Depredation of Painted Turtle (Chrysemys picta) nests: influence of biotic, abiotic

Abstract

Understanding how predator attractants and deterrents, as well as habitat features, affect depredation of turtle nests is important because nest predators can influence the demographic structure of turtle populations. We investigated cues used by predators to locate turtle nests in three habitats (heavily shaded, moderately shaded, and unshaded). We constructed artificial turtle nests in areas used by nesting painted turtles (Chrysemys picta) and foraging predators, primarily raccoons (Procyon lotor). We also assessed the influence of olfactory cues on nest depredation using coyote and turtle urine, and turtle egg mucus. Overall, 22% of the simulated nests displayed evidence of depredation. Habitat type did not influence probability of nest depredation. Similarly, the presence of coyote and turtle urine, and turtle egg mucus, combined or individually, did not significantly alter depredation rates. Instead, predators seemed to locate simulated nests based solely on surface soil disturbance, because such disturbance significantly increased the probability of a nest being depredated. These findings provide valuable insights into the effects of surface soil disturbance on the population dynamics of nesting turtles and their predators.