Thousands of people have watched the online video of the moment a woman was struck repeatedly by Dusty the Dolphin in Doolin.
She had to be pulled from the water and was taken to hospital by ambulance, having suffered a compressed vertebrae, broken rib and damage to her lung.
Warning signs have been erected by the local council and the Irish Whale and Dolphin Group, advising members of the public not to try to swim with Dusty.
The action was taken after a number of reports of aggressive behaviour towards people - although it is still unclear if the dolphin was only being playful.
Respect her as a wild dolphin and do not grab, lunge or chase after her.
Irish Whale and Dolphin Group
At least five other people have been hurt, including one woman who was taken to hospital after being rammed in the stomach and another who was airlifted to hospital in Germany."If this continues, it may lead to a fatality and there will be strong pressure to remove or destroy the dolphin," a statement from the Irish Whale and Dolphin Group said.
"If you really are concerned about Dusty, you will not swim with her - or at least if you do, you should show her the respect a wild dolphin is entitled to."
Dusty has been around since 2000 and experts are urging people to respect that she is a wild animal.
"It is IWDG policy to discourage people swimming with whales and dolphins," the group said.
"The risk is not only to humans, but also to the dolphin - as habituation to humans increases risk of injury or death to the dolphin."
The group recognises that many people have enjoyed their experiences swimming with Dusty, but is concerned that some do not recognise the signals sent out when the dolphin is not happy.
Back in 2004, a tourist reported that she had been attacked by the dolphin and that she had feared she would drown as she was pushed out to sea.