Bolten said one of the whales may have been sick, or their sonar may have led them into the shallow harbor and they couldn't find their way out again.

Examinations of stranded whales show evidence of hearing damage, internal bleeding, and symptoms similar of the "bends" that human divers experience when ascending from dives too rapidly. Since whales rely heavily on their hearing and making sounds to communicate, navigate, mate and find prey, even if they aren't injured by sonar, that sonar can disrupt their ability to survive.