Dolphins stranded in shallow water in San Antonio Bay, Argentina Hundreds of stranded dolphins in Argentina appear to have become trapped while escaping hungry orcas in a tragic lose-lose situation. Videos shared on social media and citizen science platforms have helped scientists unravel the mystery behind two deadly mass stranding events in recent years, says Magdalena Arias at the National Scientific and Technical Research Council of Argentina. “This doesn’t mean predators are always the cause of mass strandings, but it suggests that predator-prey interactions may sometimes trigger these events – particularly when combined with factors such as coastal geography, tides and the strong social behaviour of dolphins,” says Arias. Marine mammals have been getting stranded in mass mortality events for millions of years, but scientists still debate why they happen. Possible explanations include human disturbance, toxic algae, infectious diseases, disorientation, overpopulation, natural disasters and group hunting efforts that take a wrong turn. Some research teams have suggested that stranded pods might have been fleeing from predators. But that is difficult to document, as hunts cover …