The presence of a sleeping shark in the Southern Ocean, filmed 490 meters deep by members of a scientific expedition, calls into question our knowledge of squala’s habitats. Until then, we thought they were not supposed to live in this corner of the world.
The scene may seem innocuous to an inexperienced eye. However, it is of great importance. In January 2025, an underwater inspection camera, used by an Australian expedition in Antarctica, immortalized a sleeping shark. At nearly 500 meters deep, in a desert setting immersed in darkness, the gray squale slowly passed by the device. An unexpected appearance in a region where, according to a rule widely accepted by the scientific community, sharks were not supposed to exist.
« We didn’t expect to see any sharks there at all. And it wasn’t a small one. It was a hell of a piece. These animals are real tanks, » researcher Alan Jamieson told The Associated Press on Wednesday, February 18.
A historical first
Filmed off the South Shetland Islands, near the Antarctic Peninsula, in the waters of the Southern Ocean, the animal was at first glance between three and four meters long. The camera belonged to the Minderoo-UWA Deep-Sea Research Centre, an institute specializing in deep-depth exploration based in Crawley, Australia. At this depth, the water temperature was close to zero, at 1.27 °C, say the authors of this discovery. It is not the only cartilaginous fish observed during this sequence, since a ray is also visible in its perimeter. She remains motionless on the seabed during the passage of the shark, seems indifferent to her cousin.
Never before had a shark been observed in the Antarctic Ocean, recalls Alan Jamieson. Peter Kyne, a conservation biologist at Charles Darwin University, in turn confirmed that no shark had ever been seen « so far south » and that these first images were « really significant ».
Other congeners present?
The issue of climate change is a backdrop. The researchers believe that ocean warming could push some species to explore colder waters, such as those in the southern hemisphere, but data is sorely lacking in this isolated region of the globe. Sleep sharks, known to move slowly, could also have been present for a long time in Antarctica without anyone noticing, says Peter Kyne.
The shark photographed was kept at a depth of about 500 meters, at the level of the hottest layer of water among a superposition of layers stacked to the surface. The seabed then descended to much deeper waters.
The Australian center team adds that other sharks, like him, could live at this same depth, feeding on whale carcasses or giant squid that have fallen into the abyss. Problem, cameras capable of monitoring these areas are rare and only work a few months a year, from December to February. « The remaining 75% of the time, no one is watching. That’s why, sometimes, we still come across surprises, » concludes Alan Jamieson.
source : geo
