severe 1971-72 winter (C.R. Watts, unpublished data). In 

 contrast with our study area, however, fawn survival 

 subsequently increased sharply after 1972 to a high of 109 

 fawns: 100 adults in winter 1974-75. We did not observe 

 increased fawn survival until 1978-79 despite good to 

 excellent forage conditions through the period on both areas. 

 The major apparent difference between the areas was that 

 coyote control involving intensive private aerial hunting 

 during winter occurred at Sage Creek; no equivalent control 

 occurred on our study area. 



Other data also suggested that coyote predation on deer 

 may have been abnormally high during 1973-1975, especially in 

 relation to forage conditions on the study area. Normally, 

 when data were obtained for all species, annual production and 

 survival of young followed similar trends in mule deer, 

 white-tailed deer, antelope, and elk on the area. For example, 

 survival of young was the highest ever recorded for all 4 

 species during 1979 and was above average for all during 1986. 

 All species experienced below-average survival of young in 

 1976, 1977, 1984, and 1985. During 1973-1975, survival of 

 mule deer fawns was much below average each year; survival of 

 whitetail fawns was below average during both years for which 

 data were obtained; and survival of antelope fawns was below 

 average during 1973 and 1974 and average during 1975. In 

 contrast, elk experienced average calf survival in 1973 and 

 above average survival in 1974 and 1975. 



Forage production and presumably fawn hiding cover was 

 above average during all 3 years, especially in 1974 and 1975, 

 and density of all species was low. Thus, the only difference 

 between elk and mule deer, white-tailed deer, and antelope 

 must have been related to the relative vulnerability of their 

 young to predation by coyotes. The larger size of elk calves 

 and the tendency of elk to form large nursery groups probably 

 rendered them less susceptible to coyote predation. 



There was some evidence that non-density-related forage 

 deficiencies can contribute to the intensity of coyote 

 predation on fawns. Forage-vegetation conditions appeared to 

 influence behavioral patterns of deer and the vulnerability of 

 fawns to predation. They also influenced coyote behavior with 

 respect to predation on deer, especially through their effects 

 on alternate prey populations . 



Coyotes hunt deer primarily by sight, and it usually is 

 necessary for them to maintain visual contact with the deer to 

 successfully complete a kill. Because of this and the 

 tendency of fawns to remain bedded and well hidden when not 

 nursing during the first few weeks of life (Riley and Dood 

 1984), most attempts at predation occur after coyotes have 

 observed a fawn active around the doe during nursing bouts 



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