hunting mortality of males is likely to be compensatory, at 

 least some increase in survival of males should occur 

 following a reduction in harvest rate. 



Emigration and Immigration 



Relatively high rates of emigration (>50%) occurred among 

 yearling males during all years. Because our data did not 

 indicate annual declines in male populations owing to 

 emigration, yearling males from adjacent areas must have 

 immigrated to the study area in nearly equal numbers to 

 emigrants. Dispersal of yearling males can, thus, be viewed 

 as a mechanism for redistribution of males for genetic 

 interchange and allocating resources by sex, but not as a 

 factor that increases or decreases numbers of yearling males 

 within our study area. 



Emigration of yearling females was much more variable and 

 apparently not balanced by immigration. The majority occurred 

 at low population densities, among yearlings in the first 2 

 numerically large cohorts recruited following the population 

 low in the mid 1970s (those born in 1979 and 1980). Neither 

 emigration nor immigration were detected among marked deer or 

 in population estimates and classifications during years of 

 mid to high population densities (among cohorts born between 

 1981 and 1985). A probable temporary movement of adults and 

 fawns onto the study area from surrounding prairie during the 

 dry autumn of 1983 was not considered equivalent to permanent 

 immigration or dispersal of yearlings. A few females and 

 their fawns were also observed to temporarily move off the 

 area for a few weeks during some years . 



Net emigration apparently also occurred among yearling 

 females born in 1986. One of the 2 radio-collared yearlings 

 on the area in spring 1987 was known to have dispersed to the 

 north off the area; the fate of the other was unknown, but 

 radio contact was lost during the period when dispersal 

 occurs. Although this sample was too small to indicate the 

 degree of dispersal during spring 1987, it did indicate that 

 emigration occurred. Subsequent population estimates not only 

 documented that emigration of yearling females had occurred, 

 but also that it was extensive and involved up to 49% of all 

 females surviving from the 1986 cohort. Overall, about 215 

 females "disappeared" between spring 1987 and December 1987. 

 About 100 of these could be accounted for as hunting 

 mortalities during autumn 1987, most of the remaining 115 had 

 to have emigrated. Total female density, including all 

 yearlings from the 1986 cohort, was the highest ever recorded 

 (3.3/km ) in spring. Net emigration reduced that to about 2.8 

 adult females/km 2 by autumn, equivalent to the previous high 

 in 1983. 



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