Habitat type and distance to edge affect movement behavior of juvenile pond‐breeding salamanders

Abstract

AbstractBehavioral strategies of natal dispersers in response to human‐altered habitat have far‐reaching implications for functional connectivity and local population dynamics. Spotted salamanders Ambystoma maculatum are forest‐dependent, pond‐breeding amphibians which metamorphose and disperse out of aquatic habitat with limited knowledge of the terrestrial habitat. We quantified the fine‐scale movement behavior and search strategies of recently metamorphosed spotted salamanders in three different habitat types (field, early successional forest and forest) and at varying distances from both hard (field and forest) and soft (early successional forest and forest) edges using fluorescent powder tracking. We found that salamanders moved straighter and with fewer turns through field habitat compared with both forest and early successional habitat. Salamanders significantly oriented movement toward forest when released in the field and when released on the edge between the forest and field. We found that salamander movement in the forest and early successional forest was approximated by a correlated random walk. Based on these results, dispersing spotted salamanders exhibit strong edge‐mediated behavior when differences between habitats are stark (forest and field) and can perceive forest habitat from distances of at least 10 m. These results indicate that dispersing juvenile salamanders exhibit reasonable behavioral rules when moving through habitat types of differing quality. Knowledge of these behavioral rules will improve predictions of the effects of habitat type and configuration on amphibian survival and dispersion in altered landscapes.