Why do whales strand themselves?

After thousands of years, we still don't really know why mass whale strandings happen. Almost 500 whales beached themselves on a remote stretch of Tasmania's west coast this week, and we'll probably never get a good explanation for it. Today, we go knee deep on Tasmania’s beaches and hear the best theories about the phenomenon. Featured: Dr Olaf Meynecke, research fellow, Griffith University Tom Mountney, volunteer whale rescuer