Watch: First-ever sleeper shark sighting in Antarctica’s freezing waters leaves scientists stunned

In a discovery that has surprised marine scientists, researchers have recorded what is believed to be the first-ever sighting of a shark in the freezing waters of the Antarctic Ocean, challenging long-held assumptions that sharks do not inhabit the region’s frigid waters.The sleeper shark, identified as Somniosus antarcticus, was filmed in January 2025 by a deep-sea camera operated by the Minderoo-UWA Deep-Sea Research Centre near the South Shetland Islands off the Antarctic Peninsula.The shark, estimated to measure between 3 and 4 metres (10 to 13 feet) in length, was spotted at a depth of around 490 metres (1,608 feet), where temperatures hovered just above freezing at about 1.27°C.Researchers had not expected to encounter sharks at such southern latitudes. “There’s a general rule of thumb that you don’t get sharks in Antarctica. And it’s not even a small one, it’s a substantial animal. These things are like tanks,” said Alan Jamieson, founding director of the research centre at the University of Western Australia.The footage shows the bulky predator moving slowly across a barren seabed, while a skate, a close relative of sharks, remains motionless nearby, seemingly undisturbed by its presence.Experts say the sighting is significant because there had been no confirmed records of sharks living so far south in Antarctic waters. Peter Kyne, a conservation biologist at Charles Darwin University who was not involved in the expedition, described the discovery as “quite significant,” noting that the rare footage offers valuable insight into the region’s largely unexplored deep-sea ecosystem.Scientists believe sleeper sharks may have long existed in Antarctic waters but remained undetected due to the extreme environment and lack of observation equipment. Research cameras at such depths can only operate during the Antarctic summer, from December to February, leaving the ocean largely unmonitored for most of the year.Jamieson explained that the shark was likely maintaining its depth because it corresponded to a relatively warmer layer in the ocean’s stratified water column. Antarctica’s ocean waters form distinct layers due to temperature and density differences, influenced by melting ice and deep cold currents.The elusive predators are thought to feed primarily on carcasses of whales, giant squid and other marine animals that sink to the ocean floor.Scientists say climate change and warming oceans could potentially influence the range of marine species, though it remains unclear whether environmental shifts played a role in this sighting. Researchers believe more such discoveries could emerge as deep-sea exploration technology improves.