Researchers building a dictionary of dolphin whistles found the 240 sea mammals in Cardigan Bay have their own distinct Welsh dialect.
The Dais' whistle will form part of a dictionary of nearly 2,000 dolphin sounds from around the British Isles.
It follows revelations that birds chirp and cows moo in regional accents in different parts of Britain.
The study was made by marine scientist Ronan Hickey, of the University of Wales in Bangor, and experts from the Shannon Dolphin Foundation in Ireland.
They digitised and analysed 1,882 whistles from 120 Irish Sea dolphins to find the Welsh dolphins had their own accent.
Project leader Dr Simon Berrow said: "We're trying to associate whistle types with different forms of behaviour - like foraging, resting, socialising and communicating with their young.
"One was distinctive and exclusive to the dolphins of Cardigan Bay.
"We're really building up a dictionary of a whole range of sounds. There are whistles, clicks, barks, groans and a gunshot sound which they might use to stun their prey."
The Welsh dolphins are a major attraction for tourists on boat trips from New Quay and Aberaeron and from vantage points on the coastline.
More than 25,000 holidaymakers take sightseeing tours on boats every year to watch the antics of the dolphins.
Cardigan Marine Wildlife Centre manager Steve Hartley said: "It makes sense that different groups of dolphins separated by large distances have different accents.
"It's nice to know they have their own Welsh accent accent.
"Dolphins are very important to our tourist industry and I'm sure the fact that they whistle in Welsh will be an added attraction."Reuse content