From Phuket To Phang Nga Bay - Box Jellyfish Habitat?

 

With plenty of talk about box jellyfish, whether they exist or not, at the popular beaches of Phuket in Thailand, here's a little reminder. 

One way or another, they do.

The Andaman Sea with its environment affected by monsoon-driven seasonal currents, massive internal waves and tidal influences, can get rough.

Box jellyfish are fragile and seek shelter to breed, mainly in coastal mangrove areas, meaning they tend to proliferate in more protected habitats, and as the seasons dictate.

The western and southern coasts of Phuket between May and October are out of bounds for box jellyfish. However, calmer waters mean more opportunity to feed and breed though empirical evidence suggests they much prefer the refuge of the east coast.

Serious stings have occurred on the seaward west coasts of both Phuket and Koh Lanta.

Keep in mind that there are two types or orders of box jellyfish, scientifically known as Cubozoans.

The multi-tentacled Chirodropida - specifically the potentially-lethal Chironex species - with up to 60 tentacles, as well as the single-tentacled Carybdeida with only four tentacles.

Fatalities from the former are thankfully few at both locations while the latter, mainly in the form of the more sleek and robust yet extremely dangerous Morbakka, continues to pop up and deliver an excruciatingly painful whack.

Phuket's east coast, home of the Royal Phuket Marina and mangroves, calmly extends into Phang Nga Bay and the famous James Bond Island, Ko Khao Phing Kan.

Further south in the bay are the likes of Ao Nang and Krabi, while central just up from bigger Koh Yao Yai lies Koh Yao Noi.

Multi-tentacled box jellyfish are indeed present here.

The risk associated with these is enormous.

They are proven killers. In only minutes. Fast, efficient, deadly. 

Now, that's not to say you are likely to see one. In fact, it is highly unlikely. But perhaps somewhat like others sharing the sea such as certain sharks or whales or whatever, box jellyfish can appear when you least expect it.

Being aware gets you closer to being prepared, and of course there is plenty you can do as written about in this blog to give yourself the best chance in case of an emergency.

Prevention & Treatment Dos & Donts

In the meantime, these images of a Chironex species of multi-tentacled box jellyfish taken from Koh Yao Noi's picturesque Tha Khao beach pier in April 2026 confirm its presence.

At least in Phang Nga Bay.

Photo Credits: Facebook - Elisa Pursianinen, Travel To Thailand