Fungie has not been seen in six days – the longest he has ever gone without human contact.
A wide scale search took place at the weekend involving fishing boats and Mallow search and rescue to find the dolphin who has long stayed in the Dingle area.
The team used sonar technology to scan the sea bed and sent divers below to look for clues to no avail.
Jimmy Flannery from Dingle Sea Safari and Dingle Dolphin Tours said it was not looking good.
"The boatmen are exhausted, so we just live in hope. I won't be able to spot a pod of bottlenose dolphins again without looking to see if our beloved Fungie is in the middle of them."
Fungie, who is believed to be over 40 years old, has been living in Dingle Harbour for 37 years but has never gone missing for this long.
The solitary dolphin, which means he does not live with a pod, thrives on human contact.
The search for Fungie will continue over the coming days but bad weather is forecast which could hamper the operation.
