years this species becomes abundant on the area. Coyotes, golden eagles and red- 

 tailed hawks were observed utilizing this species as prey and other predatory 

 species undoubtedly do likewise. 



Desert Cottontail (Sylvilagus auduboni) - Thirteen desert cottontails were 

 collected on the area and many more were observed. They were most often found 

 in the badlands and sage-grassland coulees. This species was listed as common 

 for the area and was known to be an important food source for the predatory 

 mammals and birds occurring here. 



Several cottontails were observed adjacent to the Yellowstone River bottomland 

 which resembled the mountain cottontail (S. nuttalli) but no specimens were 

 collected and the identification could not be verified. The study area lies 

 within the range of this species (Hoffmann and Pattie, 1968) and they stated 

 that in eastern Montana where desert and mountain cottontails are S3mipatric, the 

 latter is restricted to riparian shrubs along streams and river banks. Also, 

 presence of the mountain cottontail was documented considerably east of the 

 present study area (Matthews, 1979). 



Porcupin e {Erethizon dorsatum) - Evidence of porcupines on the area was obtained 

 from one direct observation in the sage-grassland and indirect observations (gnaw 

 marks on trees, tracks) in the limber and ponderosa pine badlands. Nowhere was 

 sign abundant and this, in conjunction with the lack of direct observations and 

 limited extent of pine habitats, justified listing this species as uncommon. 



Beaver (.Castor canadensis) - This furbearer was found exclusively in the creek 

 type at one large reservoir, and only in small numbers. It was therefore listed 

 as uncommon for this area. Damage to the scattered cottonwoods occurring on 

 the area and the damming of irrigation channels often results in destruction of 

 individuals by the local landowners. 



