The lack of a relationship between deer density (across 

 the range of densities we observed) and mortality rates may be 

 another reason that there was little evidence of compensatory 

 mortality among adult females. Over-winter mortality of adult 

 females was not significantly related to either total number 

 of deer (r=0.03, P>0.50, df=27) or total number of adult 

 females (r=0.08, P>0.50, df=25) entering winter. It also was 

 not related to the number of adult females in the population 

 the previous summer (r=0 . 15 , P=0.47, df=27). 



Increased survival of deer remaining after harvest is 

 most often based on the assumption that winter forage is in 

 short supply and limiting deer numbers. It also assumes that 

 harvesting deer prior to winter increases the quantity of 

 forage available per capita for remaining deer, thereby 

 increasing their condition and survival. If winter forage 

 supplies are not limiting, as in this study, neither 

 assumption holds, and much of the rationale for compensatory 

 mortality is gone. Although it may also be argued that 

 reducing deer numbers through hunting could increase per 

 capita forage during other times of the year, we also found no 

 evidence that the quantity of forage during other seasons was 

 limiting, nor that mortality responded to deer density at any 

 time of the year, or in a delayed manner. To clear up 

 possible objections or confusion over terms, we note here that 

 we have already (Chapter 5, earlier discussion this chapter) 

 indicated that we had no evidence for density-dependent 

 compensatory reproduction. Thus, hunting mortality of adult 

 females resulted in little substitution (compensatory 

 mortality) , no measurable decrease in mortality as the result 

 of increased per capita forage, and no compensatory 

 reproduction. 



Although hunting mortality was a major cause of mortality 

 for adult females, hunting mortality rates were low to 

 moderate, and generally below long-term average recruitment 

 rates. Only during 1961, 1964, 1971-74, and 1984 was hunting 

 mortality of adult females, by itself, greater than subsequent 

 recruitment. During those years, however, recruitment was 

 much below average. 



A stable population can be maintained with some adult 

 mortality in all years because at least some fawn recruitment 

 always occurs. In some years, however, the natural mortality 

 rate among adult females was higher than recruitment. Thus, 

 the availability of a "harvestable surplus" of adult females 

 varies among years. It could also vary with management goals; 

 i.e, to increase, stabilize, or decrease numbers of deer in 

 the population. The ease with which harvest can decrease 

 population size during years or periods of low recruitment 

 and/or high adult mortality was demonstrated by population 

 trends during 1961-1962 and 1972-1974. 



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