Wildlife Crossings

Providing safe passage for urban wildlife

by Metro Regional Government

This guidebook, Achieving Landscape Permeability in an Urban Environment: Wildlife Crossings, providing safe passage for urban wildlife, provides recommendations to enhance the design and effectiveness of transportation planning processes within the context of evolving and complex scientific information and research. Implementing improved transportation planning processes will help to ensure Portland area roadways allow for the greatest possible movement of native fish and wildlife for the conservation of these species, while ensuring the safety of the motoring public. Both enhance the quality of life of Oregonians that value healthy fish and wildlife populations.

This guidebook complements the previous and ongoing work of Metro, including Metro’s Green Streets, Trees for Green Streets, Creating Livable Streets and Green Trails guidebooks as well as the work of others in the Portland

metropolitan area focused on inventorying, characterizing, and connecting important habitats for native fish and wildlife. The guidebook provides information on:

  • where to look for inventory information on wildlife populations in the Portland metropolitan area
  • the ecological effects of roads
  • the importance of identifying wildlife linkages
  • a decision guide to ensure wildlife mitigation
  • planning outcomes achieve goals
  • different types of wildlife crossing structures
  • potential sources of funding
  • the importance of monitoring wildlife populations and road crossing locations needed to assess landscape permeability
  • case studies and examples of wildlife crossings
  • supporting actions that can be taken to help achieve landscape permeability

Published August 2009

About the Author


Whether your roots in the region run generations deep or you moved to Oregon last week, you have your own reasons for loving this place – and Metro wants to keep it that way. Help shape the future of the greater Portland region and discover tools, services and places that make life better today.

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