habitat that was not structurally different or obviously less 

 secure than that from which they had dispersed. For those 

 males that lived to 2 years of age, there was no apparent 

 difference in known age at death between those remaining in 

 the population (X = 3.6, n=12) and those that left the area (X = 

 3.5, n=5) . 



Based on population estimates, emigration and immigration 

 for yearling males apparently balanced during most years, so 

 dispersal did not contribute additional mortality to the 

 population. 



Effect of Home Range Location 

 on Mortality and Productivity of Females 



Because of indications that deer inhabiting parts of the 

 study area with low topographic relief experienced greater 

 mortality during winter than deer on other parts of the area, 

 we examined the relationships between home range location and 

 mortality and productivity of marked females. Home range and 

 movements data (see Chapter 8) indicated 2 basic movement 

 patterns for females: resident and migratory. Migratory deer 

 most often occupied areas of low topographic relief during 

 summer and moved at least 3 km to areas containing steeper 

 terrain during autumn or winter. Some resident deer inhabited 

 areas with low topographic relief yearlong, but most had home 

 ranges that included at least some steep terrain comprised of 

 north- and south-facing slopes. For analysis, low relief 

 terrain was defined as those areas occupied during summer by 

 marked migratory deer and all areas of equal or lesser relief. 



Mortality rates of marked females were examined during 3 

 winters of relatively high mortality (1981-82, 1983-84, and 

 1984-85). Data from prior winters were not included because 

 few deer were resident to areas of low relief during 

 population lows, and few of those were marked. Mortality 

 rates were compared among 3 movement and home range 

 categories: resident yearlong in areas with low topographic 

 relief; occupying areas of low relief during summer but 

 migrating to areas of steep terrain during autumn or winter; 

 and resident yearlong in areas that contained some steep 

 north- and south-facing slopes. 



Of 69 marked adult females that entered winter 1981-82, 

 9 (13%) died or disappeared and never were reobserved. In 

 1983-84, 12 (18%) of 67 marked adult females died, and in 

 winter 1984-85, 6 (13%) of 47 marked females died. For the 3 

 winters combined, 27 deaths occurred (15%) over 183 marked 

 adult female-winters. 



Mortality rates were significantly different among the 3 

 categories of home range use (X 2 =16.1, P<0.01, 2 df). 



167 



