during years when they were in relatively good condition. 

 Inexperienced behavior might also explain the relatively high 

 predation rate we observed for yearlings as compared with 

 older deer. 



Many deer killed by coyotes were found on ice along the 

 Missouri River or Fort Peck Reservoir, but many were also 

 found in uplands. The incidence of coyote kills on the river 

 and reservoir apparently peaked in the mid 1970s, because 

 relatively fewer remains of deer were found on those sites 

 after 1976. Most upland kill-sites were located at the base 

 of steep slopes and in sharply cut drainage bottoms. Evidence 

 indicated that the kills were usually accomplished when the 

 deer fell down on the steep, icy slope or bottom. Snowfall 

 followed by periods of melting and severe cold that caused ice 

 to form on those sites often preceded abnormally severe 

 predation on deer (Knowles 1976 and personal observations). 

 These conditions could cause the fall and perhaps injury of 

 any running deer. Often, when investigating these kill sites, 

 we had to use hand-holds on shrubs to move across the slope. 



Because the deer apparently were in relatively good 

 condition, the high losses during winter 1975-76 (Knowles 

 1976) appeared to be related to icy conditions that prevailed 

 as well as the low alternate prey populations that year. 

 Similar icy conditions prevailed during the relatively mild 

 winters of 1983-84 and 1984-85. Despite poor body condition 

 and relatively high mortality, most deer survived both of 

 those winters in worse physical condition than many deer 

 killed by coyotes in other years. Similarly, Shaller (1967) 

 reported that predation by tigers... "is not confined to the 

 young, old, sick, and surplus animals, but that prime ones are 

 also readily taken" . He also pointed out that the method of 

 hunting is less important in determining the class of animals 

 killed than the characteristics of the prey population. 



Mortality of Adult Females 



Hunting was the major known cause of death among adult 

 females . Coyote predation ranked second among known causes 

 and was suspected to be at least the proximal factor in most 

 mortality for which cause was undetermined. 



Most hunting mortality of adult females apparently was 

 additive to other mortality. During 13 years (1960-1972) with 

 a hunter bag limit of 2 deer of either sex, total annual 

 mortality averaged 22.2% for adult females. For 6 years with 

 a 1 deer, either sex, bag limit (plus a very small number of 

 second tags during 4 years), the average was 17%. During 8 

 years in which only males were legal (except for 0.08 and 0.16 

 antlerless tags/mi 2 during 1985 and 1986), average annual 

 mortality of adult females was 7.2%. During these same 



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