Assessing changes in population abundance is important when evaluating the effectiveness of conservation and management for wildlife. However, both observational and structural uncertainty affect the reliability of abundance estimates and may limit the ability to assess temporal or spatial differences in abundance. Further, evaluating a conservation or management action on a free-ranging population presents challenges with partial controllability. Recently, wildlife managers in Michigan sought to understand whether a specific harvest regulation had the intended consequences on a white-tailed deer (Odocoileus virginianus) population. I used a camera-trap study design to evaluate the effects of an antler point restriction (APR) regulation change on a white-tailed deer population in the south-central Lower Peninsula of Michigan, USA, 2019–2022. In my first chapter, I used a subset of camera-trap data to evaluate the sensitivity of abundance estimates to alternative sampling strategies that modified sampling frequency, sampling duration, and camera distribution. Results indicated that an N-mixture model generated reasonably reliable estimates (i.e., precise and accurate), irrespective of data modifications, and that precision was sensitive to modifications. My results emphasized the importance of sampling relevant to animal activity and highlighted viable ways to improve sampling efficiency. In my second chapter, I evaluated potential population-level changes over time and space following an APR change in a before-after-control-impact design. I found weak evidence for APRs affecting the relative abundance by sex-and-age classes. In both APR and Non-APR treatment areas, I consistently observed increasing trends in Legal and Sub-legal Male deer relative abundance over time and found no evidence supporting change in Female and Fawn relative abundance.
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