The Similan Islands are a world-renowned scuba diving destination and for good reason. Situated in the Andaman Sea, north of Phuket, these nine uninhabited islands offer crystal clear waters, an abundance of hard and soft corals, and spectacular marine life.
Scuba divers of all levels can find something to enjoy here, from shallow reefs teeming with colourful reef fish to deep walls blanketed in purple gorgonian fans. If you're lucky, you might even spot a whale shark! Here are the top 10 marine life you can expect to see on a Deep Andaman liveaboard trip.
1. Whale Sharks
Whale sharks are the largest known fish species and can grow up to 12 metres in length. These gentle giants are filter feeders that consume plankton, small fish, and squid. Although they are often seen as solitary, they will sometimes gather in large groups called 'aggregations' which can number in the hundreds. The best time to see whale sharks around the Similan Islands is between October - January and March - April.
2. Manta Rays
Manta rays are easily recognised by their large triangular fins and wide mouths which they use to filter feed on zooplankton and small fishes. These beautiful creatures are often seen around cleaning stations where they wait for smaller fishes to pick parasites off their skin. You can find them all year round in the Similans but the best time to see them is between February and April.
3. Turtles
Five of the seven species of sea turtles can be found in Thai waters and four of them have been spotted around the Similan Islands National Park. Keep your eyes peeled for the green turtle, hawksbill turtle, loggerhead turtle, and leatherback turtle as you dive around the reefs. These gentle creatures are often seen grazing on seaweed or swimming gracefully through the water column. If you're lucky enough to encounter one while diving, please don't touch or chase after them as this can cause unnecessary stress.
4. Nudibranchs
Nudibranchs are a type of soft-bodied marine gastropod mollusc that come in all sorts of shapes and sizes. They are often brightly coloured and some have external structures that resemble feathers, horns, or frills. With over 3,000 species described so far, nudibranchs are one of the most diverse groups of marine animals in the world. The best time to see them is between November and April when they are most active.
5. Barrel Sponges
Barrel sponges are some of the largest sponges in the world with some species growing up to two metres tall! Although they look fragile, barrel sponges are actually quite tough and have been known to live for over 2,000 years! These ancient animals play an important role in coral reef ecosystems as they provide shelter for small fishes and act as a food source for turtles and nudibranchs. You can find barrel sponges all year round at most dive sites in Thailand but they are especially abundant around Koh Bon and Koh Tachai from March to May.
6. Seahorses
Seahorses can be found hiding amongst the seagrass beds near Koh Tachai. These elusive creatures are well camouflaged but divers who take their time searching will be rewarded with sightings of these unique animals. As seahorses are very delicate, please do not touch or attempt to move them if you find one. You can find seahorses all year round but they are most active from November to April.
7. Moray Eels
Moray eels are a type of snake-like fish that can grow up to four metres in length. They have large mouths with sharp teeth which they use to eat small fishes and crustaceans. Although they may look aggressive, moray eels are actually quite shy and will only attack if they feel threatened. You can find them hiding in holes and crevices at most dive sites around the Similan Islands but they are most active from October to April.
8. Lionfish
Lionfish are a type of venomous fish that are native to the Indo-Pacific region. They are easily recognised by their colourful stripes and long fins which they use to scare away predators. Lionfish are not aggressive towards humans but their venomous spines can cause extreme pain if you're unfortunate enough to get stung. You can find them at most dive sites around the Similan Islands but they are most active from November to April.
9. Giant clam
Giant clams are the largest type of clam in the world and can grow up to two metres in length. These beautiful creatures are often found in shallow water where they filter feed on phytoplankton. They are also an important food source for many animals including turtles, fishes, and nudibranchs. You can find giant clams all year round at most dive sites around the Similan Islands.
10. Sharks
People often fear sharks but they are quite shy and pose no threat to humans unless they feel threatened. There are many different species of sharks that can be found in the waters around the Similan Islands but the most common are the blacktip reef shark, whitetip reef shark, and leopard shark. You can find them at most dive sites but they are most active from November to April.
So there you have it, our top 10 marine life to see in the Similan Islands!
The Similan Islands offer scuba divers of all levels an opportunity to explore abundant marine life in crystal clear waters. From gentle giants like whale sharks to colourful nudibranchs, there's something for everyone to enjoy here.
We hope you have a fantastic time diving around these beautiful islands and remember to take care of our underwater friends!
So what are you waiting for? Book your Deep Andaman Queen liveaboard adventure today!