Sheep Losses on Selected Ranches in Southern Wyoming

Abstract

Highlight: To help resolve conflicting claims about the severity of predator losses to the sheep industry, sheep losses from all causes were assessed during 1973-75 in five southern Wyoming ranches. Although herd sizes varied seasonally and yearly, about 6,000 ewes and their lambs were monitored each year during spring lambing and the summer and winter grazing seasons. Most of the sheep were tended by herders. Lamb bss was greater than ewe, and spring losses were always greater than summer and winter losses combined. Of 4,440 dead sheep examined, predators killed 1,030 or 23%. Although predation was the largest single cause of death for lambs (24%), weather-related losses such as deaths from exposure, starvation, accidents or disease, if combined, would probably have been higher. Disease killed the most ewes (260/o), with predation the second most important cause of death (18%). Of the deaths from predation, coyotes caused 77%, black bears ll%, and golden eagles 9%. During the 3 years, known predator kills were 0.2% of the ewes each year and l.S%, 2.1%, and 3.2%, respectively, of the lambs from the study herds. There were 1,235 ewes and iambs missing, mostly after the summer season, mainly due to miscounting and loose management-from one ranch.

Seasonal Activity Areas of Coyotes in the Bear River Mountains of Utah and Idaho

“…Interpretations take on added significance from the perspective that some coyotes are found at high elevations during winter near areas used by domestic sheep in summer. Sheep using these mountain grazing allotments are frequently preyed upon by coyotes (Klebenow and McAdoo 1976, Nass 1977, Taylor 1977, Tigner and Larson 1977, Wagner 1988, Wagner and Conover 1997. Efforts to curtail such depredations frequently rely on aerial gunning to remove coyotes from these allotments during winter when habitat and flying conditions make such activities safer and more effective.…”

Coyote Control: The Public Response

“…The problem is, in large part, a perceptual one. Whether or not ranchers are losing substantial proportions of their flocks to coyotes-and there is some controversy regarding the significance of these predation losses (Cain 1975;Tigner and Larson 1977;Wagner 1975)-they believe that coyotes are a major threat to the sheep-raising industry (Buys 1975;Gee et al 1977). Whether or not coyotes are rural and urban pests and far from danger of extinction (Cain 1978), animal protectionists view them as part of our valuable wildlife resources and worthy of protection.…”

Coyote depredation management: current methods and research needs

“…Fences can be built that, when properly maintained, are nearly 100% effective at preventing coyotes from accessing livestock (deCalesta andCropsey 1978, Conover 2002). Birthing in sheds, keeping herders with livestock during the day, bedding animals near people for the night, removing or burying carcasses, and lighting corrals where stock are kept at night all have been suggested to reduce depredation (Davenport et al 1973, Nass 1977, Tigner and Larson 1977, Conover 2002. Guard animals may effectively protect livestock, though not in all circumstances.…”