Native Trout Are Returning to America's Rivers- page 3 | Science | Smithsonian

Native Trout Are Returning to America's Rivers

Native trout are returning to America's rivers and streams, thanks to new thinking by scientists and conservationists

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Behnke is heartened that government agencies and conservation groups such as Trout Unlimited show a new appreciation for the importance of genetic diversity and improved habitat, both of which are emphasized in the National Fish Habitat Action Plan. The plan, announced in March 2006 by the U.S. Fish & Wildlife Service and a partnership of state agencies and conservation organizations, will scientifically identify the leading threats to fish species and offer guidelines for their recovery and conservation, with a focus on protecting streams and rivers for fish. The project is modeled after the largely successful habitat restoration plan launched for waterfowl in the 1980s.

In some Western states and in most national parks, biologists and wildlife managers believe that the future health of trout populations will also be enhanced by less emphasis on hatchery-raised fish and more on habitat improvement. In Montana, which depends on visiting anglers for many of its tourist dollars, the state department of Fish, Wildlife & Parks stopped stocking its rivers and streams with hatchery-raised fish three decades ago. The idea was to preserve the variety of Montana's wild trout, which had been compromised by decades of competition and inbreeding with hatchery fish, which tend to be less hardy and less wary than their wild cousins. Hatchery trout, which still form the basis of state programs in much of the heavily populated East, are also expensive to raise and to transport to streams, where they are quickly caught by anglers or dispatched by other predators. Less than 1 percent of such fish survive from one season to the next, according to Behnke. "Everybody thought we were crazy when we stopped stocking hatchery fish," says Tom Palmer, information bureau chief of Montana's innovative fish and wildlife agency. "Now it's all wild. We get bigger and better fish that way. They are more resistant to disease, and they survive longer."

Palmer's comments seemed pertinent on a recent September morning, when the season's first snows salted the mountains and I floated down the Madison River in a drift boat prospecting for big brown trout. "Why don't you throw your line under that bank?" said Brian Grossenbacher, an old friend now working as a fishing guide in Bozeman, Montana. I plunked a fuzzy green fly made of feathers and synthetic yarn in that direction. It drifted down through the clear current, and a trout lunged for it. He yanked hard, hooked himself, thrashed through the weeds, splashed across the river's surface and finally came close enough to net. The fish weighed about three pounds, his butter-colored sides sprinkled with vermilion spots. We quickly returned him to the river, where, with a flick of his tail, he melted into the gloom. It was a brown trout. Though not native to Montana, he was as wild as a one-eyed jack, his ancestors having been born, bred and tested in the Madison over many generations. In that time the browns had taken over the province of westslope cutthroat trout, which were surviving in the river system but in smaller numbers than the now-dominant browns and rainbows.

Which fish had the stronger claim? As we slid through the mountains, I posed this question to Grossenbacher: "Should the Madison be poisoned to bring back the natives?"

"Stupid idea!" he barked. "We've got a river full of wild fish here. People come from all over to catch them. There's been enough mucking around already," he said, closing the subject. "Cast there to the right—and don't flub this one."

Within an hour or so, we had floated past the mouth of Cherry Creek, a Madison tributary that flows from media tycoon Ted Turner's Flying D Ranch, recently the focus of a long-running and acrimonious legal dispute. In question was whether the state, in partnership with Turner, could poison portions of the creek to kill nonnative brook trout, rainbows and hybrids and to create a reserve for a genetically pure strain of westslope cutthroat trout. A federal appeals court had ruled in favor of the restoration, and the poisoning had begun.

"Because the area is large," says Palmer, "it will support a large population of westslope cutthroat trout that will be more likely to survive in a changing environment over the long term." To establish havens for the fish, his department plans ten such conservation areas in the Missouri-Madison River drainage, where cutthroats once inhabited 1,200 miles of the river system; in their genetically pure form, cutthroats occupy just 8 miles of that system today.

For the moment, nobody proposes killing the huge population of nonnative fish that make the Yellowstone and Madison rivers so popular for fishermen. It would be technically impractical—piscicides are not effective on big, brawling rivers—but, more to the point, it would be politically impossible, given the rivers' importance to Montana's economy.

One of the nation's prime destinations for traveling anglers, Montana collects $422 million from fishermen each year. They might themselves be considered invasive, descending in large groups summer and fall, shuffling through the Bozeman airport with their rod tubes while gasping for oxygen in the thin mountain air.

With part of the money Montana collects from such visitors, and with funds saved from closing most of its hatcheries, the state is emphasizing habitat improvement, so that its rivers will have cleaner water, less erosion, better spawning beds and better cover from streamside vegetation—all of which make them more productive. Repairing a trout stream may involve nothing more elaborate than planting a few willows or cottonwoods to stabilize the banks, or fencing out cattle to keep them from trampling the shoreline and fouling the water. In other cases, where years of poor land use have seriously degraded a trout stream, more extreme fixes are required.

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