Photos: What a fish hatchery does

The damming of Washington’s Elwha River in the early 1900s destroyed an age-old ecosystem of salmon and steelhead trout. It also set a precedent across the West for letting hatcheries do the job of reproduction. The Elwha was recently undammed, part of the largest river-restoration project in U.S. history — but it still hosts controversial hatcheries. In this photo from August 2012, workers from the state wildlife department prepare to net adult Elwha salmon in order to collect their eggs. John Gussman

Studies show that hatchery salmon are less adept at mating and avoiding predators than those in the wild. Nevertheless, due to overfishing and destroyed habitat, some rivers owe their entire salmon populations to hatchery production. John Gussman

This pink salmon is examined for hatchery markings then released to spawn in the Elwha by state fish and wildlife staff. Washington has 83 hatchery facilities run by the state, 51 by tribes and 12 by the federal government. John Gussman

The state maintains several hatchery facilities on the Elwha and its tributaries. Juvenile salmon are reared in holding pens and raceways before swimming out to the river, then the Strait of Juan de Fuca and eventually the Pacific Ocean. John Gussman

Some three million young salmon are released into the Elwha and its tributaries every year by the state hatchery. They travel to the sea, where they spend most of their lives, before returning upstream to their natal rivers to mate and die. Last year, the river saw its best returns of chinook in three decades: 4,500 adults. John Gussman

A sign in English and the Klallam language hangs outside the hatchery on the Lower Elwha Klallam reservation, circa November 2011. The facility is a point of pride for the Elwha people, whose four full-time hatchery workers trap, gaff, fertilize, feed, move and tag millions of fish every year. But the $20 million hatchery is also the subject of a federal lawsuit alleging that its production and release of young salmon harms threatened, wild species under the Endangered Species Act. John Gussman

In the Elwha River, hatchery fish are marked — usually with a fin tag or microchip — to distinguish them from wild fish. In a photograph from November 2011, tribal hatchery manager Larry Ward (wearing a black hat) oversees this process. This year, the Lower Elwha tribe plans to release 175,000 native steelhead trout, 425,000 coho salmon, more than 1 million chum salmon and 3 million pink salmon. John Gussman

Biologist John McMillan, formerly employed with the Lower Elwha tribe and now with the nonprofit Trout Unlimited, carries coho salmon into the Elwha River in November 2011. He and his colleagues hoped to aid the fish in reaching their upstream spawning grounds. John Gussman

McMillan releases an adult coho into the river in November 2011, hoping it will mate and help heal the decimated population of these fish in the Elwha. Billions of dollars have been spent to manage and multiply fish in the U.S., but salmon populations continue to shrink year after year. The Elwha restoration is a grand experiment in reversing this trend. John Gussman