A whale and dolphin conservation group, Equinac, said the incident occurred Saturday on the tourist beach of Mojacar, in the southeast of the country.
Bathers played with the dolphin in the shallows, inadvertently blocking her breathing hole and pulling her from the water for pictures, probably causing stress that proved fatal, it said.
The baby may have turned up on the beach because it was separated from its mother — in which case, it could not have survived — or because it was sick, Equinac suggested.
Twitter users responded with outrage.
“If you go to the beach, leave your stupidity at home,” said one.
“Did you take selfies after it died?” asked another.
A Facebook posting by an animal rights party, Pacma, which blamed “harassment by bathers” for the mammal’s death, was “liked” more than 4,800 times.
