The researchers listened in on Delle with an underwater microphone for 69 days, between December 8, 2022, and February 14, 2023. Though they initially weren’t expecting much, the researchers say they detected communicative sounds in 35 out of the 69 days.

A solo traveler off the coast of Denmark is apparently screaming into the void, revealing the importance of social interactions for dolphins.

A solitary dolphin in the Baltic Sea has been recorded talking to himself, leading researchers to wonder whether he's lonely and calling out for friends.

A solitary bottlenose dolphin in the Baltic Sea has grown so lonely and devoid of companions that it may have started “talking” to itself, a new study suggests. The male dolphin, named Delle by locals, has been spending time in the Svendborgsund channel in Denmark, far outside the usual range of the species.

Delle might possibly be the loneliest dolphin in the world, spending his time adrift from other members of his species and desperately chatting to himself to pass the time

"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”.