St. Eustatius - The Ledge to Hangover

General benthic features

Across all 95 unedited frames the habitat is a bioeroded coralline-algal pavement of rounded mounds cut by white sand grooves (3, 18, 79, 80), stepping down at one point into a distinct vertical ledge 1.5-2 m high with a sand-floored undercut beneath it - the "Hangover" (44, 46-47, 59, 76, 89) (e.g., Image 2, Image 12, Image 16, Image 20, Image 22, Image 45).

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Gorgonians, not corals, build the visual structure: sea fans Gorgonia ventalina in dense stands (38, 40, 63, 77, 87), feathery sea plumes Antillogorgia, thick sea rods (Eunicea, Plexaurella, Pseudoplexaura), dark Plexaura-type rods, a black sea fan Iciligorgia (56-57), and whip-like wire coral (75) (e.g., Image 4, Image 7, Image 8, Image 9, Image 17, Image 19, Image 23, Image 24, Image 25, Image 26, Image 34, Image 43, Image 46, Image 48).

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Sponges are the other dominant: giant barrel sponges Xestospongia muta recur in almost every wide frame (12-13, 61, 68-70, 82), with brown tube and vase sponges (Agelas conifera), orange elephant-ear (Agelas clathrodes, 8, 37), maroon rope sponges (Aplysina cauliformis), pink-brown vase sponges (Niphates), orange ball sponges, and extensive blood-red to maroon encrusting sheets (e.g., Image 1, Image 6, Image 10, Image 11, Image 14, Image 18, Image 21, Image 28, Image 30, Image 32, Image 35, Image 36, Image 44, Image 49).

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One barrel sponge hosts an epizoic olive sponge inside its cavity (23-24) and another shelters a stout reef crab (21) (e.g., Image 3).

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Stony corals are small, scattered and dominated by brain corals: Pseudodiploria strigosa appears repeatedly as isolated domes and free-lying plates (16, 26, 52, 62, 64, 73, 85, 87, 93-94), with grooved-brain Diploria labyrinthiformis (93), plating Orbicella/Montastraea, olive foliose Agaricia, and small Porites astreoides, Porites porites, and Siderastrea (e.g., Image 33, Image 39, Image 40, Image 47).

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Bare gorgonian axes recur (7, 11, 27, 81), and macroalgae plus turf cover much of the pavement (e.g., Image 27).

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Coral cover

Coral cover: 2.9% — a blind Claude computer-vision point count of 88 of Anderson's unedited photographs (20 points per photo; water, fish, and obstructions excluded). Other computer-vision methods are listed in the method table. Coral cover: no value is published for this site.

Stressors

Frame 53 shows a massive colony with a bright white band of freshly exposed skeleton beside a sediment-covered dead center - active tissue loss, worth follow-up (e.g., Image 37).

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Fish and other fauna

Fauna: a Nassau grouper (91), great barracuda resting under the ledge (89-90), a schoolmaster snapper school tucked into the overhang (55, 69), porcupinefish (58), a large indistinct fish deep in the undercut (46-47), Bermuda chub (35), stoplight parrotfish, Spanish hogfish, blue tang, blue, and purple chromis, fairy basslets, a flamingo tongue snail Cyphoma gibbosum on a gorgonian branch (45), and a live queen conch photographed eye-to-eye (19-20) (e.g., Image 5, Image 29, Image 31, Image 38, Image 41, Image 50).

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Comparisons with other data

No independent survey was made at this exact site; the nearest ones are listed in the table below.

Dive record

Dived as the second dive of 24 Feb 2026, descending a mooring line through clear blue water (frames 1-2) onto low-relief reef.

Other notes

Stony corals are small, scattered and dominated by brain corals: Pseudodiploria strigosa appears repeatedly as isolated domes and free-lying plates (16, 26, 52, 62, 64, 73, 85, 87, 93-94), with grooved-brain Diploria labyrinthiformis (93), plating Orbicella/Montastraea, olive foliose Agaricia, and small Porites astreoides, Porites, and Siderastrea (e.g., Image 33, Image 39, Image 40, Image 47).