Modeling Large Carnivore and Ranch Attribute Effects on Livestock Predation and Nonlethal Losses

Predator-livestock interactions are a major concern for both agriculture and conservation globally. Using retrospective survey data from 274 ranches in Wyoming, United States, we used information theory to model how ranch attributes and large carnivores influenced the timing, duration, and severity of livestock predation. We then used constrained ordination to understand how 1) landscape, weather, and animal features influence predation and 2) how livestock behavior and nonlethal loss relate to ranch attributes and large carnivores. Timing, duration, and severity of livestock predation were generally not explained by ranch size or number of counties but were explained by livestock type, livestock parturition (either timing or duration), and documented large carnivore loss. Addition of the large carnivore loss variable to global models always improved Akaike information criterion scores. Rangelands characterized as rough, forested, shrubby, or a public grazing allotment reportedly increased predation risk, in part, due to large carnivore exposure. Approximately two-thirds of participants noticed livestock nervousness if a predator was nearby, half of participants noted changes in livestock distribution patterns, and a quarter of participants noted a reduction in livestock grazing time. Nonlethal losses such as lower weight gains, lower conception rates, lower birth rates, and delayed birth season were reported by 27%, 19%, 12%, and 11% of participants, respectively. Ordination revealed separation between behavioral changes and nonlethal losses, attributed to large carnivore exposure. Parturition relative to livestock type was also strongly correlated to timing and duration of predation for cattle-only operations but not for operations with sheep. The predictive cattle predation-parturition model suggests that for each additional month of calving, producers should anticipate 21 additional d of predation. Understanding predator-livestock interactions relative to ranch and rangeland features, parturition, large carnivore exposure, and losses that extend beyond mortalities can assist in developing novel strategies to mitigate lethal and nonlethal losses.The Rangeland Ecology & Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information

Contemporary Livestock–Predator Themes Identified Through a Wyoming, USA Rancher Survey

Livestock-predator interactions structure ranchers' perceptions of predators. We surveyed 274 ranchers in Wyoming using open-answer questions about contemporary livestock-predator themes. Four themes emerged: 1) difficulty mitigating losses from protected large carnivores; 2) escalating impacts of predatory birds on livestock and wildlife; 3) sustainability of predator management funding; and 4) continual bureaucratic complexities of predator management. Themes had an underlying thread regarding the tension between state control versus federal control including concern about growing predator populations that may affect both livestock and native wildlife such as greater sage-grouse (Centrocercus urophasianus).The Rangelands archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information

Meta-analysis of diet composition and potential conflict of wild horses with livestock and wild ungulates on western rangelands of North America

Wild horse (Equus ferus caballus) management in western North America is an escalating concern for ecological integrity on these landscapes. Identifying potential diet overlap among horses, livestock, and wildlife will inform management decisions to optimize multiple interests.To understand dietary relationships, we conducted a quantitative synthesis of microhistological fecal studies for wild horse, beef cattle (Bos spp.), domestic sheep (Ovis aries), elk (Cervus elaphus), pronghorn (Antilocapra americana), and mule deer (Odocoileus hemionus) diet composition on western rangelands of North America. Our search yielded 60 studies from 14 states, 1 Canadian province, and 2 Mexican states with 392 unique species-season samples. We summarized plant species into graminoid, forb, and browse functional groups. For wild horses, seasonal diet composition means for graminoids (77-89%), forbs (4-15%), and browse (3-10%) did not vary seasonally for any plant group (P ≤ 0.05). Univariate analyses and the calculation of effect sizes corroborated our finding that graminoid composition explained the potential overlap of wild horses with cattle regardless of season, with sheep and elk in the spring, with sheep in the summer, and with elk in the fall and winter. Although data indicate wild horse diets are primarily composed of graminoids, several studies reported unusual, regionally specific shifts in response to winter snow that limited graminoid accessibility, leading to higher browse composition. Season, plant composition, and ungulate assemblage may all influence dietary competition between wild horses and other large ungulate sharing western North American rangelands; however, the low and nonsignificant heterogeneity values at alpha 0.01 for cattle:horse effect size comparisons suggest that cattle and horses respond to regional and seasonal variation similarly - A result not observed for other ungulate:horse comparisons. Our meta-analysis provides a robust data set for evaluations of diet composition for wild horses, livestock, and wildlife, whereas no empirical studies have assessed all species together. © 2016 The Society for Range Management. Published by Elsevier Inc.The Rangeland Ecology & Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information

Ecological Sites: Can they be Managed to Promote Livestock Production?

We assessed diet quality and livestock weight gains for shortgrass steppe pastures dominated by Loamy Plains or Sandy Plains ecological sites. When growing season precipitation is “normal,” livestock gains are higher on Sandy Plains ecological sites, and diet quality is not limiting livestock production. Conversely, when growing season precipitation declines by ≥ 20%, digestible organic matter, but not crude protein, influences livestock gains. These negative effects on livestock gains are more pronounced for the Loamy Plains ecological site. Pastures with multiple ecological sites may provide range managers greater forage diversity for livestock and higher livestock gains during dry growing seasons.The Rangelands archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information