Design Guidance for Wetland-Road Crossings to Reduce Blanding’s Turtle Mortality Risk

Creative Commons License

This work is licensed under a Creative Commons Attribution-Share Alike 3.0 License.

Authors

Thomas P. Ballestero, University of New Hampshire - Main CampusFollow
Lauren E. White, University of New Hampshire - Main CampusFollow
Sandra Houghton, New Hampshire Fish and GameFollow
David Burdick, University of New Hampshire - Main CampusFollow
Josh Megyesy, New Hampshire Fish and GameFollow

Abstract

Road mortality is a leading threat to freshwater turtles, particularly the Blanding’s turtle (Emydoidea blandingii), an endangered species in New Hampshire. Wildlife wetland-crossing structures, such as culverts and/or fences, have proven effective in reducing wildlife road mortality while retaining habitat connectivity. Funding for adequate wetland-crossing creation or restoration is limited, so prioritizing areas of high mortality risk is essential to ensuring that the resources spent are impactful. A research team of professionals from the New Hampshire Department of Environmental Services, New Hampshire Fish and Game, University of New Hampshire, and other organizations formed to create a model capable of providing a relative ranking for any wetland-crossing structure. This rubric focused on crossings in the New Hampshire Blanding’s turtle priority conservation zone based on associated freshwater turtle road mortality risk. Additionally, this group gathered information from literature reviews and case studies to create a design guidance document to be used when creating engineering plans for effective turtle wetland-crossing structures. With a guide on how to use the ranking model and an examination of wetland-crossing structure and site characteristics such as fencing, structure dimensions, lighting, and more, this document provides applicable resources to support restoration of high turtle road mortality sites to promote conservation of Blanding’s turtles and other freshwater turtles in New Hampshire.

Department

Department of Civil and Environmental Engineering

Publication Date

11-2023

Grant/Award Number and Agency

No. 00A01007 from US EPA Regional Wetland Program Development Grant under CFDA# 66.461

Language

English

Document Type

Report

Recommended Citation

Ballestero, T., White, L., Houghton, S., Burdick, D., and Megyesy, J. 2023. Design Guidance for Wetland-Road Crossings to Reduce Blanding’s Turtle Mortality Risk. Final Report to New Hampshire Department of Environmental Services and the US EPA Regional Wetland Program. pp 29 plus Appendices.