National park officials are sending boatloads of fresh water twice a week to a group of long-tailed macaques indigenous to Ko Rum Island,300 kilometres south of Bangkok.
"This year there has been no rainfall on the island," said Rungroj Assawakuntharin, head of Khao Sam Roi Yot National Park.
"We've had to ferry fresh water onto the island for the macaques which we deposit in a well."
The macaques rely on rainfall as the island has no ground water.
Their diet includes fruits and oysters, which they pry open with stones.
- DPA