Use of hatchery salmon to boost wild runs raises thorny questions
Seattle Times staff reporter
In the heat of the midday sun, a female chinook thrashes her tail to dig out a gravel egg nest. Clumps of fungus mottle her skin, and her inner flesh has turned mushy white. Still, she stays on task, shooing away several hook-nosed males eager to shed their sperm.
But here on the Kalama in Southwest Washington and numerous other Washington rivers, things are not always as they seem.
Many of the spawning salmon were born in the stainless-steel trays of hatcheries and are now being encouraged to mate in the rivers to try to boost the population of wild runs listed under federal Endangered Species Act.
This practice raises a complicated and fundamental question in the multibillion-dollar regional effort to save wild Northwest salmon runs: When is a wild fish really wild, with the genetic smarts to help sustain healthy runs for generations to come?
Studies have shown that domesticated hatchery fish often display traits different from those of their wild counterparts. So turning hatchery salmon loose to breed stokes intense debate, with some scientists saying the practice will harm, rather than help, many wild runs.
They also are concerned that the tactic could be a diversion from the most important and difficult task: improving and expanding the fresh water spawning and rearing areas needed by wild fish.
"The jury is still out on whether this can work — or cause long-term problems," said Jim Lichatowich, a biologist and author of one of the classic books on the fate of wild runs, "Salmon Without Rivers."
But federal National Marine Fisheries Service officials have made an important determination that is bolstering the hatchery efforts. They have determined that hatchery salmon that mate in streams can produce "wild offspring," which then qualify for protection under the federal Endangered Species Act.
And the movement to spawn more hatchery fish in the streams is gaining strength.
Here in Washington state, most hatchery fish that make it back to fresh water are either caught or return to the hatcheries.
But roughly a third of the 69 state-operated salmon and steelhead hatcheries, including some in the Puget Sound area, allow a portion of their fish to spawn in the rivers.
State officials say they've learned from the mistakes of years past, and can now use hatcheries to help revive wild runs.
"This is definitely growing every year," said Chuck Johnson, a state Department of Fish and Wildlife biologist who manages Southwest Washington salmon runs. "There are a lot of places where we think this can help."
This year, big numbers of hatchery spawners also are showing up in many Northwest rivers as some of the strongest salmon runs of the past quarter-century return from ocean feeding grounds.
At Bonneville Dam on the Columbia River, fish counters reported a record passage of more than a half-million fall chinook, with roughly 80 percent born in hatcheries.
The big return appears to be due to several years of dramatically improved ocean conditions, with salmon gorging on huge schools of bait fish massed along the coast.
And the Kalama, which empties into the Lower Columbia, below the dam, is sharing in the salmon bounty. This is a well-worn drainage, with upper reaches that have been heavily logged and lower floodplains full of farm fields, dikes and riverside homes.
Three years ago, only about 1,500 fish straggled back to spawn along an eight-mile stretch of the lower Kalama.
This fall, biologists expect 10,000 to 15,000 fall chinook — most of them born in hatcheries — to spawn in the same stretch.
Most are already in the river, big fish that easily top 30 and 40 pounds, some making pogo-sticklike leaps 12 feet in the air as they try to vault a waterfall.
But producing hatchery fish is not cheap, with some facilities' costs running from dozens to hundreds of dollars for each adult fish reared.
Beyond the public cost, scientific reviews of the past decade have documented important differences between the artificially propagated fish and their wild counterparts. And they cite instances when the release of hatchery fish has harmed wild stocks.
Wild stocks evolved over centuries with distinctive genetic codes that fit the watersheds of their birth. These genetics may dictate the timing of migration, the amount of body fat needed to sustain them on their journey to fresh water spawning grounds and other key traits.
In the 1890s, hatchery managers had little understanding of the complex genetics of salmon and paid little attention to maintaining the genetic integrity of wild fish. They drew a small selection of salmon from a variety or watersheds, and then often released these fish into other creeks and rivers.
The smolts — at the time of release — were often bigger and better fed than their wild counterparts. But over time, these stocks became more domesticated and possessed fewer survival skills, according to a 1996 report by the National Academy of Sciences.
Today, some hatchery fish still pose problems for wild stocks. Indeed, many of the fish that end up on the spawning grounds are hatchery strays.
The Western Washington state hatchery system is undergoing an extensive independent review to help determine what operational changes should be made.
An independent review of the Columbia River system released earlier this year concluded that it is still not clear how much damage hatchery spawners may cause to wild stocks.
Therefore, reviewers said, deliberate efforts to push hatchery salmon into spawning grounds should be attempted only on a limited, experimental basis.
State and federal biologists involved in hatchery restoration are quick to acknowledge that some intact wild stocks should be left alone. But they are convinced that hatcheries can help other wild runs.
"A lot has changed in the last 15 years," said Rob Jones, a National Marine Fisheries Service official who helps monitor the region's hatchery restoration efforts. "There are a lot of new things being done."
At a Cle Elum hatchery operated by the Yakama Nation, for example, young fish are trained how to avoid predators in special raceways.
Merganser ducks, caged by chicken-wire coops, are lowered into the raceways and devour all the young salmon within reach. "Initially, they (the salmon) are pretty naïve and hang around, but they learn pretty quick" to avoid the ducks, said David Fast, the hatchery's research manager.
And Hood Canal hatcheries, back in the '90s, launched a kind of salmon-rescue mission of troubled wild summer runs. Initial results of the 12-year program are encouraging.
Wild-run counts have rebounded from fewer than 1,000 returning fish to more than 30,000 this year — all now protected under the Endangered Species Act, according to Tim Tynan, a National Marine Fisheries Service official involved with the restoration.
Kalama River hatchery
The Kalama River is a different story. This is the site of the state's oldest hatchery, which first began releasing salmon back in 1895. The decades of interbreeding have blurred the line between hatchery and wild stocks of fall chinook. Yet the tangled genetics of the Kalama fish have not stopped the wild fall chinook from gaining a listing as threatened under the federal Endangered Species Act.
Kalama biologists, however, are unable to tell the difference between most of the hatchery and wild fish. They manage the entire run as if it were of a single stock, taking several thousand salmon to the hatchery each year for brood stock, and letting the rest spawn in the river.
But the eggs in the river face an uncertain future. Even in a pristine river, salmon redds are at risk from winter floods that destroy salmon-rearing habitat. But on the Kalama, the decades of logging, farming and development have intensified the runoff cycles and upped the risk of the flooding.
And diking and channeling have made the Kalama straighter, so the young fish that do emerge will have less marshland and fewer side-channels to provide food and refuge from predators.
Without improving the river conditions, restoring the wild runs will be a difficult task. Hatcheries can keep flushing their fish into the spawning grounds, but once they stop, the runs could eventually falter or fail.
"You can plant fish in the streams and get them to come back — but the problem is their survival over generations," said Lichatowich, the biologist and author.
Still, at least this year, with ocean conditions prime, the river returns are an impressive sight. Salmon pack the deep green holes. Eager fishermen cast with flies, bait and lures.
"It's been phenomenal," said Wayne Orzel, owner of Mahaffey's on the River, a tackle shop along the Kalama. "The good old days are now."
Hal Bernton: 206-464-2581 or email@example.com
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