According to legend, the first European account of Champ was made in 1609 by French explorer Samuel de Champlain — the founder of Québec and the lake's namesake — who spotted the creature as he was fighting the Iroquois on the bank of the lake. However, in actuality no such sighting was recorded, and it has since been traced back to a 1970 article.
Long before that, however, two Native American tribes, the Iroquois and the Abenaki, talked of such a creature and celebrated its existence. The Abenaki gave it the name "Tatoskok."
Sightings varied over the years, but the next most important sighting came in 1883 when Sheriff Nathan H. Mooney claimed that he had seen a “…gigantic water serpent about 50 yards away”  from where he was on the shore.
He claimed that he was so close that he could see “round white spots inside its mouth” and that “the creature appeared to be about 25 to 30 feet in length”. Mooney’s sighting led to many eyewitnesses coming forward with their own accounts of Champ sightings. Mooney’s story predated the public Loch Ness controversy by 50 years. Since that report, there have been more than 240 recorded sightings.
The reason some scientists believe that Champ may be a plesiosaur like “Old Nessie” is because the two lakes have much in common. For example, like Loch Ness, Lake Champlain is over 400 feet deep. Also both lakes were formed following the Ice Age about 10,000 years ago and both lakes support fish populations large enough to feed a supposed sea or lake monster (Krystek 1).
Champ became so popular that the late P. T. Barnum, in the early 19th century, put a reward of $50,000 up for a carcass of Champ. Barnum wanted the carcass of Champ so that he could include it in his epic World’s Fair Show (Krystek 3). Sightings continued through the 19th and 20th centuries, but no remains or any other physical evidence has ever been recovered.
The most remarkable photo of a Champ appearance was taken in 1977, by amateur photographer Sandra Mansi. The photo appears to show what is said to be a plesiosaur-like neck and body sticking out of the lake.
According to Mansi, she heard her children screaming and turned toward the shallow water by the shore where they were playing. Seeing the creature, she took the photo as her fiancée, Anthony, grabbed her children. Mansi had several photo experts examine the picture and they concluded that the picture has not been tampered with in any way.
Those experts also stated that they believe it to be a living creature . Mansi later showed the photo, which is similar to the famous "Surgeon's photo" of the Loch Ness Monster, to Joseph W. Zarzynski.
Zarzynski—founder of the Lake Champlain Phenomena Investigation and a Wilton, New York Social Studies teacher—took the photo to Gorge Zug of the Smithsonian Institute’s Department of Vertebrate Zoology. Zug states that the creature in the photo does not resemble any creature or animal living in Lake Champlain, that he knows of.
The creature has become so famous and so much a part of life in Vermont and New York, that both states passed laws to protect the monster. The creature was put on the endangered species list only as a precaution. The law will protect the creature if anyone eventually does come upon a Champ. Quebec has not placed Champ on its list of endangered animals.
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