Some deer moved to new areas of use during autumn and 

 remained near there during winter (Fig. 8.7). We believe that 

 movements of autumn migrants may have been at least partially 

 influenced by cattle grazing. The areas of low relief and 

 more open cover types that those deer moved from were 

 generally intensively used by cattle. The areas they moved 

 to, while providing steep south-facing slopes and thermal 

 cover on timbered north-facing slopes during winter, also 

 provided advantages during autumn. The steeper terrain was 

 less grazed by cattle and forage remained succulent longer on 

 the more extensive north-facing slopes. As a special case, 

 the autumn and winter ranges of females A, C, D, and E (Fig. 

 8.10), were within a "blind pocket" in the fencing system and 

 received exceptionally light use by cattle. Coincidentally, 

 the area they used during spring-summer may have been improved 

 as spring range because of heavy use by cattle during summer 

 and autumn. The lack of litter in those areas made early 

 spring growth of grasses and forbs more available to deer. 



Discussion 



We identified 2 general types of movement patterns for 

 adult females; resident and migratory. Within that framework, 

 however, home range size and movement patterns were extremely 

 variable, not only among deer and among seasons and years, but 

 for the same deer among seasons and years. Much of this 

 variation reflected seasonal and annual adaptation to 

 fluctuations in environmental conditions. The form of these 

 adaptations or adjustments depended upon the topographic, 

 climatic, vegetational and land use characteristics of 

 individual home ranges. Males generally had larger home 

 ranges than females. Home range during summer was smaller for 

 females with fawns than for those without fawns. Home range 

 size of adult females was not affected by deer density or 

 forage abundance, but summer home range size for fawns and 

 thus parturition territory of adult females was smaller at 

 higher densities. 



A home range develops as the result of tradition and 

 cumulative movements to satisfy daily requirements. Any 

 successful home range strategy must result in procurement of 

 enough quality forage, warm microsites during winter, escape 

 terrain from predators, hiding and thermal cover, and other 

 amenities to enable the deer to survive and successfully 

 recruit young. Generally, the smallest area to supply all 

 those amenities should be the most efficient home range size. 



Initially, the matrilineal social structure of mule deer 

 in this area provides the basis for home range formation by 

 females. The mother aggressively breaks the social bond with 

 her yearling daughter just prior to the birth of her new 

 fawn(s). During most years, few yearling females disperse 



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