Cadborosaurus willsi, affectionately regarded as 'Caddy,' is a cryptid that lives in the waters off the Pacific Northwest coast of North America.  Caddy received its name in the 1930s by way of one Archie Willis, a newspaper editor in Victoria, British Columbia, Canada. 
Caddy has been reported over three hundred times since the 1930s,  and at least twenty of those reports occurred in the 1990s.  The reports range from Alaska to Oregon, with the majority of the sightings around Vancouver Island and the Northern Olympic Peninsula. 
Cadborosauruses range in size from fifteen to forty-five feet long.  They have been described as snakelike  or serpentine.  A Cadborosaurus has a horse- or camel-like head and long neck, with vertical humps along its body. Cadborosauruses have a pair of side flippers and spikes on their tails. 
Sightings of Cadborosauruses have occurred over the centuries. Many indigenous groups have their own legends specific Cadborosauruses.
The most notorious evidence for the existence of the Cadborosaurus appeared in 1937 at Naden Harbor. A unique specimen pulled from the stomach of a whale, later dubbed the 'Naden Harbor Carcass,'  gave hope to many cryptozoologists and Caddy enthusiasts. Unfortunately, the specimen was dismissed as a premature Baleen Whale. 
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