more fawns and productive females occurred in blocks of 

 moderate to moderately-steep relief. Conversely, areas of low 

 relief received disproportionately heavy use by males . 

 Productive females and their fawns may have avoided extremely 

 steep terrain because summer-autumn forage and hiding cover 

 were lacking. Most of those areas had very sparse understory 

 vegetation, were dominated by bare shale soil, and thus were 

 poor fawn-rearing habitat. 



Distance to Free Water 



Because of the demands of lactation on adult females, we 

 believed that fawns and productive females might be more 

 closely associated with water sources than other deer, 

 especially mature males, and that differences would be most 

 evident during the driest summer and autumn periods . There 

 were significant differences in distribution between fawns and 

 mature males during dry summers (X 2 = 20.3, 3 df, P < 0.005) 

 and dry autumns (X 2 = 15.93, 3 df, P < 0.005). However, while 

 proportionately more fawns and productive females than mature 

 males were observed within 0.805 km of water source, 

 proportionately more fawns than adult males were also found in 

 blocks more than 2.41 km away. This indicated that the 

 distributional differences probably were not related to a 

 requirement for lactating females and fawns to range closer to 

 water than adult males. Other factors influencing 

 distribution and habitat use apparently were overriding. 



Relationship Between Mule Deer Density 

 and Habitat Selection 



Because mule deer were generally dispersed over more of 

 the study area during periods of high as compared with low 

 populations, it was possible that deer increasingly used less 

 favorable sites with regard to vegetation cover types, habitat 

 diversity, and topography as deer density increased. To test 

 that hypothesis, we compared deer use of and selection for 

 vegetation types, number of different cover types and cover 

 polygons, and TOPOINDEX categories during summer-autumn 

 between 1976-1978 and 1981-1983. Deer densities were lowest 

 in 1976 and generally low through 1978; they were high during 

 1981-1983, with the peak in 1983. 



There were no differences in deer distribution by cover 

 type between the 2 periods (X 2 = 23.4, 20 df, P = 0.27). 

 Thus, it appeared that most of the increase in deer numbers 

 occurred in blocks that were vegetationally similar to the 

 "core" blocks used during the population low, and little 

 increased use of less preferred habitat occurred. It is 

 possible that much preferred habitat became vacant during the 

 population decline of 1972-1976, and subsequent increases were 

 restricted largely to those areas. 



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