The cougar, the closest American cousin to the African lion, may be roaming parts of the East from Canada to southwest Virginia and from Tennessee to Alabama, according to hundreds of reported sightings over the past two decades.

And, then again, it may not be.

Some naturalists say that scattered remnant populations of the cougar, Felis concolor -- also called mountain lion, panther, painter, puma and catamount -- have always existed in the East. Others say the big cat has made an extraordinary comeback after vanishing late in the last century, when it was killed off by hunters, fur trappers and by the expansion of farming. They point to many sightings reported by reliable observers.

But many wildlife biologists are skeptical about the reports, saying the chance of viable cougar populations existing in the East outside of southern Florida, where between 30 and 50 live, is slim. Other populations of the endangered cat are widespread in the American West and western Canada.

"We get one or two sightings every year that sound reasonable . . . from people manning forest fire towers, hunters, woodcutters, people who spend a lot of time in the woods, but none from scientists yet," said Steve Arthur, a wildlife biologist with the Maine Inland Fisheries and Wildlife Department. "With all the activity going on in the woods, it's hard to imagine that we have a viable panther population in the state. No one has shot one or found one hit on the road."

Mapping 'Credible' Reports

However, zoologist Donald Linzey in southwest Virginia says the mountain lion has always been in the East. For more than 30 years, he has investigated sightings in Tennessee, Alabama and Virginia. For the past 11 years, he has been keeping track of "credible" cougar sightings in Virginia, placing pins in a state map to mark areas where people report having seen one of the cats.

"What I try to do with the pins is to see if there is any clustering of the reports, and there seems to be in several areas of the state," Linzey said, adding that of the 250 reports of cougar sightings he's received, he judges that only about 85 are credible. The last undisputed cougar sighting reported in Virginia occurred in Washington County in 1882. Linzey won't disclose exact locations of current sightings because he says hunters might go there to shoot the cats. "Right now, we're working on two areas in southwest Virginia from which I'm getting several reports," he said.

Close Encounter in Virginia

One of the most intriguing sightings was reported last June by a forestry technician who has been working for the Forest Service for 34 years. Richard Hickman said his close encounter happened while he was marking wilderness boundaries in a remote part of Virginia's Thomas Jefferson National Forest, a mountainous, boulder-strewn area -- ideal habitat for the cougar.

"I saw these two small animals on top of a large, flat boulder. I thought they were groundhogs," Hickman said. "Then they both moved over to this rather large tan spot on top of the rock; when they got there they started nursing."

Hickman said he didn't think they were mountain lion cubs until he heard their mother make a loud noise.

"Both the cubs disappeared over the rim of the rock, then she immediately followed them," he said. "I thought they were gone for good. Then I approached to the lower side of the boulder and she came out. . . . She came toward me to a distance of about 15 yards. She stopped right there and froze in front of me. I'd say she was about 80 pounds to 100 pounds. I looked at that cat for about 25 to 30 minutes."

Hickman, who claims that he has seen a dozen cougars in Virginia since 1971, said that incident was the first time he has ever seen one with cubs, which would mean that the big cat is breeding in areas outside its known habitat. But two days later, when he and Linzey went to investigate the sighting, a hard rain had fallen, washing away what little evidence might have been left in that rocky terrain.

"We're looking for a good photo or a good track or an animal that has been hit by a car," Linzey said. "That's what I've been trying to track down."

The cougar is much larger than the common bobcat, which has a stubby tail, spotted legs and usually weighs between 15 and 30 pounds. An adult cougar can weigh over 200 pounds. Its tawny coat is unspotted, and its tail is long. But biologists say that it is easy for people to mistake a bobcat for a cougar.

"Some West Virginia hunters {reported} that they thought they saw a cougar and put their dogs on it and treed it," said John Organ, a Fish and Wildlife Service biologist based in Massachusetts, who monitors wildlife in a 13-state region from Maine to Virginia. "It turned out to be a bobcat, and they know what a bobcat is."

Even Organ has been fooled. "I was in a tree stand once and heard some movement," he said, adding that he caught a glimpse of a tawny-colored animal. "I thought it was a cougar, but when it came out, it was a coyote."

Coyotes are known to inhabit regions in the East where cougar sightings are claimed.

Wildlife biologists say that if people have seen a cougar in eastern areas outside of Florida, it is likely to have been a pet released by its owner or one brought from the West and let go.

"Cougars are not that elusive that we would not have some evidence if there was a viable, self-sustaining population," Organ said. "We've had no cougars legitimately sighted or captured by outdoor recreationists. They're not that hard to tree, but we haven't had any treed."

Evidence Remains Inconclusive

Outside Florida, where one or two cougars are killed each year by motorists, no carcasses of roadside kills have been found in any eastern state. Pictures taken by motorists who claimed that a cougar jumped out in front of their cars, either show a different animal or are inconclusive, and hair samples collected from areas in which a cougar was spotted have turned out to come from bobcats or coyotes.

Retired Fish and Wildlife Service biologist Robert Downing, who lives in Clemson, S.C., received a grant from the Forest Service in 1978 to investigate cougar sightings all over the South, including Georgia, South Carolina, North Carolina and Tennessee.

"We tried for five years to find some," Downing said, adding that during that time he found no evidence of mountain lions. "They're very susceptible to being hit by a car, and every day that goes by without one being hit on the road makes me more pessimistic about their existence."

Nevertheless, reports by people who claim to have seen a stealthy cougar keep mounting. A colleague of Hickman's said she saw one earlier this month within two miles of where he spotted the female and cubs. Was it the same cougar? Before the area could be inspected by scientists, another rain had fallen.