The Patagonian Plesiosaur
In 1922, a prospector wrote to Buenos Aires zoo that he had seen a long-necked creature in a Patagonian lake. The zoo sent an expedition.
What was reported
In 1922, Martin Sheffield, an American prospector living in Patagonia, wrote to Clemente Onelli, director of the Buenos Aires Zoo. He said he had seen tracks and then a huge animal with a long neck, like a swan's, in a lake near Epuyén.
Onelli, who believed a prehistoric reptile might have survived, organised an expedition. The press called the animal the Patagonian plesiosaur, and the story became an international sensation.
Explanations offered
The expedition found nothing and was mocked in the press. Historians note that Sheffield was known for tall tales. Long-necked lake creatures are still reported in Patagonia, most famously Nahuelito in Lake Nahuel Huapi, but none has been confirmed.
- When
- 1922
- Where
- Near Epuyén, Chubut, Argentina
- Witnesses
- An American prospector, Martin Sheffield
- Status
- Unconfirmed
Famous cases are real, widely reported events. Each file sets out what witnesses said and the explanations that have been offered, without taking a side.