"Summer forage should allow adequate milk production by does 

 and permit all deer to achieve adequate growth and fat 

 storage. Autumn forage should be abundant and of good quality 

 to delay the depletion of fat stores. Winter range should 

 provide forage that minimizes energy deficits and fat 

 depletion. Spring range should offer feed that permits early 

 recovery from stresses of winter." 



We view the first essential of mule deer habitat as 

 space, a place to exist. Although this may seem basic or 

 trite, it is important to establish that houses, highways, 

 airports, parking lots, mines, other animals, etc. usurp space 

 for living. Similarly, deep, drifted snow reduces space for 

 living. Thus, not all space is usable throughout the year. 



What types of space best provide for the requirements of 

 mule deer? We found that mule deer were positively associated 

 with topographic and vegetational diversity. Across their 

 species distribution, mule deer occur in a wide variety of 

 habitats and vegetation complexes. This is true even within 

 Montana. Generally, however, relatively steep, broken terrain 

 on at least a portion of the area is a common feature of all 

 mule deer habitat. 



Gentle terrain was uninhabitable by deer during severe 

 winters on our study area. Rough terrain provided south- 

 facing slopes that were relatively snow free and timbered 

 north-facing slopes that provided thermal cover and uncrusted, 

 undrifted snow cover of lesser depth than on open areas. 

 Rough terrain also helped provide vegetational diversity and 

 microclimatalogical diversity which provided forage diversity 

 and extended the period of availability of succulent forage 

 during late summer and autumn. Habitat diversity also 

 interacted with the social system of mule deer to provide more 

 parturition territories in more diverse areas. Rough terrain 

 and thick timber limited hunter access, thereby increasing 

 security for deer. It also provided mule deer better hiding 

 and escape cover from coyotes by limiting the ability of 

 coyotes to maintain visual contact with the deer. Overall, 

 physiographic and vegetational diversity provided the best 

 natural system to provide quality forage for the longest 

 periods. It also provided more alternative use areas to 

 compensate for the variety of environmental and man-induced 

 events that occurred. 



Often ecological reports spend many pages discussing 

 animal use of and importance of specific habitat-land types. 

 We will not do that here. Rather, to understand and affect 

 mule deer population dynamics, we believe it more important to 

 understand why mule deer used some types more than others and 

 some at different times than others. As noted previously, 

 mule deer live in a variety of environments, thus the specific 



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