Fingal County Council has said what is believed to be a leatherback turtle was found after being washed up on Portmarnock Beach in Dublin yesterday.
In a statement, the Marine Institute confirmed the turtle appears to be a leatherback turtle, which has been recorded in Irish waters previously.
"Leatherback sea turtles have been recorded all around Ireland, in the Atlantic, as well as the Irish and Celtic Seas. However, this species is not seen very regularly."
The institute said that the species is primarily seen during summer months.
"Sightings of Leatherback sea turtles in Ireland have mostly been recorded during the summer months from July to September, as this is when jellyfish are most abundant in our waters.
"Leatherbacks are long-distance seasonal migrants to Irish waters, and migrate to temperate waters for feeding and then return to waters near to where they are from to find a mate and for nesting," the statement added.
Walkers on Portmarnock Beach had made the discovery yesterday when they came across the large turtle species on the sand.
Niamh Griffin, who walks in the area regularly, said that when she first saw the creature in the distance, close to Burrow Beach in Portmarnock, it looked like a pile of black tyres and was not moving.
"You couldn't miss it because it was so big, but we didn’t know what it was exactly but we knew it was a type of turtle.
"I’ve never seen anything like that before on an Irish beach," Ms Griffin added.
Fingal County Council said it has made contact with the National Parks and Wildlife Services.
The council advised that the Irish Whale and Dolphin Group took stranding bio data from the turtle and arrangements will be made for a burial.
Additional reporting Dyane Connor
