period of population increase from 1976 to 1983. Average 

 adult female density across the study area increased from 

 1.08/km 2 during 1976-1978 to 2.66/km 2 during 1981-1983. At low 

 densities, the contiguous blocks occupied by females (Fig. 

 7.3) were equivalent to the major "core areas" (Fig. 7.1). A 

 few individual females who's distribution was not plotted in 

 Figure 7.3 occurred in scattered, isolated blocks. Relative 

 density distributions of females at low and high densities 

 (Table 7.4) indicated that densities in the "core blocks", 

 occupied throughout the period, did not increase as total 

 number of deer increased. Instead, there was increased 

 occupancy of blocks immediately adjacent to "core" blocks and 

 in areas that were unoccupied during the population low. 

 Blocks immediately adjacent to "core blocks" ultimately filled 

 to about the same relative density as the "core". Thus, 

 neither increases nor decreases in total deer numbers occurred 

 equally across the area. Populations in "core blocks" 

 remained relatively stable, while most of the changes occurred 

 in adjacent areas. During population increases, blocks 

 adjacent to "core blocks" were occupied by yearlings recruited 

 from the "core blocks". Occupancy of more distant, previously 

 unoccupied habitat may result from presaturation dispersal of 

 yearling females from "core areas" (Lidicker 1978). 



We do not imply that numbers of deer within broad "core 

 areas" did not increase with population size. Most yearling 

 females used the same general home range area as their 

 mothers. Thus, absolute density within the broad "core" 

 increased with population size. However, density in small 

 "core blocks" did not increase because mother and daughter did 

 not use the same sites at the same time during summer and 

 early autumn, and the younger females increasingly used blocks 

 immediately adjacent to those used most intensively by 

 established matriarchs. 



Social Organization and Distribution 



Little information has been published on the social 

 organization of mule deer. Geist (1981) discussed the 

 behavior, but not specifically the social organization of 

 Rocky Mountain mule deer (O. h. hemionus) . He stated (Geist 

 1981): "Unfortunately, there is no study to indicate whether 

 black-tailed deer and mule deer normally live in groups that 

 are closely related genetically." Most existing information 

 on social organization (Dasmann and Taber 1956, Miller 1970, 

 and Miller 1974) relates to Columbian black-tailed deer (O. h. 

 columbianus) . Considerably more detailed information is 

 available on the social organization of white-tailed deer 

 (Hawkins and Klimstra 1970, Hirth 1977, Nelson and Mech 1981, 

 and Ozoga et al. 1982a). 



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