Payback or play? The orcas sinking yachts

Orcas, also known as killer whales, rarely interfere with boats. But since May 2020 there have been hundreds of reports of orcas breaking rudders and even sinking yachts and boats in the strait of Gibraltar, behaviour which seems to be spreading. Michael Safi speaks to journalist and author Phillip Hoare about the theories scientists have for why this might be happening