Habitat Interference by Axis Deer on White‐Tailed Deer

Abstract

: Many studies of interactions between exotic and native ungulates have not had temporal and spatial controls nor have they considered the types of competitive interactions that would allow coexistence. For exotic axis deer (Axis axis) and native white‐tailed deer (Odocoileus virginianus) to coexist one species should be superior at interference competition and the other species should be superior at exploitative competition. We generated and tested predictions, based on body size and diet breadth, about habitat selection by white‐tailed deer in the presence and absence of axis deer, dominance relationships, and time at sites provisioned with high quality forage. We conducted our study in treatment (axis and white‐tailed deer) and control (white‐tailed deer only) areas when both species were present and after axis deer were removed. We conducted vehicle surveys to determine habitat use of both species. At provisioned feeding sites we recorded aggressive behaviors and amount of time species spent at feeding sites alone and together. In the treatment area white‐tailed deer selection for wooded habitat increased 2.1 times after axis deer were removed, whereas habitat selection by white‐tailed deer was constant in the control area over the same time. At feeding sites axis deer were dominant to white‐tailed deer; both species spent a significantly greater amount of time alone than at feeders together, but amount of time that individuals of each species spent at feeders did not differ. Axis deer were superior at interference competition, but white‐tailed deer were not superior at exploitative competition; thus, species coexistence is unlikely. Whether white‐tailed deer are negatively impacted by axis deer at spatial scales larger than our experiment probably depends on abundance of axis deer at larger spatial scales. Experiments of species interactions with temporal and spatial controls that consider types of competitive interactions increase a manager's understanding of when and how native ungulates may be negatively impacted by exotic ungulates.

Microhabitat of small mammals at ground and understorey levels in a deciduous, southern Atlantic Forest

“…The negative impact that exotic species may cause in the native fauna is well known (Lowe et al 2000), and we highlight the associated risk of diseases transmission and competition with the native assemblage (e.g. Crowl et al 2008, Fass andWeckerly 2010).…”

Ecological niche overlap between co-occurring native and exotic ungulates: insights for a conservation conflict

“…It has also been detected that exotic species may affect the genetic diversity and the evolutionary pathway of native species (Mooney and Cleland 2001). This phenomenon has been evaluated in different areas of the world; e.g., introduced carnivores into Australia (Doherty et al, 2017) or Europe (Bonesi et al, 2004;Harrington et al, 2009), or between exotic and native deer in North America (Faas and Weckerly 2010).…”

Dietary overlap and potential competition in a dynamic ungulate community in Northwestern Canada

“…Globally, native ungulates are frequently among the most culturally and socio‐economically important wildlife species to local people, and threats to their persistence are often of critical concern. As a result, several studies were prompted by the introduction of livestock (e.g., Awan et al , Hong‐Jun et al , Liu and Jiang ) or introduced species (e.g., Kirchoff and Larsen , Faas and Weckerly ) onto native ungulate ranges. Yet, other studies have investigated the potential impact of interspecific competition on threatened species (e.g., Li et al , Vila et al , Namgail et al ).…”