Animal movement is shaped by the environment and the necessity to engage in essential activities. Animals must use urban and rural environments in different ways to meet food, cover, and reproduction needs. Urban deer present management challenges, and understanding deer movement with respect to developing landscapes is critical to inform effective deer management decisions that promote sustainable city planning. We analyzed the impact of urbanization on white-tailed deer (Odocoileus virginianus) movement by studying 107 female deer that were captured and GPS-collared along an urbanization gradient in Durham and Orange Counties, North Carolina, from 2022 to 2024. We analyzed GPS collar data recorded at 2-hour intervals during the parturition season to assess the effects of land cover, proximity to anthropogenic features (e.g., roads), and time of day on white-tailed deer movement. We used hidden Markov movement models to classify deer into latent behavioral states and applied step selection functions to evaluate how deer navigate the landscape. This approach enabled us to quantify the proportion of time deer spent in each state across the urbanization gradient and understand how anthropogenic features affect deer movement. We determined that urbanization influenced deer movement and landscape use, with differing habitat selection across the gradient. Understanding the multifaceted effects of urbanization on deer movement, habitat selection, and behavior is important to inform management actions and predict responses of deer in urbanizing landscapes.
As urban sprawl increases, white-tailed deer have become more abundant across urban landscapes leading to increased deer encounters with residential fences. Deer-fence interactions can create dangerous situations for deer, first responders, and the public if a deer fails to jump over the fence effectively and becomes entangled in or on the fence. In order to reduce deer-fence conflicts, it is necessary to first understand the biomechanical processes deer use to cross vertical barriers. We conducted deer jumping trials in which captive deer crossed over vertical barriers (i.e., welded-wire fence panels) of varying heights while being recorded by high-speed cameras. We compared biomechanical measurements between successful and unsuccessful crossing attempts including joint angles, flight arc, and deer velocity through four phases of the jump: approach, take-off, suspension, and landing. We quantified biomechanical measurements among age, sex, and weight of deer relative to barrier heights. Our first sampling group consisted of 5 adult male deer (110 – 190 lb) and 30 total crossing attempts. Among all 30 attempts, 7 were successful, 9 were failures, and 14 did not attempt to cross. Across all biomechanical measures, it appears that the angle of the deer’s back at take-off, which affects the deer’s trajectory, most influences crossing success. We are conducting similar trials with 22 adult female deer. Altering the height and visual attributes of fencing (e.g., spacing and thickness of rails) will enable us to improve deer jumping success or entirely discourage deer from jumping barriers in order to reduce deer-fence conflicts.
White-tailed deer (Odocoileus virginianus) are key hosts for zoonotic diseases due to their susceptibility to pathogens such as SARS-CoV-2 (SCV2), Lyme Disease (Borrelia burgdorferi), and highly pathogenic avian influenza. Urban environments, with their high densities of both deer and humans, amplify the potential for disease spillover. In collaboration with USDA-WS, NPS, Washington D.C. Department of Energy and Environment, Fairfax County Park Authority (VA), and Montgomery Parks (MD), the University of Maryland’s URBANxNATURE and Applied Spatial Wildlife Ecology Lab are investigating human-deer disease transmission in urban settings. Deer are being captured using drop nets and anesthetized with BAM, 2024-2026. Nasal and oral swabs, blood samples, and ticks are being collected for testing. Out of 140 deer sampled in the winter of 2023-2024, 27 individuals tested positive for SCV2. Positive samples included ten nasal and six oral PCR positives from sharpshooting events, and eight sVNT seropositive results (five wildtype, three Omicron) from live trapping. Additionally, we confirmed the first longhorned ticks (Haemaphysalis longicornis) in Washington, D.C. These findings will inform an agent-based modeling framework to predict human-deer interaction hotspots, the context of such encounters, and the associated risk of airborne zoonotic disease transmission, contributing to urban wildlife management and public health strategies.
