U.S. Fish and Wildlife Service hatcheries release Chinook salmon

On April 11, Spring Creek NFH released 6.7 million tule fall Chinook salmon directly into the Columbia River. On April 20, they released their remaining 3.8 million tule fall Chinook salmon. This important stock of fish supports river and coastal fisheries off Washington and British Columbia.

Little White Salmon NFH released 1.5 million spring Chinook salmon directly into the Little White Salmon River, Carson NFH released 1.5 million spring Chinook into the Wind River, and Warm Springs NFH released 186,736 spring Chinook salmon into the Warm Springs River, a tributary of the Deschutes River.

The salmon releases are timed to benefit from the Bonneville Dam spill that started on April 10. The spill decreases the time it takes juvenile salmon and steelhead to move through the system of dams to the Pacific Ocean.

Returning adult Chinook from the Columbia River hatcheries support Columbia River sport, commercial and Tribal fisheries in the river and a highly successful Tribal fishery in Drano Lake.

Chinook production at Columbia River Gorge NFHs is operated to avoid ecological risks with the federally listed salmon and steelhead (rainbow trout that migrate to the ocean). The hatchery releases fulfill important legal responsibilities the U.S. government has to Native American Tribes under the U.S. v. Oregon Management Agreement, as well as federal government responsibilities to mitigate for lost salmon production and spawning grounds due to the construction of hydropower projects that are part of the Federal Columbia River Power System.

Hatchery releases are timed to coincide with the annual outmigration of young salmon to the ocean, a cycle that begins with the young fish making a downstream journey — swimming backwards — to the Pacific Ocean, where they will live for one to five years or more, then return as adults to their natal (home) streams, where they spawn and die.

In addition to its on-station release, Carson NFH transferred nearly 370,000 spring Chinook eggs to the Confederated Tribes of the Umatilla Indian Reservation last August. The egg transfer jump starts the Tribe’s propagation program to re-establish a salmon run in the Walla Walla River that was extirpated for 80 years until 2005, when the Umatilla Tribe’s reintroduction program began. Carson NFH also transferred 250,000 eyed eggs to Washington Department of Fish and Wildlife for restoration in the Touchet River in eastern Washington last October.

Willard NFH in Cook, Wash., has already transferred 755,000 coho salmon in pre-smolt stages to various Yakama Indian Nation acclimation sites, including the Leavenworth NFH Complex in the Wenatchee and Methow River basins. These rivers are tributaries of the Columbia River and the work undertaken by the Service and the Yakama Nation are part of a larger Mid-Columbia River Coho Reintroduction Program.

A smolt is a juvenile salmon whose physiology is adapting from living in freshwater to saltwater ecosystems. Smoltification occurs as young salmon migrate towards the ocean and is a complex series of physiological changes that allow fish to adapt from living in fresh water to salt water.

Adult salmon’s migration and ability to locate and return to the stream where it was born is considered one of nature’s most remarkable phenomena. Salmon and steelhead have acute senses of smell; they are believed to be able to detect chemical signature concentrations in water as small as one or two parts per million, equivalent to being able to sniff out a single drop of water in 250 gallons. Members of the salmon family, Salmonidae, have existed on Earth for at least 50 million years.

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Cheri Anderson is an information and education specialist with the Columbia River Gorge National Fish Hatchery Complex.