Alor - Goa Wolang (Walang Cave)

Setting

Frame by frame this dive splits into three habitats. Second, the cave: two frames show the entrance as a dark arch with a diver silhouetted in blue water, one looks back out at a bright triangular mouth (e.g., Image 16).

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Visibility was good, roughly 15-20 m.

General benthic features

First, a shaded overhang and boulder base carpeted in crustose coralline algae in magenta, rose, and red, studded with red, and orange encrusting sponges (e.g., Image 1, Image 6, Image 13).

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Coral here is overwhelmingly foliose and laminar, not branching: overlapping pale-brown plates with upturned, pale-edged margins compatible with Montipora and Turbinaria, small fleshy folded merulinid or lobophylliid polyps, squat Sarcophyton-type leather corals, and bushy orange Dendronephthya hanging from the roof with anthias beneath (e.g., Image 7, Image 9, Image 12, Image 21).

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Four torch-lit interior frames hold no zooxanthellate coral at all - only white, yellow, and salmon encrusting sponges, spaghetti-like sponge processes, bryozoan or serpulid crusts, and one solitary cup coral with a ribbed brown wall and a ring of pale swollen polyp vesicles, shot three times (e.g., Image 10, Image 14, Image 19, Image 22).

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Third and largest, an open low-relief pavement of coralline-crusted rubble, cobble, and dead framework - repeatedly the most extensive substrate in the set (e.g., Image 4, Image 5, Image 15, Image 20, Image 25).

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Live coral sits on it as isolated heads and patches: a tabulate Acropora beside a domed Montipora-type colony, a stout blue-gray branching colony with blunt tips, green-yellow digitate Acropora, meandroid Platygyra/Goniastrea-type brains, one large pale-green finely divided arborescent colony, feather stars, green turf, small gorgonians, a black long-spined urchin (e.g., Image 2, Image 18, Image 24, Image 28, Image 32).

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Coral cover

Coral cover: 7.7% — a blind Claude computer-vision point count of 28 of Anderson's unedited photographs (20 points per photo; water, fish, and obstructions excluded). Other computer-vision methods are listed in the method table.

Stressors

No bleaching, disease, or predation was evident - hard coral simply holds a minority of a mostly coralline-and-rubble surface (e.g., Image 29, Image 35).

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A metal cage or rebar frame with lines lies on the rubble, and a thin rope crosses three frames (e.g., Image 37).

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Fish and other fauna

Fish were anthias and Chromis swarms, blue damselfishes, a yellow Chaetodon, and orange soldierfish; two shallow frames climb a near-surface wall dense with orange cup-coral-like polyps (e.g., Image 11, Image 31, Image 36).

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Comparisons with other data

Also on record for this site: A rugged cave entrance and adjoining rocky reef with chambers and swim-throughs. Live hard coral cover was lower and more discontinuous than at the coral-garden sites, and the short sequence makes this primarily a topographic record.