polygons per block and steeper terrain than summer range 

 areas . 



Migratory deer generally moved from areas of low relief 

 at the heads of drainages along the southern edge of the area 

 to areas of steep terrain near the Missouri River. Thus, most 

 of the difference in habitat characteristics between seasonal 

 ranges was apparent without statistical tests. The 

 interpretive problem related more to separation of cause and 

 effect and elimination of possible spurious relationships. 



Steeper terrain containing adjacent north- and 

 south-facing slopes appeared to be the most important factor 

 distinguishing winter from summer ranges of migratory deer. 

 Differences in vegetation cover types and diversity followed 

 differences in terrain and thus did not appear to be the 

 primary determining factors in deer preference for those 

 areas. For example, the 2 eastern wintering areas lacked the 

 Douglas fir type, 5 of the 7 lacked the silver sagebrush type, 

 and 3 lacked the river riparian type. On the other hand, 

 steep terrain generally held lesser snow depths and provided 

 thermal environments more favorable to deer survival than 

 level or rolling terrain. North-facing slopes usually were 

 dominated by timbered types with dense overhead cover that 

 further reduced snow depth and provided thermal cover. 

 South-facing slopes generally were more open, providing for 

 rapid snow melt as well as warm areas for resting and foraging 

 on sunny days . 



Mule Deer Habitat Use in Relation to Elk and Cattle 



A prior publication (Mackie 1970) focused specifically on 

 habitat use relationships between mule deer, elk, and cattle 

 on the study area during 1960-1964. Although we do not 

 propose to review those relationships in detail, data obtained 

 from subsequent studies, especially during 1976-1984, enabled 

 us to re-examine previous conclusions based on additional 

 information and different analytical techniques. 



Data on numbers and general distribution of elk were 

 recorded during all aerial surveys in winter 1964-1975. 

 During 1976-1984, numbers and locations of all elk observed 

 during seasonal aerial surveys were recorded identically to 

 those for mule deer and were compiled and analyzed using block 

 analysis. Time and other considerations precluded us from 

 collecting quantitative data on cattle distribution or habitat 

 use after 1963. Thus, conclusions relating to mule 

 deer-cattle relationships can only be reviewed qualitatively 

 on the basis of general observations and additional studies 

 conducted on the supplementary NCRCA during 1972-1975 (Knowles 

 1975, Komberec 1976, Campbell and Knowles 1978) and during our 

 studies in 1976-1986. 



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