Willapa National Wildlife Refuge: Vegetation Mapping and Ecological Integrity Assessment

Willapa National Wildlife Refuge in southwestern Washington

About This Project

We conducted field surveys of sample locations to help mappers interpret aerial photography (taken from airplanes) and remote imagery (taken from satellites) that covered the entire refuge, and used standard U.S. National Vegetation Classification to determine the vegetation types.

We also conducted an assessment of the condition or health status of wetland and upland habitats. This type of ecological integrity assessment helps determine if a habitat is functioning fully, or is in some way in need of management attention. We looked for answers to a variety of questions. Example questions included: Is a patch of habitat large enough to support all expected species? Are there any noxious weeds present or super abundant? Is the soil in good shape or is there too much erosion or compaction? Is the amount and timing of water in wetlands supportive or lacking? Are management activities such as grazing or mowing conducive to conservation of the habitat’s full suite of species it supports? Does the surrounding landscape provide buffers and corridors for wildlife movement?

Based on the findings we gave each habitat a grade of A for excellent health, B for good health, C for fair and D for poor condition.

Upland Ecological Integrity Assessments are also being developed. See examples here.


This project was designed to create an up-to-date and accurate map of the Willapa National Wildlife Refuge vegetation and to determine the health or status of that resource.

Goals for this project were to:

  • Determine the status or health (known as ecological condition) of wetland and upland habitats.
  • Determine if there are excellent examples of intact native habitats within refuge boundaries that can be used as reference sites for restoration of damaged areas.
  • Articulate the relationship between USFWS wildlife habitat types and the U.S. National Vegetation Classification units.
  • Use standard U.S. National Vegetation Classification units for the vegetation map and avoid ad hoc map units.


An up-to-date, accurate and standardized vegetation map is a useful tool for land management. This map will be used not only to understand current amount and locations of various habitats, but also to target and prioritize research projects and management activities.

Using U.S. National Vegetation Classification standard units shows how important this refuge is in protecting specific western habitats and allows managers to “roll up” the same habitats across refuges throughout the region and nationwide, so individual refuge assessments can lead to regional and national assessments. An important part of this project is the crosswalk of the many wildlife habitat names USFWS uses to standard National Vegetation Classification units. Using standard classification units allows for comparisons with other mapped areas across the region and the nation, which tells us how well we are protecting and conserving the biodiversity at local, regional and national scales.