Coral bleaching threatens reefs at Mu Ko Surin National Park

The Department of National Parks, Wildlife and Plant Conservation is closely monitoring coral bleaching in Mu Ko Surin National Park in the Andaman Sea off Phang-nga province, particularly at Suthep Bay, where about 50% of the corals have bleached.

The department's director-general, Atthaphon Charoenchansa, said it is fortunate that the national park is closed until October 15, when it will reopen to tourists, adding that he hopes the closure will allow the corals to recover.

He warned, however, that if coral bleaching affects more than 40% of the corals in the park, the department may impose restrictions on scuba diving and other marine activities that could damage the reefs.

The number of visitors to the national park may also be limited, he added.

Atthaphon said the bleaching is believed to have been caused by unusually warm seawater. More than 160 hectares of coral reefs have been affected, with staghorn coral accounting for about 50% of the damaged coral.

Meanwhile, the park's chief, Arthit Khayankit, said sea temperatures now average 31°C, higher than during the same period last year.

The latest survey, conducted on June 26, found varying degrees of coral bleaching across the park, with about 50% of corals bleached at Suthep Bay, 30% at Pakkard Bay, and 10% at Mae Yai Bay, Tao Bay and Chong Kard.

He said park officials surveyed the reefs twice last month and again in the middle of this month to determine whether the bleaching had eased.

He added that a monitoring device has been installed to measure sea temperatures, while the park is also monitoring data from the US National Oceanic and Atmospheric Administration's (NOAA) Coral Reef Watch.

He said Mu Ko Surin National Park experienced its worst coral bleaching event in 2010, and it took about 13 years for the reefs to recover.