Some expeditions meet expectations. Others quietly reset them...
Our latest journey into Myanmar’s far north delivered exactly what these waters are famous for: a beautiful balance between pelagic encounters and intricate macro life. From oceanic mantas and nurse sharks to flamboyant nudibranchs and rare frogfish, this voyage reminded us why the Mergui Archipelago and the Burma Banks remain some of the most rewarding dive destinations in Southeast Asia.

​With immigration formalities completed in both Thailand and Kawthung, we welcomed our Dive Buddy guests from Israel aboard the Smiling Seahorse and pointed the bow north. Gradually, the busy coastline gave way to scattered islands draped in dense jungle, hinting at the wild underwater world awaiting us.

​South Twin Reef provided a gentle but vibrant reintroduction to the water. The reef was alive with colour: Chromodoris annulata, Halgerda tessellata, Flabellina rubrolineata, Risbeccia pulchella, Phidiana sp., and dotted the granite boulders like confetti.
Macro life was already hinting at what was to come — a richness that would only intensify as the expedition progressed.

​Peacock mantis shrimps guarded their burrows while Durban dancing shrimps waved from ledges. Schools of lined surgeonfish and ringtail surgeonfish crossed paths with neon and yellowback fusiliers, while dogtooth tuna patrolled the deeper blue. Giant moray eels observed quietly from their lairs, and cuttlefish drifted over coral bommies. A juvenile scribbled filefish was even spotted feeding on a jellyfish, while egg cowries displayed their striking mantles.

​The macro parade continued with Macropharyngodon flasher wrasses darting across the reef.
At North Twin Reef and Bay, more treasures appeared: Halgerda tessellata, orange-tip Flabellina, and schools of five-lined snappers weaving through hard coral formations. Blue-tooth triggerfish, black-lined surgeonfish and pufferfish added movement, while spotted worm sea cucumbers and schooling squids completed the scenery.

​The night dive brought theatre. Octopus hunted across the reef, squids flashed past our lights, and jellyfish sheltered tiny fish. Parrotfish and triggerfish slept wedged securely into the rock, their trigger spine locked to prevent predators from pulling them free. Marble shrimps, spider decorator crabs, Elysia marginata, desirable Flabellina and Flabellina exoptata were everywhere, while a fimbriated moray eel slipped silently through the darkness. A spearing mantis shrimp was seen actively hunting, and pygmy squid hovered near the sand.

​Black Rock once again proved why it is considered one of Myanmar’s signature dive sites.
Currents carried vast schools of blacktip, bluefin, golden and bigeye trevallies alongside rainbow runners and longnose emperors. Barracudas formed shimmering walls in the blue, while eagle rays cruised past and coral, peacock groupers hovered above the reef.

​Macro lovers were equally rewarded: Bornella anguilla, Hypselodoris carnea, Cuthona Sibogae and a rare red frogfish, bearded scorpionfish, trumpetfish, rabbitfish and multiple cowries including tiger, money and mole cowries decorated the slopes.

​Cleaner shrimps and peacock-tail anemone shrimps worked tirelessly at their stations.
The sunset dive turned unforgettable when two oceanic manta rays appeared, circling gracefully over the pinnacle.

​Meanwhile, blackwater divers discovered larval seahorses, eel larvae, larval lizardfish, pyrosomes and delicate jellyfish drifting in the darkness, along with larval coral fragments suspended like tiny constellations.

​Shark Cave and the surrounding reefs proved to be outstanding territory for macro enthusiasts. Nudibranch diversity was exceptional, featuring Goniobranchus annulata, Goniobranchus geometrica, Goniobranchus conchyliatus, Thorunna horologia, Hypselodoris maculosa, Glossodoris cincta, Favorinus mirabilis, Phestilla melanobranchia, Dermatobranchus fortunatus, Bornella anguilla, and several Coryphellina species including Coryphellina exoptata.

​Our divers were also able to encounter bamboo shark hiding in the boulders, tigertail seahorses, tapestry shrimp, schools of neon and yellow back fusiliers, banded snake eel hunting,

​The night dive revealed zebra moray eels, massive hermit crabs, sea urchin crabs, Moridilla brocki, broadclub cuttlefish,hunting pygmy squid and hunting bamboo shark.

​Rainbow Bank delivered exactly what divers hope for here: nurse sharks resting beneath bommies, marble rays cruising by and mangrove whip rays lifting from the sand. Powder-blue and lined surgeonfish mingled with oriental sweetlips and two-spot butterflyfish, while coral and peacock groupers guarded the reef.

​Anthias clouds brought colour to the slopes, including scalefin anthias, flame anthias and redbar anthias darting above yellow saddle goatfish. Cleaner wrasses and sixline wrasses hovered around cleaning stations, joined by silverstreak anthias shimmering in the current.

​At Coral Bank, action intensified with large schools of giant trevallies and jacks, black-and-white giant snappers, five-lined snappers and chevron barracudas. One lucky group even witnessed two nurse sharks mating, a rare and powerful encounter.
Blackwater divers later enjoyed larval flounders, mantis shrimp larvae, drifting salps, translucent jellies and tiny crab larvae.

​More giant trevallies cruised above Coral Bank while neon and yellowback fusiliers blanketed the reef. Silvertip sharks appeared alongside resting nurse sharks, creating classic Banks scenery.

​At Silvertip Bank, a rare trio of oceanic triggerfish surprised everyone, accompanied by a passing Napoleon wrasse, filamented blennies and fire gobies. Blue-ringed angelfish, regal angelfish, Indian mimic surgeonfish, bird wrasses and bullethead parrotfish rounded out the reef community.
Blackwater once again delivered magic with larval barracudas, flying fish larvae, shimmering Venus girdles, pelagic thecosomes, shrimp larvae and ribbon-like Tomopteris worms.

​Sea Fan Forest felt like drifting through an underwater cathedral, where giant purple sea fans framed the reef and currents carried constant movement through the water column. Schools of yellowback and neon fusiliers streamed above the slope while golden trevallies patrolled the blue. Pickhandle barracudas hovered in loose formation and passing mackerel injected sudden bursts of speed into the scene.
On the reef itself, the resident stonefishes, blue-ringed angelfish, Chelidonura hirundinina, regal angelfish, anemone crabs and oriental sweetlips moved between coral outcrops as bird wrasses and powder-blue surgeonfish grazed along the hard coral ridges.

​Macro highlights included Glossodoris cincta, Goniobranchus geometrica, Phyllodesmium poindimiei, and Pteraeolidia semperi, alongside mating broadclub cuttlefish — a reminder that even on the most dynamic reefs, extraordinary small life thrives.

Few sites in the Mergui Archipelago rival Western Rocky when conditions, marine life, and curiosity align:
The Cave revealed Goniobranchus geminus, , Halgerda tessellata, Halgerda willeyi, multiple drifting blue dragons, a striking Phyllidia species, and several Unidentia. Around them, swirling fusiliers drew in hunting giant trevallies while lionfish hovered beneath overhangs and titan triggerfish cruised the perimeter.
 
Beyond the Cave, the Islets offered a different atmosphere altogether. Clouds of neon and yellowback fusiliers cascaded over the reef while scissortail fusiliers shimmered in the current. Bluefin trevallies swept through the schools with effortless precision, occasionally scattering them into flashing silver ribbons and maldivian sponge snails gliding on the reef.
Sharp-eyed divers continued their macro hunt, discovering several well-hidden nudibranchs, Thorunna australis, among the rubble as lionfish hovered motionless near the rocks and porcupinefish cruised calmly through the shallows.
At Eagle’s Rock, the dive delivered one of the most memorable sightings of the day, a beautifully camouflaged clown frogfish perched quietly on the reef, perfectly still yet impossible to ignore once spotted. Nearby, Spanish mackerel sliced through the water column while triggerfish patrolled the rocky edges, adding to the sense of constant movement.

Our final morning unfolded inside the sheltered amphitheatre of Shark Lagoon, a dramatic horseshoe-shaped formation carved by ancient geological forces rather than volcanic activity. Hard coral gardens climbed the slopes while sponges and soft corals painted the rock in vivid colours.
A shy blacktip reef shark cruised through the lagoon as a pregnant tiger-tail seahorse clung gently to the reef. Spirit mantis shrimps guarded their burrows while Clark’s anemonefish defended their homes. Blue-ringed angelfish, threadfin butterflyfish and a curious coral grouper completed the scene alongside boxer shrimps and a watchful fimbriated moray.
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We look forward to welcoming you on The Smiling Seahorse and show you all the wonderful moray eels of the Andaman Sea in Thailand or Myanmar.
For more info about what can be seen from our cruises, refer to our Andaman Sea Marine life page.              ​

​Remote, wild and wonderfully unpredictable, this expedition through the Mergui Archipelago and out to the Burma Banks delivered the full spectrum of Andaman diving. From open-ocean giants to minute macro masterpieces, the week unfolded as a constant contrast between power and precision, blue-water encounters and slow, detail-driven exploration.

​After clearing Thai immigration at Badin Pier in Ranong, we welcomed an international group of guests from Switzerland, Israel, France, Germany, the Netherland, the USA, Norway and Finland. A smooth crossing to Kawthung allowed us to complete Burmese immigration before setting course north into the Mergui Archipelago.
As the mainland disappeared, jungle-covered islands emerged on the horizon, hinting at the untouched reefs ahead. Quiet anchorages, mangrove-lined bays and the feeling of true exploration set the tone for the days to come.

Our first dives at South Twin Reef offered a gentle re-entry into the underwater world, blending colourful reef life with outstanding macro. Walls were decorated with Flabellina species and Chromodoris annulata, while squat shrimps and Durban dancing shrimps shared crevices with peacock mantis shrimps. Schools of lined surgeonfish and ringtail surgeonfish cruised steadily above the reef, joined by clouds of neon and yellowback fusiliers.
Out in the blue, dogtooth tuna made fast passes, while giant moray eels watched from their lairs and batfish hovered calmly above coral bommies. Tiny juvenile anemonefish added delicate movement among soft corals and sea anemones.

Dive three at North Twin Reef shifted the balance slightly toward larger reef predators. Octopus activity was constant, giant moray eels dominated the cracks, and powder-blue surgeonfish, coral groupers and titan triggerfish patrolled the reef. Macro lovers were rewarded again with Chromodoris annulata, Halgerda species and Flabellina nudibranchs tucked into the reef structure.
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The night dive in North Twin Bay brought a dramatic change of pace. Octopus and cuttlefish hunted actively, squid hovered in midwater, jellyfish sheltered juvenile fish, and big red reef crabs marched across the sand. Scorpionfish and bar-tail moray eels emerged, while parrotfish and triggerfish slept wedged into the rock, trigger spines firmly locked in place.

A full day at Black Rock delivered the classic mix of adrenaline and detail that defines this iconic site. Morning dives were highlighted by curious oceanic manta rays circling gracefully above the pinnacle. Around them, schools of chevron barracuda, blacktip trevallies, bluefin trevallies, golden trevallies and bigeye trevallies formed shifting walls of silver.

On the reef itself, coral groupers and peacock groupers shared space with powder-blue and velvet surgeonfish. Giant moray eels and yellow-edged moray eels filled the cracks, while batfish lingered in the lee of the current. Neon and yellowback fusiliers formed dense, constantly moving clouds around the rock.
Macro life was just as intense: Bornella anguilla, Goniobranchus geometrica, white-bump sapsucking slugs, golden wentletrap snails, tiger cowries, peacock-tail anemone shrimps and broadclub cuttlefish expertly camouflaged on the seafloor.
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The night dive revealed yet another side of Black Rock. Pygmy squid hunted small shrimps, devil scorpionfish lay in wait, and bar-tail moray eels cruised openly. Tiger cowries, money cowries and mole cowries dotted the reef alongside basket stars, sea cucumbers and massive hermit crabs. Moridilla brocki and slender Roboastra added vibrant flashes of colour to the darkness.

At Three Islets, we explored Submarine, Shark Cave and Square, enjoying a rich mix of reef fish and macro highlights. Bamboo sharks rested under ledges, while cleaner pipefish and orange-spotted pipefish hovered above soft corals. Schools of neon, yellowback, slender and twin stripe fusiliers streamed past chevron barracuda and passing trevallies.

At Shark Cave, tomato anemonefish and Clark’s anemonefish guarded their homes alongside anemone crabs, while white-eye and honeycomb moray eels patrolled the reef. Macro finds included Nembrotha lineolata, Cuthona sibogae, mouthbrooding cardinalfish and Chromodoris annulata.
Square delivered tiger-tail seahorses, orange-spotted pipefish, batfish, yellowtail barracuda and golden trevallies, with Goniobranchus geometrica, egg cowries and juvenile seahorses tucked into the reef. A Khul’s stingray glided silently across the sand.

The night dive was packed with life: blunt decorated crabs, cone snails, princely cones, tiger cowries, gorgonian crabs, juvenile cuttlefish, marble rays hunting, basket stars, sleeping filefish, toadfish and hunting moray eels.
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After the final dive, we headed west toward the Burma Banks, isolated seamounts rising from deep water and famous for shark encounters and wide-open pelagic scenery.

At Row Bank, adult and juvenile nurse sharks dominated the scene, resting on sandy ledges and cruising slowly along the reef. Powder-blue and lined surgeonfish mixed with oriental sweetlips and two-spot butterflyfish. Coral groupers and peacock groupers held position near the reef, while cleaner wrasse and sixline wrasse worked constantly. Basslets hovered close to the reef face, and yellow-saddle goatfish sifted the sand.

Rainbow Bank continued the shark theme, with more nurse sharks, schools of humpback unicornfish and sleek unicornfish, batfish, longnose emperors and large schools of black-and-white snappers mixed with giant one-spot and five-lined snappers. Great barracuda patrolled the blue, while honeycomb moray eels filled the cracks.
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Due to weather conditions, we made the decision to head back toward the archipelago, trading open ocean for shelter and macro-rich reefs.

The morning began at Volcano, also known as Shark Lagoon. Inside the lagoon, hard corals framed the dramatic rock amphitheatre, while colourful sponges and soft corals painted the walls in yellow, orange, pink, purple and green. Spirit mantis shrimps guarded their burrows, Cuthona sibogae and blue dragons crept across the reef, and tiger-tail seahorses clung to gorgonians.
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Western Rocky, including the Islets, the Cave and Eagle’s Rock, delivered classic big-and-small contrasts. Schools of trevallies, fusiliers and yellowtail barracuda swept past lionfish, scorpionfish and titan triggerfish. Giant moray eels filled the Cave, alongside Glossodoris hikuerensis, Risbecia pulchella, Bornella anguilla, Hypselodoris decorata, blue dragons and octopus. Five-lined snappers filled the chamber, while the Islets revealed harlequin shrimps, honeycomb and leopard moray eels and flashing flasher wrasses.

At Sea Fan Forest, towering purple soft corals and massive sea fans framed a thriving reef. Giant stonefish rested among the bases, while sleeping giant moray eels, rainbow runners and golden trevallies passed through the forest of fans. Schools of neon and yellowback fusiliers streamed overhead, joined by coral and peacock groupers, wrasses, blennies, parrotfish and triggerfish.

Macro highlights were abundant: Bornella anguilla, juvenile and adult Chelidonura punctata mating and laying eggs, Goniobranchus collinwoodi, Glossodoris cincta, Goniobranchus geometrica, devil scorpionfish, mating pharaoh cuttlefish, zebra moray eels, banded sea snakes, octopus and ornamental nudibranchs.
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Some divers opted for a blackwater dive, encountering juvenile squids, larval crustaceans, tiny jellyfish, larval triggerfish and drifting eel larvae glowing in the darkness.

At Dendro’s Peak, giant, golden and bluefin trevallies hunted schools of juvenile and naked fusiliers. Rainbow runners sliced through the current, while stonefish, fimbriated moray eels and Chromodoris annulata decorated the reef. Common reef fish such as surgeonfish, butterflyfish, angelfish, wrasses and parrotfish filled the background.
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The following dives at Western Rocky focused heavily on macro. The Islets and Eagle’s Rock delivered Glossodoris rufomarginata, large Goniobranchus reticulata, Hypselodoris decorata, resting marble rays, maldivian sponge snails, Aldisa albatrossae and Bornella anguilla. The Cave continued the nudibranch parade with Glossodoris averni, polka-dot phyllidia and Phyllidiopsis species.
The day ended with our traditional BBQ and boat party under the stars.

Our final dive returned to Dendro’s Peak, where giant moray eels, Clark’s anemonefish, and schools of rainbow runners and trevallies provided a fitting farewell. Naked, neon and yellowback fusiliers, stonefish, banded, sea snakes filled the water column, while cowries and colourful nudibranchs such as juvenile goniobranchus annulata and gemini offered last macro moments.
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After surfacing, we headed back to Kawthung for Burmese immigration, shared a final drink at the Smile Bar, and returned to Ranong, closing another unforgettable Mergui Archipelago and Burma Banks adventure aboard the MV Smiling Seahorse.