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The Corridor

The WWRP project area encompasses an essential linkage of the Westside Wildlife Corridor in SW Portland, a section of the west hills that includes undeveloped natural habitats and streams. We are working to enhance the functionality of this wildlife migration corridor, forming a connection between Tryon Creek State Natural Area in the South and Forest Park in the North. Ultimately, we hope to help maintain a healthy wildlife corridor connecting SW Portland's natural areas all the way to Oregon's Coast Range.

Image from an ArcGIS Story Map by Andrew Addessi, Portland State University: 

The Corridor & People

The Westside Wildlife Corridor that connects Forest Park to Tryon Creek State Natural Area is enjoyed by nearby residents, students, and other users of Terwilliger Parkway and Marquam Nature Park. Access to this corridor and other urban green spaces is important for many reasons, including human health & well-being, safety, and educational and economic benefits. 

Human Health & Well-Being

Nearly 40 years of research shows that the experience of nature is important to human functioning, health, and well-being. Access to urban green spaces has the potential to: 

  • Increase physical activity

  • Lower stress levels

  • Create positive social interactions

  • Improve mental health and wellness

  • Foster a sense of unity among residents

Human Safety

 The presence of weedy plants:

  • Can take down trees & power lines

  • Provide little protection against erosion on slopes.

Educational Benefits
  • Opportunities for research

  • Access to outdoor hands-on learning

  • Improved academic performance

Economic Benefits
  • Increase property value

  • Reduce energy costs

To learn more about the benefits of urban green spaces and the research that ​is being conducted, please visit Green Cities: Good Health 

The Corridor & The Environment

Wildlife corridors are linked areas of land or habitat that connect larger green spaces together, creating passageways for wildlife to travel from one location to another. The ability for native wildlife to freely move through these corridors is an essential part of finding food, shelter, and a mate. 

As urbanization continues to encroach on our natural areas, corridors are becoming increasingly important to local wildlife. The Westside Wildlife Corridor connects wildlife habitat and clean water resources between Forest Park and Tryon Creek State Natural Area and is an important area for many native species and special status habitats. 

The West Willamette Restoration Partnership (WWRP) supports habitat enhancement and stewardship efforts in southwest Portland’s Willamette River subwatersheds. This includes, but is not limited to, Marquam Nature Park, Terwilliger Parkway, Keller Woods, George Himes City Park, Riverview Natural Area, and other green spaces in between. The ecological health of these areas has been degraded by the spread of non-native plant species like Irish and English ivy, English holly, and Himalayan blackberry. We aim to improve conditions supportive of native flora and fauna through good land stewardship, volunteerism, and education.

OHSU, Marquam, Terwilliger

This map depicts OHSU and the surrounding parks and natural areas, including Marquam Nature Park and Terwilliger Parkway. Trails can be seen in red. 

Special Status Habitats
  • The corridor includes a 25 acre area of oak habitat – a rare remaining grove of the native Oregon white oak trees that used to dominate the Willamette Valley.

  • Upland mixed conifer forests, another special status habitat found within the corridor, provides a multi-layered tree canopy and a high volume of dead wood.

Conservation Strategy Species

Strategy Species are those that have small or declining populations, are at-risk, and/or are of management concern. Some of the Conservation Strategy Species that use the Southwest Wildlife Corridor include:

  • White-breasted Nuthatch

  • Pileated woodpecker

  • Douglas's squirrel

  • Northern flying squirrel

Healthy wildlife corridors promote local biodiversity, which

  • Supports native pollinators

  • Supports nutrient cycling and soil fertility

  • Increases ecological stability and resilience following a disturbance

Additional Benefits

Paved surfaces and rooftops found in urban areas create a wide range of environmental issues. Urban green spaces provide shaded, moist areas and permeable surfaces and can protect cities from the following negative environmental impacts:

  • Urban Heat Island Effect 

  • Air pollution & greenhouse gases

  • Impaired water quality

To learn more about the projects that WWRP and the partners ​are working on to conserve and restore the Westside Wildlife Corridor, check out our projects page:

For People
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