A Dolphin In The Baltic Sea Was Caught Talking To Himself, Sparking Curiosity Among Researchers
A lone dolphin in the Baltic Sea has been recorded talking to himself, sparking curiosity among researchers.
They speculate that he might be expressing loneliness, potentially calling out in hopes of finding some friends.
Bottlenose dolphins (Tursiops truncatus) are known to be social animals that live in pods. But in September 2019, a single dolphin started hanging around the Svendborgsund channel, which is located south of Funen Island, Denmark, an area that is outside of the usual range of the species.
Locals know the dolphin as Delle. No other dolphins were seen nearby. Researchers deployed underwater recording devices to observe how the solitary dolphin’s presence affected porpoises near the harbor. They were shocked when they heard how noisy Delle was.
“Out of curiosity, I decided to add a recorder that captures actual sounds,” said Olga Filatova, the lead author of the study and a cetacean biologist at the University of Southern Denmark.
“I thought we might pick up a few distant whistles or something along those lines. I certainly didn’t anticipate recording thousands of different sounds.”
Over the course of 69 days between December 8, 2022, and February 14, 2023, the researchers detected a total of 10,833 sounds.
Many of them were related to communication and included 2,291 whistles, 2,288 burst-pulses, 5,487 low-frequency tonal sounds, and 767 percussive sounds.
Burst-pulses are a series of rapid-fire clicks sometimes associated with aggression. Among these noises, the dolphin also produced three distinctive whistles.
yeshaya – stock.adobe.com – illustrative purposes only
“Bottlenose dolphins have what are known as signature whistles, believed to be unique to each individual, much like a name,” said Filatova.
“If we hadn’t known that Delle was alone, we might have concluded that a group of at least three dolphins was engaged in various social interactions.”
Such sounds have traditionally been linked to communication, so there should’ve been at least two dolphins present in the area. However, Delle was completely alone.
Initially, the researchers thought the dolphin might’ve been trying to speak with a local paddleboarder, but the sounds were recorded at night, so no humans were in the water at that time.
Other experts are not totally surprised by the fact that an individual dolphin was still making sounds all by himself.
Dolphins are vocal creatures and rely on sound for activities like hunting and sensing their environment. They also use sound to communicate across long distances.
Delle may have been talking to himself, or he was producing sounds that were triggered by a specific emotion.
Another theory posits that he was calling out to attract other dolphins nearby, although this seems unlikely.
He had already lived in the area for three years, so he would know by now that no other dolphins were around.
Researchers don’t usually record solitary dolphins because no one expects them to produce any meaningful sounds, but this study has proven them wrong. There is still a lot to learn about dolphin communications to understand more about their behavior.
The study was published in the journal Bioacoustics.
Sign up for Chip Chick’s newsletter and get stories like this delivered to your inbox.
More About:Animals
Read This Next
