Snorkeler Drags "Sea Serpent" Carcass to Shore

Photo: Catalina Island Marine Institute

Jasmine Santana, a science instructor with the Catalina Island Marine Institute, was snorkling off the California coast when she made a very strange discovery: the carcass of an 18-foot long oarfish.

These are very odd fish.

They have long narrow bodies with a spiky dorsal fin that runs the length of their body, making them look like just a head with a really long tail. They swim vertically in the water column. They can reach lengths of 36 feet and hold the Guiness Book World Record for being the largest bony fish (whale sharks are the largest fish, but they are cartilaginous, not bony). Despite their size, they have no teeth and feed on tiny zooplankton, crustaceans and squid by filtering them out of the water.

The oddest thing about this discovery is that oarfish are so very rarely seen. (Well, I suppose the fact that a Ms. Santana dragged the 400-pound rotting carcass to the surface to get her picture taken with it seems pretty odd too–but not for a science instructor!) Their normal habitat is about 3,000 feet down in the deep sea. To see one, living or dead, at the surface, is exceedingly uncommon. In fact, the first time the species was ever recorded alive on film was in 2001.

No one knows what happened to this particular oarfish, causing it to die and end up so close to shore. In fact, very little is known about this species in general. We don't even know their population numbers or whether or not they are endangered.

What we do know is that this is a species that might be responsible for legends of sea serpents. It's not hard to imagine ancient sailors spotting one of these giants on one of their very rare visits to the surface and thinking it a sea monster. Oarfish are not the first real animal to inspire a fantasy creature. The legend of the kraken is based on real-life giant squid species, also normally only found at great depths. Mermaids are likely based on dugongs, a thinner and more lithe relative of the manatee.

But here's the thing: the more you know about real wildlife, the more you realize that truth can be stranger–and more amazing and beautiful–than any fictional tall tale. There really are sea serpents. They’re called oarfish.

I love mythological creatures, but an unfortunate side-effect of focusing on fantasy instead of science is that it can make people fear perfectly harmless wildlife. None of these so-called sea monsters pose any threat to people.

While we don’t know much about the oarfish yet, we do know that manmade threats like pollution, aggressive overfishing, and climate change are putting a huge strain on the world’s oceans and the sea creatures that live in them.

Here's a video showing the first footage of a living oarfish. Seeing the living fish in action is even stranger than the the pics of the dead one.

Special thanks to my National Wildlife Federation colleague Miles Grant for researching this post. You can follow Miles on Twitter.