Research during my graduate studies has mostly focused on three ecological topics:
1) Reproduction and mating systems. In many biological systems, individuals strongly compete for access to a limited number of potential mates, and therefore sexual selection is a primary selective force shaping organismal phenotypes. For my dissertation research, I used quantification of space use and observations of male-female interactions to characterize the mating system of the speckled rattlesnake (Crotalus mitchellii). My study demonstrates that sexual selection seemingly acts on two different male phenotypic traits: investments in mate-searching activities (which increase female encounter rate) and male body size (because larger males are more likely to acquire and defend a female partner against other males).
2) Foraging ecology. Diet and foraging tactics are among the central concerns of behavioral and evolutionary ecology, and are relevant to an understanding of habitat use, activity patterns, and life history evolution. As part of my dissertation research, I investigated the relationship between space use and food distribution at two spatial scales in an ambush predator, the speckled rattlesnake. My research demonstrates that at the home range level these snakes selected the habitats where rodents were the most abundant. In contrast, the specific foraging locations selected by the snakes within their home range (i.e., the microhabitats) were characterized by relatively low rodent abundance, compared to random locations, seemingly because rodents exhibited behaviors that decreased predation risk at the microhabitat level. I used the results of this study to emphasize the challenges that ambush predators may experience when foraging for risk-sensitive prey, and the energetic implications of the “sit-and-wait” foraging strategy used by ambush predators.
3) Antipredator behavior. Venomous snakes are responsible for 30,000 to 40,000 human deaths worldwide per year. For my master’s degree, I studied several aspects of the antipredator behavior of two species of North American venomous snakes, the cottonmouth (Agkistrodon piscivorus) and the pygmy rattlesnake (Sistrurus miliarius), toward humans in the field and laboratory. The main findings of my studies are that venomous snakes are not simple “automatons”, because they make context-dependent sophisticated decisions when confronted by potential predators; and that snakes that use warning displays are subsequently more likely to strike at a potential predator, suggesting that snake warning behaviors may provide an honest signal about the snake’s disposition to would-be predators. Collectively, my master’s research contributed to a better understanding of the defensive responses of viperid snakes (the group of snakes that comprises vipers, rattlesnakes and allies) toward humans, an ironically understudied aspect of venomous snake biology.