Summary
The Yamhill river is a Willamette river tributary that drains 529,510 acres and runs from the east side of Oregon’s coast range mountains to the Willamette river. Native Americans inhabited the watershed and maintained the native oak savannah habitat through prairie burning. Upon European settlement, the burning ceased, and the land was converted to agricultural and timber harvest uses. Extensive splash damming on the river and major tributaries led to a loss of channel complexity, erosion, lack of large wood habitat, and lack of spawning gravel for native fish. A lock and dam operated for barge traffic on the Yamhill river from the early 1900’s until it’s removal in the 1960’s. The dam was an impediment to fish passage. Hatchery introductions for Coho salmon and winter steelhead occurred through the 1960-1980’s but were discontinued due to low returns and concerns about impacts to native fish species. Today, the river supports populations of native coastal cutthroat trout, Willamette winter steelhead, and naturalized Coho salmon.
Native Species
- Coastal Cutthroat Trout
- Winter Steelhead [esa-listed]
- Pacific-lamprey
- Western Brook Lamprey
Wild Fish Species:
- Coastal Cutthroat Trout (Federal Listing: Species of Concern, State Listing: Sensitive)
This are the most abundant cold-water fish species in the watershed. They are used as an indicator of water and habitat quality. There are 2 known life histories present, resident and fluvial.
- Willamette Winter Steelhead (Federal Listing: Threatened, State Listing: Sensitive)
Winter steelhead occurred historically in the South Yamhill watershed, although there is little information about whether a self-sustaining population existed or not. Steelhead from the Big Creek hatchery were stocked heavily in the watershed from the 1960-1980’s by ODFW. Willamette winter steelhead were federally listed as threatened in 1999. NOAA reports that the Upper South Yamhill has the highest conservation potential in the watershed due to the high quality of available habitat (2005). In 2017, Only 822 native steelhead returned to Willamette falls and the future of returning steelhead in the Yamhill is uncertain.
- Coho Salmon (naturalized)
Coho salmon were stocked in the Yamhill by ODFW through the 1960-1980’s. Descendants of these stocked fish still return and spawn in the watershed.
- Pacific Lamprey (Federal Listing: Species of Concern)
These primitive jawless fish return from the ocean every year to spawn in the tributaries of the Yamhill river. Little is known about their abundance and distribution in the Yamhill, however, an overall decline in abundance in the region is concerning. Pacific lamprey are culturally important to the Confederated Tribes of Grande Ronde.
- Western Brook Lamprey (Federal Listing: Species of Concern, State Listing: Sensitive)
Unlike Pacific lamprey, Western brook lamprey remain in freshwater throughout their life. They are sensitive to poor water quality and migration barriers such as culverts.
Major Tributaries:
- North Yamhill River
- South Yamhill River
- Willamina Creek
- Agency Creek
- Mill Creek
- Deer Creek
- Salt Creek
Threats:
- Hatchery rainbow trout
Fish are stocked annually in the South Yamhill River with little bank access, low angler turnout, and an already present population of native coastal cutthroat trout.
- Water Quality
Pollution from Urban, Agricultural, and Forest Management Runoff affect water quality.
- Sedimentation
High water temperatures, low water levels, and sedimentation occur from land use activities
- Loss of Wetland Habitat
Much of the wetland habitat in the Yamhill watershed has been drained for agricultural use.
- Historic splash damming
Splash damming on the river and major tributaries has resulted in a loss of spawning gravel, large wood, and channel complexity.
- Invasive Fish Species
Non-native fish species, such as smallmouth bass and channel catfish, have been introduced to the watershed.
News and media within the basin:
- Hatchery Trout Stocking http://www.statesmanjournal.com/story/travel/outdoors/2014/04/12/trout-hand-dropped-into-stretch-of-yamhill-creates-hot-spot-in-uncrowded-area/7652701/
Conservation Partners within the Basin:
- Greater Yamhill Watershed Council has accomplished much involving habitat restoration, culvert replacement, water quality monitoring, chemical recycling, watershed education, fish monitoring, and invasive plant removal.
- The Confederated Tribes of Grande Ronde monitors steelhead, Coho salmon, and Pacific lamprey on Agency Creek.
For more information regarding the Yamhill Watershed visit these links:
- National Marine Fisheries Service CHART Assessment for the Upper Willamette River Steelhead ESU
- Willamette Winter Steelhead (ODFW)
- Genetic characterization of coho salmon (Oncorhynchus kisutch) in Agency Creek, a tributary to the South Yamhill RiverAgency Creek, a tributary to the South Yamhill River
- Upper South Yamhill River Watershed Assessment
- Lower South Yamhill-Deer Creek Watershed Assessment
- Willamina Creek Watershed Assessment
- Lower Yamhill Watershed Assessment
- Mill Creek Watershed Assessment
- Oregon Explorer: Yamhill watershed
