United Caribbean (wreck, Fort Lauderdale)

The United Caribbean was dived 8 April 2022 as dive 1 of a two-dive Fort Lauderdale-area day (dive 2 was Rabbit Ears off Pompano Beach). The set is small and the water was poor, and what the frames actually show is a site dominated by large engineered structure standing on a sand and low-relief hardbottom plain — not a coral reef framework.

Structure is the subject of roughly two-thirds of the set. Image 6 is the clearest single frame: two heavily fouled vertical columns joined by a horizontal cross-member, standing intact and upright on sand — an engineered span, not reef rock (e.g., Image 6).

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Image 3 shows a single upright post or stanchion rising off the bottom in green water (e.g., Image 3).

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Image 1, shot in portrait, follows a thin encrusted linear member — a chain, cable, or slender rail — up through the water column, its whole length carpeted in fouling growth (e.g., Image 1).

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Image 5 looks along a long straight girder or hull edge receding away over a sand plain into the haze (e.g., Image 5).

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Image 10 shows large flat, uniformly fouled panels — hull plating or a similarly broad continuous surface — meeting sand at their base, with no relief or texture beyond the fouling layer (e.g., Image 10).

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Image 12 looks up under a beam framing more fouled structure (e.g., Image 12).

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Image 13 is a wide silhouette of a large angular collapsed mass, apparently a fallen superstructure or A-frame, seen at the edge of visibility (e.g., Image 13).

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Image 14 shows another fouled structural mound rising in green water, Image 15 fish over a debris field, and Image 16 another fouled structure (e.g., Image 14).

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Together these frames describe an artificial-substrate community: what has grown onto the structure, and fish using its relief.

What has recruited onto that structure is best seen in Image 2, the sharpest frame in the set: the exposed edge of an encrusted member carrying dense orange-to-mustard encrusting growth (encrusting sponges and/or colonial tunicates — the frame does not separate them), pink and red crustose coralline algae, red encrusting sponge, and small pale branching tufts consistent with hydroids or fine branching bryozoan, with a sergeant major hanging just off the edge (e.g., Image 2).

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This is a mature fouling assemblage, thick enough to obscure the underlying substrate entirely. Nowhere in the structural frames is bare metal or bare concrete visible; every engineered surface in this set is fully overgrown.

The natural bottom around and between the structure appears in four frames and is low-relief sand-veneered hardbottom rather than reef. Image 4 is a down-look over sand-dusted rock carrying small compact brown-yellow coral colonies — domed and only a few centimeters across, consistent with Siderastrea or a small Porites but not separable at this resolution, so neither is asserted — alongside green encrusting growth and pink coralline (e.g., Image 4).

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Image 7 is a close frame of the same kind of bottom: pink-red coralline and encrusting sponges, one small brown massive coral, a white sponge, and one small colony with white blotches, cause unclear (partial bleaching or tissue loss) (e.g., Image 7).

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Image 8 is the best benthic frame of the dive and the only confident coral identification in the set: a rounded orange-brown massive colony with large, widely separated, clearly resolved corallites, consistent with Montastraea cavernosa, sitting on sand-dusted hardbottom with a pink coralline rim and apparently intact tissue across the whole colony surface (e.g., Image 8).

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Image 9, in portrait, shows the sparse margin of this habitat — open sand, a low rock lip carrying red-orange encrusting sponge, and a handful of gorgonians and sea whips (e.g., Image 9).

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There is no Acropora, no thicket-forming coral, and no continuous reef framework anywhere in Anderson's 16 frames from this wreck.

Fish are present but the visibility keeps them incidental: a sergeant major on the structure edge in Image 2, a small butterflyfish under the beam in Image 12, an unidentified fish in midwater in Image 13, and a small yellow fish alongside the structure in Image 14. No divers, mooring lines, boats, fishing gear, or debris appear in any frame. One small colony in Image 7 carries white blotches, cause unclear (partial bleaching or tissue loss); it is a single colony in a single frame and is recorded qualitatively, with no bleaching or mortality figure attached and no event inferred. Coral cover: 3.8% — a blind Claude computer-vision point count of 14 of Anderson's edited photographs (20 points per photo; water, fish, and obstructions excluded). Other computer-vision methods are listed in the method table. On a wreck, low coral cover is expected.