Hunting method affects cortisol levels in harvested mountain hares (Lepus timidus)

Abstract

The direct effects of hunting on hunted individuals and populations have been well known for a long time. However, recently there has also been an increased focus on the indirect, non-lethal effects of hunting. When approached by a possible threat such as a predator, the prey releases various stress hormones into the bloodstream. Cortisol is one of these hormones and the blood concentration is an indicator of stress levels in mammals. Here we report on a study on the effects of using hunting dogs versus walk-up shooting on mountain hare blood cortisol levels. We sampled 20 hares hunted using dogs and 32 control hares hunted without using dogs. On average the cortisol level in hares hunted using dogs was 44.6 ng/ml, while in hares harvested without being chased by dogs it was 6.8 ng/ml. Based on the blood hormone levels of this study we cannot conclude if the elevated cortisol levels we see in the hares hunted using dogs was harmful to the hares had they not been shot. However, given what is known about the effects of chronic stress, we would caution against repeated chases of individual hares. The cumulative effect of stressors including hunting is likely crucial for any effects on reproduction and survival. Thus, there is a need to evaluate the long-term effects of hunting chases and other human activities on mountain hare stress hormone levels, and to investigate the long-term effect on hare behavior, space use, survival, reproduction and recruitment.

Hunting method affects cortisol levels in harvested mountain hares (Lepus timidus)