Very cool! Years ago I read about the loneliest whale in the world. It could only communicate at 52 hertz, or above a frequency other whales couldn't hear. I think scientists think it finally passed on because they aren't picking up its unique sounds anymore.
"THE LONELIEST WHALE is a cinematic quest to find the “52 Hertz Whale,” which scientists believe has spent its entire life in solitude calling out at a frequency that is different from any other whale. As the film embarks on this engrossing journey, audiences will explore what this whale’s lonely plight can teach us — not just about our changing relationship to the oceans, but to each other. Executive Produced with Leonardo DiCaprio and Adrian Grenier and directed by Joshua Zeman."