Photo: Sam Mansfield
Finding a way that allows humans to communicate with whales has become the obsession of wildlife film-maker Tom Mustill. His first encounter with a whale was very nearly his last.
In 2015 he was out whale watching off the coast of California, when a humpback breached his kayak, tipping him and his companion into the water.
Since then Tom Mustill has wanted to understand whales, if possible to learn how to communication with them.
So he went in search of researchers who could help him in this quest and has written about it in How to Speak Whale: A Voyage into the Future of Animal Communication.