in areas of low relief would be lower than apparent in sex and 

 age classification data. Despite these considerations, which 

 minimize differences in classifications, fawn survival was 

 generally poorest in areas of low relief during both early 

 winter and spring (Fig. 6.2). However, during years of higher 

 fawn survival, fawn survival was as high or higher in areas of 

 low relief as in areas of greater topographic relief. 



Numbers of adult females observed in areas of low relief 

 during early winter helicopter surveys declined earlier and 

 recovered later than in areas of greater relief. Numbers in 

 areas of low relief declined from 1970 through 1978 and 

 started to recover by 1979 (Fig. 6.3). The number of females 

 in areas of greater relief did not decline until 1972, reached 

 a low during 1976, and began to recover in 1977, 2 years 

 earlier than in areas of low relief. The number in areas of 

 low relief reached a peak in 1981 and declined following 

 mortality during the winters of 1981-82, 1983-84, and 1984-85 

 (Figure 6.3). On the other hand, females in areas of greater 

 topographic relief continued to increase through 1984 and then 

 declined. These data substantiate those provided by marked 

 deer in that deer numbers in areas of low relief were most 

 affected during winters of relatively high mortality. These 

 data are not precise comparisons because some year-to-year 

 fluctuations in relative numbers between areas could have 

 resulted from changing proportions of migratory females in the 

 2 areas at the time of the surveys and changes in relative 

 observability between years. 



Relative numbers of total deer in the 2 types of habitat 

 during spring were even more difficult to interpret than 

 numbers during early winter. This occurred because there was 

 even more variation between years in the location of migratory 

 females at the time of spring surveys. During spring 1978, 

 1979 and 1982 (after severe winters) most migratory females 

 remained in areas of high topographic relief through the time 

 of spring surveys. During those years, total numbers of deer 

 using areas of low relief during spring were underestimated, 

 and numbers using areas of high relief were overestimated. 

 The data (Fig. 6.4) do indicate, however, that there were very 

 few deer resident yearlong to areas of low relief during 1978 

 and 1979. After 1982, spring surveys were flown later than 

 previously and most migratory females had returned to areas of 

 low relief at the time of the surveys. Although not ideally 

 controlled, the data seemed sufficient to indicate that 

 numbers of deer in areas of low relief decreased more than 

 those in areas of greater relief. This differential decline 

 occurred both during the population low of the mid-1970s and 

 the population decline from winter 1983-84 through spring 

 1986. 



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