Klamath Marsh-Williamson River – State Wildlife Action Plan

Forest and wetland habitats in the Klamath Marsh/Williamson River Conservation Opportunity Area, State Wildlife Action Plan — Photo Credit: William Tinniswood, COA

Geographic boundaries of the COAs were updated for the 2026 State Wildlife Action Plan and the associated COA profiles are intended to provide additional information. Content of each COA profile is being refined and will be updated to reflect current conditions when feasible. Please help us by submitting information on Local Conservation Actions, Plans, or Potential Partners to: OCS.revision@odfw.oregon.gov.

Large natural marsh with adjacent Ponderosa Pine forest habitat. Williamson River area spans Klamath Marsh National Wildlife Refuge and Sycan Marsh.

Recommended Conservation Actions

Maintain corridors for wildlife movements and habitat connectivity
Maintain or enhance in-channel watershed function, flow and hydrology
Maintain or enhance Ponderosa Pine and Forest habitat
Maintain or restore riparian habitat; provide complex habitat for wildlife
Maintain, enhance and restore Wetland habitat

Local Conservation Actions and Plans

Potential Partners

Natural Resources Conservation Service
US Fish and Wildlife Service
US Forest Service

Special Features

General

Ajacent to Klamath Marsh National Wildlife Refuge
Heavy use by migrating waterfowl
Important habitat for sandhill cranes and trumpeter swans

Previously Associated With

2006 COA ID EC-10 (Klamath Marsh)
2006 COA ID EC-11 (Williamson River area)

Ecoregions

East Cascades

The East Cascade ecoregion extends from the Cascade Mountains' summit east to the warmer, drier high desert and down the length of the state. This ecoregion varies dramatically from its cool, moist border with the West Cascades ecoregion to its dry eastern border, where it meets sagebrush desert landscapes.

Key Habitats

Aspen Woodlands

Aspen (Populus tremuloides) woodlands are woodland and/or forest communities dominated by aspen trees with a forb, grass, and/or shrub understory. Aspen woodlands also occur within conifer forests.

Late Successional Mixed Conifer Forests

Late successional mixed conifer forests provide a multi-layered tree canopy, including large-diameter trees, shade-tolerant tree species in the understory, and a high volume of dead wood, such as snags and logs.

Natural Lakes

Natural lakes are relatively large bodies of freshwater surrounded by land that were formed through geological processes, such as glacial scouring, tectonic movements, volcanic activity and river meander cutoffs. In Oregon, natural lakes are defined as standing water bodies larger than 20 acres, including some seasonal lakes. Depth is not a reference for characterization of …

Ponderosa Pine Woodlands

Ponderosa pine woodlands are common in Oregon’s eastside ecoregions. While dominated by ponderosa pine, these woodlands may also have lodgepole pine, western juniper, aspen, western larch, grand fir, Douglas-fir, mountain mahogany, incense cedar, sugar pine, or white fir, depending on ecoregion and site conditions. Known for their open forest structure, these woodlands generally have fewer …

Flowing Water and Riparian Habitats

Flowing Water and Riparian Habitats include all naturally occurring flowing freshwater streams and rivers throughout Oregon as well as the adjacent riparian habitat.