Chagos Archipelago - Salomons Island (BISA102)

Setting

BISA102 is a deep exposed emergent forereef outside Salomon atoll at 32.8 m, surveyed 28 April 2015 (e.g., Image 1).

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General benthic features

Across 24 genera the assemblage is Porites-led rather than Acropora-led, Porites holding 46% of all coral, Pocillopora 20%, and Acropora only 11%. Down the profile the Porites share climbs steadily — 39%, 34%, 52%, 58% — while genus richness collapses from 22 genera at the best transect to just five at the deepest, where invertebrates take 39.0% of the ground.

Coral cover

Formal transects recorded 30.9% coral against 30.6% algae — 75th of 109 Chagos sites for cover, 87th for algae — but the number that defines the site is neither: non-coral invertebrate cover is 31.3% of the benthos, slightly more than the coral itself, and the photographs identify it as anemones with resident anemonefish, soft corals, encrusting sponges, gorgonians, and giant clams. Image methods read about 11 points below the transects (CoralNet 20.0%, Coralscapes 20.1%). Coral cover: 31%. Live hard coral measured on the in situ benthic transects of the LOF BIOT-1 expedition (Mayfield & Dempsey 2026, Oceans, supplemental S1), against algal cover of 30.6% of the benthos. The transect figure is this site's authoritative cover value; no image-derived product overrides it. Across methods the same reef reads: transects 30.9% · CoralNet points 20% · Coralscapes masks 20.1% (35 frames). These products have different sampling footprints and denominators and should not be averaged.

Stressors

Published bleaching is 19.2%, 8th of 98 on the site table's Mean(%bleaching) column, the first CoralNet training run rather than the canonical % bleaching (2nd training) column, and the imagery agrees: a branching colony stark white across every branch beside pigmented neighbors of the same size, three adjacent white colonies in another frame, a white corymbose colony against a healthy massive Porites (e.g., Image 3).

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No crown-of-thorns, disease, or predation was seen.

Fish and other fauna

A silvertip-type shark, two giant morays, and an octopus were photographed, and one frame is a blue-light fluorescence shot that must be kept out of any color-based scoring (e.g., Image 2).

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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.