Hot moments and hot spots: Identifying factors explaining temporal and spatial variation in turtle road mortality

Many conservation strategies focus on reducing the risk of road mortality. Turtles, which are highly susceptible to road mortality, exhibit life history traits that increase their vulnerability to population declines because of road mortality. Here, we use Akaike's Information Criterion to identify road mortality hot moments and hot spots for 5 turtle species (Chelydra serpentina, Pseudemys concinna, Terrapene carolina, Terrapene ornata, and Trachemys scripta). We tested 2 hypotheses: 1) Hot moments coincide with the breeding season of each species and 2) hot spots are associated with the habitat where each species is most commonly observed. As predicted, breeding season (May–Jun) explained most of the temporal variation in road mortality for all 5 species. Over 98% of all observed road mortality occurred during this 2-month span. For C. serpentina and T. ornata, spatial variation in road mortality was best explained by the distance to the nearest water body, whereas distance to the nearest forest was the best model for T. scripta. The null model ranked best for P. concinna and T. carolina, suggesting none of our spatial models sufficiently explained mortality patterns of these 2 species. These results, coupled with previous studies, suggest that hot moments may be consistently associated with the breeding season. However, hot spots may be species-specific, requiring conservation efforts to be targeted at certain species. © 2012 The Wildlife Society.