Killer whales have destroyed the rudders of more than 600 boats off the coast of Portugal, Spain and Morocco. Now researchers believe they know why the orcas are attacking.
Most attacks have taken place off the coast of Gibraltar and southern Spain, but recently the first known incident in British waters occurred, with an orca ramming a yacht off Shetland.
Social media is awash with stories of sailors being rammed by orcas or being chased by sea animals in what appears to be either a bit of fun or intimidation
The killer whales circled the Dutch yacht before attacking it. The assault carried on for several heart-stopping minutes as the team approached the Strait of Gibraltar.
Dr Wim Rutten, a 72-year-old Dutch retired physicist was sailing from Lerwick to Bergen, Norway, when the orca rammed into the stern of his boat. Pictured is an orca attack off the Iberian Peninsula.