n 



> 

 >_ 



CD 

 CO 

 -Q 



O 



0.5-, 



0.4- 



I Expected 

 ^ Summer 

 H Autumn 

 □ Winter 

 Ei3 Spring 

 Entire Year 



0-6 



7-13 14-20 



Topoindex Value 



21-28 



Figure 9 . 5 



Annual and seasonal distribution of mule deer 

 in relation to the degree of topographic 

 relief. Increasing topoindex = increasing 

 topographic relief (see text). 



We re-examined the possible influence of free water on 

 distribution and habitat use of mule deer on the area through 

 the block analysis of data for 1976-1984. There were 63 known 

 water sources on the area during that period as compared to 56 

 during 1960-1964. Of the 63, 44% were located in open 

 sagebrush-grassland or broad coulee bottom habitat, 38% were 

 on the edge of sagebrush and timbered vegetation types, and 

 only 18% were within timbered types. Because of this, the 

 visibility bias described earlier against observations of deer 

 in timbered types from vehicle routes would also be expected 

 to indicate greater than actual proportions of deer use close 

 to water sources . 



Analysis of deer dispersion during the wet summers of 

 1978 and 1979 showed that 43.9% occurred within 0.805 km of a 

 water source and 89.9% were within 1.61 km. During autumn, 

 those percentages were 41.4% and 88.4%, respectively. During 

 the dry summers of 1980 and 1983, only 20.0% of the deer 

 observed were within 0.805 km of a known water source, while 

 66.1% were within 1.61 km. During the subsequent autumn, those 

 percentages increased to 30.6% and 73.9%, respectively. 



254 



