Characterizing the width of amphibian movements during postbreeding migration

Area of Science:

• Ecology
• Conservation Biology
• Wildlife Management

Background:

• Habitat fragmentation in developed landscapes threatens animal population connectivity.
• Designing effective wildlife corridors requires empirical data on animal movement patterns, specifically lateral movement width.
• Pond-breeding amphibians face challenges in maintaining population connectivity due to habitat alterations.

Purpose of the Study:

• To quantify the lateral movement width of wood frogs (Lithobates sylvaticus) and spotted salamanders (Ambystoma maculatum).
• To inform the planning and design of wildlife corridors for pond-breeding amphibians in managed forests.
• To develop a method for estimating population-level movement patterns applicable to other taxa.

Main Methods:

• Radiotracking data were collected from wood frogs and spotted salamanders in a Maine forest.
• Polar coordinates of individual locations were used to calculate movement vectors.
• A Gaussian distribution was fitted to distances from locations to the vector sum to estimate lateral movement width (50th and 95th percentiles).

Main Results:

• Spotted salamanders exhibited 50% lateral movements ≤13 m and 95% ≤39 m.
• Wood frogs showed 50% lateral movements ≤17 m and 95% ≤51 m.
• Greater distance traveled from the pond correlated with increased lateral movement in both species.

Conclusions:

• The study provides crucial data on amphibian lateral movement widths for designing effective wildlife corridors.
• The developed methodology can be applied to movement data from various species to aid habitat linkage planning.
• Findings support spatially explicit conservation efforts for amphibians in developing areas.