Reactions of roe deer to human disturbances and wolf predation in a Polish forest.

Antipredator responses of prey are important because of their potential trophic cascade effects. Predator responses are especially important for species that impact the economy, such as ungulates. Past research has focused on the behavioral adaptation of roe deer, the most common ungulate in Europe, to human and lynx pressure. However, the European wolf population has increased in the last decade and in some recently recolonized parts of Poland roe deer constitute the largest food source for wolves. Unlike in moose and red deer, no evidence has yet been found for changes in the vigilance-foraging time ratio in roe deer in response to wolves. We took the unique opportunity to study the behavior of roe deer during the partial recolonization by wolves of a large forest complex (Tuchola Forest) in Poland. Using video cameras, we found that roe deer react differently to the presence of wolves compared with humans. Wolf predation increases roe deer movement. In comparison, anthropopressure causes roe deer to mainly use an avoidance strategy, limiting their activity to times of day when people are not present. This temporal avoidance strategy was similar whether human pressure resulted from recreation or hunting.