Urbanization presents a challenge for managing white-tailed deer (Odocoileus virginianus) due to the constraints it imposes on traditional methods of deer population management. Specifically, hunting effectiveness can be diminished due to decreasing parcel size, loss of huntable land, shifting landowner values, and restrictive local policies. Given the potential negative outcomes of unmanaged deer populations as landscapes urbanize, our objective was to describe how deer harvest susceptibility varied along an urban to rural gradient. Specifically, we: 1) quantified harvest probabilities for deer, 2) evaluated how these probabilities varied along an urbanization gradient based on percent impervious surface, percent huntable lands, sex, and age of deer, and 3) identified how harvest susceptibility varied throughout the hunting season. From 2022-2024, we tracked 72 male and 95 female white-tailed deer in Durham County, North Carolina, along an urban-rural gradient. Using GPS data, we quantified percent impervious surface and huntable lands within each individual's calculated home range. Results indicate that males were harvested more frequently than females across the gradient, with adults (≥ 2.5 years) being more susceptible than yearlings (1.5 years). The majority of harvest occurred after the peak conception date in the study area. Additionally, harvest probability declined as urbanness increased, regardless of sex or age. These results provide insight for wildlife managers in determining when and where harvest occurs along an urban-rural gradient, and whether to adjust strategies to meet management goals in increasingly urbanized landscapes.
Urbanization is expanding throughout the globe, creating urban-rural gradients and altering wildlife communities. While some wildlife populations decline as human presence increases, others such as white-tailed deer persist in areas with transitional habitats and increased urbanization. However, densities of white-tailed deer along urban-rural gradients are poorly understood leading to gaps in population information and management despite continued deer use. We used a spatially explicit capture-recapture framework (SCR) with fecal DNA to estimate deer densities along an urban-rural gradient in Durham County, North Carolina. Sampling occurred at 356 plots across 7 sites with percent impervious surface ranging from 1% (rural) to 60% (urban), and included public and private lands with 120 participating landowners. Field collection took place in February and March 2023 over 3 weeks using a cluster sampling design. We collected 642 fecal samples resulting in 491 genotypes (≥8 microsatellite markers, 1 sex-determining marker) of 380 unique deer (252M:127F). Based on SCR estimates, sampling site densities ranged from
Rangelands are often managed for cattle production and wildlife. Understanding the effects of cattle on wildlife relative to other factors, such as precipitation, is key to effective multiuse management. We experimentally manipulated cattle management on East Foundation’s San Antonio Veijo Ranch in South Texas where white-tailed deer are not exposed to harvest or supplemental feed. We measured recruitment indices using evidence of lactation in autumn from 284 adult female deer captured from 2011-2023 and known fate survival to 12-weeks of 90 neonates monitored during 2020-2023. We characterized capture locations of adult females and birth sites of neonates based on landscape attributes, precipitation, and cattle management. We fit generalized linear mixed models predicting the lactation status (yes or no) as a function of these covariates. We fit Cox-proportional hazards models to predict mortality hazard of neonates as a function of the same predictors. We found the presence of cattle during the fawning season (June-August) reduced the probability of lactation in adult females and increased the odds of neonate mortality. We also found both recruitment indices increased strongly with spring rain and moderately with brush density. Our results demonstrate a benefit of the rotational grazing treatment, such that deer recruitment improved where cattle were absent during the fawning season. While rainfall patterns strongly influenced recruitment, manageable factors including cattle grazing and brush density offer potential approaches to manipulate deer recruitment. Our results highlight the utility of managing these factors to achieve deer recruitment objectives.
Unmanned aerial vehicles, or drones, have become increasingly important in the monitoring and management of white-tailed deer (Odocoileus virginianus) particularly when used alongside thermal imaging sensors. Thermal drones have successfully been used for fawn capture, deer density estimation, harvested deer recovery, and other management practices, and thermal drones have been found to be both accurate and precise for deer density estimation given proper flight planning. Drones as a tool for deer monitoring and management improve upon manned aircraft in terms of costs and associated risks, but thermal drones nonetheless suffer from limitations related to battery life, signal range, line of sight requirements, and sensitivity to environmental conditions among other factors. Building on our previous work evaluating the precision and accuracy of deer density estimates gathered via drones, this presentation will discuss the current state of commercially available thermal drone technology, costs and considerations associated with implementing this technology, and lessons learned from our work. We will detail recommended flight parameters, drone models, and sensors as well as the future of this technology and its integration into deer monitoring and management. This discussion provides fundamental information for wildlife managers and researchers seeking to implement this rapidly evolving technology into their own work.
