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Gentle Giant: Massive and Mysterious Oarfish Caught on Video


It’s the mysterious animal that most likely gave rise to sea serpent myths.

The oarfishat first resembles a pencil as it stands at attention in the murky ocean depths. But then it begins undulating, and this 25-foot-long silver ribbon of an animal starts moving along. But even then, the oarfish never gets horizontal.

Oarfish, or Regalecus glesne, are known as the King of Herrings, according to, which supplies detailed technical information on fish species.

Mark Benfield, a researcher at Louisiana State University, was part of a team studying the effects of the Deepwater Horizon oil spill in 2011 when the remotely operated vehicle spotted it swimming 364 feet down and moved into position to record. The result is some of the longest, most detailed footage ever shot of these mysterious creatures.

In a rare instance, there appears to be a parasitic crustacean clinging to the fish’s dorsal fin, said Undeterred, the fish swims by controlling movements with precise undulations of its dorsal fin, Benfield told “Paddle-like appendages” at the bottom of their pelvic spines help them maintain balance and swim upright, he said.

“The fish swim with their head upright and their tail hanging beneath them, and can easily move backward and forward and up and down quickly,” said. Hence the moniker oarfish.

The footage was taken in 2011 but surfaced, so to speak, when it was compiled with other videos in a report for the Journal of Fish Biology in June. The oarfish is the longest bony fish on the planet, according to, and it has been known to reach 50 feet.

U.S. Navy

U.S. Navy men show off an oarfish.

Oarfish are little known, but they drew attention a few years ago when about 20 of them became stranded on Japanese beaches just before the devastating earthquake and tsunami in March 2011. Scientists have not proven that they knew what was about to happen, but they are not ruling it out.