Mr Rajeshpal Singh Khalsa was with his family at East Coast Park yesterday morning when they saw what was initially thought to be a large boulder on the beach.
But when they got closer, he saw that the "boulder" had a fin.
It turned out to be a 1.8m-long dead dolphin.
Mr Singh, 30, who said there was no stench, called the National Parks Board (NParks).
The New Paper on Sunday understands that the carcass has since been retrieved and will be handed over to the Lee Kong Chian Natural History Museum, which is part of the National University of Singapore (NUS).
Mr N. Sivasothi, a biological sciences lecturer at NUS, says that the museum had previously dealt with washed up dolphin carcasses in 2005 and 2008.
In both incidents, the mammals had been washed up on Labrador beach in the west.
There had been another case of a washed up dolphin carcass on the ECP just earlier this week, he said. But in that instance, the flesh was mostly gone from the carcass.
"We will make arrangements to recover it for the museum, take tissue samples, preserve the bones for research and education purposes," he said.
He added: "Preserving the skeleton allows visitors to the museum and at our annual Festival of Biodiversity realise we have a regional marine heritage worth protecting."
He said the most commonly sighted dolphin species in our waters is the Indo-Pacific humpbacked dolphin, also known as the pink dolphin.
In our northern waters, sightings of the sea cow, or dugong, are more common. These are likely to be part of the population whose habitat is in Sungei Johor, Mr Sivasothi said.
He added that their carcasses have also washed up on our shores in areas including Changi beach, ECP and even Pulau Tekong. The last case, which was in Pulau Tekong, happened in 2006.
Members of the public who see such carcasses can call the Animal Concerns Research and Education Society (Acres) Wildlife Rescue Hotline on 9783-7782.
This article was first published on July 20, 2014.
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