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Wildlife Research Wildlife Research Society
Ecology, management and conservation in natural and modified habitats
RESEARCH ARTICLE

Response of white-tailed deer to removal of invasive wild pigs

Matthew T. McDonough https://orcid.org/0009-0002-6253-7324 A * , Robert A. Gitzen A , Stephen J. Zenas A , Mark D. Smith A , Kurt C. VerCauteren B and Stephen S. Ditchkoff A
+ Author Affiliations
- Author Affiliations

A College of Forestry, Wildlife and Environment, Auburn University, Auburn, AL 36849, USA.

B United States Department of Agriculture, Animal and Plant Health Inspection Service (APHIS), National Wildlife Research Center, Fort Collins, CO 80521, USA.

* Correspondence to: mtm0075@auburn.edu

Handling Editor: Aaron Wirsing

Wildlife Research 51, WR23097 https://doi.org/10.1071/WR23097
Submitted: 11 August 2023  Accepted: 19 September 2024  Published: 2 October 2024

© 2024 The Author(s) (or their employer(s)). Published by CSIRO Publishing

Abstract

Context

With the range expansion of invasive wild pigs (Sus scrofa) in North America during the past decades, there has been an increasing concern with how wild pigs affect native species. An abundance of research on their impacts has been through the lens of damage to anthropogenic resources and plant communities. However, quantitative research on how wild pigs affect populations of native animal species is an understudied topic.

Aims

Our goal was to assess how wild pigs affect white-tailed deer (Odocoileus virginianus) at a population level by measuring changes in deer abundance as wild pigs are removed. White-tailed deer are an economically valuable game species in North America, and negative impacts of wild pigs on their populations could have trickle-down impacts on conservation funding for all wildlife.

Methods

On three treatment areas (34.07–55.31 km2) and one control area (25.10 km2), we used N-mixture models to compare data from camera-trap surveys of white-tailed deer before and after wild pigs were removed from treatment areas.

Key results

We removed 1851 pigs from the treatment sites between May 2019 and March 2021. We found that wild pigs did not significantly affect white-tailed deer abundance, but that white-tailed deer were 1.12 (1.02–1.23; 95% CL) times as likely to be detected when the number of pigs removed was equal to our baseline population estimates compared with when no pigs were removed. Although results from similar analyses on separate age and sex classes of white-tailed deer exhibited similar results, analyses of impacts on immature males differed.

Conclusions

Our overall results are congruent with those of other research that suggest that wild pigs affect white-tailed deer behaviour at a local scale, although eliminating pigs from an area does not appear to quickly lead to increased abundance of deer.

Implications

Although the interspecific interactions between white-tailed deer and wild pigs are unlikely to lead to a decline in the population of white-tailed deer, removing wild pigs may decrease the behavioural implications of these interactions.

Keywords: camera survey, density estimate, detection, interspecific interaction, invasive species, N-mixture model, white-tailed deer, wild pig.

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