Bottlenose dolphins call out the specific names of loved ones when they become separated, a study finds.
Other than humans, the dolphins are the only animals known to do this, according to the study, published in the latest Proceedings of the Royal Society B. The big difference with bottlenose dolphins is that these communications consist of whistles, not words.
Earlier research found that bottlenose dolphins name themselves, with dolphins having a “signature whistle” that encodes other information. It would be somewhat like a human shouting, “Hey everybody! I’m an adult healthy male named George, and I mean you no harm!”
The new finding is that bottlenose dolphins also say the names of certain other dolphins.
“Animals produced copies when they were separated from a close associate and this supports our belief that dolphins copy another animal’s signature whistle when they want to reunite with that specific individual,” lead author Stephanie King of the University of St. Andrews Sea Mammal Research Unit told Discovery News.
King and her colleagues collected acoustic data from wild bottlenose dolphins around Sarasota Bay, Fla., from 1984 to 2009. The researchers also intensely studied four captive adult male dolphins housed at The Seas Aquarium, also in Florida.
The captive males are adults that keepers named Calvin, Khyber, Malabar and Ranier.
These bottlenose dolphins, however, as well as all of the wild ones, developed their own signature whistles that serve as names in interactions with other dolphins.
“A dolphin emits its signature whistle to broadcast its identity and announce its presence, allowing animals to identify one another over large distances and for animals to recognize one another and to join up with each other,” King explained. “Dolphin whistles can be detected up to 20 km away (12.4 miles) depending on water depth and whistle frequency.”