Females and fawns, again as expected, were significantly 

 positively associated; though the correlation coefficient did 

 not approach 1.00 because not all females produced or reared 

 fawns each year. The distribution of females was 

 significantly negatively correlated with the distribution of 

 mature males and was also negatively correlated with yearling 

 males, but not significantly. The negative correlation 

 between distributions of fawns and mature males was 

 significant as was that between fawns and yearling males. 

 Distributions of yearling and mature males also were 

 significantly negatively correlated with each other. 



The stronger negative correlation between fawns and 

 mature males than between females and mature males indicated 

 that mature, productive females with fawns generally were 

 distributed differently than mature males, whereas non- 

 productive females often occurred in the same 28.8-ha blocks 

 as males. The data also indicated that yearling males were 

 more widely distributed and occurred in the same blocks as 

 females more often than mature males . 



Temporal Changes in Spatial Distribution 



Comparison of Figure 7.1 with a more generalized map of 

 density distribution of mule deer on the study area during 

 1960-1964 (Fig. 7.2, Mackie 1970) indicated that areas of 

 highest and lowest densities were reversed for the 2 periods 

 of intensive study. This difference may have been influenced 

 by 2 major environmental changes. The first involved changes 

 in timing of livestock grazing. The area of comparatively 

 high mule deer density during 1960-1964 was centered around a 

 private ranch on which cattle were grazed only during winter. 

 In about 1970, the area was leased to other operators and 

 thereafter heavily grazed during spring and occasionally 

 grazed during other seasons. Winter grazing with supplemental 

 feeding probably had little effect on the composition and 

 abundance of spring and summer forage for deer and may have 

 made spring growth more available. The absence of livestock 

 in this diverse drainage-head habitat of moderate to low 

 topographic relief may also have rendered succulent, high- 

 quality forage more available through summer. Conversely, 

 heavy grazing during spring over several years may have 

 reduced the quantity and quality of summer forage and 

 decreased quality of the area as fawn-rearing habitat. 



Grazing practices along the northern and northwestern 

 portion of the area, which held relatively low deer densities 

 in the early 1960s and high densities in recent years, 

 followed the opposite trend. Headquarters ranches and winter 

 livestock grazing and feeding operations along the Missouri 

 River were phased out during the 1970s. There, habitats 

 adjacent to the river that had been moderately to heavily 



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