Nahuelito, the “Patagonian plesiosaur”, as it is sometimes called, is a lake monster reported in the Nahuel Huapi Lake of Argentina and Patagonia. Like Nessie, the Loch Ness Monster, the Argentine creature is named after the lake she resides in.
The huge lake covers over two hundred square miles at the base of the Patagonian mountains, a perfect site for a watery cryptid, variously described as a giant serpent or a huge hump with rough skin.
Head like a snake’s. Its neck 9 feet long. Multiple humps. Behavior: Surfaces only when the lake is calm also makes distinctive breathing sounds.
First sightings in 1910 when George Garret worked at a company located near the Nahuel Huapi. After navigating the lake and about to disembark, he could see a creature about 400 meters away, the visible part of which was between 5 and 7 meters long and protruded about 2 meters above the water.
Commenting on his experience with local people, Garret learns similar stories told by the indigenous people.
But Garret’s sighting in 1910 was only made public in 1922, when he recounted it to the Toronto Globe newspaper and echoed in the international press, thus motivating himself to organize the first expedition to search for Nahuelito.

The international search for the Nahuelito began in 1922, when Clementi Onelli, the Buenos Aires Zoo director, was sent accounts of large unknown tracks and matted weeds on shore at the same time locals claimed to be seeing a monster in the middle of the lake.
They said the creature had a swanlike neck. A subsequent expedition, led by zoo superintendent Jose Cihagi, produced nothing of consequence. Writing in the July 22, 1922, issue of Scientific American, Leonard Matters remarked that the plesiosaur, “if it ever existed, appears to have fled to parts unknown.”
More recently, in 1960, the Argentine Navy was said to have chased an unidentified underwater object in the lake for 18 days, without being able to identify it, which some people related to this alleged creature.
Jacques Barloy has written of sightings from the 1970s, and John Kirk’s “In the Domain of the Lake Monsters” (1998) cites several reports from the 1990s.
On February 16, 1978, Sra. Rumboll saw the long neck of an animal leaving a wake.
In 1988, photos of the Nahuelito were published in a magazine of the Río Negro newspaper. These were taken at a short distance with an analog camera, in which the object was near the coast of Bariloche.
“It is not a log of whimsical shapes. It is not a wave. El Nahuelito showed his face.” said a man, who did not reveal his name, in a letter he left with the photos.
Jessica Campbell and others observed an animal with multiple humps swimming in the lake on January 1, 1994.
Two years later, on 1996, Campbell saw the animal twice in one afternoon, once when it swam directly toward her as she sat on some rocks.
On April 17, 2006 the local newspaper El Cordillerano reported that an anonymous photographer dropped off two pictures of what he said is Nahuelito with a note that read:
“It is not a twisted tree trunk. It is not a wave. Nahuelito has shown his face. Lake Nahuel Huapi, Saturday April 15, 9 o’clock. I’m not giving out my personal information in order to avoid future headaches”.
Though little known elsewhere, the Naheulito is something of a cryptozoological celebrity in South America. This mysterious inhabitant of one of the world’s most beautiful lakes is still being seen frequently.