There are dozens of photos and YouTube videos of grieflike behavior in dolphins: Some mothers have been seen carrying their dead infants in their mouths or on their backs for a week or longer, even as the body decomposes; a couple adult males have also been seen holding dead calves in their mouths.

Dolphins are highly social and intelligent mammals that exhibit behaviors many scientists interpret as signs of sadness or grief, particularly after the loss of a calf or pod mate. One of the most common signs is "epimeletic behavior," where an adult dolphin (usually the mother) will refuse to leave a deceased calf, often carrying it on its back or balanced on its rostrum for days, even after the body begins to decompose. In 2026, researchers have documented this "mourning" in at least seven different species of whales and dolphins. Additionally, captive dolphins have been observed becoming lethargic, losing their appetite, or sinking to the bottom of their tanks and remaining motionless after the death of a companion. They may also emit specific low-frequency vocalizations that differ from their usual social "clicks" and "whistles," suggesting a state of distress or emotional processing that closely mirrors the mammalian response to loss observed in humans and elephants.