Purposeful wanderings: Mate search strategies of male white-tailed deer

Abstract

In species where defense of females or resources attractive to females is not an option, males search for mates. How males locate mates is not well understood. Male white-tailed deer (Odocoileus virginianus) are assumed to search widely for females in estrus; but the rut (2-4 weeks) and estrus (1-2 days) are short and males would benefit by having a strategy to locate mates. Because females typically have small home-range sizes and exhibit site fidelity, we predicted males would spend time in small focal areas containing females during rut. We fitted 102 males with GPS collars across 5 breeding seasons in South Texas. During rut, movement rates increased but most males used a small portion (26-34%) of their home ranges. Most males had ≥ 2 small focal areas (18-33 ha) which were revisited every 20-28 h. Because estrus is ∼24 h, males may revisit focal areas to assess female receptiveness. During peak rut, 1 year olds had the lowest movement rates and rates were similar in 2- and ≥ 3-year-old males. However, most 2 year-old males exhibited Levy walks, an efficient search strategy when resources are rare. One-year-old males may not have exerted high effort, whereas most 2 year olds used a different strategy because of competition or lack of experience. Our results provide the first fine-scale description of ungulate mate-searching behavior and how spatial memory may be important for acquiring mating opportunities in species that rove for mates.