An exploration of the high cost of wildlife-vehicle collisions and the
many challenges to transforming the U.S. road network.
Documentation of the safety, ecological, economic, and social benefits
anticipated to accrue from investing in highway crossings for wildlife,
including enhanced motorist safety, reduced wildlife mortality, and improved
Identification of policy and funding improvements and activities that
would further support the deployment of crossing structures.
Recommendations on how to build upon successful efforts to reduce
wildlife-vehicle collisions already underway at the federal, state, local, and
WTI Road Ecology Program Rob Ament served as one of the editors for the report, and WTI Research Scientists Tony Clevenger, Marcel Huijser, and Angela Kociolek are contributing authors.
CITATION: Ament, R.; Jacobson, S;
Callahan, R.; Brocki, M., eds. 2021. Highway crossing structures for wildlife:
opportunities for improving driver and animal safety. Gen. Tech. Rep.
PSW-GTR-271. Albany, CA: U.S. Department of Agriculture, Forest Service,
Pacific Southwest Research Station. 51 p.
Stormwater Magazine recently interviewed WTI Road Ecologist Rob Ament on advancements in the use of environmentally friendly products for erosion control. “Saving Mowers and Wildlife” highlights state departments of transportation that are working to replace plastic netting used on roadsides with flexible, biodegradable options. In the article, state DOTs report benefits such as reduced need for removal and disposal of nets, less risk of water contamination, and fewer animals becoming entangled. Ament discusses his research on wool erosion control blankets, which are created from waste wool not suitable for clothing or blanket production. The wool erosion blankets release nitrogen into the soil as they decompose and are showing promising results related to fertilization of the sites where they are used.
WTI recently completed a feasibility study for a “Smart” transit hub to serve an eight-county rural region in western Arkansas and eastern Oklahoma. The study presents a menu of technologies and programs that help connect people experiencing transportation barriers in rural communities to healthcare, employment, and higher education opportunities.
WTI’s Small Urban, Rural and Tribal Center on Mobility (SURTCOM) conducted the project in partnership with the National Association of Development Organizations (NADO) Research Foundation, Western Arkansas Planning and Development District, and Frontier Metropolitan Planning Organization (MPO). NADO and WTI have been collaborating on a series of projects that assist rural communities with passenger transportation projects that enhance mobility options for residents.
“A traditional transit hub is a physical location where travelers can access multiple services in one place,” said Principal Investigator Rebecca Gleason; “while physical hubs are not always viable in rural areas, regional coordination and emerging technologies offer new ways to connect people to transportation information and services.” The study findings, which are highlighted in a newly released Executive Summary, include recommendations that can be implemented over time, such as hiring a regional mobility manager, exploring methods to connect more people with rides on existing systems, creating a 5-year transit development plan, and piloting a new transportation program. The Executive Summary and full study are available on the project page of the WTI website.
Roads can be dangerous for California’s reptiles and amphibians, but a five-year study and new video show that there are effective strategies to help these animals cross roads safely.
The California Department of Transportation (Caltrans) released the results of the study this week in a comprehensive, evidence-based best practices guide that explains approaches and techniques for minimizing the impact of roads on fragile and diminishing habitats and species, including frogs, toads, salamanders, turtles, lizards and snakes.
practices guide is the first of its kind for amphibian and reptile management
and conservation near California roads.
“It is no
longer a case of putting a few pipes and fences into the ground with a ‘fit and
forget’ approach,” said Tom Langton of Herpetofauna Consultants International,
Ltd., primary author on the guidance document. “This guide offers resource
managers in California opportunities and a clear plan to improve existing
crossings and build new ones to better standards where they are most needed. The guidance should be valued in
other states with similar wildlife-road issues and at the international level,
and amphibian species must cross roads to reach essential breeding and foraging
habitat, are slow moving or
are too small for drivers to see and avoid. Snakes and lizards may also be attracted to paved roads
that typically absorb and retain heat.
All these behaviors put them at high risk of vehicle collisions.
have a responsibility to maintain the highway system in a way that doesn’t
impede or disrupt wildlife, including the movement of California’s threatened
and endangered reptile and amphibian species,” said Caltrans Director Toks
Omishakin. “This study allows us to analyze feasible and
effective ways Caltrans can use ecologically-minded design to minimize
impacts on these wildlife populations.”
transportation agencies and wildlife managers have installed structures to
help amphibians, reptiles and other small animals cross highways safely, such
as tunnels under roads or barrier fencing.
agencies have made significant investments in these structures for many years,
there has been little research into how effective they are,” said Dr. Robert
Fisher, a U.S. Geological Survey (USGS) supervisory ecologist involved in the
study. “Management guidance informed by science is needed to help ensure this
critical infrastructure is safe for sensitive species.”
With these concerns in mind, the goals of the
collaborative project were to address this information gap using a logical
framework and to help transportation agencies like Caltrans plan barrier and
crossing structures more effectively.
To help Caltrans determine which reptile and amphibian
species to prioritize, USGS scientists created a ranking system for more than
160 species and sub-species, based on their vulnerability to road dangers.
Turtles, tortoises and snakes dominated the highest risk category. USGS also
developed a mapping system to allow Caltrans to easily find where the ranges of
high-risk species overlap with California highways and statewide conservation
efforts. Species ranked high and very-high risk of negative road-related
impacts include desert tortoise, California red-legged frog, sierra newt and
red diamond rattlesnake, among others.
Then, in a series of field experiments, the USGS
scientists investigated how reptiles and amphibians interact with different
types of fencing, how far high-risk migrating amphibians move along road
barrier fencing before “giving up” or finding a passage, and the effectiveness
of turnarounds at fence ends.
“We were happy to find that turnarounds at barrier fence ends were largely effective in changing the trajectory of many species to help lead them back toward a passage,” said Cheryl Brehme, the USGS project lead. A new video by USGS shows a California tiger salamander successfully make it to an underground crossing after being guided by one of these turnarounds.
“The elevated road-segment is really exciting,” said
Brehme, “because it can be made to any width and length enabling reptiles,
amphibians and other small wildlife species to freely move back and forth
across wide stretches of roadway.”
Caltrans used the results of these combined studies to produce the best management practices guide, which will inform the work of district biologists and engineers and will likely be useful to many other organizations involved in the planning and construction of transportation infrastructure. USGS has also released a comprehensive reportof its studies in conjunction with the new guidance document.
emphasizes that different landscapes – and different species – need a range of
solutions, and the needs of different species and their numbers will influence
positioning and sizes.
“Planning for smaller rare species calls for designs that take into account the sensitivities and needs of these understudied and often forgotten species” said Dr. Tony Clevenger of Western Transportation Institute, who led the development of the best management practices guide. The best practices guide was produced for Caltrans by the Western Transportation Institute of Montana State University with Herpetofauna Consultants International, Ltd and is based on existing knowledge and foundational studies by the U.S. Geological Survey Western Ecological Research Center.
California Department of Transportation (Caltrans)
Amy Bailey, Supervising Environmental Planner
MIT Press has released Cycling for Sustainable Cities, a new book focused on how to implement infrastructure, programs, and policies to make cycling safer, more practical, and convenient for urban residents. Of note, the chapter on “Social Justice and Cycling” was co-authored by WTI Research Associate Andrea Hamre, in collaboration with transport justice and equity scholars Karel Martens and Aaron Golub.
An NCHRP project led by WTI is the focus of a current feature article in Traffic and Transit, a national transportation publication. “Mapping the Future of Rural Transportation Research” highlights the development of the Research Roadmap for Rural Transportation Issues (NCHRP 20-122), which will provide a detailed, long-term agenda for research aimed at improving rural transportation throughout the U.S., including the creation of a series of research needs statements on specific topics. The project is led by Principal Investigator Jaime Sullivan, in collaboration with Iowa State University.
To date, the project team has produced 15 topical research portfolios; 26 research needs statements; and 13 research problem statements, which are more fully developed project proposals ready to submit for funding consideration. Sullivan provided an update on the project at the Transportation Research Board Annual Meeting, during the Rural Transportation Issues Coordination Council meeting, which she chairs. The new Council will serve as the home for ongoing activities related to the Research Roadmap project.
The U.S. Forest Service
has released a new report authored by wildlife crossing experts from WTI, ARC
Solutions, and other partner research organizations, which compiles key
guidance information that may lead to the installation of more wildlife
structures are one of the most effective means of reducing animal-vehicle
collisions on highways, while facilitating essential animal movement across the
landscape. Yet the widespread implementation of such structures, especially
wildlife overpasses, has been hindered by cost concerns. In 2014, WTI hosted a
workshop in partnership with ARC Solutions and prominent wildlife crossing
experts from Canada and the United States to determine whether there are design
parameters and construction techniques that could be added, changed, or
adjusted to reduce costs, while maintaining or improving the effectiveness of
during the workshop were developed into specific strategies. This document presents 32 potential cost
savings considerations, which were consolidated into three categories:
design and construction
procurement, delivery method, and cost accounting considerations
Citation: McGuire, Terry M.; Clevenger, Anthony P.; Ament, Robert; Callahan, Renee; Jacobson, Sandra, eds. 2020. Innovative strategies to reduce the costs of effective wildlife overpasses. Gen. Tech. Rep. PSW-GTR-267. Albany, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station.
The National Academy of
Sciences Transportation Research Board (TRB) is raising awareness of a new WTI
study on travel behavior, by highlighting it in its weekly newsletter.
Researchers Andrea Hamre and Jonathan Fisher recently completed “Travel Behavior and Transportation Planning Insights from the Small Urban Area of Chittenden County, Vermont: An Application of Traveler Segmentation,” sponsored by the Small Urban, Rural, and Tribal Center on Mobility (SURTCOM). The primary purpose of this project was to analyze transportation planning and travel behavior of County residents, using data from four travel surveys conducted over the last 20 years.
The survey series
collected information from respondents about travel preferences and priorities
for regional transportation investments. The research team applied traveler
segmentation to classify the survey sample into three modal orientations — Alternative [transportation] Oriented, Car
Tolerant, and Car Oriented.
According to the team’s analysis, nearly half (49%) of the respondents fell within the Car Tolerant segment. These respondents use their cars frequently, but also show a high willingness to change their travel behavior, as well as strong support for incentives to use alternative transportation. The team also found that Chittenden County adults would like fewer resources devoted to highways than are currently being allocated, and that support for gas tax increases is higher for non-highway purposes than for use exclusive to highways. These findings may help Chittenden County officials prioritize future transportation investments and develop multi-modal systems that meet a range of public needs.
WTI has completed a project to create a severe weather index for the Maryland Department of Transportation, and the final report was featured in a recent issue of the National Academy of Sciences Transportation Research Board’s newsletter.
A severe weather index
(SWI) is a management tool that can be
used to assess the performance and related costs associated with winter
maintenance operations – it considers the relative severity of each weather
event and the relative severity of weather for that season. On behalf of the Maryland DOT State Highway
Agency (MDOT SHA), WTI researchers Laura Fay, Natalie Villwock-Witte,
and Karalyn Clouser, in partnership with David Veneziano of Iowa State
University, developed and tested an SWI using Road Weather Information System (RWIS)
data and input from maintenance managers.
In addition to the development of the SWI itself, key outcomes of this effort include the identification of locations where blowing and drifting snow impacts the road network, the identification of future sites for RWIS stations, survey results describing RWIS use by MDOT SHA maintenance crews, and a detailed review of the RWIS network and data. The final report also provides recommendations to MDOT SHA for improving the SWI and overall winter maintenance operations. “We’re pleased that MDOT SHA is evaluating the tool and plans to implement it in the 2020-21 winter season,” said P.I. Laura Fay; “The sooner it’s used and assessed during actual storm events, the sooner it can be calibrated and refined, which will improve its usefulness.”
Bicyclist safety is a growing
concern as more adults use this form of transportation for recreation,
exercise, and mobility. Most bicyclist fatalities result from a crash with a
vehicle, and the behaviors of the driver are often responsible for the crash. The researchers conducted a survey study
of Montana and North Dakota residents and found that prosocial driver behavior
was most common and appeared to be intentional. They also found that this intention
was increased by positive attitudes, normative perceptions, and perceived
control. The findings can be used to develop strategies to increase prosocial intentions
and driver behavior, thereby increasing bicyclist safety.
CITATION: Ward, N. J., Finley, K., Otto, J., Kack, D., Gleason, R., & Lonsdale, T. (2020). Traffic safety culture and prosocial driver behavior for safer vehicle-bicyclist interactions. Journal of Safety Research. https://doi.org/10.1016/j.jsr.2020.07.003