Vegetation types (habitat categories) and topography types were recorded 

 for 89% of all mule deer sighting locations. Mule deer were observed feeding in 

 39% of sightings. A wide variety of habitats were used by mule deer yearlong 

 (figure 27, see also Appendix K). The most important habitats during eyery 

 season were grasslands and sagebrush habitats. Tall coulee shrub habitats 

 became more important during summer and fall, stubble fields were most heavily 

 utilized during the fall, and sagebrush habitats became most important during 

 winter. Little bluestem stands were important for a short period in early 

 spring. Figure 28 shows monthly changes in topography use by mule deer; it 

 can be seen that coulees, hills, and ridgetops were important yearlong. 



During the winter of 1975-1977, mule deer were observed most frequently 

 in silver sagebrush/grassland (22%) and badlands (17%) habitats (figure 27). 

 These two habitats also accounted for the majority of feeding observations. 

 Substantial numbers of mule deer were observed in silver sagebrush/grassland 

 habitats throughout this winter, while they first appeared in badlands during 

 February. Badlands probably provided shelter from winter winds and snow. Mule 

 deer were observed on a wide range of topographic features during this winter 

 (figure 28). Observations during December occurred largely on flat areas, 

 ridges, and rolling terrain. Coulees, hills, and ridges were more frequently 

 used during January and February. Mule deer were most often seen feeding on 

 hillsides, in coulees, on ridgetops, and on rolling terrain. 



In spring of 1977, mule deer use of grasslands (23%) and little bluestem 

 stands (18%) showed an increase (figure 27). Sagebrush habitats remained im- 

 portant, reflecting the general spring green-up of vegetation and dispersal of 

 deer; remaining observations were distributed among several habitats. Feeding 

 observations were mainly in grassland, little bluestem, and big sagebrush habitats 

 Topography use during the spring reflected habitat use, with the highest propor- 

 tion of all sightings (33%) and feeding observations occurring on rolling topo- 

 graphy (figure 28). A variety of topography accounted for the remaining spring 

 observations. 



During the summer of 1977, mule deer were most frequently observed on grass- 

 land (19%) and silver sagebrush/grassland (19%) habitats (figure 27). Tall cou- 

 lee shrub habitats, providing more shaded cover, accounted for 21% of the summer 

 observations. Use of grasslands appeared to decrease from June to August, while 

 the use of coulees increased, possibly in response to the desiccation of open 

 grasslands. Locations of feeding observations did not differ suostantially 

 from all observations combined. Topography of observation locations also ap- 

 peared to vary from June to August. Rolling topography, hillsides, and ridges 

 contributed 52% of the June observations, decreasing to 38% in July and 37% in 

 August (figure 28). At the same time, mule deer were observed more frequently 

 in coulees, which accounted for 20% of the observations during June, 36% during 

 July, and 47% during August. Topography at summer feeding observations did not 

 differ from these results. 



In the fall of 1977, grasslands (27%) and stubble fields (16%) provided 

 the most observations, with substantial use also occurring in big sage and 

 coulee shrub habitats (figure 27). A wide variety of vegetation types accounted 

 for the remaining observations. Mule deer were observed feeding primarily in 

 grasslands and stubble fields. Over 30% of mule deer observations occurred in 

 coulees each month during the fall. Rolling topography and hillsides were also 



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