A team of geologists planning to gather sediment samples from the sea floor, set up a camp on the Filchner-Ronne ice shelf, a large body of floating ice in the Weddell Sea. They drilled a hole in the ice and dropped a camera through it hoping to get mud samples from more than 300m below the ice sheet.
But to their surprise the camera hit a rock covered with stationary animals instead of mud! These animals are suspected to be sponges and barnacles or hydroids. Some of them had round bodies while some seemed like tiny thread-like organisms.
Scientists were not expecting these creatures at such depth under the ice sheet at all. Sea animals like fish and crustaceans have been found beneath the Antarctic ice in the past, but this is the first time that immobile animals like these rock hugging creatures have been found. The only animals found were the ones who moved around to gather food.
The stationary filter-feeding sponges stay at the same spot and sustain themselves by grabbing the food that passes by. What’s puzzling is that these rocks are situated 600-1,500 km away from the nearest phytoplankton source. By the time they float and travel to this sunlight deprived area, most of them would’ve been consumed by other animals or sunken to the ocean floor. But surprisingly the sponges still get enough fuel to grow and survive.
Right now very little is known about these animals and certain questions still remain unanswered like- since how long have they been there (some Antarctic sponges can live for 1000 years or more), how often do they feed- once a year, once a decade or once a century?
However, this discovery is significant as it proves how adaptable and diverse Antarctica's harsh environment is, and also how much more there is to explore in the depths of the ocean!