Predation risk, elk, and aspen: comment

• Published in: Ecology
• Main Authors: Beschta, Robert L., Eisenberg, Cristina, Laundre, John W., Ripple, William J., Rooney, Thomas P.
• Format: Text
• Language: unknown
• Published: Hosted by Utah State University Libraries 2014
• Subjects: Agriculture; Ecology and Evolutionary Biology; Forest Sciences; Genetics and Genomics; Plant Sciences; Kay; Alces alces; Canis lupus
• Online Access: https://digitalcommons.usu.edu/aspen_bib/7333; https://doi.org/10.1890/13-1624.1

With the exception of humans, gray wolves (Canis lupus) are perhaps the most significant predator of cervids in the northern hemisphere, mainly due to the group-hunting, year-round activity, and widespread geographic distribution (Peterson et al. 2003). Thus, interactions between wolves and large herbivore prey, such as elk (Cervus elaphus) and moose (Alces alces), have long been of interest to biologists (Peterson 1995, Jęodrzejewska et al. 2000, Mech and Boitani 2003). The potential ecological role this apex predator may have, via trophic cascades, has also received attention in recent years by researchers (e.g., Callan et al. 2013, Kuijper et al. 2013, 2014), wildlife management agencies (e.g., state wolf management plans), as well as the general public. Perhaps nowhere in the western United States has a heightened examination of this large predator been more focused than in Yellowstone National Park (YNP; Laundré et al. 2001, Smith et al. 2003, 2013, Fortin et al. 2005). Here, wolves were reintroduced in the mid-1990s, again completing the park's large predator guild after approximately seven decades of absence, thus providing a long-term, landscape-scale, natural experiment (Diamond 1983). The Gallatin winter range is one of two that occur along the northern portion of YNP, the other is the northern ungulate winter range, or “northern range,” located some 25 km or more to the east. Of these, the Gallatin has been less studied. Nevertheless, the Gallatin winter range, like the northern range, experienced high levels of elk herbivory following the extirpation of wolves in the early 1900s. Over a period of approximately seven decades, intensive herbivory by elk led to the long-term decline in aspen (Populus tremuloides) and willow (Salix spp.) recruitment (i.e., growth of young plants above the browse level of elk) in the Gallatin winter range, leaving these plant communities in an impoverished condition (Lovaas 1967, Patten 1968, Kay 2001, Ripple and Beschta 2004, Halofsky and Ripple 2008). Accelerated soil ...