lower during autumn than other times of the year. Only 9.1% 

 of all deaths of marked fawns during 1976-1986 occurred during 

 autumn. During the early-mid 1970s, 1983, and 1984, coyote 

 predation on fawns was relatively high during autumn. It may 

 also have been high in some earlier years such as 1961. With 

 the possible exception of 1961, hunter harvests had only 

 negligible impact on fawn mortality. 



Over-winter mortality of fawns was important, but quite 

 variable. Of the fawns that died, 26.3% died during winter; 

 however, over-winter mortality rates for individual years 

 ranged up to 82%. Coyote predation was the proximate cause of 

 almost all (95%) of the fawn mortality during winters 

 1976-1986. Winter severity influenced fawn mortality rates, 

 but not in a simple manner. During most years, fawn mortality 

 increased with winter severity in a density-independent manner 

 (Fig. 6.14). Some years were exceptions, however, and very 

 high mortality occurred in both relatively mild and severe 

 winters, independent of density. Fawn mortality was 

 relatively low, even during severe winters, when microtine 

 populations remained high over winter (1968-69, 1978-79, 

 1982-83, and 1986-87). In either case, the highest winter 

 fawn mortality rates occurred in years preceded by 1-3 dry 

 summers that resulted in deer entering winter in poor 

 condition. Conversely, moderate fawn mortality during very 

 severe winters was preceded by one or more summers of 

 excellent forage conditions. This occurred when deer 

 densities were both high (1968-69) and low (1978-79). Thus, 

 general body condition and level of fat reserves as affected 

 by summer and autumn forage conditions, winter severity, 

 coyote and alternate prey population levels, all interacted to 

 influence winter mortality rates. 



Fawn mortality rates were not significantly correlated 

 with coyote density, but other factors, including forage 

 conditions, winter severity, and population levels of 

 alternate prey were related to fawn mortality rates. Such 

 other factors, at the least, influenced predation rates. This 

 indicated that coyotes and predation, although important, 

 probably were not always the ultimate or overriding factor in 

 fawn recruitment or population dynamics and regulation. 

 Rather, the role and importance of predation was tied to other 

 biological and environmental factors which simultaneously 

 influenced recruitment and numbers of deer on the area. 



Fawn survival to early winter was closely correlated with 

 forage production during most years. Because deer density did 

 not affect that relationship, forage quality (defined as the 

 succulence of vegetation) and the timing and length of the 

 period when green, succulent forage was available appeared to 

 be the controlling factor. Calculations of the quantity of 

 forage available, information on antler size and quality among 



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