It’s been hailed as the first evidence of tool-making among marine mammals; observations made by researchers at the Centre for Whale Research and the University of Exeter, who have witnessed killer whales bite the end off a kelp stalk and use it as a tool for a moment of shared relaxation. According to those observations, these orca have been spotted positioning the kelp between themselves and a partner and rolling the kelp between their bodies for prolonged periods of time. The behaviour was first spotted via drone footage of ‘southern resident’ killer whales in the Salish Sea, the inland waters of Washington USA. A this time, whales of all ages were observed carrying out this behaviour, possibly – researchers have positioned – to ‘strengthen social bonds and promote skin health.’ Several whales species are known to engage in something called ‘kelping’: the act of moving kelp with their heads, fins, and bodies – likely for play or, possibly, to remove parasites and maintain healthy skin. This new discovery, however (dubbed allokelping) is different because the kelp is first selected and then trimmed before being manipulated by two whales working together.