The stories were the stuff of fishing legends - cutthroat trout weighing more than 50 pounds pulled out of Nevada's Pyramid Lake in the 19th century and up until about 1940.

The Lahontan was the largest and one of the most voracious of the cutthroat trout subspecies. But it also was believed extinct, virtually wiped out by inbreeding with non-native trout, such as planted rainbows.That was before Utah Wildlife Resources Division and U.S. Fish and Wildlife Service biologists discovered a remnant population of Lahontan cutthroats in just one tiny stream in the Pilot Mountains, on the Utah-Nevada state line.

"How this fish found its way to a narrow sliver of a stream in the remote Pilot Mountains" 120 miles northwest of Salt Lake City still is an unresolved mystery, Ken Summers, a division of fisheries biologist, said Monday.

"The theory is, about 50 to 60 years ago, the Nevada Fish and Game shipped the trout around the state to stock streams and lakes," Summers said. "During one of these trips, a Nevada game warden apparently released a bucketful or so of Lahontans in that stream."

After spawning and spending a year or two in streams feeding into Pyramid Lake, just northeast of Reno, Nev., the Lahontan cutthroats would migrate to live out the rest of their lives in the spacious lake.

"In the lake environment, the trout adapted their feeding habits to become the voracious predators of smaller fish," he said. "They evolved into whoppers, the size most fishermen can only dream of."

Even though the Pilot Mountain population is few in number and the fish are small in size, because of their restricted desert environment, "they are just about all that remains of this genetic variety."

To save the species, the fisheries' biologists have spent the past two summers trying to create new populations.

This fall they transplanted 40 fish into a second stream in the Pilot Mountains, and about a half dozen fish into a private pond in the Grouse Creek area, about 40 miles to the north.

"With such a small population, we don't want to move them too far. We want to make sure there is basically the same environment. But, increasing the available habitat should cause the populations to grow," Summers said. "Eventually, we hope to get a good stock of spawners."

And dispersing the remaining endangered population would decrease the chance of the whole species being wiped out by disease or some disaster, Summers said,