This report presents information on research conducted along US 64 from the City of Columbia east to the Alligator River in Tyrrell County, NC. The products of the study include a literature review, evaluation of habitat use and wildlife movement patterns, recommendations for need and locations of cost-effective wildlife crossing structures, and recommendations for additional cost effective design and construction measures to minimize adverse impacts to wildlife and increase highway safety.
The need for wildlife crossing structures or other measures (to improve habitat connectivity and permeability of US 64 for wildlife) was evaluated by monitoring successful and unsuccessful (road-kills) animal movements across the highway. Multiple methods were applied to evaluate activity by different species adjacent to the highway. For instance, remotely operated cameras and tracking stations are effective in capturing presence of medium to large species, and drift fences/pitfall traps are effective in determining presence-absence of small mammals and herpetofauna. Trapping studies were important in determining potential avoidance by certain species to the road right-of-way.
We performed road-kill surveys on the 13 mi segment of US 64. Track monitoring was conducted on 31 tracking strips placed at key locations adjacent to the highway. Mark-recapture studies were performed at four control locations in adjacent wildlife resource areas and at seven locations on the road right-of-way. Data was collected from April 2009 to July 2011. From all field surveys we documented 134 different species. This included 8 state and federally listed species and 16 other species of conservation interest. Data included a total of 27,886 roadkills and 7,557 tracks. Results of mark-recapture studies of small mammals and herpetofauna included 1,265 individuals along the roadside and 534 individuals at control locations.
The most recent road-killed red wolf was from 2001. More recently, a radio-collared female was documented crossing US 64 several times and tracks of red wolf were documented at several locations. Several black bear road-kills have been recorded over the last decade and track and photographs documented black bear road crossings at several locations. In addition, other carnivores were recorded making successful and unsuccessful road crossings. Few white-tail deer were observed or found as road-kill during this study; however vehicle accident reports provided 10 years' worth of data on deer-vehicle accident locations. In addition, deer tracks and photographs provided evidence of locations frequented by deer. Large numbers of road-killed frogs, snakes and turtles were recorded throughout the project area, but especially adjacent to forested wetland and marsh impoundment habitat areas. A wide diversity of avian species was also negatively affected by vehicle strikes. Most can be reduced by using appropriate fencing to reduce the amount of prey species killed on road-sides and altering flight trajectories into traffic.
Detailed results including identification of road-kill hotspots and species presence/absence are presented; proposed corrective measures including types and locations for wildlife crossing structures are discussed.
