A giant Antarctic sleeper shark was filmed for the first time at a depth of 490 metres in the Southern Ocean. The cold waters near the South Shetland Islands usually surprised experts who thought sharks don’t live there. The shark was estimated to be 3 to 4 metres long. Alan Jamieson, researcher and director at the Minderoo-UWA Deep-Sea Research Centre, said, “We went down there not expecting to see sharks because there’s a general rule of thumb that you don’t get sharks in Antarctica.” He added, “It’s not even a little one either. It’s a hunk of a shark. These things are tanks.” The water temperature was just above freezing at 1.27 degrees Celsius. A skate, related to sharks, was seen on the seabed and appeared calm as the larger shark passed by. This was not surprising since skates are known to live this far south. According to Peter Kyne, a conservation biologist at Charles Darwin University, this is the first recorded sighting of a shark so far south. He noted that climate change might push sharks into colder Antarctic waters, but data is limited because the region is hard to study. Jamieson said sleepers sharks could have lived here unnoticed for a long time. The shark stayed around 500 metres deep because it is the warmest water layer in the area, amid colder and fresher layers above and below. The region’s ocean is layered due to melting ice and dense cold water. The researchers believe Antarctic sleeper sharks feed on dead whales, squid, and other animals on the ocean floor. Cameras only work in the Antarctic summer months, leaving most of the year unexplored. Jamieson commented, “This is why, I think, we occasionally come across these surprises.”