Amphibian Movements in Response to Forest Edges, Roads, and Streambeds in Southern New England

Abstract

If management of landscape linkages is to be promoted as a means of conserving amphibian populations, it must be demonstrated that amphibian dispersal does not occur independently of ecosystem edges and other salient landscape features. I used drift fences and pitfall traps to intercept dispersing amphibians and examine amphibian movements relative to roads, forest edges, and streambeds in a forest tract in southern Connecticut. Capture rates of 3 species (marbled salamander, Ambystoma opacum; red-spotted newt, Notophthalmus viridescens; pickerel frog, Rana palustris) were influenced by forest borders and streambeds, whereas captures of 3 other species (spotted salamander, Ambystoma maculatum; redback salamander, Pleth-odon cinereus; wood frog, R. sylvatica) were not. Across all species, the relative permeability of forest-road edges was much reduced in comparison to the forest interior and to edges between forest and open land. The data suggest that landscape-level conservation strategies aimed at amphibians should account for such filters and conduits to amphibian movement.