In 1948, what looked like giant three-toed animal tracks appeared, imprinted in the sands of Clearwater Beach, Florida. The prints – about 35 centimeters (14 inches) long and 28 centimeters (11 inches) wide – appeared to emerge from the sea, taking 1.2-1.8 meter (4-6 foot) strides along the beach for a few miles, before whatever creature had made them returned to the sea once more.
Before long, sightings of strange creatures were reported. Students at the Dunedin Flying School claimed that they had seen the beast – which looked like a furry log with a boar's head – swimming in the water, while a couple strolling along the beach claimed they had seen a gigantic creature waddling near the water before disappearing into the sea.
The tracks were investigated by the police, for reasons that are fairly unclear, who concluded that "if a prank, it was one of the most masterful ever perpetrated" in the area. Another investigator – British biologist Ivan Terence Sanderson, who later strayed into pseudoscience and cryptozoology – conducted his own investigations, as the tracks continued to be found over the next decade. It was at this point that it was suggested that the culprit of the footprints was a 4.5 meter (15 foot) tall giant penguin.
“The tracks invariably followed the gentlest gradients even at the cost of considerable meandering and, secondly, that they meticulously avoided all possible snags and obstacles even down to the smallest bushes," Sanderson wrote of his investigation. "These are, one and all, typical animal traits.”
Sanderson ruled any possible hoax as unlikely, arguing in favor of the much more plausible scenario that a gigantic penguin was roaming the beach completely unnoticed.
“That any man or body of men could know so much about wild animal life as to make the tracks in just the manner that they appear, but that they also should be able to carry this out time and time again at night without anybody seeing them or giving them away," he wrote, "is frankly incredible.”
Flash forward to 1988, where local man Tony Signorini posed in his big metal penguin shoes, confessing to the elaborate prank.
Signorini and his friend (and boss) Al Williams, who died in 1969, had seen a photo of dinosaur footprints in National Geographic, inspiring them for their big decade-long prank. The two created gigantic three-toed metal feet, before attaching them to tennis shoes. The two would regularly take out a small row boat just off the shore, before one of them donned the 14-kilogram (30-pound) shoes and walked up the beach, before meeting the boat further up the coast.
To create a long enough stride for their fictional creature, Sigorini would stand on one leg and swing the other, building up momentum for a jump. To guarantee that their efforts wouldn't be missed, the footprints would often be reported by one of their friends the following day.
After his death in 2013, Signorini's family made sure his obituary included that "Tony was famous for being 'The Clearwater Monster,' a hoax that made national news."