Something strange started happening in early 2023 in the waters off south-western Europe, where the Mediterranean sea meets the Atlantic ocean. Orcas began slamming into the sides of fishing and sailing vessels. The killer whales then dived underneath to locate and destroy the rudders used to steer the boats. Once finished, the orcas departed, leaving shocked crews and thousands of dollars of damage behind. Some of the attacks were over in a matter of minutes, but others lasted hours. It’s very unusual behaviour for this particular mammal, but orcas are under a lot of threat from man-made hazards. Factors like underwater noise pollution, overfishing, toxic waste and climate change to name a few are making orca life extremely difficult. Could all of this have caused this change in behaviour? Contributors: Billy Heaney, zoologist, wildlife tour guide and presenter Dr Jeremy Kiszka, professor of biology at Florida International University in Miami Hannah Strager, marine biologist and director of exhibitions at the Whale Museum in Norway Nicola Hodgins, researcher with the global charity Whale and Dolphin Conservation Presenter: Charmaine Cozier Producers: Anoushka Mutanda-Dougherty, Jill Collins, Matt Toulson Editors: Tara McDermott and Tom Bigwood Researcher: Matt Toulson Sound designer: Nicky Edwards Production co-ordinator: Jordan King Image: An orca showing its teeth (Credit: Marcos del Mazo/LightRocket via Getty Images)