Giant squid are no longer a fish tale

A future scientist who attended the Vernon Area Library's Science Explorers program asked, "What is a kraken?" The library is in Lincolnshire.

Two stories tall, yet practically invisible, the kraken is a legendary giant squid.

It seems improbable that this mammoth sea creature with eyeballs bigger than dinner plates, eight arms, two feeding tentacles and an oversized beak has rarely been seen.

At one time these squids were just fish tales, sailor stories, and the villains in Norwegian and Greenlandic folklore, and while mysterious today, a few lucky marine biologists can say they've seen the kraken alive and in their deep sea homes.

A live giant squid wasn't captured on film or in photos until 10 years ago, when scientists on a research vessel in Japan hooked a 24-foot squid and brought it to the surface. That incident drove researchers to find resources and develop technology that would bring them face-to-face with a kraken - alive and underwater.

Marine biologists finally figured this out by using a special e-jelly camera that can function at extreme depths and a specially designed submersible with a marine scientist at the wheel.

Giant squid live in the very deepest, darkest depths of the ocean where there is very little light except for bioluminescence, a chemical in sea creatures that creates light. When being attacked, many animals at these depths trigger bioluminescent chemicals as a way to attract even larger predators to the scene in an effort to break free.

Giant squid use bioluminescence to see predators. Photophores in their eyes are bioluminescent glands that contain symbiotic bioluminescent bacteria. These headlights make it easier to see their nemesis, the sperm whale, in the dark, deep sea.

Pictures of these gargantuan creatures give them the appearance of having only one eye since the eye placement is on each side of the body. These creatures have monocular vision, so the eyes work separately to decode their environment, unlike human eyes that work together and see binocularly.

These features - the bioluminescent headlamps and binocular vision - help the squid see predators at a distance despite very low light levels and help them to coordinate their feeding tentacles, which can shoot out as far as 33 feet to snag a snack.

Edith Widder realized these giants were so hard to see because equipment used to dive a half mile underwater was too noisy and drove them away. Researchers used lights to see in the dark depths and to take pictures, but these bright headlamps also repelled the underwater animals.

In a 2013 TED Talk, Widder, whose Florida-based Ocean Research and Conservation Association aims to clean up oceans and waterways, devised a system of red lights that would be almost invisible to underwater animals but sufficient to capture them on film. She added a feature that would make the camera look like a bioluminescent snack and hopefully lure a giant squid. She also redesigned submersible instrumentation and noise levels so motor noise was at a minimum.

The results paid off - the long search to see giant squid alive and in their own environments was over, a giant advancement in marine science.

It was off the coast of Japan where Widder and the research team experienced this momentous event. Experts estimate by observing the beaches where giant squid parts wash up that these creatures live all around the world except in tropical and polar areas.