Roads and other transportation infrastructure are vital to visitors and conservation managers at national wildlife refuges. They also can fragment habitat and compromise wildlife and driver safety.
Recognizing this, the U.S. Fish and Wildlife Service Transportation Program has been working with the Federal Highway Administration (FHWA) and state/local agencies to improve habitat connectivity and safety, especially in working to build wildlife culverts and fish passages under new/improved roads near refuges.
At Laguna Atascosa National Wildlife Refuge in south Texas, acting manager Leo Gustafson says data show that on average endangered ocelots cross refuge visitor roads about 45 times per month and a local state highway about four times a month. Gustafson points out that the estimated dozen ocelots at the refuge are one of only two remaining breeding populations known to occur in the United States. The other population of three dozen is on private land north of the refuge. South Texas zone biologist Mitch Sternberg says at least 20 ocelots have died in road accidents in recent decades. Conserving and connecting habitat for ocelots is critical to minimizing mortality risk and improving the species ability to flourish. In 2016, the Service and the FHWA are planning to build five ocelot crossings, two on the refuge and three on a bordering county road.
Southwest Region refuge transportation coordinator Robert OBrien hopes the crossings will demonstrate to local
and state DOTs that we are being proactive on our side of the fence, and the crossings on the refuge can serve as an example design for wildlife crossings outside the refuge on state and county roads.
At Kenai National Wildlife Refuge in Alaska, supervisory biologist John Morton says that in 2009 more than 1.4 million vehicles traveled the 22 miles of the Sterling Highway bisecting the refuge. From 2000 to 2007, Morton says, there were 174 vehicle collisions with wildlife on this road section, including 24 black bear, three brown bear, five caribou and 142 moose.
As a result, agencies are cooperating to identify the crossing hotspots. The refuge is working with Alaska DOT to develop wildlifemitigation structures as part of the states plans to improve that section of the highway as soon as funding is available.
At Silvio O. Conte National Fish and Wildlife Refuges Nulhegan Basin Division, staff members are working with the Vermont Fish and Wildlife Department and Trout Unlimited to inventory/prioritize culverts to improve fish habitat connectivity. A major rehabilitation of Lewis Pond Overlook Road this summer included three fishbearing culverts where barriers to fish passage existed previously.
At Alligator River National Wildlife Refuge, North Carolina DOT, the Services Southeast Region and refuge staff are for the first time discussing black bear and red wolf crossing issues along state routes that run through the refuge. They seek to minimize wildlife mortality.
At Great Dismal Swamp National Wildlife Refuge on the VirginiaNorth Carolina border, in 2005 a multiagency partnership resulted in two large crossing underpasses, as well as several small structures, to accommodate the passage of black bears, deer and bobcats under U.S. Route 17, which skirts the refuge. This is especially important because the refuge is at biological carrying capacity for bears, and juveniles are likely to establish territory beyond the refuges boundary. With a fourlane, divided highway that receives a lot of traffic, it is essential to have safe crossings for the bears to move east from the swamp, says refuge manager Chris Lowie.
Steve Suder, the Services national transportation program manager, says the key is federalstatelocal cooperation from the start:
As we look forward at mitigating the impact of wildlifevehicle collisions in the vicinity of national wildlife refuges, we must be proactive and collaborate with our partner agencies to achieve the many mutual benefits that result.
Jeff Mast is Refuge System transportation coordinator for the Northeast Region.