Determining Location and Design of Cost-Effective Wildlife Crossing Structures along US-64 in North Carolina

Abstract

U.S. Highway 64 is a primary transportation route from the Outer Banks of North Carolina. The road bisects a network of federal, state, and privately managed conservation areas that provide habitat for black bear, red wolf (a federally endangered species), migratory birds, a diverse assemblage of herpetofauna, and numerous other species. The North Carolina Department of Transportation has plans to widen the highway from two to four lanes. The effects of increased habitat fragmentation and projected sea-level rise were significant concerns. Wildlife surveys were conducted from April 2009 to July 2010 to assess existing highway impacts. Roadkill and track surveys provided data on successful and unsuccessful road crossings. Roadkill data included 27,877 individuals of 113 species. From 31 track stations, 18 different species or taxa from 7,477 tracks were recorded. Spatial analysis of roadkill and track data revealed significant hot spots of wildlife activity. Results of field surveys and landscape analysis were used to determine candidate locations for wildlife crossings and other measures to reduce adverse effects of the proposed widening of the road. Recommendations included type of structure and design specifications according to site specifics and target species requirements.