History’s Great Mythical Sea Monsters

Generally, the advancement of science leads to the dispelling of myth. It turns out the Sun is not actually Apollo riding his chariot across the sky after all. But it was only really in the 19th century that palaeontology took off and brought the domain of the dinosaurs to public consciousness, many centuries after monster sightings across the world and its history.

Knowledge that giants once existed fuels speculation that they may yet still. While the lion’s share of Earth’s land has been seen and studied, the majority of the ocean remains unexplored. We have rather literally only scratched the surface. There is of course danger in the flagrant filling of the blanks of natural history, but with so much unknown, inexistence is no more certain.

With not only better access tools but the advent of video recording equipment, humans are now better equipped than ever to confirm or dispel our most enduring monster myths. Technology and the knowledge it brings certainly have a sobering effect, as most of our monster sightings have been reduced to misinterpretation and misdirection. But sometimes science brings confirmation, and when misinterpretation turns out to just be exaggeration, we can forgive and still be left with something that captures our imaginations.

Get Kraken


Certainly one of the more celebrity monsters is the Kraken, which is essentially thought to be a massive octopus that terrorized ships off the coast of Iceland and Norway. Putting ships through the ultimate boat exam its tentacles could reach up and around the top of the tallest mast and pull the ship under, equally dangerous was the large funnel it left behind as it dove deep, leaving whatever remained of a ship to swirl and flush away.

Some seafarers speculated the width of the Kraken to be well over a mile. While that’s certainly fun to imagine, even the blue whale, today’s biggest known animal, has never been recorded over 110 feet long. But as monsters go, the Kraken has the most likely real world cousin.

Some believe experiences of the Kraken to be not of an octopus, but of a giant squid, which can grow to as much as 40 feet in length. The larger colossal squid can grow to about 45 feet, but is generally restricted to Antarctic waters , and as such is unlikely to have been the subject of a Kraken eye-witness account. Specimens of giant squid have not only been recovered around the world, but there are confirmed attacks by giant squid on ships, as they tend to be more aggressive than equivalent octopi.

45 feet is certainly far less than a mile, but also certainly quite monstrous. While the Kraken itself may be pushing the boundaries of reality too far, the existence of the giant squid, caught live on film for the first time as recently as 2006, shows that the world’s creatures may be more monstrous than we think.

Liquid Snake

Equally slimy but far less satisfying on the existence front is the sea serpent, which you have likely seen gracing the corner of an old map. As with the Kraken, there are numerous tales of ship attacks, but they far less substantiated, not even validated in a milder form as with the giant squid.

Rather, sea serpents are more often the subject of distant sightings of serpent-plausible shapes on the water’s surface, namely in the form of a long, proportionally skinny neck and reptilian head sticking out, with potential humps behind.

From a mythological standpoint, they are extremely popular, most famously in the form of Jörmungandr, the serpent nemesis of Thor. The love-child of Thor’s brother Loki and the jotun woman Angerboda, Jörmungandr was said to be long enough to encircle the globe.

The multi-headed Hydra of Greek myth can also be said to fall under this serpent class. This monster, defeated by Hercules who buried its immortal head under a massive rock, is potentially inspired by giant squid sightings.

The biblical Leviathan is also rather serpentine, with a Kraken-like size that is said to be able to cause tsunamis. As with the Hydra, the Leviathan is placed firmly in the realm of myth, and is often used as a catch-all term for any tremendously massive sea creature.

Whoa Nessie

While not strictly a serpent, plesiosaurs-like sea monsters like Nessie, the famous Loch Ness Monster, create a similar spotting experience. The majority of its body remains submerged, with only a neck above the water line, trailed by the curved hump of its back.

There are have been many attempts throughout the 20th century to ascertain whether or not Nessie exists, most conclusively in 2003 with the BBC’s “Searching for the Loch Ness Monster”, which, using sonar and satellite technology capable of mapping granularity at the level of a small buoy, conclusively demonstrated Nessie to be pure myth.

Indeed, there are numerous ways to create the neck-and-hump(s) shape, including the following:

  • Basking sharks
  • Floating debris
  • Whales
  • Oarfish

Fish Women

An entire class of sea monster is the half-person half-fish half-breed. These creatures are often meant to symbolize the man/beast duality of a human being, and are typically female, although mer-men grace the pages of myth as well. Charming as Disney’s Ariel may have been, mermaids are frequently represented as manipulative and malicious.


At best, the mermaid forgets that humans can’t breathe underwater as they’re taken below. At worst she intentionally drags men down and drowns them.

Closely related to mermaids are the three Sirens of Greek myth, whose songs control the behavior of men to destructive ends. While typically bird-women and not so much fish-women, many references to sirens in mythology are indeed aquatic.

Not surprisingly, these hybrid creatures are completely unsubstantiated, with explanations for sightings sometimes being attributed, as in many monster-sighting cases, to squid or squid-like creatures, for example, in the case of the sea monk.


Looking beyond the mythical archetypes, there is always the potential of seeing something entirely new. The Montauk Monster of 2008 is a good example, as there have been three sightings now of the beast - whatever it is. Unlikely to be “real”, whatever that means, it is as of yet unconfirmed as a hoax of any kind.

Monster Hoaxing, Monster Hunting

Bottom line, monsters intrigue us, which is why so many tricksters are tempted to produce headline-catching hoaxes. Nessie has been the target of numerous fakeries herself, with carcass and bone planting and simulated footprints.

That said, with knowledge of dinosaurs that once were and creatures like the colossal squid which remain, and with the invention and improvement of new tracking and recording technologies, the evidential hunt for the sea monsters that have captured our imaginations for centuries will likely continue for centuries more.

Related Articles