From Thailand to Myanmar: An Exceptional Andaman Sea Adventure
The MV Smiling Seahorse set off once again for an exceptional cross-border adventure — a journey from Thailand’s Surin and Similan National Parks to Myanmar’s wild Mergui Archipelago. This week we welcomed our wonderful guests from Israel, excited to explore two countries, two ecosystems, and a whole spectrum of marine life.
After check-in and Thai immigration formalities, we boarded the boat and headed across the Pakchan River to Kawthaung for Burmese immigration. Passports stamped, gear prepped, smiles wide — our expedition began.
Day 2 — Mergui’s First Wonders
Our first dive at High Rock was the perfect warm-up. We drifted along the rocky outcrops and immediately met two tigertail seahorses hiding among the hard corals. Thornback boxfish hovered curiously near the walls while crocodile needlefish glided just under the surface. A busy peacock mantis shrimp scuttled across the sand, and Durban dancing shrimps flashed their white antennae from inside tiny crevices. Moray eels peeked out from the reef — fimbriated and white-eye morays sharing the same neighbourhood — and a cooperative group of four scribbled filefish swam past, changing colour as they fed. Schools of trumpetfish, lionfish, bearded scorpionfish, coral and peacock groupers, snappers, fusiliers, and a handful of blackfin barracudas filled the water column, with a white-tongue trevally circling us during the safety stop.
At Three Islets, the Submarine site gave us a lovely first encounter with a bamboo shark tucked into a rocky crack, and a turtle drifting lazily overhead. We found orange-spotted pipefish and the elegant nudibranch Chromodoris rufomarginata. Shark Cave was buzzing with life; the entire cave shimmered with sweepers, and outside the entrance clouds of fusiliers pulsed in the current. Sergeant majors were fiercely defending their eggs while wrasses, angelfish, butterflyfish, and triggerfish opportunistically picked at any moment of distraction. Wahoos streaked through the blue, accompanied by a great barracuda, golden trevallies, and even a giant bicolour parrotfish. Square continued the spectacle with more tigertail seahorses, a giant moray, and well-hidden bearded scorpionfish.
Our night dive around Square and Shark Cave was a treasure hunt of nocturnal critters. Five tigertail seahorses showed up, along with sponge spider crabs, decorated crabs, Godiva quadricolor nudibranchs, and sleepy pufferfish wedged among the corals. Soldierfish and cardinalfish hovered in the glow of our torches while hinge-beak shrimp and banded cleaner shrimp darted from rock to rock.
Day 3 — Twin Islands & Blackwater Magic
At North Twin Reef, we descended into crystal-clear blue water where sea snakes wove gracefully across the reef. Oriental sweetlips gathered in loose schools, and anemonefish bobbed in their host anemones. Giant morays, surgeonfish, and redtooth triggerfish patrolled the boulder fields. Seal-face pufferfish, boxfish, and a forest of staghorn, lettuce, and foliose corals created a vibrant underwater landscape.
South Twin Reef delivered even more action with partner shrimps and peacock mantis shrimps scurrying along the sandy patches. Juvenile triggerfish flicked between coral heads while gold-saddle rabbitfish fed in tight groups. Four dogtooth tunas shot past in formation. Blue dragon nudibranchs were scattered everywhere, and the reef was alive with lined and stripe-bristletooth surgeonfish. A Jenkins ray rested on the sand beside a blue-spotted stingray, while yellow-edge and giant morays watched from shaded holes. An octopus shifted colours as we approached, and juvenile oriental sweetlips wiggled in their rhythmic dance. We ended the dive drifting over beautiful table corals and elegant funnel corals.
That evening’s blackwater dive was a mesmerising drift over the deep. Squid zipped through our lights while baby scribbled filefish floated in their larval form. A banded sea snake surprised us with a rare mid-water visit. Transparent larval shrimps, lobsters, crabs, and mantis shrimps hovered like tiny spacecraft, and pteropods and flying-gurnard larvae pulsed through the darkness.
Day 4 — Sea Fan Forest & Western Rocky
Our two dives at Sea Fan Forest were spectacular. We explored towering forests of gorgonians where another tigertail seahorse clung to the branches. Yellow-lined and neon fusiliers filled the water column, pursued by rainbow runners weaving through the openings. We found several octopus, stonefish, and devil scorpionfish, along with nudibranchs such as Chromodoris, Risbecia annulata, and Geometrica. Zebra morays slithered over the rocks, yellow trumpetfish hovered motionlessly beside sea fans, and peacock mantis shrimps guarded their burrows. Juvenile boxfish, needlefish, and a perfectly-patterned young emperor angelfish added splashes of colour. A curious cuttlefish rounded off the dive with a gentle display of shifting patterns.
At Western Rocky, we entered the famous cave with octopus and cuttlefish patrolling the entrance. Coral-banded shrimp and red reef crabs clung to the walls, and we spotted a delicate wentletrap snail and a striking Maldivian sponge snail on the sandy floor. Blue dragon nudibranchs added flashes of purple and white as we continued along the reef, passing bannerfish, goatfish, snappers, and butterflyfish enjoying the current.
Our sunset dive around the Western Rocky islets unfolded beautifully as clouds of fusiliers, sergeant majors, and damsels swirled around us. Harlequin shrimps crept delicately over the rocks, and more Maldivian sponge snails dotted the reef. White-tongue trevallies chased schools of baitfish, accompanied by scribbled filefish, pyjama surgeonfish, rainbow runners, golden trevallies, and a pack of blacktail barracudas. At one point, two giant morays squeezed together inside the same hole, seemingly unbothered by each other’s presence.
Day 5 — Mantas, Currents & Forest Walls
Back at Dendro’s Peak, we descended along a slope draped in purple soft corals. Yellow-lined, neon, and yellowback fusiliers streamed past in glittering clouds while rainbow runners and mackerel darted along the edges. Bannerfish hovered near coral heads, trevallies patrolled the shallows, and a banded sea snake explored the cracks. Zebra morays peeked out from the reef, and coral groupers hunted through the bommies. A large turtle drifted peacefully overhead — and then the highlight of the day arrived as two magnificent manta rays swept gracefully above us, circling repeatedly.
The afternoon dives at Sea Fan Forest were equally memorable. Fusiliers filled every corner of the reef, and another tigertail seahorse clung to a sea fan. A pharaoh cuttlefish hovered confidently before drifting away into the blue. Pickhandle barracudas and golden trevallies patrolled the sandy patches while batfish, moorish idols, and titan triggerfish appeared throughout the site. A large tiger cowrie, several anthias, wrasses, butterflyfish, and damsels added detail to the coral scene. More octopus and a well-camouflaged stonefish ended the day.
That night’s blackwater dive was exceptionally special, featuring a female paper nautilus drifting like a delicate origami shell. Larval wrasses and tiny fish sheltering inside jellyfish floated through the dark, and we found many larval triggerfish and fish living inside salps — a perfect finale to the drifting night.
Day 6 — Into Thailand: Surin & Richelieu Rock
We re-entered Thailand in the early hours and cruised south toward Richelieu Rock, where perfect conditions awaited us.
What Makes Richelieu Rock Famous?
- A horseshoe-shaped pinnacle covered in purple and pink soft corals
- Massive schools of trevallies, barracudas, and snappers
- Incredible macro life: ghost pipefish, harlequin shrimps, tiger-egg cowries
- Historically known for whale shark sightings
- Named after Admiral Andreas du Plessis de Richelieu, a Danish officer who served as Commander-in-Chief of the Royal Siamese Navy — not the French cardinal, despite the popular legend
Our first dive at Richelieu Rock was enchanting. Dense schools of glassfish wrapped the entire reef in a shimmering veil. Longnose emperors worked in tight groups, flashing brilliant colours as they hunted, while giant trevallies, bluefins, white-tongue trevallies, and bigeyes patrolled the edges. Batfish hovered calmly around the cleaning stations, and titan triggerfish bulldozed their way along the bottom. Octopus displayed quick colour changes, and huge potato groupers watched us from between the cracks. White-eye, zebra, and yellow-edge moray eels peeked from the crevices, and tiny tiger-egg cowries clung to sea fans. Nudibranchs including Chromodoris and Flabellina added delicate splashes of colour while bannerfish, wrasses, dartfish, anthias, and butterflyfish decorated every corner of the reef.
Our night dive at Surin South (Ao Pakkard) offered a different perspective. Giant red crabs prowled the sandy areas, Durban dancing shrimps and marble shrimps flickered under our torches, and boxer-banded shrimps waved their oversized claws. Parrotfish, surgeonfish, and pufferfish were already tucked into their nighttime hideouts, while barracudas sliced through the dark hunting yellowback fusiliers.
Day 7 — Richelieu, Similans & Koh Tachai
We returned to Richelieu Rock for two more morning dives filled with action. Longnose emperors swam in the shallows where cleaners worked tirelessly around their open mouths. Giant trevallies and chevron barracudas surged through the schools of glassfish. We found beautiful harlequin shrimps, cleaner and orange-spotted pipefish, and several potato groupers cruising the bommies. Boxfish, angelfish, needlefish, cobia, black snapper, and African pompano all made appearances. A large marble ray glided past us to complete the scene.
Similan National Park Highlights
- Famous for giant granite boulders and white-sand beaches
- Excellent visibility and vivid blue water
- Frequent encounters with manta rays, whale sharks, and giant trevallies
- Beautiful coral gardens with sea fans, hard corals, and soft coral patches
Our third dive at Koh Tachai brought us into the energetic mix this site is known for. Bluefin trevallies and chevron barracudas hunted in packs while giant trevallies and dogtooth tunas patrolled the deeper zones. Marble groupers rested on the bommies while longfin bannerfish, unicorn surgeonfish, angelfish, and massive swarms of fusiliers filled the reef. Lobsters and snappers hid among the corals, and batfish drifted by in lazy groups.
At Koh Bon, we explored the ridge and bay where hard corals glowed beautifully in the afternoon light. A baby blacktip shark cruised the shallows while an octopus hid in a coral crack. Maldivian sponge snails dotted the reef. The dive ended with colourful scenes full of wrasses, goatfish, butterflyfish, damsels, and scorpionfish, with the occasional wahoo and giant moray cruising through the dusk.
Day 8 — Racha Noi to Finish
Our last day took us south to Racha Noi, where Banana Bay offered a relaxed sandy slope with scattered bommies teeming with damsels, redtooth triggerfish, Meyer’s butterflyfish, fiveline and checkered snappers, longbarbel goatfish, squirrelfish, and gold-saddle rabbitfish. A banded sea snake glided along the reef, and a mantis shrimp, guarded closely by its pair of squat shrimps, kept watch from its burrow.
At Manta Reef, we found Glossodoris cincta, a snowflake moray, and several seal-face pufferfish drifting over the sandy bottom. Garden eels swayed in the light current as blue-spotted rays glided past. Butterflyfish, damsels, and a bearded scorpionfish rounded out the dive while yellowback fusiliers danced above in glittering swirls.
A Perfect Journey Across Two Countries
From Myanmar’s caves and giant sea fans to Thailand’s iconic reefs, this trip delivered unforgettable moments: manta rays, seahorses, endless fusiliers, dramatic landscapes, and amazing energy from our guests.
Thank you to our wonderful divers from Israel for sharing this week with us and their wonderful photos to illustrate this blogpost!
See you soon for another adventure with the MV Smiling Seahorse! 🐟💙
One Response
Thank you for a wonderful journey ❤️