LONDON.- Millions of years before the first (alleged) sighting of the Loch Ness monster, populations of giant reptiles swam through Jurassic seas in areas that are now Britain. Known as plesiosaurs, these long-necked creatures that could grow up to 40 feet long were thought to have dwelled exclusively in oceans.

But a discovery published in a paper last week by researchers in Britain and Morocco added weight to a hypothesis that some Loch Ness monster enthusiasts have long clung to: that plesiosaurs lived not just in seas but in freshwater, too. That could mean, they reasoned excitedly, that Nessie, who is sometimes described as looking a lot like a plesiosaur, really could live in Loch Ness, a freshwater lake.

Local papers have celebrated the finding.

It “gives further credit to the idea that Nessie may have been able to survive and even thrive in Loch Ness,” said an article in the Inverness Courier, a biweekly newspaper in the Scottish Highlands.

“Loch Ness Monster bombshell,” blared a headline from Britain’s Daily Express tabloid.

“Existence of Loch Ness Monster is ‘plausible,’” read headlines in The Scotsman, The Telegraph and elsewhere, seizing on a phrase in the University of Bath’s announcement of the study’s findings.

This is not the first study to find that plesiosaurs lived in freshwater.

“This new study is simply providing additional evidence for certain members of this group living in freshwater,” said Dean Lomax, a paleontologist and visiting scientist at the University of Manchester. “We’ve always known this.”

But Nick Longrich, lead author of the study, said his team had one of the stronger cases for it because they found fossils of 12 plesiosaurs, proof that it was not just one plesiosaur that wandered into freshwater and then died there.

Georgina Bunker, a student who was a co-author of the paper, said: “The more plesiosaur fossils discovered in freshwater environments, the more this will further build the picture to explain why plesiosaurs might be turning up in freshwater environments around the world.”

Longrich, a paleontologist and evolutionary biologist at the University of Bath, said it was “completely unexpected” to find the fossil of a plesiosaur that had lived in an 100-million-year-old freshwater river system that is now the Sahara.




While on a research trip to Morocco, he was sifting through a box in the back room of a shop when he spotted a “kind of chunky” bone, which turned out to be the arm of a 5-foot-long baby plesiosaur. Longrich paid the cashier no more than 200 Moroccan dirham (about $20) after bargaining to bring down the price, and brought the fossils back to Britain for further study.

“Once we started looking, the plesiosaur started turning up everywhere,” he said. “It reminds you there’s a lot we don’t know.” (The fossils will be returned to museums in Morocco at a later date, he said.)

As the news of the study made headlines last week, some Nessie fans were hopeful. George Edwards, who was for years the skipper of a Loch Ness tourism boat called the Nessie Hunter, said that for him the new study showed how creatures could adapt to survive in new environments — and that the world is full of mysteries. Take the coelacanth, a bony fish that was thought to have become extinct millions of years ago but was found in 1938 by a South African museum curator on a fishing trawler.

“Lo and behold, they found them, alive and kicking,” Edwards said. “Anything is possible.”

Edwards said he had seen unexplained creatures in Loch Ness plenty of times: “There’s got to be a family of them.” From what he has seen, the creatures have a big arched back and no fins and are somewhat reminiscent of a plesiosaur.

But there is one detail that some Nessie lovers may have overlooked in their embrace of the plausibility of Nessie’s existence: Plesiosaurs became extinct at the same time dinosaurs did, some 66 million years ago. Loch Ness was only formed about 10,000 years ago, and before that it was ice.

Valentin Fischer, an associate professor of paleontology at the University of Liège in Belgium, said it would currently be impossible for a marine reptile like the plesiosaur to live in Loch Ness.

The first recorded sighting of Nessie dates back to the sixth century A.D., when Irish monk St. Columba was said to have driven a creature into the water. But global interest was revived in the 20th century after a British surgeon, Col. Robert Wilson, took what became the most famous photo of the Loch Ness monster in 1934. Sixty years later, the photograph was revealed to be a hoax.

But some people were not discouraged, and, ever since, throngs of tourists have traveled to Loch Ness each year in hopes of seeing the monster.

There have been more than 1,100 sightings at Loch Ness, including four this year, according to the register of official sightings.

Steve Feltham, a full-time monster hunter who has lived on the shores of Loch Ness for three decades, said the British-Moroccan study was interesting, but that it was irrelevant to his search. Ever since it became clear that the famous 1934 photo of Nessie was fake, he has stopped believing that Nessie was a plesiosaur. Plesiosaurs have to come up for air, so he figures he would have seen it during the 12 hours a day that he scans the loch. Instead, he scans the water for giant fish that look like a boat turned upside down.

“I struggle to think of any bona fide Nessie hunter that still believes in the plesiosaur,” he said. “The hunt has moved on from that.”

This article originally appeared in The New York Times.