The search for beloved dolphin Fungie was suspended yesterday due to poor weather conditions off the Kerry coast.
Boatmen scoured Dingle Bay in west Kerry for three days without a single trace of the Common Bottlenose dolphin being found.
Fungie was last spotted by a fisherman on Thursday morning - but there was concern after he inexplicably vanished last Wednesday.
Follow-up searches by a flotilla of leisure craft and fishing boats failed to obtain a single sighting of Fungie between Friday and Sunday.
On Sunday, divers were even deployed in a bid to inspect the caves and inlets where he traditionally swam and fed.
But no trace of Fungie was spotted amid mounting fears he may have fallen ill or even died.
Boatmen stressed it was highly unusual for Fungie to leave his normal patrol waters for more than a few hours.
In all his years as a tourism icon in Dingle, Fungie never left the bay for more than half a day.
Fungie arrived in Dingle in 1983 and is believed to be around 40 years old. Males generally live for between eight and 17 years.
However, in exceptional circumstances, dolphins have been known to survive for almost 70 years.
Dingle Sea Safari confirmed that the search was being called off as poor weather swept over the south west.
Fishermen and boatmen have vowed to keep a lookout for any trace of Fungie.
"Wherever you are my friend I hope you are safe and happy and thank you for all the years of joy you have brought to so many people," Dingle Sea Safari added.
Coastal walkers have also been asked to keep a look-out.
Marine experts said that if a dolphin dies in the open sea, it is very unusual for it to then be washed ashore.
Boat operator Jimmy Flannery said everyone was "hoping against hope" that Fungie would turn up safe and well.
"But it is totally out of the ordinary for Fungie. It is not like him at all.
"The longest in my 33 years for him to disappear is just for a few hours.
"He has never been gone this long before. These are worrying times."
Last May, Jimmy took his boat out at the height of the Covid-19 lockdown just to keep Fungie company in case he was lonely at the absence of his normal audience of admirers.
Also known as the Dingle Dolphin, Fungie is a male Common Bottlenose Dolphin.
First spotted off Dingle in the summer of 1983, Fungie became a tourist sensation with his antics near leisure craft and his clear love of being watched.
Marine biologists were astounded at the manner in which he seemed to actively seek out human contact.
The lone male dolphin preferred to operate on his own - but loved to interact with boats, fishermen, sightseers, divers, surfers and kayakers.
Fungie has also contributed to marine science -with his appetite for garfish off the Dingle being the first recorded instance of dolphins eating the sleek fish also known as the Sea Needle.
For the past 37 years, Fungie has helped underpin a major marine tourism business in west Kerry.