Multi-scalar habitat selection unveils ecological domains in wolves when selecting rendezvous sites

Abstract

Wolves are known to be habitat generalists, but they may have critical requirements during key life-cycle stages, such as reproduction and pup rearing. Especially in human-dominated landscapes, wolves may become particularly choosy concerning the location of their homesites to reduce human-related risk and disturbance, thus enhancing pup survival. From 2005 to 2010, we investigated habitat selection by wolves when establishing the territory at the landscape scale (i.e., 2nd order selection) and when locating rendezvous sites within the territory (i.e., 3rd order selection), the latter based on 31 acoustically and field-verified rendezvous sites (RVs) in 8 packs in the Abruzzo Lazio and Molise National Park, a historical stronghold of the species in central Italy where wolves always coexisted with humans. Using a hierarchical, multi-scale habitat selection approach through multi-grain resource selection functions (MRSFs), we investigated environmental, topographic, and anthropogenic factors affecting territory and RVs selection by wolves. At the landscape scale, wolves avoided human settlements and primary roads and selected forested areas, shrubland, and rough terrain, likely to improve concealment and decrease human-associated risks; however, they also positively selected pastures and trails to possibly improve efficiency in hunting and traveling. When locating RVs within the territory, wolves still selected forested areas, shrubland, and pastures but differently than the 2nd order, they avoided anthropogenic linear features (secondary roads and trails) and rough terrain. Our findings confirm that habitat selection by wolves is better understood through a multi-scalar approach, which may reveal trade-offs in selection decisions across different spatial scales.