AUTHORS: Jamie Goethlich, University of Wisconsin-Madison; Tim Van Deelen, University of Wisconsin-Madison
ABSTRACT: The basis of white-tailed deer (Odocoileus virginianus) management has traditionally focused on population size, which is important for establishing harvest goals for broad-scale deer management efforts. While population estimates are important for determining the number of individuals to harvest to reduce, maintain, or increase populations, population size does not provide detailed information on the health of the population. However, herd health is a major consideration for many contemporary deer management situations, and deer health is a common concern among deer managers, deer hunters, and people opposed to deer hunting. Although health and welfare are commonly used in the livestock industry and captive wildlife settings, animal welfare is an emerging segment of wildlife research. Recently, Smiley et al. (2020) created a technique to assess body condition using photographs of captured deer, which they validated by comparing body scores to ingesta-free body fat. We tested the efficacy of pairing their visual body condition estimation method with trail camera photos of deer in suburbs of the Northeast. We found that trail camera photos could easily be used for assessing body condition, and body condition scores were generally consistent among two independent observers. Additionally, we found body condition scores varied significantly across seasons, among sexes, and between does with and without fawns at heel. Lastly, we created a detailed training pamphlet to be used as a guide for researchers and citizen scientists. We conclude that this is a quick and easy method that can be useful in situations where deer managers want information about herd health/welfare but attaining robust sample sizes of harvested deer may be unattainable (e.g., unhunted urban populations, small private properties, etc.).
