The Evolution of Wildlife Exclusion Systems on Highways in British Columbia
Since the mid-1980’s, the British Columbia Ministry of Transportation (BCMoT) has been addressing the issue of motor vehicle-related wildlife collisions on Provincial highways with engineered wildlife exclusion systems. As a result of this initiative, the British Columbia has one of the most extensive networks of wildlife exclusion systems, designed to reduce and prevent motor-vehicle-related mortality of terrestrial mammals, in North America. Typically, wildlife exclusion systems are incorporated as an integral part of new highway development after the potential of wildlife mortality has been identified during highway planning stages. The systems are designed to protect wildlife from motor vehicles and ensure wildlife habitat connectivity. They have been constructed primarily on limited-access, high-speed highways and expressways and designed to protect specific species of wildlife, primarily large ungulates, such as deer, elk, moose and mountain sheep. The systems comprise of specialized fencing and related structures, such as one-way gates, ungulate guards, and crossing structures, designed to safely and effectively protect wildlife by recognizing species-specific behavioral, physical and anatomical characteristics. To date, BCMoT has installed over 470 km of wildlife fencing, incorporating over 100 crossing structures and hundreds of one-way gates. While the wildlife exclusion systems have been shown to reduce the potential for motor vehicle-related wildlife mortality, BCMoT is continually reviewing the designs of the components of these systems in an ongoing effort to improve them. With each successive project, as the interactions of wildlife with these systems become better understood, BCMoT has refined its fence and crossing structure designs and standards to increase their efficiency, effectiveness and safety for wildlife. BCMoT has also focused its attention on material quality, manufacturing processes and construction techniques to offset the challenges of climate, topography, vegetation and human activity to maximize the effective functional lifespans of wildlife exclusion systems.