-autumn and 6.2% (<l-24.8%) died during winter-spring. 

 Overwinter mortality rates based on numbers of females alive 

 on 1 December were slightly higher, averaging 7.1% and ranging 

 from <1% to 30.3%. 



Most summer-autumn mortality of adult females occurred 

 during the hunting season. Only 5 (12.5%) of 40 deaths of 

 marked females for that period were attributed to causes other 

 than hunting. Because hunting during 1975-1980 was for males 

 only, all mortality of females during autumn of those years (X = 

 1.9%) resulted either from natural causes or illegal kills. 



Total annual mortality of adult females exceeded 

 recruitment of yearling females during 11 of 26 years (Table 

 6.2). Harvest alone was sufficient to reduce the population 

 during 7 years: 1961, 1964, 1971-1974, and 1984. During 1964 

 and 1984, annual harvest rates were below the long-term 

 average recruitment rate, but annual recruitment was much 

 below average. Harvest rates were near the average 

 recruitment rate during 1971-1974, but annual recruitment was 

 below average each year. Harvest rate exceeded the long-term 

 average recruitment rate for females only in 1961. 



Mortality during winter, alone, was sufficient to reduce 

 the adult female population during 1964-65, 1971-72, 1975-76, 

 1983-84, and 1984-85. During 1962-63 and 1965-66, the 

 combination of hunting and winter mortality was greater than 

 recruitment. In 1964-65, 1971-72, and 1984-85, both hunter 

 harvest and winter mortality exceeded recruitment. However, 

 winter loss was greater than average recruitment only during 

 1971-72. 



Based on average recruitment rates and the theories of 

 compensatory mortality and recruitment, hunting mortality of 

 adult females was excessive only during 1961. During 3 

 periods, 1964-1965, 1971-1976, and 1983-1985, however, annual 

 recruitment was much below the long-term average and 

 compensatory mortality and recruitment did not operate 

 according to theory. Thus, the use of average recruitment 

 rates and the theories of compensatory mortality and 

 recruitment did not provide a viable basis for determining 

 sustainable harvests of adult females. 



Male Mortality Patterns 



Annual mortality for adult males averaged 41.3% (Table 

 6.3), more than twice the rate for adult females. Annual 

 mortality ranged from 17.4% (1978-79) to 58.0% (1981-82). 

 Mortality from hunting averaged 37.5%, more than 3 times the 

 average for adult females. Winter mortality, however, 

 averaged only 3.8%, about half that for females. The highest 

 rate of winter mortality for males was 11.4% during 1971-72. 



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