On Friday morning more than 150 pilot whales were found stranded on Hamelin Bay in Western Australia. While some were dragged back to sea by cranes, most of the whales died on the beach.
Local wildlife authorities have been taking samples from the dead whales to try and determine what caused the mass stranding. Nicola Hodgins of marine mammal conservation group Whales and Dolphins Conservation says whales tend to stick together, which could explain why so many are often found stranded in one area. “This happens unfortunately many, many times,” she told National Geographic. “If one is sick, then the other whales don’t want to leave their side. The other animals end up beaching as well because they don’t want to leave them.”
Underwater noise could be another reason whales become beached. Sonic booms caused by seismic activity from military sonar or gas and oil exploration can be piercing to whales and dolphins, Hodgins explains. “[The sound] disorientates the animals. They end up trying to ‘run away,’ and the energy it takes to do that is potentially debilitating.”
In other instances, whales that are injured or old sometimes beach themselves when seeking shallower waters to help them breathe.