Survey reveals Elwha River Chinook are colonizing new habitats below Glines Canyon Dam

Two years after dam removal began, thousands of Chinook salmon have returned to the Elwha River and found their way into newly accessible stretches of the river and its tributaries to spawn.

On Sept. 17, a team of biologists representing Olympic National Park, Lower Elwha Klallam Tribe, U.S. Geological Survey, Washington Department of Fish and Wildlife (WDFW) and NOAA Fisheries navigated over 13 miles of the Elwha River and tributaries with the goal of counting all the living and dead adult Chinook and map the spawning salmon’s redds. Biologists walked and snorkeled the river from just below what remains of Glines Canyon Dam to the Strait of Juan de Fuca, as well as the lower portions of three of the river’s tributaries – Indian Creek, Hughes Creek, and Little River.

Results from the survey indicate this year’s Chinook return is one of the strongest since 1992 and reveal that the salmon are readily moving into stretches of the river formerly blocked by the Elwha Dam.

During the one-day survey, the biologists counted 1,741 adult Chinook and mapped 763 redds between the remnant of Glines Canyon Dam and the river mouth. Out of the total number counted, approximately seventy-five percent, (1,287 of the adult Chinook and 592 of the redds,) were observed upstream of the former Elwha Dam site. The total count included adult Chinook and redds observed in Indian Creek, Little River, and Hughes Creek, a tributary that remained unoccupied last year.  

“It is truly exciting to see the Chinook finding their way into clear water tributaries and reaching the base of Glines Canyon Dam,” Olympic National Park Superintendent Sarah Creachbaum said.

"This is what we have always known was coming. However, we also know that high sediment flows will again fill the river when dam removal resumes this fall. We are grateful for our partnerships with the Lower Elwha Klallam Tribe and the Washington Department of Fish and Wildlife that are providing human created refuges in their hatchery facilities. With hatcheries providing a refuge during peak sediment flows, we can preserve native fish populations during this critical phase of the restoration process.”

Protecting the genetic diversity of salmon populations during dam removal is a critical goal of the Elwha River Restoration Plan.

The Elwha River was once one of the most productive salmon streams in the Pacific Northwest, home to all five species of Pacific salmon. Since 1986, the average annual run size for Elwha Chinook has been 2,777 adults. Visual counts from last week’s survey, coupled with 1,797 adult Chinook collected by WDFW to meet stock preservation goals, bring this year’s total number of observed adult Chinook in the Elwha River to 3,528.

When dam removal is completed next fall, Elwha River salmon and steelhead will once again have access to over 70 miles of unaltered river and pristine spawning habitat. Their populations are expected to grow to nearly 400,000.

Removal of the two Elwha River dams is the largest project of its kind in U.S. history and is part of the landmark Elwha River Restoration project. For more information, including links to project webcams and the Dam Removal Blog, visit the Olympic National Park website at http://www.nps.gov/olym/naturescience/elwha-ecosystem-restoration.htm.