Video: The white whale that actually 'talked' to humans
A voice telling divers to get out of the water at a marine life centre has been identified as that of a 15-year-old white whale called NOC.
For years, researchers at the National Marine Mammal Foundation in San Diego, California, thought they heard voices when under water.
When they realised that nobody had given anyone a command to leave the water, they looked to the whale as the source of the sounds.
They started recording and studying the noises that NOC made, and what they found and published in Current Biology today as amazed the marine world.
It is the first known case of a whale trying to talk like a human.
NOC began speaking in the 1980s after spending seven years in close contact with researchers at the facility. His "speech" reduced after four years and stopped altogether once he reached adulthood.
He died five years ago after 30 years at the National Marine Mammal Foundation.
Scientists say the whale changed the way he produced noises in order to make his voice sound more familiar to his keepers.
National Marine Mammal Foundation president Sam Ridgway told news.com.au: "We do not claim that our whale was a good mimic compared to such well known mimics as parrots, but it is an example of a whale learning human speech patterns.
"Our observations suggest that the whale had to modify its vocal mechanics in order to make the speech-like sounds. Whale voice prints were similar to human voice and unlike the whale's usual sounds. The sounds we heard were clearly an example of vocal learning by the white whale."
Some researchers believe NOC wanted to make contact with his human friends.
Dr Patrick Miller, lecturer at St Andrews University's school of biology, told the Daily Telegraph: "It is sort of like babbling speech in humans – when children first learn to speak they are making a whole range of different sounds driven by their desire to communicate with people around them.
"It is probably something of a stretch for the animal to make these sounds but given the context of their captivity and close contact with humans, presumably they were very motivated to do it."
Here NOC's '"talking voice" below: