migratory females helped explain how habitat affected home 

 range (Fig. 8.10). Polygon home range size for 3 resident 

 females was much smaller than that of 4 migratory deer. There 

 was no acceptable winter range adjacent to the spring-summer 

 ranges of the 4 migratory deer, and they moved 4-6 km to other 

 areas during autumn and winter. Three of the 4 migratory deer 

 used the same areas during winter and the other used a 

 different winter area (Fig. 8.10). Winter areas were less 

 than 1 km from the center of the PHR of resident females. 



We believe that "parturition territoriality" (Ozoga et 

 al . 1982a) and the limited availability of quality wintering 

 sites led to the establishment of the migratory movement 

 pattern. Because not all deer that used the area included in 

 Figure 8.10 were marked, total home range overlap could not be 

 mapped. It is likely, however, that territoriality during 

 parturition and the early post-partum period limited the 

 number of females that could establish residence near areas 

 suitable as winter range. As the population increased, 

 parturition territories were established at increasing 

 distances from high quality winter range. 



Females establishing fawn-rearing territories at some 

 distance from the winter range probably were fawns of females 

 resident to winter range areas. After fawn rearing 

 territories became less rigid during late summer and autumn, 

 the younger females may have regrouped with their mothers and 

 continued to use the same winter areas. As time passed and 

 the older females died, the younger females continued to use 

 separate summer and winter areas because of tradition and 

 necessity rather than because of social ties. During mild 

 winters, it was possible for deer to remain in the 

 spring-summer range of females A, C, D, and E (Fig. 8.10). 

 During winters with deep snow, however, it is unlikely that 

 many deer, especially fawns, remaining in those spring-summer 

 areas would survive. Over the long term, females that have 

 spring-summer home ranges in areas of low relief near the 

 prairie are unlikely to recruit many fawns (genes) or survive 

 themselves if they do not maintain a migratory tradition. 



The resident pattern is probably the natural pattern 

 because it is less costly in terms of energy expenditure and 

 exposure to hazards. However, when an area is near maximum 

 fill, at high population levels, a migratory movement pattern 

 must develop. Some deer establish a resident pattern in low 

 relief habitat, especially during long, mild weather cycles, 

 but they are those most likely to die during severe winters. 



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