In a world-first, scientists are attempting to measure the “happiness” of dolphins by monitoring the behaviour of the animals at a marine park near Paris.
The project aims to assess life in captivity from the perspective of animals by examining what dolphins look forward to doing the most.
Researchers found dolphins are most happy when interacting with a human they have had a bond with.
They say, "better human-animal bonds equals better welfare".
The study, published in the journal Applied Animal Behaviour Science, was part of a three-year project to measure dolphin welfare in a captive setting.
Lead researcher Dr Isabella Clegg designed the experiment and examined the dolphins’ posture to determine how the animals were feeling.
She tested dolphins during sessions with a trainer, when they had toys in the pool and when they were left to their own devices.
"We found a really interesting result - all dolphins look forward most to interacting with a familiar human," Dr Clegg said told BBC News.
The animals showed this anticipation by "spy hopping", the action of peering above the surface and looking in the direction that trainers usually approached from.
