The hideous beast was discovered by two horrified nurses after their dog Sam pulled it from the murky water.
The gruesome animal has baffled experts and triggered speculation that it could be similar to the famous "Montauk monster", which was washed up in New York two years ago.
Pictures were posted on a local website after nurses Joseph Murrillo and Kelly Hick found the unidentified creature while they were hiking on the Kitchenuhmaykoosib Inninuwug reservation in Canada.
The mutant animal is bald on its face, head and feet and has tusk-like teeth.
The grisly online snaps came with an explanation that read: "The dog jumped in the lake and pulled the creature to the rocks and dragged it out for the hikers to see and these are the photos they took.
"The creature's tail is like a rat's tail and it is a foot long."
"There are experienced hunters that have been around for decades. They have 'trap lines' which refer to as hunting grounds. And in all these years they have never seen anything like this."
Another said: "That certainly is a face only a mother can love. It looks like some sort of otter, weasel-type thing."
It has been compared to the monster found in Montauk in 2008. It was never officially identified.