Kylie, a wild dolphin in Scotland, has been seen chatting with her adopted family of harbor porpoises in their “language”, representing a remarkable world-first in cross-species communication.
After 14 years away from her species (the common dolphin, Delphinus delphis), Kylie has spent so much time around porpoises that she’s even started to sound like them. Her vocalizations include high-pitched click bursts associated with porpoises instead of the whistles and pulse calls more commonly seen in dolphins.
The cross-species communication between Kylie and her porpoise pals is the subject of a paper published in the journal Bioacoustics titled “I beg your pardon? Acoustic behaviour of a wild solitary common dolphin who interacts with harbour porpoises.” In it, researchers discuss the curious case of Kylie the wild common dolphin who lives in the waters off Scotland’s Firth of Clyde.
Kylie’s familiarity with the resident harbor porpoises prompted researchers to review recordings taken in 2016 and 2017 using a hydrophone to study her acoustic behavior. They wanted to compare the noises she made when swimming alone versus those she employed when hanging with the porpoises.
Porpoises communicate with narrow-band, high-frequency clicks, known to those in the clicking cetacean business as NBHF clicks. Dolphins on the other hand like to swim around whistling, a sound porpoises never make.
Upon reviewing the recordings, the researchers realized Kylie “definitely identifies as a porpoise,” National Geographic reports co-author on the paper David Nairn, who studies porpoises in the area, said. Not only did Kylie not whistle like other dolphins, but even when alone she could be heard using sounds that resembled the NBHF clicks associated with porpoises.
Furthermore, communication between Kylie and the porpoises had a rhythm indicative of a conversation, though exactly how much information is portrayed in these chats is unclear.
Exactly why Kylie was separated from her own pod to begin with isn’t known, but illness, injury and adverse weather have all been linked to isolated cetaceans. It seems in lieu of common dolphin pals, she’s sought interaction with the local porpoises whose vocalization characteristics have worn off on her.
It’s not the first example of vocal learning seen among cetaceans, as captive killer whales have been found to pick up the vocalizations of bottlenose dolphins when the two species were socialized.
Where can we sign up to join a cetacean crew?
[H/T: National Geographic]