from a 2004 article by the New York Times about the loneliest whale in the world. Scientists have been tracking her since 1992 and they discovered the problem:

She isn’t like any other baleen whale. Unlike all other whales, she doesn’t have friends. She doesn’t have a family. She doesn’t belong to any tribe, pack or gang. She doesn’t have a lover. She never had one. Her songs come in groups of two to six calls, lasting for five to six seconds each. But her voice is unlike any other baleen whale. It is unique—while the rest of her kind communicate between 12 and 25hz, she sings at 51.75hz. You see, that’s precisely the problem. No other whales can hear her. Every one of her desperate calls to communicate remains unanswered. Each cry ignored. And, with every lonely song, she becomes sadder and more frustrated, her notes going deeper in despair as the years go by.