Response of Erethizon Dorsatum and Lepus americanus to specialized and generalized predators BIOS 35502 Practicum in Field Biology

The way that animals balance foraging needs with predation is a very interesting and widely studied subject in ecology. The purpose of this study is to determine whether the porcupine (Erethizon dorsatum) and snowshoe hare (Lepus americanus) have a response to the increased danger that a specialized predator, the fisher (Martes pennanti), poses over a general predator, the coyote (Canis latrans). Sticks soaked in brine were put out in different environments with three treatments of no scent, coyote urine, or fisher scent. The porcupine showed an overall reaction of preferring sticks with no scent (p=0.016) although they did not show a differential response to either predator (p=0.72). The hare showed no preference for sticks without scent (p=0.074) as well as no different reaction whether the scent was fisher or coyote (p=0.69). Environment also played no role in foraging choice (p=0.16). There was an issue with sample size that if solved could lead to the expected result that fisher scent has more of an effect than coyote urine. Introduction Natural selection predicts that all animals behave in a way that will maximize their potential fitness. Many experiments have shown that, in the presence of predators, prey balance their safety with the perceived benefits of other necessary functions to increase fitness, such as foraging for food and reproduction (Peckarsky et al 2008, Milinski and Heller 1978). The behavioral response of prey species to potential predators is a widely studied and important topic in ecology. In the presence of a wolf (Canis lupus) population, elk (Cervus canadensis) drastically changed their foraging behavior, affecting the trophic cascade of their home forest (Fortin et al. 2005). Experiments have tested the feeding