Predator community and human recreation at a Spotted Turtle (Clemmys guttata) nesting site

Résumé

Many freshwater turtle populations experience high nest depredation, resulting in low recruitment, and are subject to high
levels of human disturbance, which can influence behaviour. Spotted Turtle (Clemmys guttata) is a declining freshwater species and little is known about potential nest predators and human recreation pressures at nest sites. In 2021 and 2022, we identified 18 Spotted Turtle nests at a powerline right-of-way in Bristol County, Massachusetts, and monitored them with camera traps until hatchlings emerged. We identified all potential predator species and human recreation activities detected in images. We assessed predator behaviour using a behaviour ratio that we calculated as the quotient of number of predator “investigating nests” events and total events for each predator species pooled among all nests. We compared behaviour ratios among species. We characterized all human recreation activities at each nest and calculated diversity and the number of events for each recreation type. We detected six potential predator species and five types of human recreation activities at nest sites. Coyote (Canis latrans) was the most frequently detected potential predator but had a very low behaviour ratio (0.03). Raccoon (Procyon lotor) had the highest behaviour ratio (0.39) and was significantly more likely to investigate nests than other potential predators. Raccoon nest investigation rates did not vary by macrohabitat type or distance to edge. Our study reveals a broad look into the potential predators of Spotted Turtle nests, documents human recreation occurring at nest sites, and has several implications for nest site management.