Causes and Economic Effects of Mortality in Livestock Guarding Dogs

Abstract

We assessed causes of pre-senile mortality among working guarding dogs, and its effects on their manrgement and cost. A population of 449 livestock guarding dogs in 31 states showed no differences in mortality due to breed or sex, but dogs working on open rangelands died more frequently (p<.OOl) than those working on farms or fenced ranches. Half of the farm dogs died before they reached 38 months of age, by which time nearly three-quarters of the open rangelands dogs had succumbed. Accidents accounted for over half the deaths, culling for inappropriate behavior accounted for one-third, and diseases for 9%. High accident and culling rates in young dogs substantially increased the cost of this predator control technique. However, we found 2 main areas where corrective measures can be applied: (1) increasing the awareness among producers that accidents are a main cause of deaths especially during the dogs’ first 30 months of age; and (2) reducing the number of culls by improving the genetics of the dogs and by training producers to manage them. Eurasian livestock guarding dogs (Canis familiaris) can reduce or eliminate predation on sheep (Ovis aries) and goats (Capra hireus) on farms and ranches in the United States (Coppinger et al. 1983a,b; Green and Woodruff 1983a). Such reduction depends on dogs being attentive and trustworthy. Dogs deficient in either of those attributes are unsuccessful. Methods of predator control must be economical to be useful. Although guarding dogs are proving to be of reasonable cost, producers need to be aware of factors that can rapidly change the economic picture. Green et al. (1984) estimated dollar costs of guarding dogs and suggested that ability to deter predators and longevity are additional factors that influence costs relative to benefit. We examined the effect of ability and longevity on working guarding dogs. Specifically, we looked at: (1) the duration of guarding behavior, which is partially dependent upon the life span of the dog, and (2) the percentage of dogs that show appropriate guarding behavior. The longer a dog lives, the more cost-effective it will become, because the costs of purchase and training can be amortized over a longer period. Moreover, a longer life span makes the generally ineffective juvenile months a smaller percentage of the total. We assessed causes of pre-senile mortality among working guarding dogs, and its effects on their management and cost. In addition, we developed actuarial statistics that will assist producers, researchers, veterinarians, and breeders in keeping track of the age structure of a population of working guardians, and in planning for replacement animals.