Philippines - Coron: Coral Gardens, Busuanga

Setting

Visibility was poor throughout; he labeled a frame terrible viz, which should temper any quantitative read of these photographs.

General benthic features

Coral Gardens is dominated by foliose and plating corals on a scale that fills nearly every wide-angle frame: overlapping whorls, scrolls, and shelves in tan, cream, and chocolate, most with clean pale growing margins, and among them colonies whose fine concentric ridging marks them as Pachyseris, the elephant-skin coral (e.g., Image 4, Image 5, Image 6, Image 7, Image 8, Image 9, Image 12, Image 14, Image 18, Image 22).

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One stand of plates is speckled a striking pink-red - dense pink-red polyps against pale skeleton (e.g., Image 11).

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Interleaved with the plate carpet are branching and staghorn Acropora thickets, tiers of tabulate Acropora tables, brain corals, a fleshy lobed Lobophyllia-type cluster, encrusting colonies, a blue-green soft-coral bouquet, orange soft corals, crinoids, and a large gorgonian sea fan (e.g., Image 1, Image 2, Image 13, Image 15, Image 16, Image 17, Image 19, Image 20, Image 21, Image 23, Image 24, Image 25).

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Anderson named three corals in his own filenames - Galaxea, Seriatopora, and Pocillopora acuta - an unusually specific and useful record; his Galaxea frames show colonies carpeting a sediment-veneered pavement. Genus richness is high.

Coral cover

Cover comes from two computer vision methods, neither preferred. DINOv3 point classification gives 35.1% hard coral from all 25 frames and 500 points (95% interval 32.6-37.6). CoralSCOP computer vision gives 25.6% from the 20 frames it scored; five were not returned. The spread is 9.5 points, widest of the three Coron sites, and the honest range is 26-35%. The frames explain it, and in the direction opposite to the wrecks: CoralSCOP scores the continuous plate carpets low - 11.7% on one frame, 12.8% on another, where DINOv3 reads 78.5% and 69.7% - because an unbroken sheet of plates offers a segmenter no colony edges, while it scores discrete objects high: 32.0% on a gorgonian sea fan, which is not stony coral. The two models fail differently. CoralSCOP computer vision reads high on low-cover reefs - a median=1.68x a co-located Reef Check diver survey, 4.6x at worst - but here it reads low, on high continuous cover. DINOv3 is strong in-domain (6-class macro-F1 0.62, hard coral recall 0.82) but collapses off-domain: cross-domain point accuracy 0.17-0.25, ceiling near 35-50% - and its 35.1% sits at that ceiling, so it may be a floor, not a value. Coral cover: 31% — photo-derived, and the two methods differ by 9.2 pp (35% vs 26%). This site's figure is the mean of two independent computer vision passes over Anderson's own frames: a DINOv3 calibrated point classifier reads 35.1% and a CoralSCOP computer vision reads 25.6%, a spread of 9.5 percentage points. The map publishes the mean so sites can be sorted against one another, but the honest statement of what is known here is the 26–35% range: the two products have different denominators and should not be treated as one measurement. Anderson is not done searching for a better coral-cover model than CoralSCOP and DINOv3, and this figure will be recalculated the moment he finds one.

Stressors

The reef reads healthy with no site-wide bleaching signal, though four frames carry localized white: a stark-white branch cluster, a pale lesion on one plate, two white pavement patches, and one bare Acropora skeleton. No crown-of-thorns starfish (COTS) or other corallivores evident.

Fish and other fauna

The blue and yellow animal logged as a chromodorid nudibranch reads at this resolution as a Polycarpa aurata ascidian - blue body, orange-yellow siphon rims - and is flagged for a closer check; a spotted synaptid sea cucumber shares the frame (e.g., Image 3).

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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

The third dive of 27 January 2017 and the only true reef of the Coron day - shallowest of the three at around 15 m, and the one with a real benthic signal; all 25 available frames were reviewed.