15 million salmon go under the knife

UNDERWOOD, Skamania County — The task is to make hatchery-bred salmon distinguishable from wild salmon so that commercial fishermen and sport anglers can tell them apart.

Here's how it's done at the Spring Creek hatchery here:

Suck one roughly 3-inch fingerling through a series of plastic tubes into a 44-foot trailer. Take video to determine its size within one-tenth of a millimeter.

Sort it using computers, water jets and flapping plastic ports into one of six tubes. Guide the tiny fish into an "AutoFish" machine that holds the fish still and quickly slices off its adipose fin.

Take another video to make sure the fin came off right. Send it back through another tube into the hatchery pool.

Repeat 15 million times.

That's the drill right now for operators of Spring Creek National Fish Hatchery, near the White Salmon River. They're working double shifts and marking an average of 264,000 Columbia River tule fall chinook a day in AutoFish and manual-marking trailers that move to hatcheries up and down the river.

The four-year-old mass-marking program isn't cheap: The automated trailers cost $1 million apiece; operating costs of fish marking in federal hatcheries alone run $1.5 million a year.

And the program has its critics, most significantly Native American tribes. They question the benefit to wild fish of marking nearly every hatchery salmon and steelhead in dozens of Washington and Oregon hatch.

Fishery managers say the congressionally mandated program helps fishermen distinguish hatchery fish from wild fish, expanding the potential take of hatchery fish.

Fishermen aren't required to release wild tule fall chinook but probably soon will be, fishery managers say.

Tule fall chinook raised in the hatchery are released into the Columbia in the spring, about six months after hatching.

They migrate 167 miles to the river mouth, then turn north, heading into open ocean off the coasts of Washington and British Columbia to feed for one to four years before returning upriver to spawn.

When the fish reach the hatchery in late August, workers take nearly 5,000 eggs from each female, moving them to an incubation building and starting the process over.

Northwest Marine Technology of Shaw Island, in San Juan County, worked with the Fish and Wildlife Service, Washington state and the Bonneville Power Administration to develop the AutoFish system.