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
Sac de Grand Case sits off Grand Case, on the French side of Saint Martin in the northeast Caribbean. The area lies along the island's Caribbean-facing coast near the town's small harbor, with boat access typically arranged locally. Divers here have reported Atlantic blue tang, sergeant majors, blue runners, Caribbean land hermit crabs, common lionfish, and slippery dick wrasse.
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.
Atlantic Blue TangAcanthurus coeruleusReported here · unconfirmed
Atlantic Sergeant MajorAbudefduf saxatilisReported here · unconfirmed
Slippery DickHalichoeres bivittatusReported here · unconfirmed
Blue RunnerCaranx crysosReported here · unconfirmed
Caribbean Land Hermit CrabCoenobita clypeatusReported here · unconfirmed
Common LionfishPterois volitansReported here · unconfirmed
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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