The Sol Duc River on the northwestern Olympic Peninsula runs at its lowest and warmest when summer chinook return to its waters every year. Despite being in one of the world’s greatest temperate rain forests, near-drought conditions often occur in late summer before the fall rains begin in earnest.
“These fish are survivors,” said Roger Lien, fish biologist for the Quileute Tribe. After four to five years at sea, the fish return to their river of birth at a difficult time. Low flows go hand in hand with higher water temperatures, placing enormous stress on the fish and making them susceptible to disease. Water temperatures near 70 degrees can be lethal to salmon.
“The run has never been real robust and it’s highly variable, but it’s an important one,” Lien said. “That’s why the Quileute Tribe saw it as a good candidate for supplementation.”
Each year, the tribe captures wild male and female chinook from mid-July to September to spawn and rear about 200,000 of their offspring cooperatively with the Washington Department of Fish and Wildlife at the agency’s Sol Duc Hatchery. The fish are later transferred to the tribe’s Lonesome Creek Hatchery before being released in the Sol Duc River.
The supplementation effort aims to support, not replace, natural salmon production in the system. Adequate numbers of returning adults are allowed to pass upstream to maintain natural escapement – the number of fish needed to spawn and perpetuate the run. Summer chinook provide important fishing opportunity for tribal and non-tribal fishermen.
“There isn’t much in-river fishing opportunity in the summer, so these fish can help put food on the table and provide for cultural ceremonies,” Lien said.