The body of the dugong, a female estimated to be 30 years old, was found on the beach at Baan Hua Laem on Koh Lanta Yai, Krabi, at 5pm, Dr Kongkiat.
Healthy dugongs can live up to 70 years of age.
The remains were taken to the PMBC at Cape Panwa, on Phuket’s east coast in the hope that marine biologists there can determine the cause of death.
The dugong measured about 2.7 metres in length and weighed about 70 kilograms, PMBC Chief Kongkiat as confirmed.
“We found no wounds or cuts on her body,” he added.
From the condition of the remains, PMBC experts believe the dugongs had died three to five days before it was found, Dr Kongkiat added.
The dead female was reported as the second dead dugong to wash ashore Koh Lanta Island in the past two months, and the fourth one to be found in Krabi this year.
On Nov 30, another dead dugong was found washed ashore, this time on Tha Khao Beach on Koh Yao Noi, located just east of Phuket.