Landscape composition weakly affects home range size in Blanding's turtles (Emydoidea blandingii)

Abstract

Landscape composition and habitat quality influence the abundance, population structure, and movements of animals. Understanding how an animal interacts with elements of the landscape helps predict its response to habitat loss and changes in land cover. We tested the hypothesis that the extent of movement depends on landscape composition in a threatened freshwater turtle, Emydoidea blandingii We measured habitat composition at multiple spatial scales, ranging from the home range to the landscape scale. We built multiple linear regression models to predict home range size from the proportional use of 5 land-use categories, while controlling for intrinsic factors (sex, body size). We found that landscape composition significantly influenced home range size in the Blanding's turtle; however, the models explained a low proportion of the observed variation in home range size, meaning that landscape composition had a weak effect on movement. Our results also suggest that sex and body size have little influence on home range size in Blanding's turtles. More research is needed to determine the factors driving movement in this species, and overall, we recommend cautious use of models predicting space use as a function of landscape composition in a conservation context.