SUMMARY OF WILDLIFE COMMUNITIES BY HABITAT CATEGORY 



In this section, a brief summary of wildlife communities inhabiting the 

 various habitat categories is presented, including a list of characteristic 

 species for each category. Primary habitat indicator species, denoted by an 

 asterisk following the name of the species, are those which are either restricted 

 to or attain greatest densities in a single habitat category. In general, bird 

 and mammal communities were found to be very similar to those reported for cor- 

 responding habitats in Dawson County, Montana (Swenson 1978), western North 

 Dakota (Stewart 1975, Stewart and Kantrud 1972), Petroleum County, central Mon- 

 tana (Best 1970, 1972, Cada 1968, Feist 1968, Tschache 1970, Walcheck 1970), 

 Fergus County, central Montana (Trout 1978), southern Alberta (Owens and Myres 

 1973), and Richland County, eastern Montana (Randall 1975). Certain habitat 

 categories of limited extent were combined with similar, more predominant types 

 where wildlife communities were similar. 



Riparian Cottonwood Forest (including riparian shrubbery and box elder-green ash 

 forest). 



River floodplain forests were the most structurally diverse of all habitats 

 studied and consequently supported the greatest faunal diversity. No census plots 

 or traplines were located in this forest, and it was only sampled by six stops -- 

 all on the Missouri River route--of the 250 roadside survey stops and by occas- 

 ional spot-checking. Nevertheless, this habitat was found to support more species 

 of breeding and wintering birds than any other habitat. This is consistent with 

 the findings of other studies that bird species diversity is closely related to 

 foliage height diversity and vertical layering of vegetation (MacArthur and 

 MacArthur 1971, Karr and Roth 1971, Roth 1976, Wilson 1974), both of which were 

 by far the highest in this habitat. The dense understory provided excellent 

 cover for ring-necked pheasants and white-tailed deer, both of which attained 

 greatest densities in this habitat. Characteristic species include: 



Yearlong Residents : ring-necked pheasant*, great horned owl, hairy wood- 

 pecker, black-billed magpie*, black-capped chickadee*, raccoon, white-tailed deer*. 



Winter Residents : bald eagle, Bohemian waxwing, tree sparrow. 



Summer Residents : red-tailed hawk, American kestrel, mourning dove, black- 

 billed cuckoo*, common flicker*, red-headed woodpecker*, eastern kingbird, western 

 kingbird, least flycatcher*, western wood peewee*, common crow*, house wren*, gray 

 catbird*, American robin, warbling vireo*, yellow warbler, orchard oriole*, north- 

 ern oriole*, rufous-sided towhee, and song sparrow*. Wildlife communities of 

 riparian shrubbery (which is found within and adjacent to riparian Cottonwood 

 forest) and box elder-green ash forests were similar to those of the riparian 

 Cottonwood forest. 



Farm Groves and Cottonwood Groves 



These isolated stands of trees lacked the well -developed shrubby understory 

 of the riparian cottonwood forest and were usually more open and smaller than 

 5 ha (12 acres). Hence, they did not support the high diversity of wildlife 

 characteristic of their riparian counterparts. However, in many upland grass- 

 land or agricultural areas, these scattered groves provide the greatest local 



186 



