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Legend of the Lahontan Trout

Betsy Mason

This 18-pound Lahontan trout was caught recently in Pyramid Lake. The lake was once a big destination for anglers, and Native Americans hope those days will return.

In the bottom of a dusty display case in the Nevada State Museum in Carson City, the carcass of a 41-pound fish sits decaying. Caught in

1925, this gigantic stuffed trophy is all that remains of the legendary Lahontan cutthroat trout.

Or is it?

The legend begins 14,000 years ago, when parts of eastern California, southeastern Oregon, and much of what is now Nevada lay beneath the waters of Lake Lahontan. Cutthroat trout from the Pacific Coast began migrating into the Lahontan Basin. Then about 8,000 years ago, the climate became more arid. The lake shrank, and the pioneering trout were cut off from their original coastal territory. The landlocked fish began to adapt to their new habitat of interconnected lakes and rivers.

And adapt, they did. The hardy fish thrived in remnants of Lake Lahontan such as Pyramid Lake, 35 miles north of Reno, Nevada. There, Lahontan cutthroat trout that spawned in the Truckee River grew to weigh an incredible 60 pounds or more. Local Paiute Indians came to depend on them as a significant source of food. And in the twentieth century, sport anglers including Clark Gable and President Herbert Hoover flocked to the lake for the experience of catching the mammoth fish.

But demand for Truckee River water to irrigate farms and slake the thirst of Nevada’s growing cities eventually caught up with the fish. In 1905, the completion of Derby Dam outside of Wadsworth, Nevada, effectively blocked its spawning run. By 1940, unable to reproduce in the wild and under pressure from intense sportfishing, the giant trout disappeared from the lake.

However, we might not have seen the last of the Pyramid Lake trout. The fish may have been transplanted to other locations by fishermen hoping to save them from extinction. And populations of smaller subspecies, with genes that date back to the original coastal cutthroat migrants, survive in isolated rivers and lakes throughout the Great Basin.

In October 1970, the Lahontan cutthroat trout (Oncorhynchus clarki henshawi) was declared a federally threatened species. The official protection of the Endangered Species Act unleashed both the political will and the funding necessary to revive the legend. Biologists hope that, by carefully breeding its surviving relatives, they can bring the giant trout back. The United States Fish and Wildlife Service and the Pyramid Lake Paiute Tribe have joined forces in an effort to resurrect the Lahontan in Pyramid Lake. The federal government alone will devote tens of millions of dollars to the project over the next 20 years. And the drive to return the trout to its native waters may ultimately result in an even broader benefit—the restoration of the lower Truckee River.

Pyramid Lake is a stunning desert oasis on the eastern edge of the Sierra Nevada. Its deep blue waters and pristine shoreline stretch for miles. The pyramid-shaped rock formation that gave the lake its name catches the afternoon sunlight on the eastern shore. The lake lies entirely within the Paiute Indian reservation and consequently has escaped the intense development that enveloped its sibling, Lake Tahoe. Only the small Paiute town of Sutcliffe interrupts the wilderness that rules the lake’s perimeter.

Biologist Brian Niewinski, laboratory and resource manager for the tribe’s fishery, has a look of fatherly pride on his face as he leans over a tank full of eight-month-old trout. They are a week away from being released into the lake. “I’m hoping one of these guys will grow to be 15 pounds or more,” he says with a smile.

Since the 1970s, the tribe has been cultivating trout to rival the legendary proportions of their ancestors. Recreational fishing is a big source of income for the Paiutes, bringing in about half a million dollars a year, according to Niewinski. “Our goal at the fishery is to maintain and improve recreation on Pyramid Lake. We want to get the fish bigger,” he says. “We want to please the angler.”

While size may be important to the tribe, Fish and Wildlife is interested in something else: genes. Charged with recovering the species, the federal agency aims to breed the most genetically correct form of the trout—the one whose DNA is closest to that of the legendary game fish that once inhabited the lake.

Lisa Heki heads the Service’s Lahontan recovery effort. While investigating the Paiute tribe’s fish breeding program, Heki found historical anecdotes suggesting wild trout in streams near Pilot Peak, Utah, had been transplanted directly from Pyramid before the original giant disappeared. Because the Pilot Peak watershed has remained free of rainbow trout that could potentially interbreed with the Lahontan, she suspected that this strain was a better proxy for the old Pyramid Lake trout than the one currently growing in the hatcheries.

Looking for hard evidence, Heki hired biologist Jennifer Nielsen, a U.S. Geological Survey fisheries supervisor, to identify which strain represents the closest match to the giant trout of yesterday.

The Nevada State Museum would not give researchers permission to extract DNA from the 1925 museum specimen. So Nielsen tackled the problem from another angle. Using techniques that are able to detect subtle genetic variations, she compared all the existing populations of ancestral Lahontans and identified two genetically distinct groups. One comprised populations from the western Lahontan basin, including fish from Summit Lake on Donner Summit, and Pyramid Lake hatchery stock. The second consisted of fish from Edwards Creek, Macklin Creek, and Pilot Peak, all in the eastern basin.

But which genetic resumé deserves to repopulate Pyramid Lake? Several lines of evidence suggest Heki’s hunch about the Pilot Peak fish was right. The genetic similarity among the isolated eastern stream populations is quite high and much greater than that of the western lake populations. This supports the idea that these fish are direct descendants of trout transplanted out of Pyramid before the big fish were gone. What’s more, Nielsen found that the Pyramid Lake hatchery fish are not pure Lahontan.

But the Paiute tribe wants the biggest possible fish, regardless of its pedigree. “They call our fish mongrels,” says tribal member Elwood Lowry, of Fish and Wildlife’s attitude toward the strain of trout growing in the Paiute hatchery. The tribe admits the hatchery fish are not genetically identical to the original Lahontans. But Niewinski has his doubts about the Pilot Peak fish as well. He argues that because there isn’t any DNA from the original Pyramid Lake trout available, there is no way to unequivocally determine which modern strain is the closest genetic match. In the absence of a smoking gun, he thinks the robust, lake-adapted strain the tribe is currently raising is the best fish for the recovery effort. The tribe is convinced that the Pilot Peak fish will not survive as well or grow as large as the fish they have been carefully breeding over the years.

But just finding the right genes might not ensure the return of the enormous trout. While all the necessary raw materials may reside in the Pilot Peak fish, the original Lahontan’s extraordinary size could have been driven primarily by environmental adaptation. The Pyramid Lake environment that existed before the dams were built was probably a critical factor. Any realistic hope of bringing back a self-sustaining population depends on restoring the habitat that the fish and their admirers used to enjoy.

Every spring before Derby Dam was built, the huge fish fought their way up the Truckee River to spawn. Their return created quite a spectacle. The trout “were a mainstay of the Indian people,” says Tom Trelease, a lifelong resident of the Reno area who remembers the original lake trout. “They would catch them when they were spawning, dry them in the spring, store them, and eat them in the winter months.”

The trout were also a source of income for the Paiutes in the 1930s. “My grandmother used to buy them from the Indian people who would go around town in their Model-T’s and sell them,” says Trelease. “They were nice big fish. They were two to three feet long.”

Today, eleven major dams and many smaller barriers block the Lahontan’s historic spawning run along the Truckee River to Lake Tahoe. But the problem runs deeper. The dams and agricultural water diversions have drastically altered the physical characteristics of the river. For instance, each of the dams stops floodwaters from clearing sediments out of gravel beds essential to trout spawning. Rapid regional population growth means that dam removals and increases in river flow are unlikely to happen soon.

Another problem lurking in the Truckee is competition from nonnative trout. Brown trout outcompete cutthroats for food and resources, while rainbow trout will interbreed with them.

Despite these obstacles, Heki remains optimistic about the Lahontan’s recovery. “Yes, it can be done and quicker than people believe—if there is cooperation,” she says. A number of groups are trying just that. The Paiute tribe, state agencies, several biologists, and conservation groups such as Trout Unlimited have joined Fish and Wildlife to devise a recovery plan. After many rounds of debate, they finalized a plan in early spring. The team will focus its immediate efforts toward restoring the trout’s habitat and helping spawning fish bypass the physical barriers such as those on the main stem of the Truckee River. In these areas, state agencies have agreed to stop stocking nonnative trout to make room for the Lahontan.

Although Fish and Wildlife and the tribe haven’t yet been able to agree on a single strain of fish, the federal agency thinks it can convince the Paiutes to back the Pilot Peak trout. Heki plans to test their growth potential as lake fish by introducing them to smaller lakes in the region. She hopes that within the next five years or so, these trials will prove to the Paiutes and other skeptics that the fish are fit for larger lakes such as Pyramid Lake, Walker Lake, and Lake Tahoe. She plans to phase in the fish gradually as they gain acceptance. “I think the support is starting to build,” she says.

All the research, planning, arguing, negotiating, time, and money involved in the recovery effort may seem like a lot to go through for a fish. But in Nevada, the Lahontan cutthroat trout isn’t merely a fish. It is a native trout species in a state passionate about fishing. It is part of state history and a symbol of the wilderness that once dominated the region.

And Nevada stands to get more than just the return of a native son out of all this blood, sweat, and science. Any long-term plan to reestablish a self-sustaining population of Lahontans in Pyramid Lake is dependent upon the restoration of the Truckee River, one of the state’s most prized stretches of water. If Nevada brings back the Lahontan, the mighty trout will bring back the river.

Already land managers are improving survival and spawning conditions for the Lahontan. Dams and other river barriers are getting fish ladders or detour passages, and artificial spawning channels are being created to provide a better environment for trout eggs. To restore the original appearance and flow patterns of the river, federal and local government agencies are working to remove obstacles such as small irrigation inlets, returning river sections to their original meandering paths, and encouraging streambank restoration with native plants. These improvements have the added benefit of reducing flood risk while helping the fish.

“It will take a long time to heal the river, but I think it will respond if given half a chance,” says Heki, who thinks the trout has a rosy future. “Twenty years down the road we could have 20- to 30- pound cutthroat trout running the river right through downtown Reno.”


Betsy Mason is a geologist and freelance writer.