A new study has provided the strongest evidence yet that naval sonar is responsible for the stranding and death of large groups of beaked whales. Researchers working near the US Navy's Atlantic Undersea Test and Evaluation Center found that the whales stopped making their clicking and buzzing calls during live sonar exercises and fled the area, the BBC reports. The response was the same as it was to simulated killer whale calls, a key predator of the creatures.
The frightened whales quickly moved out of the way of the sonar calls, and, in some circumstances, "they are just unable to get out of the way and this ends up with the animals stranding and dying," the lead researcher says. "We showed that the animals reacted to the sonar sound at much lower levels than had previously been assumed to be the case," he explained. "Perhaps the most significant result from our experiments is the extreme sensitivity of these animals to disturbance." (More beaked whales stories.)