Beach red flags fly as Ko Lanta closes sites over Portuguese man o’ war

THURSDAY, JUNE 11, 2026
Beach red flags fly as Ko Lanta closes sites over Portuguese man o’ war

Mu Ko Lanta National Park has shut Laem Tanot, Ko Haa and Ko Ngai after large numbers of Portuguese man o’ war were found washed ashore.

  • Mu Ko Lanta National Park has temporarily closed three tourist sites due to large numbers of Portuguese man o’ war washing ashore.
  • The closure, which began on Thursday, affects Laem Tanot, Ko Haa, and Ko Ngai to ensure visitor safety.
  • The Portuguese man o’ war is highly venomous, with tentacles that can cause severe pain and injury even after the creature is dead.
  • In addition to the closures, officials have raised red flags to warn tourists against swimming in affected areas.

Mu Ko Lanta National Park in Krabi province has issued an urgent announcement ordering the temporary closure of three tourist sites from Thursday (June 11, 2026) after officials found large numbers of Portuguese man o’ war washed ashore on beaches, posing a risk to people swimming or carrying out activities along the shoreline.

Three Mu Ko Lanta sites closed as Portuguese man o’ war monitored

Officials had earlier put up red flags warning tourists not to swim in several areas after the species was found washed ashore repeatedly.

Beach red flags fly as Ko Lanta closes sites over Portuguese man o’ war

For maximum safety, the park decided to close three main tourist sites:

  • Laem Tanot (the park headquarters area)
  • Ko Haa
  • Ko Ngai

The park will closely assess the situation and will reopen the areas to visitors once conditions return to normal.

How dangerous is the Portuguese man o’ war

The Portuguese man o’ war is considered highly venomous, particularly its tentacles, which can release venom at all times, even after it has died or been washed ashore.

Contact with the venom can cause severe burning pain, burn-like red rashes on the skin, breathing difficulty and, in severe cases, loss of consciousness.

Beach red flags fly as Ko Lanta closes sites over Portuguese man o’ war

Safety advice and basic first aid

Mu Ko Lanta National Park recommended the following safety measures:

  • Do not touch under any circumstances: Do not pick up any Portuguese man o’ war or remains found on the beach to play with or photograph.
  • Notify officials: If this species is found washed ashore, notify park officials immediately.
  • Protect yourself: Tourists should wear shoes while walking on beaches and avoid swimming in areas where officials have issued warnings.

First aid if affected by venom

  1. Leave the water immediately.
  2. Avoid scratching or rubbing the affected area under any circumstances.
  3. Closely monitor the injured person’s condition.
  4. Take the person to a medical facility or notify park officials for immediate help.

Beach red flags fly as Ko Lanta closes sites over Portuguese man o’ war Beach red flags fly as Ko Lanta closes sites over Portuguese man o’ war