Sea Snake
Scientific name Laticauda colubrina
The Black & White Banded Sea Snake — more accurately known as the Yellow-Lipped Sea Krait — is one of the most striking and occasionally encountered reptiles around Koh Tao. With bold black and white bands wrapping around its body and a distinctive yellow snout, it’s unmistakable underwater.
Growing up to around 1.5 metres in length, sea kraits are perfectly adapted to life in the ocean, with a flattened paddle-like tail for swimming. Unlike true sea snakes, however, they are amphibious — meaning they still come ashore to rest, digest food and lay eggs.
Around Koh Tao, sightings are uncommon but memorable. They’re typically seen weaving gracefully through coral crevices or along rocky reef slopes, hunting for prey. Their movement is smooth and deliberate, and they often appear calm and completely uninterested in divers.
Black & White Banded Sea Snakes are highly venomous — but extremely docile. They use their venom exclusively for hunting and have no interest in defending territory. Bites to divers are extraordinarily rare and typically only occur if handled or provoked.
They play an important ecological role as specialised predators, feeding primarily on eels hiding within reef cracks. By controlling eel populations, they help maintain balance within the reef ecosystem.
A sea krait sighting is one of those rare, slightly surreal moments on a dive — elegant, ancient and quietly powerful.
Find Sea Snake at...
Divemaster's tip
If you’re lucky enough to see one, give it space and simply observe. Sea kraits are focused hunters and rarely react to divers unless approached too closely.
Look along rocky crevices and reef walls between 5–20 metres. Their bold banding makes them stand out clearly against coral backgrounds.
What do they eat?
Black & White Banded Sea Snakes feed mainly on eels, particularly moray species hiding inside reef cracks. They use potent venom to immobilise prey before swallowing it whole.
They must surface regularly to breathe, as they are reptiles, but can remain underwater for extended periods while hunting around Koh Tao’s reefs.
