From Frog Fish to Whale Sharks
An extensive variety of marine animals abound in Thailand’s rich waters — a wonderland for divers. Here we have put together our top 20 list of highlights to introduce you to what you can discover when diving in Thailand.
The who’s who of marine creatures in Thailand
1. Whale Shark
The largest fish on the planet is not only at the top of our list, it is also an absolute highlight for most divers. No wonder then that we get daily enquiries about when and where to find and dive with whale sharks.
In Thailand there are spots where lucky divers can come across these magnificent creatures. But of course, there is always some good fortune that plays a hand in being at the right place at the right time, and to be looking in the right direction.
And if you do find a whale shark there is no need to worry; just like manta rays, although they are colossal creatures, they are perfectly harmless plankton eaters.
Best places:
Richelieu Rock, Koh Tachai, Hin Daeng & Hin Muang
Around the Phi Phi Islands, the King Cruiser Wreck, Shark Point and the Similans
Best times:
Best chances are from February to mid-May
Also occasionally around Phuket and Phi Phi in the low season and autumn.
2. Manta Ray
Another big fish on our list of Thailand diving highlights, and more frequently sighted than whale sharks are their cousins, the mantas.
Mantas, like whale sharks, are pelagic creatures living out in the open sea. They tend to return to specific cleaning stations where they congregate in groups, sometimes small and sometimes larger.
To dive with a manta ray is an unforgettable experience. And like whale sharks, they will at times come into shallower waters. So even beginners and snorkelers can be lucky enough to see one of these 6 metre large rays.
Best places:
In the south of Phuket, Racha Yai and Racha Noi, around the Similan Islands and Koh Tachai, one might see an individual animal.
On Hin Daeng & Hin Muang, and especially on Koh Bon, the chances are good to see several mantas at a dive.
Best times:
At the spots around Phuket, late in the year, around November / December. For the Similans, Koh Bon and Koh Tachai, January to April.
3. Leopard Shark
The most common species of shark in Thailand is the Leopard Shark. Also known as “lazy shark” as it spends most of its day resting on the sandy bottom, it will only tend to swim away if harassed by a group of divers.
In contrast to most other shark species, leopard sharks are not particularly shy, and will often allow respectful divers to approach, and might even circle around them curiously. They too are completely harmless.
Best places:
Leopard sharks are found in almost every part of Thailand, but have lessened in numbers in recent years. There are good opportunities around the Phi Phi Islands, especially Koh Bida Nok and Koh Bida Nai, at Koh Haa, Shark Point and Koh Tachai and the Similan Islands.
Best times:
You can see leopard sharks all year round, chances are much better in the off season when there are less divers around.
4. Black Tip Reef Shark
The black tip reef shark comes very close to how we picture the “classic” shark’s appearance. Reaching a size of up to 2m and with the distinctive black markings on their fin tips, they are easy to recognise.
Unlike leopard sharks, black tip reef sharks are almost always in motion. They tend to be very shy around divers and will quickly swim away. The best chances to observe them are during shallower dives. That’s why even snorkelers regularly meet up with this shark species.
Best places:
Phi Phi Islands, especially Koh Bida Nok / Nai and Phi Phi Leh
Best times:
All year round, though better chances in the low season when there are less divers and boats in the water.
5. Turtle
Turtles are another popular attraction in Thailand. Although they live in the sea, they come onto land to lay their eggs. In the Similans, in Thai Muang and in Mai Khao in the north of Phuket, to name a few places.
Turtles are found in many dive spots and are usually left in peace. They swim leisurely through the reef, chewing on sea grass here and there, leaving many traces. For us divers, they are of course, very easy to observe.
Best places:
Sightings are possible anywhere though more frequently at: Turtle Wall Phi Phi Island, Similan Islands, e.g. North Point in shallow water
On trips to the Similans, turtles are often seen in Donald Duck Bay, in search of bananas.
Best times:
Any time.
6. Barracuda
There are many varieties of Barracuda. The kinds we see in Thailand include: Great Barracuda, Yellowtail Barracuda, Crossbands Barracuda and Fosters Barracuda.
While the Great Barracuda is a loner patrolling the reefs and growing to longer than 2 metres, the other Barracuda species move in schools, are not as shy and will often circle divers, at times only a few centimetres away. Truly an incredible experience!
Best places:
In most spots, you might find isolated small schools of barracuda. Larger schools can often be found at Richelieu Rock, Koh Tachai, and Hin Daeng.
The smaller Fosters Barracudas congregate in large schools on the east coast of Racha Yai
Best times:
As Richelieu Rock, Koh Tachai, and Hin Daeng are closed from May to October, you can find them here only during the winter months.
At all other spots, all year round
7. Sea Snake
Even though snakes are not to everyone’s liking, an encounter with a sea serpent is certainly exciting. In Thailand there are two kinds of sea snake. The more common of these is the Yellow Lipped Sea Krait (cobra), unmistakable with its black and white stripes and easily found in many reefs.
The snake is highly venomous and can stay underwater for up to 20 minutes on one breath before having to resurface for air.
Divers can easily spot the snakes particularly in shallower waters on the hunt for small reef fish.
Best places:
Can be found on all shallow reefs, especially in the Similans, Phi Phi Islands, around Koh Haa, Anemone Reef, Shark Point and Koh Dok Mai
Best times:
Sea snakes can be sighted all year round
8. Clownfish
One of the smallest on our list, yet certainly one of the most popular: the Anemonefish, or Clownfish. Often also referred to as Nemo 
There are various types of Anemonefish, some of which are endemic to Thailand. Among them is the Orange clownfish, as the nemos are called. Other species include Clarks clownfish, which are darker in colour.
Best places:
Found on almost all reefs. Especially prevalent at Anemone Reef, Shark Point & Richelieu Rock
Best times:
All year
9. Ghost Pipefish
Ghost pipefish are mesmeric masters of camouflage. They are related to seahorses and needle fish, floating in and around soft corals in colours perfectly adapted to their environment.
It takes some practice and a good eye to find these animals, at a size of around 10 centimetres in length. But once you’ve spotted them, you can not take your eyes off these astonishing creatures.
Best places:
Can be found in most places. More frequently spotted at Koh Dok Mai, Richelieu Rock and the Similans
Best times:
Ghost pipefish are seasonal. November to January
10. Harlequin Shrimp
Harlequin Shrimp are the most beautiful of all shrimps.
Relatively rare and usually well hidden, they are among the highlights in the macro range. Harlequin Shrimp live in pairs and nourish themselves on starfish, which they turn on their backs and drag into their hiding place. There, the starfish are gradually dismembered and eaten.
Best places:
Koh Bida Nok (Phi Phi), Racha Yai, and especially Richelieu Rock
Best times:
All year round. On the diving safari to the Similans, usually better from January / February, as the guides will have already had a few weeks to track their current hiding places.
11. Seahorse
Rare is the diver who does not love the seahorse. Thankfully, there are many seahorses in Thailand and extremely beautiful ones at that. The most common seahorse species in Thailand is the Tiger Tail seahorse. Bright yellow, it sits between soft corals waiting to be discovered.
Best places:
At Anemone Reef, Shark Point, Koh Dok Mai, as well as Phi Phi Island and Richelieu Rock
Best times:
All year
12. Cuttlefish, Octopus and Squid
Cuttlefish, octopuses and squid are quite a sight to see when you are diving. All three are easily found in Thailand if you know where to look.
Cuttlefish are frequently seen in pairs above sandy ground. On Richelieu Rock they can often be found in the pairing or oviposition. Octopuses prefer to hide in stony terrain with many hiding places, also in and around coral reefs.
Squid can be seen in the open water above the reefs. Best seen when looking up from below.
Best places:
Basically possible in all spots. Especially frequent at Racha Yai, Phi Phi Island, Koh Haa, Richelieu Rock
Best times:
All year
13. Pegasus Fish
Among the lesser known animals of the underwater world are Pegasus fish. Almost always occurring in pairs; once discovered, they are easily identified by their distinctive body shape.
These small, odd creatures live well hidden on sandy ground and are only recognisable with a very practiced eye. Because of their rarity, they are one of the highlights for macro fans.
Best places:
Mainly located on the east coast of Racha Yai in the sand.
Best times:
All year
14. Frog Fish
Frogfish are real camouflage artists, well hidden in the reef. They exist in all conceivable colours and in many forms, perfectly adapting to their environment.
Best places:
Pretty much at all spots, especially on: Koh Dok Mai, Anemone Reef, Richelieu Rock
Best times:
All year
15. Nudibranchs
Distinct snails in all their varied shapes and colours are very popular with divers. Thailand is home to a large variety of nudibranchs, including such beautiful specimens as Chromodoris, Pyjama nudibranchs and Spanish Dancers.
By the way, we weren’t the ones who came up with these names.
Best places:
Can be found everywhere, especially on the King Cruiser wreck, Koh Dok Mai, Elephant Head Rock at the Similans
Best times:
All year
16. Cowrie Mollusc
Cowries are simply beautiful. They are actually snails who carry their own housing.
At Thailand’s dive sites, you will find various species of cowrie, including the big Tiger cowrie, Eggshell cowrie and tiny Tigers Eye and other soft coral cowrie, which are very well hidden on the corals.
Best places:
The Similans, Koh Bon west coast and, of course, Richelieu Rock. But can also be found at other spots occasionally.
Best times:
All year. But for Similans etc only in high season
17. Moray Eels
Though they might look terrifying, morays are actually rather harmless, unless they are fed or provoked. Moray eels present in various sizes and many patterns.
In Thailand, the most common are the small White-Eyed morays (also known as Greyface) as well as the Large moray eel. But also Laced morays, Ghost morays and Zebra morays are regularly seen.
Best places:
Moray eels can be found everywhere in Thailand. A great variety live for example the Boonsung Wreck at Khao Lak.
Ghost morays around the west coast of the Similans, for example West of Sweden, Christmas Point
Best times:
All year
18. Cleaner Shrimp
Cleaner shrimp are the second shrimp species on this list. Even though there are many other interesting and more beautiful shrimp and crabs in Thailand’s waters, Cleaner shrimp are something special.
They are known to voluntarily go inside the wide open mouths of fish and moray eels, and calmly pick away at the leftovers inside. It is a win-win situation for both the big fish and the little shrimp.
They have also been known to swim into the mouths of divers, if invited.
Try it out!
Best places:
At most dive sites. Particularly good chance on Anemone reef, Koh Dok Mai, Richelieu Rock
Best times:
All year
19. Scorpionfish
Members in the Scorpionfish family include dragonheads, firefish, stonefish and also the popular lionfish.
Species commonly found in Thailand include the “normal” dragon head and the so-called Bearded dragon head. There are also the Humpback dragon head, the Demon Stinger and the Indian Walkman. The latter two are mainly found on sandy ground while the Hump-backed dragonhead prefers a rocky bottom.
Best places:
Stonefish often found at Racha Yai, dragonheads at all places especially at the King Cruiser wreck. Demon Stinger and Walkman are quite rare, but they are everywhere where there are sandy areas, such as Racha Yai, Koh Bida Nai, Boonsung Wreck.
Best times:
All year
20. Many colourful fish
Last but Not least:
Although this list includes some of the largest, smallest, rarest and most unusual animals that divers can find in Thailand, they are not all that await you.
Thailand has an incredible diversity of species underwater. Fish and coral in all colours and shapes. The smallest shrimp, snails and crabs. Huge schools of snapper and fusiliers. Mackerel & Tuna on the hunt.
There are bat fish, doctor fish, parrot fish, sweetlips…
It’s not necessarily just the highlights that make diving special. It is also the variety of experiences and discoveries as well as just taking the time to observe and to enjoy. This is what makes a dive memorable. And when a particularly large, small or rare creature is sighted, it’s just the icing on the cake.
Would you like to dive with us and discover diving highlights of the Andaman Sea? Then write to us for further information for your next diving holiday in Thailand!