Nature & Environment

Deep Sea Squid Lures in Prey with Swimming Tentacles (Video)

Catherine Griffin
First Posted: Sep 03, 2013 11:53 AM EDT

The deep sea is home to some strange and fantastic creatures. There's the anglerfish with its bright lure, the colossal squid with its teeth-like barbs and the frill shark with its prehistoric appearance. Now, scientists have uncovered a new sea creature and its method of luring in prey.

Most squids have eight arms and two longer "feeder" tentacles. The tips of the tentacles, which are often broader and armed with suckers or hooks, are known as "clubs." These squids hunt by rapidly extending their tentacles and then grabbing their prey with their clubs. They then pull their hapless victims toward their mouths, devouring the creatures.

Yet this latest squid, named Grimalditheuthis bonplandi, uses an entirely different strategy. It's a relatively slow swimmer with a weak, gelatinous body--a stark contrast to the sleek, muscled body of the giant squid. In addition, its tentacles are long, thin fragile and too weak to capture prey.These tentacles don't have any suckers, hooks or photophores to help. And yet somehow, some way, this creature manages to feed itself.

In order to find out a bit more about this creature and its feeding strategies, the researchers examined video from underwater robots known as remotely operated vehicles (ROVs). This allowed them to watch this creature in its native habitat about 3,000 to 6,500 feet beneath the surface of the waves. In addition, the scientists dissected over two dozen preserved squids from various collections.

When the ROVs first approached these squid, they hung motionless in the water. Their eight arms were spread wide and their two long, thin tentacles dangled below. These two tentacles fluttered and flapped with the motions of thin, fin-like membranes on the clubs as they appeared to swim on their own. In fact, almost all of the squids' motions gave the impression that their clubs were small, swimming animals independent of the rest of the squids' bodies.

Therein lies the way these squids hunt. It's possible that the motion of the clubs may cause smaller squids and shrimp to approach close enough to investigate. It's very likely that the larger squid then traps its prey in its arms. Essentially, the squid acts like a giant, underwater Venus flytrap.

The researchers have yet to see the squid actually capture its prey, though. Yet this particular method seems very likely considering the squid's size and shape. The scientists plan to continue combing the depths of the ocean, which might reveal a little bit more about this and other unusual creatures.

The findings are published in the journal Proceedings of the Royal Society B: Biological Sciences.

Want to see the squid for yourself? Check out the video below, courtesy of YouTube.

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