Trip BB2629 Similan Islands

Trip Report – M.V. Blue Dolphin

Trip Leader: Sam
 | Location: Similan & Surin Islands

Day One – Similan Islands

We began the trip in the Similan Islands with excellent conditions and immediately impressive marine life density. The sites were extremely “fishy,” with large schools present throughout the dives. Green turtles were a constant highlight, with several individuals approaching the stern of the boat between dives, providing great surface interactions for guests.

Water temperatures varied noticeably with depth. While deeper sections introduced some cooler thermoclines, the shallows remained very comfortable, allowing for relaxed and extended dive profiles.

The sunset dive rounded off the day beautifully, offering a change of pace with a focus on macro life. Highlights included octopus, cleaner shrimp, and a variety of nudibranch species, all actively feeding as light levels dropped.

Day Two – Similan to Koh Tachai

An early start at North Point rewarded us with stunning conditions. The sunrise illuminated the granite boulder formations and vibrant sea fans, creating excellent visibility and atmosphere. A white tip reef shark sighting added to a strong opening dive.

We then moved to Koh Bon, where conditions were slightly darker than previous sites, but still rich in marine life with plenty of fish activity throughout the water column.

The standout of the day was Koh Tachai. Despite Pete’s best efforts to lose all of his gear, all divers entered safely and were rewarded with truly spectacular action. Massive, tightly packed tornadoes of barracuda and trevally dominated the site, creating one of the most memorable scenes of the trip so far. A turtle made a brief but welcome appearance on top of the pinnacle, adding to the excitement.

The final dive of the day coincided perfectly with slack tide at sunset. This brought an incredible aggregation of fish onto the top of the pinnacle, with peak activity and ideal viewing conditions, providing a fitting end to an exceptional day of diving.

Day Three – Surin Islands & Richelieu Rock

We started the day at Aow Pakkad in the Surin Islands with a gentle drift dive, providing an ideal warm-up for the dives ahead. Visibility was good, conditions were calm, and the relaxed pace allowed guests to settle in comfortably while enjoying steady marine life encounters along the reef.

The main event of the day was Richelieu Rock, which delivered exceptional conditions across all dives. Visibility remained strong, with a mild current that brought in constant pelagic and schooling action without making diving challenging.

Marine life highlights included ghost pipefish and ribbon eels, alongside large, active hunting schools moving through the site. The energy of the reef was consistent throughout the day, with excellent fish behaviour and density at all levels.

Overall, Richelieu Rock lived up to its reputation and then some!

Day Four – Koh Bon

Our final day took us back to Koh Bon, where conditions once again proved rewarding. The highlight of the day—and indeed the trip for some, was a rare and unforgettable encounter with an approximately 5-meter whale shark spotted along the West Ridge.

While not all guests were fortunate enough to witness it, those who did experienced an exceptional moment with one of the ocean’s most iconic species. The sighting was likely influenced by environmental conditions, with cooler water upwelling and rainfall from the previous night contributing to nutrient movement and attracting larger pelagic life to the area.

This remarkable encounter provided a memorable and fitting conclusion to a truly memorable trip.

To all the lovely people who joined us we’d like to say thanks for being legends and see you again very soon…

Sam and the crew on Blue Dolphin.