How did you get there? What are you eating? How long have you been there? These are the questions scientists are asking themselves: They have found unknown species far below the Antarctic ice shelves. A result that, for example, raises many more questions than it answers. The news of the unknown creatures 900 meters below the ice appears in Limits of marine science.
It was during an exploration campaign for the Filchner-Ronne Ice Shelf. It is located in the southeast of the Weddell Sea in Antarctica. There they drilled 900 m of ice 260 km from the open sea in complete darkness and with temperatures of -2.2 ° C. Very few animals were observed under these conditions. However, this study is the first to discover the existence of stationary animals such as sponges. There are possibly several previously unknown species attached to a rock on the ocean floor.
“Are these the same species that we see outside the ice shelf, or are they new species? And what would happen to these communities if the ice shelf collapsed? “Asks the biogeographer.
The floating ice shelves represent the largest unexplored habitat in the Southern Ocean. They cover more than 1.5 million km of the Antarctic continental shelf. In eight previous holes, only a total area the size of a tennis court was examined.
In theory, life becomes less abundant as it moves further away from open water and sunlight. Previous studies have found some small scavengers and predators. There are fish, worms, jellyfish and krill in these habitats. However, it was expected that filter-feeding organisms that depend on food supplies from above would be among the first to disappear in the ice.
So it was a surprise. The team of geologists drilled into the ice to collect sediment samples. But it hit a rock instead of mud on the ocean floor. They were even more surprised by the video footage. They showed a large rock covered with strange creatures.
BAS geologist Dr. James Smith was part of the drilling team. He explains: “We expected to recover a core of sediment from under the ice shelf. It was a surprise: we saw that animals live in it ».
This is the first record of a community of living things on a rock in the depths of an ice shelf. The 900 unknown creatures under the ice challenge earlier theories.