Chinook Salmon Return to Olympic National Park

CC Image Courtesy of Dan Hershman

On August 20th, not even five months following the removal of the Elwha Dam, adult Chinook (king) salmon were seen in Olympic National Park for the first time since 1913, when the dam became operational and blocked over 70 miles of salmon habitat.

The salmon were spotted about two miles upstream of the park’s boundary by Phil Kennedy, the park’s Lead Fisheries Technician, who expressed his excitement at the sighting,

We knew this was going to happen and as I saw the fish roll, my heart jumped!”

Upstream Side of the Elwha Dam. Photo by Doug Zimmer (USFWS)

The removal of the 108 foot high Elwha Dam was the largest dam removal project in US history. Wrecking crews began demolition in September of 2011, predicting that it would take two to three years to bring the dam down. By March of this year, the dam was entirely gone, and the river began to flow in search of its old channels. Scientists were amazed at how quickly wild steelhead trout returned to habitat not visited by the species in almost 100 years.

Eight miles farther upriver is the Glines Canyon Dam, even larger than the Elwha Dam at 210 feet high. This 85 year old concrete dam is being demolished too, and has already been reduced to half its height. By early summer of 2013, it should be entirely gone as well, finally allowing fish to swim upriver in the waters that they swam in for millennia. Prior to the construction of the two concrete dams, the Elwha River was packed with hundreds of thousands of fish, including all five native Pacific salmon species.

Olympic National Park’s Fisheries Crew has been conducting weekly surveys along the Elwha River since the beginning of August, hoping to sight Chinook salmon returning to the park.

The Chinook salmon, Oncorhynchus tshawytscha, is the largest species of salmon in the Pacific salmon family. Weighing an average 10-50 pounds, Chinook salmon spend an average of three to four years living in the ocean before returning to their home rivers to spawn. After laying their eggs, the female Chinook salmon guard the redds as the nests are known for 4-25 days before dying, while the males continue to look for additional mates. The eggs hatch from 90-150 days after being deposited, after which the young fish, known as fry and parr generally remain in the fresh water of the river for twelve to eighteen months before heading downstream to the shallow estuaries where they remain as smolts for several months.

“Observation of these Chinook in Olympic National Park is a wonderful addition to the naturally returning steelhead recently observed by NOAA Fisheries and Lower Elwha Klallam Tribe downstream of the park boundary,” said Olympic National Park Fisheries Biologist, Sam Brenkman.