9th International Deer Biology Congress

AUTHORS: Katey Huggler, Matthew M. Hayes – Wyoming Cooperative Fish and Wildlife Research Unit, Department of Zoology and Physiology, University of Wyoming, and Haub School of Environment and Natural Resources; Patrick Burke, Mark Zornes, Daniel Thompson – Wyoming Game and Fish Department; Kevin L. Monteith, Haub School of Environment and Natural Resources

ABSTRACT: Demography of large ungulates is typified by relatively high and invariable survival of adults. Consequently, survival of young is the demographic that often underpins population trajectories. In systems where ungulates co-occur with predators, predation is commonly the leading cause of mortality among neonates. Moreover, predator avoidance by females during parturition is common among ungulates to minimize risk of predation to newborns; this behavior involves increased use of habitat that provides adequate cover for neonates. If habitats that minimize predation risk are not consistent with those that offer energetic gain, however, such behavior may conflict with the need for females to acquire adequate forage to meet the energetic demands of lactation. Behaviors in response to forage acquisition and predation risk can have important consequences for fitness, and therefore, we aim to link behavior, nutrition, and predation to survival and reproduction in mule deer (Odocoileus hemionus) and elk (Cervus elaphus), two species that differ both in body size and behavioral strategies during parturition. We expect the sensitivity of habitat selection to predation risk by coyotes (Canis latrans) to vary as a function of body size and time post-parturition. Further, we expect that nutritional condition at the end of winter will influence whether parturient females adopt a risk-prone or risk-averse strategy, and such behavior should be related to neonate survival. Behavior is one of the primary mechanisms by which females cope with constraints on survival and reproduction. Thus, understanding the interacting roles of predation, habitat, and nutrition on behavior is key to identifying the mechanisms underpinning ungulate dynamics. High-desert systems in particular are ubiquitous across the West, therefore, identifying the factors contributing to thriving elk herds alongside of stagnant populations of mule deer in such a system is key to maintaining robust herds of elk and enhancing population growth of mule deer.