Demographics of Gray Wolf (Canis lupus) Packs Recolonizing Variable Habitats in Central Wisconsin

Abstract – Some Canis lupus (Gray Wolf, hereafter Wolf) live in disjunct populations including Wisconsin's Central Forest Region (CFR), recolonizing there in the early 1990s. We examined how habitat factors and period of initial recolonization facilitated successful re-establishment of Wolves to this region. We divided this event into 3 periods: early (1994–1999), middle (2000–2005), and late (2006–2012). We defined habitat classes of individual pack territories as optimal, mixed, and marginal, based on: (1) percent public land, (2) percent agricultural land, and (3) road density. We analyzed the influence of time and habitat classes on pack territory size, winter pack size, pup presence, Wolf–human conflicts, human-caused Wolf mortalities, territory persistence, and reproductive performance. Pack demographics were similar across time, except pup presence was slightly lower during the middle period. Wolf–human conflicts increased over time and were correlated with population growth. Packs in marginal habitat were smaller in winter, exhibited lower reproductive performance, had more conflicts with humans, and experienced human-caused mortalities at rates 4 and 7 times higher than mixed and optimal habitats, respectively. We demonstrate that Gray Wolves tolerate some level of human-altered landscapes and identify demographic parameters that impact the Wolves' ability to survive in human-dominated landscapes.