White-tailed Deer (Odocoileus virginianus) Fawn Survival and Seasonal Movement Patterns of White-tailed Deer and Coyotes (Canis latrans) in the Cleveland Metropolitan Area
Sara Kennedy, MS
Advisor: Stanley Gehrt
White-tailed deer () and coyotes () are challenging wildlife species to manage in urban areas. Deer often reach densities which exceed cultural and ecological carrying capacities. Varied public opinions of both species present additional challenges. Cleveland Metroparks implements a population model to guide management efforts to reduce deer densities. However, two elements of the model lacking reliable estimates are fawn survival and migration across park boundaries. Also, the influence of coyotes on deer dynamics is unknown for urban systems. To develop better estimates of survival and habitat use and to understand the coyote-deer relationship, we conducted a multi-year study to quantify coyote and doe movement and fawn survival. Six coyotes were collared with GPS transmitters. Twenty-nine adult deer were captured; seven pregnant does received a radio collar and vaginal implant transmitter. Fifty-seven neonatal fawns were captured and fitted with expandable radio collars. We recorded 22 fawn mortalities. Vehicle strikes and culling were the most common causes of mortality. Average six month survival was 78%. Factors with the potential to influence fawn survival were modeled using known-fate models in Program Mark in a two-step process, first incorporating intrinsic covariates and then adding spatial and habitat covariates to the best-supported model from the first step. The best supported models varied with the time period of the analysis, but all included age class. Additional covariates included in one or more top models included habitat composition, home range size, and road density. Habitat use and selection were examined on a seasonal basis. For does, location data was divided into pre-parturition and post-parturition. Fawn locations were examined at three age classes: birth to two weeks, two to eight weeks, and older than eight weeks. Coyote locations were classified into three periods of differing levels of fawn vulnerability: pre-fawn (March – April), hiding (May – June), and fleeing (July – August). For coyotes, we calculated overlap indices between seasonal home ranges and core use areas. Both does and fawns used natural habitat out of proportion with availability. Both showed little seasonal change in habitat use or selection, although some does increased their use of open habitat post-parturition. Habitat use by fawns showed more variation between individuals than between seasons. Coyotes showed substantial individual variation in all spatial metrics, but a majority increased their use of forested habitat during the hiding period. Seasonal overlap indices varied from 6.2% to 82.5% for home ranges and from 0.0% to 42.9% for core use areas. Improved estimates of population parameters for urban white-tailed deer can aid in management of this potentially overabundant species. Our work demonstrates that fawn survival can be high in urban areas and reinforces the link between urban parkland and surrounding residential areas for managing urban wildlife.