The Ministry of Natural Resources and Environment will blacklist tour guides who damage the environment from national marine parks.
Natural Resources and Environment Minister Dapong Rattanasuwan, said guides who jeopardise coral reefs and marine life will be placed on the National Parks, Wildlife and Plant Conservation Department's blacklist, barring them from re-entering national parks.
"We have no authority to withdraw their tourism licence, as it is not our job. But what we can do is ban them from entering national parks. We have been aware of misconduct by guide and tourists," he said.
The warning came after a video posted online showed a sea-walker tour guide handling marine life and feeding bread to fish off Koh Hey near Phuket.
The video on Facebook was made to promote a sea-walker tour company and drew fierce criticism. The company later apologised, took down the video and promised the incident would not be repeated.
Gen Dapong said guides should know the dos and don'ts of visiting marine sites, adding that the best practice would be to inform tourists thoroughly on how to avoid actions that could threaten the sensitive marine ecosystem.
Thanet Mannoi, director of the Marine and Coastal Resources Centre in Phuket, told the Phuket Wan website on Monday that the guide had been sacked and the video was taken last year.
Koh Hey, a popular diving and sea-walking area for tourists visiting Phuket, is not part of a national marine park.
But department director-general Chonlatit Suraswadi said the department will have the power to protect marine life and resources in anywhere after a law promoting management of marine and coastal resources comes into effect in June.
The law was published in the Royal Gazette March 20 and will come into force three months after. It gives authorities power to take action against those damaging coastal and marine resources. Violators can be jailed for one year, fined up to 100,000 baht, or both.
Sea-walker tours, which have divers use surface-supplied air, large helmets and weightbelts to walk on the ocean floor, are promoted in some popular beach resorts, including Pattaya.