Scientists Map Uncharted Deep‑Water Mountains and Reefs in Britain’s Caribbean Territories

First deep‑sea expedition beyond Caribbean shallows reveals new features – Researchers spent six weeks operating 24 hours a day, using cameras to dive to 6,000 m, discovering an underwater mountain range, a massive blue hole, and pristine coral reefs around the Cayman Islands, Anguilla and Turks and Caicos [1].

Survey covered ~25,000 sq km, documenting 14,000 specimens – The team recorded 20,000 photos, identified 290 marine taxa and nearly 14,000 individual organisms, including rare pelican eel, barreleye, and dragonfish, though further taxonomic work is pending [1].

Pickle Bank mountain rises from 2,500 m to within 20 m of surface – The uncharted ridge north of Little Cayman climbs steeply, its sides teeming with bright coral, gorgonian whip coral, and black coral, forming one of the region’s healthiest reefs protected by depth [1].

A 300 m‑wide, 550 m‑deep blue hole discovered near Grand Turk – The vertical sinkhole, possibly the Caribbean’s deepest, hosts sponges, large spatangoid urchins and diverse fish, contrasting typical barren interiors of such features [1].

Ancient black coral and 4 km reef confirmed off Anguilla – Local fishers’ reports led to verification of a 4 km reef with sponge gardens and millennia‑old black coral, indicating exceptionally pristine conditions [1].

Findings will inform UK’s marine‑protected‑area targets – CEFAS and island environmental agencies will use the data for biodiversity management and to meet the UN‑mandated goal of protecting 30 % of oceans by 2030 under the Blue Belt Programme [1].