Boulder Bay
Conditions & tides
Scored by DiveConnect's site-physics model
Marine forecast via Copernicus Marine. Score is a rule-based guide from swell/wind vs. the site's exposure — always dive your own assessment.
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About this site
Boulder Bay lies off Ko Rok Yai in the Andaman Sea, near Ko Libong off the Trang coast of southern Thailand, within the Mu Ko Lanta area rather than the Trat region on the Gulf side that the location string suggests. The island is known locally for granite boulder formations along its shoreline that continue underwater, and dive trips here typically launch from Ko Lanta or the Trang coast. Boulder Bay itself is rated a beginner site, and divers have reported octopus among the marine life around the boulders.
AI overviewMarine life here
Confirmed by our research team, reported by independent divers, or observed nearby via iNaturalist — each entry is labelled with its source.
OctopusOctopusReported here · unconfirmed
Moon WrasseThalassoma lunareReported here · unconfirmed
Greencheek ParrotfishScarus prasiognathosReported here · unconfirmed
Ocellaris AnemonefishAmphiprion ocellarisReported here · unconfirmed
Swarthy ParrotfishScarus nigerReported here · unconfirmed
Golden RabbitfishSiganus guttatusReported here · unconfirmed
Moorish IdolZanclus cornutusReported here · unconfirmed
Indo-Pacific Sergeant MajorAbudefduf vaigiensisReported here · unconfirmed
Indian Redfin ButterflyfishChaetodon trifasciatusReported here · unconfirmed
Checkerboard WrasseHalichoeres hortulanusReported here · unconfirmed
Blackspotted PufferArothron nigropunctatusReported here · unconfirmed
Tawny Hermit CrabCoenobita rugosusObserved near here · iNaturalist
Durable tips from divers — access, hazards, marine life, facilities. For day-of conditions, use the report tool in the conditions card above.
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