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Feature Story Photo from Mail Tribune files Hand-clipping of adipose fins could be a thing of the past if a new automated machine, which could be tested at Cole Rivers Hatchery next spring, proves effective. Machine to change future of hatcheries By MARK FREEMAN A state-of-the-art machine with minuscule knives, anvils and cameras could make a big change in how Oregonians manage, and fish for, spring chinook salmon. A new automated system that mass-marks hatchery fish could replace the old hands-and-scissors technique for clipping the fleshy adipose fins off hatchery fish. Oregon fish managers hope to test-drive the new machine this spring at Cole Rivers Hatchery, where it is expected to clip the fins and stick coded census tags in the snouts of 1.62 million spring chinook smolts. The new technology uses video-imaging, sophisticated sensors and a tiny knife-anvil system to clip and tag two 6-inch chinook fingerlings per second. It can cut its way through 50,000 fish in an eight-hour shift. Clipping that many by hand would take two months -- making such mass-marking virtually impossible statewide without an army of scissor-hands. If successful, the mechanical clipping could lead to mass-marking all the hatchery chinook released into rivers like the Rogue. Now, time and cost restraints mean just 8 percent of the hatchery fish are clipped annually, and those are strictly to estimate survival and catch rates in the ocean and inland. A river full of fin-clipped hatchery chinook could mean the Rogue's spring chinook fishing could be managed more like its steelhead angling, with catch-and-release of unmarked wild fish. "Our goal is to have all the hatchery fish marked so we can have selective fisheries as well as evaluate hatchery vs. wild stocks," says Trent Stickell, who oversees hatchery practices for the Oregon Department of Fish and Wildlife. "There's no better way to evaluate what's going on out there than being able to tell the difference between wild and hatchery stocks," Stickell says. Such evaluation is crucial on rivers like the Rogue, where the wild chinook are proposed for threatened status under the Endangered Species Act. If the chinook are listed, angling could be banned during the spring chinook runs if the hatchery fish -- which are grown and released specifically to be caught and kept -- cannot be differentiated from wild fish by anglers. "Certainly, for a stream that's going to have listed fish in it, you're going to have to find some way to differentiate hatchery and wild (chinook)," says Chuck Tracy, an ODFW policy analyst in Portland. The machine was built by Northwest Marine Technology in Oregon City, with some funding from the Washington Department of Fish and Wildlife, Bonneville Power Administration, and U.S. Fish and Wildlife Service. The small chinook swim in a tray with an inch of water in it. The machine uses the fish's own lust for water current and darkness to lure the tiny chinook into a chamber where it is briefly held in place. A camera senses where the fleshy adipose fin is on the chinook's back, triggering a small knife-anvil system that snips the fin off. Simultaneously, the chinook's head is held in place while the machine jams a coded-wire tag into its snout. More cameras check to make sure the tag is imbedded correctly and the adipose is snipped off before scooting the fish out. "It'll go so fast, the fish will hardly know what hit them," says Stan Moberly from Northwest Marine Technology. The machine is considered safer for the fish because it does not require human handling or anesthesia for the clipping to occur, Moberly says. Salmon managers watched in awe during a Friday demonstration of the prototype clipping machine near Portland . "I expected a machine that handled them like corn cobs, but they didn't," says ODFW spokesman Randy Henry. "It really goes smoothly." But the demonstration was just that -- a demonstration, Moberly says. Its first full-scale operation is set for this week in Washington, Moberly says. Only one machine has so far been built, and more are in the pipeline. Oregon hopes to either buy or lease the new technology next spring and bring it to Cole Rivers Hatchery along the upper Rogue for its first test-drive in Oregon, Stickell says. The ODFW has long wanted to mass-mark the Rogue's hatchery chinook for a variety of reasons. The system would let biologists better track percentages of wild and hatchery chinook that return as adults to the Rogue; better tell how many hatchery strays are spawning with wild fish; and devise a way anglers can continue fishing for Rogue spring chinook even if the fish are deemed a threatened species. But the cost and logistics have been the killer. Adipose-clipping and coded-wire tag imbedding by hand costs, on average, $120 per 1,000 fish. To do all the 1.62 million spring chinook in the Cole Rivers program would cost $194,400. And it would take two months to do it, with double shifts. There are not enough trained fin-clippers to do that, plus the lengthy period would force a restructuring of the tight rearing and release schedules the Cole Rivers chinook follow. The machine can clip all 1.62 million Cole Rivers chinook in 16 days, working 16-hour days. Those kinds of numbers make Cole Rivers a good choice for testing the machine. But more importantly, Stickell says, the hatchery is funded by the U.S. Army Corps of Engineers and is close enough to California so that state's fish managers can see the machine in action. The ODFW hopes to have some agreement worked out early next year with Northwest Marine Technology to bring the clipping machine to Cole Rivers, with the Corps picking up the tab, Stickell says. And if it works, the automated system will likely become standard equipment of the future in Oregon's hatcheries. "I suspect the cost of the mass-marking machines would come down," Tracy says. "In the long run, the price of labor will go up, and the cost of machines would come down." (Staff writer Mark Freeman covers the outdoors for the Mail Tribune. Call him at 776-4470.) Outdoor Journal main page Mail Tribune Copyright � interRogue & The Mail Tribune 1998, Medford, Oregon USA