Environmental Management

, 42:480 | Cite as

An Assessment of Road Impacts on Wildlife Populations in U.S. National Parks

  • Rob Ament
  • Anthony P. ClevengerEmail author
  • Olivia Yu
  • Amanda Hardy


Current United States National Park Service (NPS) management is challenged to balance visitor use with the environmental and social consequences of automobile use. Wildlife populations in national parks are increasingly vulnerable to road impacts. Other than isolated reports on the incidence of road-related mortality, there is little knowledge of how roads might affect wildlife populations throughout the national park system. Researchers at the Western Transportation Institute synthesized information obtained from a system-wide survey of resource managers to assess the magnitude of their concerns on the impacts of roads on park wildlife. The results characterize current conditions and help identify wildlife-transportation conflicts. A total of 196 national park management units (NPS units) were contacted and 106 responded to our questionnaire. Park resource managers responded that over half of the NPS units’ existing transportation systems were at or above capacity, with traffic volumes currently high or very high in one quarter of them and traffic expected to increase in the majority of units. Data is not generally collected systematically on road-related mortality to wildlife, yet nearly half of the respondents believed road-caused mortality significantly affected wildlife populations. Over one-half believed habitat fragmentation was affecting wildlife populations. Despite these expressed concerns, only 36% of the NPS units used some form of mitigation method to reduce road impacts on wildlife. Nearly half of the respondents expect that these impacts would only worsen in the next five years. Our results underscore the importance for a more systematic approach to address wildlife-roadway conflicts for a situation that is expected to increase in the next five to ten years.


Data collection Habitat fragmentation Mitigation Mortality National park Survey Road ecology Road network Transportation Questionnaire Wildlife management 



This work was conducted as part of the 2004 WTI Research for Undergraduates (REU) Program at Montana State University. The Western Transportation Institute’s Summer Research Experience for Undergraduates (REU) Program in Rural Transportation provided support each summer to eight undergraduate students from colleges and universities nationwide to pursue a ten-week research program at Montana State University in Bozeman. The program was funded by the National Science Foundation/Department of Defense and the U.S. Department of Transportation’s Research and Special Programs Administration. Olivia Yu was the REU student who helped conduct the survey. We would like to thank the many employees of the National Park Service who took the time to assist us in our survey as well as Jim Evans and Susan Grosser who checked our facts and reviewed a draft of the manuscript. We are particularly grateful to Natasha Kline and Ray Sauvajot for their review and constructive input, which greatly improved the final draft. The following people provided support and assistance on the project: Meredith Evans Wagner helped fill in gaps from the original article. Angela Kociolek reviewed and commented on a draft of the manuscript. Kate Heidkamp provided generous support to complete the manuscript. We thank Susan Gallagher for her help in planning and coordinating the Research Experience for Undergraduates program at Montana State University-Bozeman.


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Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • Rob Ament
    • 1
  • Anthony P. Clevenger
    • 1
    Email author
  • Olivia Yu
    • 1
    • 2
  • Amanda Hardy
    • 1
  1. 1.Western Transportation InstituteMontana State UniversityBozemanUSA
  2. 2.USDA Environmental Microbial Safety LaboratoryMarylandUSA

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