Watch Extremely Rare Footage of Giant Squid With 'Thick Arms': 'Terrified'

While scuba diving in a bay off the western coast of Japan, Yosuke Tanaka and his wife Miki came face to beak with an enormous sea monster: an 8-foot giant squid.

The animal was swimming near the surface of the water in an area with lots of seaweed. "It's very rare to see them alive," Tanaka told Newsweek.

Footage captured by Yosuke shows the giant squid swimming just below the water line with its long tentacles stretched out behind it. "I was so excited," Yosuke said. "And I felt terrified because it had very thick arms—if I was caught, I would not be able to escape."

Tanaka and his wife run a scuba-diving business called Dive Resort T-style in Toyooka City, Hyogo Prefecture, in western Japan. In a blog post on their website, Tanaka said that he was alerted to the rare creature by a nearby ferryman.

Based on its size, Tsunemi Kubodera, an honorary researcher at the National Museum of Nature and Science in Tokyo, told NHK news that the squid was likely around 1 or 2 years old.

Tanaka said that, despite measuring over 8 feet, the squid was fairly small for this species. Jon Ablett, senior curator of mollusks and cephalopods at London's Natural History Museum, previously told Newsweek that the giant squid can grow to up to 39 feet.

"It is thought that the colossal squid, Mesonychoteuthis hamiltoni, may reach an [even] larger size in terms of mass and possibly also in length than that of the giant squid, although no one has found a fully mature specimen," Ablett said.

Despite their tremendous size, giant squid are notoriously difficult to find, which makes it difficult to estimate how many of them there are. Our best guess comes from studying the stomach contents of sperm whales, the major predator of the giant squid.

"A study by Clyde Rober and Elizabeth Shea estimated up to 131 million giant squid are fed upon by sperm whales each year," Ablett said.

Although the squid can be found in all of the world's oceans, they are more commonly found in the waters around New Zealand and Japan, the North Atlantic and in the water around Africa. But because of their elusive nature, our understanding of this species is fairly limited.

"I feel very lucky to have met him even once in my life," Tanaka said. "I hope that this will shed some light on the mystery of this squid and I hope many divers visit this area."

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