The high number of tourists on the islands, especially visitors from mainland China, resulted from the extended holiday celebrating the Visakha Puja Festival and tourists rescheduling their trips to accommodate the closure.

Parks head Ruamsilpa Manajongprasert said on Sunday that the Department of National Parks, Wildlife and Plant Conservation had announced the Andaman Sea islands in Mu Koh Similan National Park, Mu Koh Surin National Park, Mu Koh Lanta National Park’s Koh Rok and Koh Ha in Krabi, Tarutao National Park’s Adang Ravi and Lipe islands in Satun, and Hat Chao Mai National Park’s Hin Moung-Daeng Island in Trang would be closed to visitors from Tuesday to October 15.

The closure is an annual measure to prevent tourists from being harmed during the monsoon season and to allow nature to restore itself.

Ruamsin said he would send park officials to monitor the islands to prevent unauthorised visitors during the closure period. Officials will patrol in boats regularly to check on the parks to prevent illegal fishing, he added.

Koh Bon, located between Koh Lanta and Koh Tachai, was a particular concern as fishermen have often been caught fishing in the area during the monsoon season, resulting in damage and the deterioration of the natural resources, he said.

The department can be called at 025610777 and 025796666 for more details about the closures.