Saba - Man-of-War Shoals

Setting

Basalt spires and pinnacles with narrow clefts and canyons between them, near-vertical walls dropping to pale sand and loose rubble aprons, and shallower crests that catch full sunlight (e.g., Image 16, Image 17, Image 25).

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General benthic features

Cover is overwhelmingly sponge and crustose coralline algae over dead framework (e.g., Image 8).

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Giant barrel sponges (Xestospongia muta) appear in dozens of frames — brick-red, salmon, and tan, several a meter across, one cluster of five or six grown together on the crest, several with torn or pale rims (e.g., Image 2, Image 11, Image 30).

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Golden tube sponges (Aplysina fistularis) form large stands on the shallow crests and orange elephant-ear sponges (Agelas clathrodes) punctuate the wall faces, with olive-mustard encrusting sheets, mint-turquoise sponges, dark red foliose sponges, gray and lavender vase sponges, and abundant scarlet encrusting sponge (e.g., Image 13, Image 14, Image 40, Image 44).

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Gorgonians include sea plumes, sea rods, black bushy colonies, and black-coral bushes silhouetted on the wall; green bushy macroalgae carpets parts of the wall and crest (e.g., Image 10, Image 15, Image 31, Image 38).

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Stony coral is present but subordinate. Great star coral (Montastraea cavernosa) gives the best colonies — several healthy domes with raised corallites, one with a turf-colonized dead patch (e.g., Image 22, Image 33).

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Grooved brain coral (Diploria labyrinthiformis) recurs as olive-green heads, in one frame a live colony sitting beside a dead turf-covered brain skeleton, two with small white patches that may be lesions (e.g., Image 53, Image 54).

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Plating star corals of the Orbicella type appear as crowded-corallite plates, one being overgrown by a sponge (e.g., Image 3, Image 27, Image 39).

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Agaricia plates, Porites astreoides knobs, a small branching coral stand, and green-striped corallimorphs (Discosoma) fill the cryptic spaces (e.g., Image 47).

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Coral cover

• Reference: Claude CV point count (this site's photos)
• Coral cover: 3.7% — a blind Claude computer-vision point count of 102 of Anderson's unedited photographs (20 points per photo; water, fish, and obstructions excluded). Other computer-vision methods are listed in the method table.
• Frames were screened before scoring: open sand, mid-water, blown-out, and burst-duplicate frames, dive computers, topside, and diver shots, blue-light fluorescence, and macros were all removed.

Stressors

One small massive colony has a dead, turf-covered center ringed by a narrow white band of bare skeleton at the tissue margin, a band of recent mortality, cause not stated (e.g., Image 56).

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Two frames show small white patches on grooved brain coral (Diploria labyrinthiformis) heads that may be lesions, a possible sign of disease; the photographs cannot establish the cause (e.g., Image 53, Image 54).

Fish and other fauna

Fauna included Caribbean reef sharks (Carcharhinus perezi) in four frames, two together on the wall; a small nurse shark under an overhang; a green turtle on the crest across three frames; a queen angelfish inside a barrel sponge; grunt and margate schools; heavy sergeant-major, blue tang, black durgon, creole wrasse, and chromis presence; a rock beauty, a grouper, a trumpetfish, a bearded fireworm, and crinoids (e.g., Image 18, Image 34, Image 48, Image 52).

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One invasive lionfish (Pterois volitans) was seen.

Comparisons with other data

We found no other surveys confirmed at this site as of 2026. If you would like to share yours, please email us.

Dive record

Man-of-War Shoals, Saba National Marine Park, was reviewed frame by frame from all 109 unedited stills of dive 2, 21 Feb 2026.