Abstract
Wolves (Canis lupus) are born in an altricial state and require extensive care in the early stages of life as they are born blind, naked, and unable to hide. In their first weeks they stay around the den, and as such, the wolves’ choice of den location is crucial to the survival of the pups. In this study, I collected data from 40 previously active wolf dens within the core breeding area in Norway and Sweden, where the wolves live in a mostly human-altered landscape with a vast road network due to commercial forestry. I investigated the role of the environment as concealment along with how human infrastructure impacts their choice of den sites and provide key characteristics of the different den types. For denning, wolves preferred steep areas and dense forest far from buildings at an intermediate distance from forest roads. Paved roads were never the closest road for any of the dens. Den types varied in structure, from boulders and overhangs, to excavated anthills and toppled tree roots. Most dens were selected in a way that provided shelter and some sort of concealment. Almost half (45%) of the dens were located in between or excavated under boulders, which would be hard to identify as dens for humans, thus providing an additional layer of concealment. In the immediate area surrounding the den, canopy and visibility proved to be the most significant for the wolves’ selection of den sites. As they selected dense steep forest for their general denning area, they selected even denser and more concealed den sites. Variation in habitat selection among the different wolf pairs suggests an adaptive selection, and a possible trade-off between tolerating short term human presence and selecting good denning areas.
