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Public Roads - May/June 2005

May/June 2005
Issue No:
Vol. 68 No. 6
Publication Number:
Table of Contents

Where The Wildlife Meet The Road

by Alex Levy

Participants in a 2001 European scan tour are breaking new ground in mitigating the impacts of highways on wildlife.

The balance between humans and nature is a delicate one, and the U.S. transportation community is seeking an acceptable balance between highway infrastructure and wildlife health. In Europe, where the roads of western civilization have fragmented wildlife habitat for centuries, transportation and environmental agencies, research institutions, and nonprofit organizations have been working for years to minimize the impacts of highway infrastructure on wildlife.

This dramatic wildlife overpass is one of two located on the cross-continental Trans-Canada Highway in Alberta's Banff National Park. The innovative retrofit project used precast concrete arches and a minimal amount of equipment, thereby minimizing the impact on the traveling public.

In October 2001, an International Scanning Tour for Wildlife Habitat Connectivity across European Highways visited portions of five nations to determine which strategies might be adapted for use in the United States. The scan team included participants from the Federal Highway Administration (FHWA), American Association of State Highway and Transportation Officials (AASHTO), U.S. Department of the Interior's National Park Service (NPS), USDA Forest Service (USFS), State departments of transportation (DOTs), and two nonprofits, Defenders of Wildlife and The Humane Society of the United States.

In the 3-plus years since the scan tour, the participants have taken the insights from the scan tour and applied them in the U.S. context. Among them are new techniques, training courses and workshops, print and online resources for practitioners, policy advocacy, and on-the-ground research—efforts that are detailed in the following case studies. (For more information on the scan tour itself, see "The Scan of the Wild," PUBLIC ROADS, November/December 2002.)

An Eastern State on the Cutting Edge

One State represented on the scan tour has become a leader in the mitigation of wildlife impacts, in large part due to a fresh way of thinking. More than any specific mitigation techniques, David Scott, former director of program development for the Vermont Agency of Transportation (VTrans), returned with a shift in perspective. "The greatest revelation for me personally during the European scan was that the countries considered the inclusion of green bridges [vegetated overpasses] on projects as standard practice," says Scott. "The cost for a wildlife crossing, when developed along with the rest of a project, was estimated [by project sponsors] to have increased the total cost by only 7 or 8 percent."

Scott started by investigating the interface between transportation and wildlife habitat in Vermont. "After returning from Europe, I was convinced that the first thing we needed to accomplish was to identify areas of sustainable habitat," he says. "These were the major blocks of land protected by the State, such as the Green Mountain National Forest. Once we completed this mapping, it became extremely clear where highways create barriers between habitats."

The International Technology Scanning Program

The International Technology Scanning Program accesses and evaluates innovative foreign technologies and practices that could significantly benefit U.S. highway transportation systems. The program enables advanced technology to be adapted and put into practice more efficiently without spending scarce research funds to re-create advances already developed by other countries. The program is undertaken jointly by FHWA and AASHTO's Special Committee on International Activity Coordination, in cooperation with the Transportation Research Board's National Cooperative Highway Research Program (NCHRP) Project 20-36, Highway Research and Technology—International Information Sharing.

VTrans staff members on snowshoes are participating in "highway edge" training on the interaction between wildlife habitat and transportation facilities along the VT 289/Chittenden County Circumferential Highway.


VTrans staff members observe mink and otter tracks in a wildlife crossing structure near the VT 289/Chittenden County Circumferential Highway.

This effort grew into a joint VTrans and Vermont Fish and Wildlife Department (VFWD) project, culminating in a geographic information system (GIS) database that integrates all State data on conservation lands, habitat, and roadkill. When the database is completed, VTrans staff will be able to turn on a "habitat layer" in an Environmental Systems Research Institute, Inc. (ESRI) ArcViewª software program and obtain information on, for example, the number of bears in a region. Both planning and rehabilitation efforts will benefit from a clear picture of where efforts should be made to preserve linkage areas and enhance protected habitat. VTrans and its partners also have worked to institutionalize the ongoing collection of these data to track progress over time.

Another new initiative that Scott started was an 8-day course, spread over several weeks, to train transportation staff about the habitat needs of wildlife. Leaders of the course are Susan Morse, founder of a local wildlife habitat nonprofit called Keeping Track, and Jim Andrews, a research herpetologist at Middlebury College. Initially only environmental staff participated, but as demand grew, planners, engineers, and maintenance staff began taking part. After a round of classroom lectures and meetings with regulators, participants make field visits to better understand the habitat needs of animals ranging from small amphibians to large mammals.

The VTrans staff members walk through pristine areas and along roadways to learn how the transportation system can disrupt wildlife habitat. One assignment is to go out on a rainy night to see nocturnal animals crossing the roads. According to Chris Slesar, an environmental specialist in the VTrans program development and environment section and former course participant, "When people realize that they've been driving over wood frogs and mole salamanders, not leaves, they drive really carefully next time."

During a spring session of the habitat training, VTrans staff members examine a amphibian egg mass near a vernal pool.

The program is successful on a number of fronts. Slesar notes, "So many people who work here really love the outdoors, and they get very interested in finding out how they can do their jobs in a way that helps the environment."

Small changes are already starting to happen. In one instance, designers installed a vertical retaining wall instead of a slope leading to a wetland, to prevent animals from climbing up to the road and possibly becoming roadkill. In another, a repaving project at Green Mountain included bear crossing signs.

Scott is pleased with the overall impact. "Learning about habitat has been a real eye-opener for the staff and has helped to improve our image and working relationship with our counterparts at Fish and Wildlife."

Jim Andrews (far left), a research herpetologist from Middlebury College, and another instructor discuss a black rat snake held by Lilla Lumbra of the Vermont Fish and Wildlife Department.

Besides the long-term changes, the scan tour also helped solve some immediate problems. In 2001, VTrans and State and Federal resource agencies were participating in monthly facilitated sessions about how to reconstruct 9.7 kilometers (6 miles) of Vermont Route 78, a significant portion of which passes through the Missisquoi National Wildlife Refuge and its 2,673 hectares (6,600 acres) of pristine wetlands. Upon Scott's return from Europe, he championed the construction of a roadway containing numerous dry culverts and concrete boxes to allow smaller mammals to cross the roadway and a 3-meter (10-foot)-high, 153-meter (500-foot)-long dry-span bridge for larger mammals. The resulting agreement moved the project forward with support from all the resource agencies.

A red eft—one stage in the life cycle of a newt common in the East—is crossing this Vermont road. One challenge is protecting species like this that are not federally protected.

Finally, VTrans' leadership is being shared with other States. At the 2003 International Conference on Ecology & Transportation (ICOET), VTrans participants talked with other New Englanders about how to improve cooperation on regional wildlife issues, especially those not involving regulated species. The result was the Northeast Transportation and Wildlife Conference in September 2004. Cosponsored by FHWA, VTrans, VFWD, and the nonprofit National Wildlife Federation, the workshop started a broad conversation on integrating regional planning on transportation and wildlife conservation. Representatives from Maine, New Hampshire, and Vermont staffed the panels, and the conference attracted 125 participants. The current goal is to hold the meeting every other year.

A Western State Also Takes the Lead

Moving across the country, another successful conference with a scan team connection was Arizona's Missing Linkages Workshop in April 2004. The steering committee for the conference included representatives from the Arizona Department of Transportation (ADOT), FHWA, U.S. Fish and Wildlife Service (USFWS), Arizona Game and Fish Department (AZGFD), U.S. Department of the Interior's Bureau of Land Management (BLM), Tonto National Forest, and Northern Arizona University. Steve Thomas, environmental program manager with the FHWA Arizona Division, describes the steering committee as "a room full of passionate people" interested in changing Arizona's approach to wildlife impact mitigation. The workshop, held at the Phoenix Zoo and attended by more than 100 biologists and planners, began identifying 80 present and future habitat connectivity needs (the "missing linkages"). Scan team member Bill Ruediger, ecology program leader for highways with USFS (since retired), helped stimulate the interagency dialogue that resulted in the workshop and was one of the speakers.

This GIS-produced map shows the location of wildlife crossings and habitat in north-central Vermont along U.S. 89.


International Conference on Ecology and Transportation

The Center for Transportation and the Environment administers the International Conference on Ecology and Transportation (ICOET), with the support of FHWA and several other Federal and State agencies and organizations as sponsors. Held every 2 years, ICOET addresses a broad range of ecological issues related to surface transportation and highlights current research findings and best practices in the areas of wildlife, fisheries, wetlands, water quality, overall ecosystems management, and related policy issues. ICOET is a multidisciplinary event supported by a number of agencies. The ICOET conference in San Diego, CA, from August 29 through September 2, 2005, will be cohosted by the California Department of Transportation in cooperation with the Road Ecology Center at the University of California, Davis Institute of Transportation Studies. For more information, visit

The workshop had two lasting outcomes. First was the creation of a preliminary statewide linkage map, which was refined at six ecoregional workshops in November 2004. The GIS-based map includes layers for vegetation types, riparian habitat, watercourses, land use, and roads. When the preliminary map is finished in spring 2005, the data will undergo field testing. Once completed, the map will enable transportation and wildlife specialists to incorporate wildlife habitat protection into highway planning, construction, and maintenance. Ultimately the map will be integrated into transportation projects, land use plans, conservation plans, and the State's Comprehensive Wildlife Strategy.

The workshop's second outcome is the development of solid working relationships among the agencies that participated in the meeting. As FHWA's Thomas puts it, "Building trust is a day-to-day thing; it continues to grow and develop. Over time we are building up these relationships, so that when we work on projects together, we trust that the other person will do what they say." Agencies not previously involved now routinely collaborate on projects.

Norris Dodd and Ray Schweinsburg of the Arizona Game and Fish Department fit an elk with a radio collar that will track the animal's movement for several weeks. The data can show where the animal has traveled and whether it used a highway underpass.

Like Vermont, Arizona has changed its collective attitude regarding the mitigation of wildlife impacts. During widening of State Route 260, deer and elk crossings were incorporated toward the end of the process, after the environmental impact statement was already complete. Thomas says, "People thought, 'What a shame that it was almost in final design before linkages and connectivity issues were brought to the table.'"

Because the project was successful—FHWA named it one of three Exemplary Ecosystem Initiatives in 2003—Arizona has sought to incorporate wildlife issues earlier in the National Environmental Policy Act process. As part of a plan to widen U.S. 93 approaching Hoover Dam, AZGFD (with FHWA and ADOT funding) placed collars on 30 bighorn sheep to study their migration patterns. The highway will be designed to mitigate impacts on the bighorn habitat, adding crossings where the sheep usually travel. The rest of the 27-kilometer (17-mile) highway will be fenced off to prevent the animals from wandering into traffic. "This is one of the largest and most important herds of bighorn sheep in the western United States," says Thomas, "so it's important to protect them." Arizona DOT has identified approximately $6 million out of $58.9 million in total project funding to offset impacts on the bighorn sheep.

Second Nature, a report coauthored by Trisha White of Defenders of Wildlife, recommends installing wildlife crossings like this culvert in Banff National Park of Canada that permits deer, small carnivores, frogs, and snakes to pass under the road.

Syntheses and Guidance Documents

The scan tour also led to several reports that share team members' observations with other transportation professionals. In late 2002, scan facilitator and retired Florida DOT biologist Gary Evink wrote the National Cooperative Highway Research Program (NCHRP) Synthesis 305: Interaction Between Roadways and Wildlife Ecology. The assessment discusses the relationship between North American wildlife ecology and roadways, identifying a suite of best practices and case histories. Among the case studies is the author's firsthand experience with one of the Nation's most celebrated wildlife crossings, which enables endangered Florida panthers to travel beneath a highway that crosses the Everglades.

Members of the scan team have presented the findings detailed in Evink's synthesis at numerous conferences, including the annual meeting of the Transportation Association of Canada, the biennial meeting of the Infra Eco Network Europe, the Alabama Transportation Conference, Kansas Transportation Engineering Conference, the 2003 FHWA Southern Environmental Leadership Summit, and the 2004 National Association of Environmental Professionals' Annual Conference.

Encouraged by the success of applying context-sensitive solutions to address cultural and natural resource values, FHWA Montana Division scan team member Dale Paulson (retired from FHWA) and Montana Division Administrator Janice Brown, along with representatives from other Federal agencies, are developing a Wildlife and Habitat Handbook for Federal, State, and local partners involved in infrastructure planning, design, review, and construction. The focus of the handbook is ecosystem planning. To quote from the draft handbook, "When we administer regulations on a project-by-project basis, we often miss opportunities for substantive contributions to species, watershed, and ecosystem restoration and recovery. Using an ecosystem approach, we can be positioned to seize opportunities to pursue the intent of environmental regulations outside the realm of a specific project."

Or as Paulson puts it, "We saw the Europeans taking a broader approach, so we started looking at doing the mitigation where it makes the most sense, not just at the project site."

The other agencies involved in developing the handbook, which is facilitated by the U.S. Department of Transportation's Volpe National Transportation Systems Center, include the U.S. Environmental Protection Agency, U.S. Army Corps of Engineers, USFWS, BLM, NPS, USFS, National Oceanic and Atmospheric Administration, and State DOTs. Once complete, the handbook will outline a collaborative, comprehensive approach to address the highest priority needs in an ecological region. This framework will describe key ingredients, tools, techniques, and resources to enable Federal, State, and local users and nonprofit organizations to work in partnership to initiate integrated planning and deploy creative approaches to mitigate ecological impacts. The steering committee anticipates completion of the handbook in early fall of 2005.

Wooden beams atop this wire right-of-way along Wyoming 135, southeast of Riverton, help deer judge the fence's height so that they can clear it if they jump, rather than tripping and getting injured.

Influencing Policy

One of the scan team members, Trisha White of Defenders of Wildlife, credits her experience on the trip with providing valuable perspective on her current position as director of the organization's Habitat and Highways Campaign ( "When we were in Europe," she
says, "we saw so many examples of 'strange bedfellows'—hunters working with biologists, farmers working with transportation agencies, and nongovernmental organizations [NGOs] working with government." Likewise, she adds, the friendships that she made during the scan tour are invaluable, including staff from State and Federal agencies. "There is a tight bond among the network of people working on this issue, and we all lean on each other to make any progress," she says.

White coauthored a report, Second Nature: Improving Transportation Without Putting Nature Second, which received a "best publication" award from the Natural Resources Council of America (NRCA) in 2004. NRCA recognized the report for its groundbreaking and influential approaches to reducing the impact that roads and highways have on wildlife and habitat. Second Nature, released in April 2003 as a joint project of Defenders of Wildlife and the Surface Transportation Policy Project, outlines realistic, workable recommendations that factor in growth while protecting wildlife and their habitat. The report has had significant influence on policy. White says that one DOT used it while drafting a long-term plan and another as a textbook for the agency's field courses.

Scan team member Susan Hagood of The Humane Society of the United States (HSUS) worked with Congress to emphasize the need for States to consider wildlife-crossing measures in their long-range transportation and resource management planning processes. As Hagood put it, "We looked to Congress to emphasize wildlife-sensitive roadways not just for wildlife, but for public safety as well, since they are equally important issues."

To help communicate its message, HSUS produced an 11-minute video called "The European Connection: Designing Roads with Wildlife in Mind," which includes footage taken on the scan tour and from projects in North America (including Vermont Route 78, discussed earlier). Hagood estimates that HSUS and FHWA have distributed 1,000 copies of the video, which includes the FHWA logo. Uses of the video include a Washington State nonprofit's outreach campaign supporting wildlife crossings on I–90.

Ongoing Research

Hagood's contributions to wildlife extend beyond advocacy to basic research. With financial support from FHWA, Hagood is conducting research for her Ph.D. dissertation on the impact of roads on the population genetics of the Eastern box turtle, a species that is especially sensitive to habitat fragmentation. As she explains, "They're often compared to grizzly bears—they take a long time to mature, and each adult produces very few young throughout its lifetime, as egg and hatchling mortality is high, so the loss of adult turtles can be devastating. And they're vulnerable to the impacts of roads, since the turtles move slowly and females need to travel to find egg-laying sites."

Hagood's research compares seven study sites in the Washington, DC, metropolitan area—two relatively large undisturbed areas and five surrounded by extensive development. Over 3.5 years, she will compare the genetic structure of the seven turtle populations to determine whether those in the developed areas show signs of inbreeding. The results will be used to inform management decisions for this declining reptile, including evaluating the need for structures that could improve safety for area box turtle populations.

FHWA also is underwriting significant research at the Western Transportation Institute at Montana State University-Bozeman to develop a report, Guidelines For Designing and Evaluating North American Wildlife Crossing Systems. Due out in 2005, the guidelines are expected to be the first comprehensive compendium of best practices and current technologies. A similar topic is under study in an ongoing 3-year NCHRP research project led by Utah State University: Evaluation of the Use and Effectiveness of Wildlife Crossings.

Virtual Wildlife Conservation

Several Web sites helped chronicle the scan tour and create practical tools available in the public domain. FHWA's "Keeping it Simple: Easy Ways to Help Wildlife Along Roads" ( is a smorgasbord of best practices for roadside wildlife conservation. Created by FHWA's Office of Natural and Human Environment, "Keeping it Simple" maintains an active database that highlights ways to reduce highway impacts on wildlife. Divided into four categories roads, bridges, waterways, and wetlands/uplands—the practices span Wyoming, where wooden beams make a wire fence easily visible to deer; a boardwalk at Orange Beach, AL, that keeps beach visitors from trampling the habitat of an endangered mouse; and signs in Georgia informing construction and maintenance crews about environmentally sensitive areas. The site currently features more than 130 examples from all 50 States and continues to add new success stories.

The "Wildlife Crossings Toolkit" at helps professional wildlife biologists and engineers who face challenges integrating highway infrastructure and wildlife resources. The Web site provides a searchable database of case histories of mitigation measures, articles on lowering wildlife highway mortality, and ways to increase animals' ability to cross highway corridors. The USFS San Dimas Technology & Development Center initiated the project, while the Web site was created by Utah State University's Jack H. Berryman Institute with support from the S.J. and Jesse E. Quinney Foundation. Other partners include the Western Transportation Institute and FHWA, which funded the addition of a major section on European solutions to highway/wildlife interactions based on the 2001 scan tour.

The Center for Transportation and the Environment at North Carolina State University's Institute for Transportation Research and Education created the "Wildlife Fisheries and Transportation Web Gateway" ( The gateway provides transportation agencies and their partners with access to information about current research, best practices, policy issues, and training opportunities on the relationship between surface transportation development and wildlife and fisheries ecology. Included is a bibliography of publications collected during the 2001 scan tour.

In Georgia, GDOT installs signs like this one to inform construction and maintenance crews that they are working in an environmentally sensitive area (ESA).

The Big Picture

The scan tour participants brought back from their European counterparts a wealth of observations and ideas on wildlife issues fully incorporated into transportation projects. The work they are doing nearly 4 years later suggests that such integration is possible in an American context. Some important themes include understanding of habitat issues, early integration of wildlife impact mitigation into project planning, tools for mapping habitat, managerial support, interagency cooperation, and sharing of success stories. The scan tour helped boost efforts to ensure a safe and efficient transportation system for both two- and four-legged stakeholders.

Alex Levy served as an environmental protection specialist in FHWA's Resource Center from 2000 to 2004. In fall 2004, he left his native Atlanta to become the newest senior ecologist at FHWA headquarters. Levy brings more than a decade of experience in the public and private sectors conducting field studies and coordinating ecological assessments and impact permitting for transportation, utility, and site development projects. With a bachelor's degree in landscape architecture from the University of Georgia, he promotes cooperative project evaluation and resource conservation planning that result in better decisionmaking and context sensitivity for integrating the built and natural environments. Levy works with FHWA staff, State DOTs, and resource agencies as they improve the public's investment in the environmental quality of existing and future surface transportation.

For more information, contact Alex Levy at 202–366–1862 or