Crying Wolf? A Spatial Analysis of Wolf Location and Depredations on Calf Weight

Abstract

Combining a novel panel dataset of 18 Montana ranches with spatial data on known wolf pack locations and satellite‐generated climatological data from 1995‐2010, we estimate the spatial impact of changing wolf pack locations and confirmed wolf depredations on the weight of beef calves. We find no evidence that wolf packs with home ranges that overlap ranches have any detrimental effects on calf weights. Other non‐wolf factors, notably climate and individual ranch‐specific husbandry practices, explained the majority of the variation in the weight of calves. However, ranches that experienced a confirmed cattle depredation by wolves had a negative and statistically significant impact of approximately 22 pounds on the average calf weight across their herd, possibly due to inefficient foraging behavior or stress to mother cows. For ranches experiencing confirmed depredation, the costs of these indirect weight losses are shown to potentially be greater than the costs of direct depredation losses that have, in the past, been the only form of compensation for ranchers who have suffered wolf depredations. These results demonstrate a potentially important and understudied aspect of economic conflict arising from the protection and funding of endangered species recovery programs.

Cost Effectiveness of Livestock Guardian Dogs for Predator Control

“…Throughout the previous analysis, the focus was exclusively on the direct costs (i.e., death loss) associated with predation. Yet, it may be that the indirect costs associated with predator presence and pressure are more significant than the direct costs of predation (Ramler et al 2014, Macon et al 2018). These indirect costs include, but are not limited to, lower reproductive rates, reduced body condition, and stress to the flock associated with confinement that is often used as a depredation strategy.…”

“…Further, we did not have access to data sufficient to estimate the indirect effects associated with predator pressures at HREC and, as a consequence, benefits associated with LGDs in this study are likely understated. Ramler et al (2014) is the only study known to the authors that has estimated indirect costs associated with predator pressure, namely the reduction in calf weaning mass caused by the presence of wolves ( Canis lupus ) in western Montana, USA. Although this is only one aspect of indirect costs possibly suffered by ranchers, and is clearly not directly analogous to a sheep operation, it is our only available estimate.…”

Foraging theory and the propensity to be obese: an alternative to thrift

“…[ (Blanchard et al 1995;Carlsen et al 1999;Higginson et al 2012Higginson et al , 2016Monarca et al 2015;Ramler et al 2014;Thaler et al 2012;Tidhar et al 2007). Although this has been generally interpreted as a "stress response" (Kestemont and Baras 2007) it is likely that it is a strategic response of the system evolved to optimize foraging gains against foraging risk (Tidhar et al 2007).…”

Direct and Indirect Impacts to Ranchers from Wolves and Other Predators: Building a Baseline in California

“…While the direct economic cost of livestock predator losses are relatively easy to define, emerging work suggests that indirect impacts are potentially more costly for livestock producers (Ramler et al 2014). Livestock production losses due to stress and harassment from wolves can be significant, possibly exceeding the economic value of killed animals.…”