Surprise Shrimp Under Antarctic Ice

At a depth of 600 feet beneath the West Antarctic ice sheet, a small shrimp-like creature managed to brighten up an otherwise gray polar day in late November 2009. This critter is a three-inch long Lyssianasid amphipod found beneath the Ross Ice Shelf, about 12.5 miles away from open water. NASA scientists were using a borehole camera to look back up towards the ice surface when they spotted this pinkish-orange creature swimming beneath the ice

Scientists trying to catch a glimpse of what the underbelly of an ice sheet in Antarctica looks like got the surprise of a lifetime when they found a shrimp-like amphipod and a jellyfish thriving in the subfreezing dark water.

Six hundred feet below the ice where no light is found, scientists had believed that nothing more than microbes could exist. But when the NASA team lowered a video camera to the depths to look around, they watched as a curious 3-inch-long Lyssianasid amphipod came swimming by and snagged on to the camera cable. Scientists also pulled up a tentacle from what they believe to be a jellyfish.

NASA ice scientist Robert Bindschadler, who will be presenting the findings and a video at an American Geophysical Union meeting Wednesday, told The Associated Press, “We were operating on the presumption that nothing's there.”

The video may inspire experts to reassess what they know about life in harsh environments. It did have scientists reflecting on the possibilities that if shrimp-like creatures can thrive below 600 feet of sea ice, why not in other hostile places like Jupiter’s frozen moon Europa?

“They are looking at the equivalent of a drop of water in a swimming pool that you would expect nothing to be living in and they found not one animal but two,” said biologist Stacy Kim of the Moss Landing Marine Laboratories in California.

“This is a first for the sub-glacial environment with that level of sophistication,” said microbiologist Cynan Ellis-Evans of the British Antarctic Survey, who was intrigued by the finding. He noted that there have been similar findings of complex life retreating in ice shelves, but nothing this deep under the ice before. He did say that it was possible they were just passing through from far away and don’t live there permanently.

But Kim, a co-author of the study, doubts it. The site is at least 12 miles from open seas. It is unlikely that the two creatures swam from a great distance and were randomly filmed in such a small area, she said.

However, what puzzled scientists was what food source could be available there. While some microbes can make their own food out of chemicals in the ocean, the amphipod and the jellyfish cannot, Kim said.

The key question is ‘How do they survive’? “It's pretty amazing when you find a huge puzzle like that on a planet where we thought we know everything,” Kim said.