Koh Tao · Marine Life

Species spotlights, seasonal sightings and the reef characters worth knowing by name.

22 stories

A colourful coral reef off Koh Tao teeming with tropical fish in clear blue waterMarine Life

Exploring Koh Tao's Underwater Wonders: A Marine Life Guide

From barracuda and trevally to lionfish, cuttlefish, pufferfish, boxfish, moray eels, batfish and sea kraits — a species-by-species guide to the marine life you can meet on Koh Tao's reefs.

20 May 2025 · Bryan Roseman
A scribbled filefish with its pale body covered in irregular blue lines and spots, hovering over a coral reef at Koh TaoMarine Life

Scribbled Filefish Koh Tao

The enigmatic scribbled filefish of Koh Tao — how to identify these living artworks, how they behave, where to find them on the island's dive sites, and the conservation challenges they face.

19 May 2025 · Bryan Roseman
A blacktip reef shark with its distinctive black-tipped dorsal fin cruising over a shallow reef in clear water off Koh TaoMarine Life

Blacktip Reef Sharks in Koh Tao

Everything about Koh Tao's blacktip reef sharks — how to identify them, how they behave and hunt, the bays where you can reliably see them, the best time of day, and how to watch them responsibly.

17 May 2025 · Bryan Roseman
A school of silver trevally swimming in a tight formation in blue water off Koh TaoMarine Life

Trevally Koh Tao: The Magnificent Silver Hunters Guide

Bluefin, Bigeye, Golden and Gold-spotted trevally — how to tell Koh Tao's four trevally species apart, where and when to see them, how they hunt and school, and how to observe them responsibly.

17 May 2025 · Bryan Roseman
A white-eyed moray eel with its pale eyes and speckled body peering out of a crevice in a Koh Tao reefMarine Life

The Enigmatic White-Eyed Moray Eels of Koh Tao: Guardians of the Reef

How to identify the white-eyed moray, how it hunts and breathes, where to find it on Koh Tao's dive sites, and why this misunderstood predator matters for reef health.

15 May 2025 · Bryan Roseman
A bigfin reef squid hovering in dark water at night off Koh Tao, its translucent body glowing with shifting coloursMarine Life

Squid Koh Tao: The Complete Guide to Bigfin Reef Squid Encounters

Everything about the bigfin reef squid of Koh Tao — how they hunt, communicate and change colour, the best dive sites and times to find them on night dives, and how to observe them without causing alarm.

15 May 2025 · Bryan Roseman
A longfin batfish with its diamond-shaped silver body and long fins hovering in blue water off Koh TaoMarine Life

Batfish Koh Tao: Complete Guide to Longfin Batfish Encounters

How to identify longfin batfish (Platax teira), where to find them around Koh Tao, how they behave around divers, and what threatens them — with a site-by-site guide and a short knowledge quiz.

13 May 2025 · Bryan Roseman
A spotted porcupinefish hovering over hard coral on a Koh Tao reef, with the caption "Pufferfish Koh Tao"Marine Life

Pufferfish Koh Tao: The Charming Underwater Personalities You'll Meet While Diving

Meet the three pufferfish species you can see diving Koh Tao — the Giant Puffer, the Porcupinefish (including Steve, the Junkyard's celebrity) and the Seal-faced Puffer — plus where to find them and how to interact responsibly.

13 May 2025 · Bryan Roseman
A red lionfish hovering over the reef off Koh Tao, its banded fan-like pectoral fins spread wideMarine Life

Lionfish Koh Tao: Complete Guide to Spotting These Magnificent Predators

How to identify the Red Lionfish, where it shelters around Koh Tao, when it hunts, how to stay safe around its venomous spines and how to photograph it respectfully.

12 May 2025 · Bryan Roseman
A Bearded Scorpionfish resting motionless on a rocky reef in Koh Tao, its mottled red-brown body blending into the substrateMarine Life

The Elusive Bearded Scorpionfish of Koh Tao: Masters of Camouflage

How to identify, spot and safely observe the venomous, perfectly camouflaged Bearded Scorpionfish — plus the Koh Tao dive sites where you are most likely to find one.

11 May 2025 · Bryan Roseman
A silver barracuda hovering in blue water off Koh Tao, its long torpedo-shaped body and prominent jaw clearly visibleMarine Life

The 3 Magnificent Barracuda Species of Koh Tao: Silver Predators of Thailand's Waters

Koh Tao hosts three barracuda species — the Great, Chevron and Pickhandle — each with its own look, behaviour and favourite dive sites. Learn to tell them apart, where to find them and how to position yourself safely around a barracuda tornado.

10 May 2025 · Bryan Roseman
A banded sea krait with black and silvery-blue bands swimming over a coral reef in Koh TaoMarine Life

Banded Sea Krait Koh Tao: Complete Guide to Spotting These Marine Snakes

Where and when to spot banded sea kraits around Koh Tao, how to identify them, how to observe them safely, and why these venomous but placid sea snakes matter for the reef.

9 May 2025 · Bryan Roseman
A bright yellow, cube-shaped boxfish with black spots hovering over a coral reef in Koh TaoMarine Life

Yellow Boxfish Koh Tao: Complete Guide to Finding These Unique Marine Creatures

Where to find yellow boxfish at Koh Tao dive sites like White Rock, Twins and Japanese Gardens, how they behave, what they eat and how to observe and photograph them responsibly.

7 May 2025 · Bryan Roseman
A translucent jellyfish drifting through blue water off Koh Tao, its tentacles trailing behind itMarine Life

Jellyfish Koh Tao

Which jellyfish live around Koh Tao, when you're most likely to see them, which ones actually sting, what to do if you're stung — and how the island compares with Koh Samui and Koh Phangan.

6 May 2025 · Bryan Roseman
A cuttlefish hovering above the reef in Koh Tao, its skin showing a mottled brown-and-white camouflage patternMarine Life

Cuttlefish Koh Tao: Complete Guide to Diving with These Amazing Cephalopods

Where and when to find cuttlefish around Koh Tao, how their colour-changing camouflage works, what their courtship and hunting look like, and how to observe them without causing stress.

6 May 2025 · Bryan Roseman
A blue-spotted ribbontail ray resting on the sandy seabed off Koh Tao, its bright blue spots standing out against the yellow-brown bodyMarine Life

Stingrays Koh Tao: Your Complete Guide to Three Amazing Species

Blue-spotted ribbontail rays, Jenkins' whip rays and the rare eagle ray — how to identify each species, where and when to find them around Koh Tao, and how to watch them responsibly.

4 May 2025 · Bryan Roseman
A titan triggerfish with its yellow, black and white patterning swimming over a reef at Koh TaoMarine Life

Triggerfish Koh Tao

The complete guide to diving with Koh Tao's triggerfish — the titan and yellow-margin species, where to find them (White Rock, Green Rock and the famous Trigger Pit), their territorial behaviour and how to stay safe.

4 May 2025 · Bryan Roseman
A whale shark swimming past divers in the blue water off Koh TaoMarine Life

Whale Sharks Koh Tao

When and where to see whale sharks around Koh Tao, how to dive and snorkel with them safely and respectfully, and how you can help protect the ocean's gentle giants.

3 May 2025 · Bryan Roseman
A diver hovering carefully above a healthy coral reef in Koh Tao, surrounded by small reef fishMarine Life

Marine Conservation in Koh Tao: A Complete Guide to Ocean Protection

The state of marine conservation in Koh Tao — the island's biodiversity, the threats its reefs face, the artificial reef, coral nursery and clean-up programmes protecting them, and how visitors can help.

30 April 2025 · Bryan Roseman
A hawksbill sea turtle swimming over a coral reef in clear blue water off Koh TaoMarine Life

Why Sea Turtles Are Important For A Healthy Ocean

Sea turtles are keystone species — they control jellyfish, keep seagrass beds and coral reefs healthy and signal the state of the ocean. Here is why they matter, what threatens them and how you can help.

29 April 2025 · Bryan Roseman
A diver hovering over a colourful coral reef in Koh Tao surrounded by schooling reef fishMarine Life

Koh Tao Marine Life: Complete Guide to Underwater Wildlife & Diving Species

Whale sharks, blacktip reef sharks, blue-spotted rays, sea turtles and the coral reefs that hold it all together — the species of Koh Tao, where to find them and when.

18 April 2025 · Bryan Roseman
Bleached white branching coral on a Koh Tao reef, with the caption "What is coral bleaching and why does it happen?"Marine Life

What Is Coral Bleaching And Why Does It Happen?

How and why corals bleach — the coral-algae relationship, the temperature thresholds that break it, what happens to a reef afterwards, and what divers can do to help.

16 April 2025 · Bryan Roseman

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