Behavioral Phenomena and Population Estimation of White-Tailed Deer Based on Camera Trap Data

When shaping management actions and conservation programs, it is essential to understand the population dynamics of a species. One species that sees extensive management and research effort is the white-tailed deer (Odocoileus virginianus), as it is both ecologically and recreationally important in many places. Although there are a multitude of ways to study and estimate the population dynamics of white-tailed deer, one method in particular comes with significant advantages: camera trapping.

For this study, nine camera traps were set up at deer scrapes across a private ranch in south Texas. After collecting images during the fall/winter rut of 2015, the cameras’ photos were amassed, and photographed bucks were identified based on unique antler formations. The photo data were then analyzed for a variety of purposes: (a) to determine whether bucks visit scrapes non- randomly; (b) to examine patterns in the ranges of dominant individuals; (c) to assess whether diversity indexes identify fundamental differences in the collections of bucks visiting scrapes. Finally, a novel population estimation technique was applied by adapting and applying the program EstimateS.

There were a total of 129 bucks identified over the study region. I determined that bucks did indeed visit camera sites non-randomly and that they visited certain scrapes preferentially. This might have to do with the resources available in specific areas. Additionally, I observed that particular dominant individuals have home ranges that overlap, while others are much more solitary. This suggests that the sites themselves are differentially defensible, and that whether a location is dominated has to do with both the resources it offers and its ability to be monopolized. Results of the population estimation technique suggested that there were a number of bucks that remained undetected by the cameras. Future research could work to ascertain the accuracy of the population estimations made by EstimateS.