Researchers to study newly discovered sturgeon spawning area in Willamette River
By Oregon Dept. of Fish and Wildlife,
CLACKAMAS, Ore. — Researchers from the Oregon Department of Fish and Wildlife recently began surveying the Willamette River downstream of Willamette Falls to learn more about a previously unknown white sturgeon spawning area. According to Tucker Jones, ODFW white sturgeon project leader, researchers were surprised to discover white sturgeon spawning in the Willamette River last spring. Until then, the only known spawning grounds for the lower Columbia River white sturgeon population, which includes sturgeon in the lower Willamette River, was immediately downstream of Bonneville Dam on the Columbia River.
“White sturgeon are important recreationally, commercially, culturally and ecologically,” said Jones. “Identifying another sturgeon spawning area is a big deal.”
Researchers have received a $44,187 grant from the ODFW Fish Restoration and Enhancement Program to help get a clearer picture of the extent and timing of sturgeon spawning in the Willamette.
To determine the level of white sturgeon spawning activity downstream of Willamette Falls, researchers will try to collect eggs using substrate mats that will catch the eggs as they settle on the river bottom. Sturgeon are broadcast spawners, laying their eggs throughout the water column. The eggs then sink and adhere to the river bottom to incubate.
Tucker planned to conduct the survey from April to the end of June, when seasonal water temperatures are usually optimal for sturgeon spawning. However, unseasonably warm weather this spring has prompted an earlier start to the research.
In time, researchers hope to map the exact size and location the spawning area in the Willamette River, and document when spawning takes place and what environmental conditions, such as water temperature, influence spawning activity.
The white sturgeon is an ancient species of fish native to the Pacific Coast of North America from Alaska south to Baja California. They can live in the ocean, estuaries or freshwater rivers, but only spawn in the Columbia, Sacramento, and Fraser river systems. Growing up to 20 feet long, they are the largest freshwater fish in North America.
The lower Columbia River sturgeon population provides an important and popular recreation fishery and almost 180,000 lower Columbia River white sturgeon were harvested by anglers between 2003 and 2008.
The discovery of a sturgeon spawning ground in the Willamette River recently prompted the Oregon Fish and Wildlife Commission to adopt new sport fishing regulations to help protect spawning fish. These include: a) establishing a seasonal sturgeon spawning sanctuary on the Willamette River between Willamette Falls and the I-205 bridge from May through July, and b) closing the bank fishing area in Oregon City known colloquially as “The Wall.”
The ODFW Fish Restoration and Enhancement Program, which provided funding for the research, was created by the Oregon Legislature in 1989 and is funded by a surcharge on sport and commercial fishing licenses and commercial poundage fees. The program’s seven-member citizen board reviews fish restoration and enhancement project proposals and makes funding recommendations to the Oregon Fish and Wildlife Commission.
For more information on the Fish Restoration and Enhancement Program, or to view information regarding current R&E Program applications, visit www.dfw.state.or.us/fish/RE or contact program coordinator Laura Tesler at (503) 947-6259.