Abstract

Many turtle species, including Diamond-Backed Terrapins (Malaclemys terrapin), often nest shortly before and during rainstorms. We tested the hypothesis that rain can decrease the likelihood that nests will be depredated, presumably by reducing the chemical, tactile, or visual cues that predators use to locate turtle nests. We analyzed the impact of rainfall on predation rates of Diamond-Backed Terrapin nests in Jamaica Bay Wildlife Refuge, NY, USA from June–July 2016. Natural and artificial nests built on days with no rain or varying amounts of rain were monitored for 5 d after oviposition/construction. Predation rates were similar for both artificial and natural nests and decreased when nests were laid on rainy days. For artificial nests, that decrease was significant, and for natural nests the decrease was nearly significant. Predation rates on natural and artificial nests were inversely correlated with the amount of rain on the day nests were laid or constructed. These results indicate that selection may favor turtles that nest soon before or during rainfall.