Videos Released Of Deepest Fish Ever Filmed

Scientists from Japan and Britain have released the first photos and videos of the deepest-living fish ever to be caught on film. Groups of the fish, known as the liparid, were recorded nearly five miles beneath the surface of the Pacific Ocean.

The creatures were found at least 4.8 miles down in the Japan Trench — the deepest that cameras have ever filmed. Previously, the record for the deepest fish filmed was four miles.

Often called the tadpole fish, sea snail or snail fish, the liparid must have a number of adaptations that enable it to withstand miles' worth of water pressure and virtual darkness, according to Monty Priede, director of Oceanlab at the University of Aberdeen in Scotland, which is leading the research.

"They don't have any air spaces in them, so being squashed by the water isn't a problem," Priede told NPR's Andrea Seabrook. "But if you subject muscles or nerves to this kind of pressure, they stop working — electrical conduction along nerve cells stops working. So these fish must have all kinds of invisible adaptations at the molecular and ultrastructural level, which we hope to study in the future if we catch more specimens."

Although there is no light that deep in the ocean, the liparid do have eyes located in the front of their heads, Priede said.

"And they'll be using those eyes to look at bioluminescence — flashes of light produced by animals in the deep sea," he said. "The lights of our camera are so bright that these animals cannot interpret that as anything. Their eyes won't be able to detect that light, so essentially as far as 'looking' in the way we do, they're blind."

Priede said the fish are still able to catch and eat food, such as shrimp, but they do so by sensing vibrations in the water.

The research team, a collaboration between Aberdeen and the University of Tokyo, used what they call a "free-form lander" to submerge the video camera. Priede said the device looks similar to a lunar lander.

"Except we just drop it off the ship — we don't need any rocket engines," he said. "Then after the mission is finished, the ship comes back again and you're not sure if you're going to get anything until the lander pops up on the surface, and then it can replay the videos.

"The guys on board the ship were astounded last week when they saw these fish down there," Priede said.

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