Salmon fins snipped at a good clip by automated machines

By Erik Robinson
Underwood, Washington (AP) 3-08

In the highly engineered environment of the modern Columbia River, even the Pacific Northwest’s iconic salmon is produced in assembly line fashion.

Lately, the mechanization has reached a new level of efficiency at the Spring Creek National Fish Hatchery. A series of three state-of-the-art machines make it possible for the hatchery to clip the adipose fin of every finger-sized tule fall chinook salmon.

That’s 15 million fish.

“It wasn’t feasible to try to hand-mark that number of fish,” said Larry Marchant, who manages the hatchery for the U.S. Fish & Wildlife Service. “Mass-marking trailers really speeds that process up.”

Three of those automated trailers, priced at about $1.1 million each, now supplement the work of 40 temporary employees working two shifts to snip off the adipose fins of as many fish as possible. The goal is to make sure every fish produced at Spring Creek is marked so that fishermen in the river and on the ocean will be able to distinguish finless hatchery-raised “keepers” from their wild-spawned cousins, which they throw back so they can continue toward their spawning grounds.

Biologists generally see the fatty fin, on the fish’s back just in front of the tail, as something akin to the human appendix.

It is quickly and efficiently snipped in the automated trailers.

Using sophisticated computer-aided photography, the machine sorts the sub-yearling fish by length. Pneumatic gates divert the fish in tubes toward one of six snipping lines. Each fish then slides down to the end of a tiny chute, where an automatic clipper precisely clips the fin.

“The success rate is extremely high, and mortality is extremely low,” Marchant said. “Essentially, there’s no mortality that we see.”

Even better, the automated trailers turn out 90,000 fin-clipped fish every day.

That’s about twice the rate accomplished by two shifts of a dozen workers who must spend the day hunched over watery work stations for $11.01 an hour.

Federal fishery managers believe the Rube Goldberg-style automated contraption is the wave of the future for two essential reasons: The tenuous state of wild-spawning native fish, combined with the need to feed the voracious appetite of commercial, sport and tribal fishermen for salmon and steelhead raised in hatcheries.

“It’s the only way you’re truly going to be able to manage effectively,” Marchant said.

Federal fish managers originally constructed the Spring Creek hatchery in 1901 to offset overfishing that had by then taken a serious toll on the once-abundant runs of wild salmon returning to the Columbia River basin. In later years, a flurry of federal dams further eroded wild salmon populations.

These days, with several stocks of salmon already extinct or headed that way, federal authorities are taking care to sort out the last vestiges of wild native fish from the ones produced in hatcheries.

The bulk of the adult fish returning to spawn in the Columbia River are now raised in hatcheries, but it’s only been in the last few years that hatchery managers have tried to mark all of the smolts released for their journey to the ocean.

“It’s a classic example of how slow things are to change,” said Larry Cassidy, a Vancouver resident and former state Fish and Game commissioner.

U.S. Rep. Norm Dicks, D-Wash., three years ago added funding for the trailers into the federal budget.

“When you get to a point were you have mass marking on the whole fishery, you really have the problem quite well solved,” said George Behan, spokesman for Dicks.

Tribal groups disagree.

Their fundamental disagreement with the mass-marking philosophy is a key reason, besides a lack of money, that hatchery managers have resisted marking all hatchery-raised salmon and steelhead for so long. Tribal fishermen, who by treaty are allowed to use traditional nonselective dipnets in the river above Bonneville Dam, say that increasing the rate of selective harvest in the lower river and ocean would effectively reduce the number of fish arriving above the dam.

“We’d like to see more of those fish come back for in-river fisheries, especially above Bonneville,” said Stuart Ellis, harvest management biologist for the Columbia River Inter-Tribal Fish Commission in Portland.

Ellis criticized the cost of the trailers and the $1.5 million needed annually to operate them. In addition, he said, the mass-marking program skews the calculation fishery managers have historically used to divvy up harvest between commercial, sport and tribal fishermen.

A better solution, Ellis said, is to organize harvest by run timing and location.

“You can actually do OK like that, and you don’t have to invent all these wild schemes for these marked selected fisheries,” Ellis said.

 

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