Predators and Wildlife Corridors
North America still carries the legacy of predator control from early parts of the 20th century where government agencies exterminated predators such as wolves and bears from much of their range. Restoration of these once rare predators has become an important conservation and societal goal in the last 2 decades, most notably with the restoration of wolves to Yellowstone National Park in 1995. Mark's research includes understanding the effects of wolf restoration in National Parks such as Banff and Yellowstone National Park. In Banff National Park, Alberta, predation by wolves was shown to reduce elk numbers and modify elk behavior enough to result in reduced elk densities in areas with wolves. This, in turn, lead to reduced herbivory by elk on native vegetation such as aspen and willow. These effects cascaded down to other species that depended on willow, such as beavers and riparian songbirds. Thus, the effects of the restoration of top carnivores such as wolves were felt throughout the food chain, and recent studies in other systems confirm the important role wolves play in terrestrial ecosystem dynamics.
Unfortunately, many areas have undergone extensive human development since wide-ranging carnivores like wolves and grizzlies last roamed there. In some areas, habitat and corridor restoration may be required to maintain recovering populations of carnivores. In Banff National Park, wolves did not use wildlife corridors surrounding the townsite of Banff enough, which lead to the development of an urban elk population which damaged native vegetation and caused dramatic human-wildlife conflicts. Mark's research demonstrated the positive effects of wildlife corridor restoration through facility removal and human use management that lead to increased wolf use of wildlife corridors in the area. By applying wildlife data with spatial models of habitat and connectivity in geographic information systems (GIS), restoration ecologists will be able to work at restoring wildlife habitat throughout North America. As human populations grow, especially in the intermountain west, wildlife habitat restoration will be an ever-important field of applied and basic research.