The Giant Penguin is a cryptid, allegedly seen in Florida during the 1940s. The legend has no scientific merit and is at least partly documented to have been a hoax.
In 1948, several people reported finding large, three-toed animal tracks at Clearwater Beach in Florida. Later, more tracks were found along the shore of Suwannee River, 40 miles (60 kilometers) from the ocean. A young couple also reported having been harassed by a large creature that had risen from the ocean.
Later that year a giant penguin was allegedly sighted at distance. The huge bird was described as 15 feet (4.5 meters) tall, and havingalligator-like feet. During this same period, people in a boat off the Florida gulf coast reported seeing an extremely large penguin-like bird floating on the water. These incidents were reported in several newspapers. Later that year, another huge, penguin-like bird was allegedly seen from an airplane on the banks of the Suwannee River in northern Florida. The sighter, zoologist Ivan T. Sanderson, declared that the creature was a giant penguin that had somehow been driven away out its natural habitat.
On April 11, 1988, St. Petersburg Times reporter Jan Kirby revealed that the penguin hoax had been perpetrated by Tony Signorini and Al Williams, a locally known prankster who died in 1969. Signorini stated they had been inspired by a photograph of fossilized dinosaur tracks, and showed the reporter the huge penguin feet made of iron used in creating the tracks. The other sightings are either also hoaxes or based on observer error; some sharks might resemble a giant penguin when seen from above under adverse conditions, for example.
There were numerous prehistoric species of gigantic penguins (such as Pachydyptes ponderosus and Anthropornis nordenskjoeldi; see also Palaeeudyptinae). These are known from considerable amounts of fossil remains, but all such lineages certainly became extinct some 25 mya at latest; they were never encountered alive by humans, and just barely were contemporaries of the earliest hominids.
Actual prehistoric megafaunal birds only occurred in South Pacific and Cape Horn ocean waters. No ecological niche is known to have existed anywhere which could have ensured their post-Paleogene survival, as their known habitat and the neighboring regions are known to have been continuously inhabited by other penguin species and similar competitor taxa ever since.
Giant penguins based on the fossil finds also appear in Jules Verne's novel Journey to the Center of the Earth, and in At the Mountains of Madness by H. P. Lovecraft. In the latter case, they are found in a fictitious Antarctic underground setting and their presence is given a comparatively plausible evolutionary explanation.