(Independent) -- The researchers were studying a 14-year-old female killer whale named Wikie, who was well-trained and had been taught how to copy behaviours in a previous study.

Wikie was recorded mimicking English words like “hello”, “bye bye” and “one two”, as well as the name of her trainer, Amy.

“Killer whales use their blowhole to make noises, almost like speaking out of your nose, so we were not expecting it to be perfect,” said Dr Jose Abramson, a researcher at the Complutense University of Madrid, who led the study.

“But we were surprised by how close it was.”

The scientists wanted to understand how capable whales are of imitating noises, so they could understand how whales learn in their natural habitat.

In addition to human sounds, Wikie was exposed to noises made by another killer whale to see if she was capable of imitating them.

The results of the experiments were documented in the journal Proceedings of the Royal Society B.

After listening to the human or whale sound, Wikie was requested to reproduce them by her trainer saying “do this”.

Wikie’s calf, a three-year-old whale named Moana, was taught to make five unique sounds that could then be used to test his mother.

Human sounds were thought to be suitably distant from the killer whale’s usual repertoire of noises that they would provide a more advanced test of her ability to imitate.

To determine whether the original sounds and Wikie’s versions matched, the researchers asked human judges to decide, and then ran computer algorithms to provide a more objective assessment of the similarities.

Imitating vocal sounds in this way is a key component of language, and the ability to do so is rare in mammals besides humans. 

Despite their intelligence, other primates are not generally capable of such imitation. 

However, cetaceans – the mammal group that includes whales and dolphins – are known to be highly adept when it comes to vocal imitation. Both bottlenose dolphins and beluga whales have been observed copying noises they are exposed to.

In the wild, different killer whale groups demonstrate unique vocal “dialects”, and they have been documented copying noises made by other species.

“They have even been known to imitate bottlenose dolphins and sea lions,” said Dr Abramson.

The scientists thought the ability of Wilkie to imitate new noises may provide some insight into the process by which whales imitate the sounds they hear in the wild, and acquire dialects.

Though the study was confined to one individual, Dr Abramson said it was a good indicator of what these whales are capable of doing.

 “We are looking at what these animals can do,” said Dr Abramson.

“There is evidence of vocal imitation in the wild, and this provides experimental evidence that supports that.”

(Photo: independent)