Chagos Archipelago - Salomons Island (BISA107)

Setting

BISA107 is a deep exposed emergent forereef outside Salomon atoll at 34.75 m, surveyed 30 April 2015.

General benthic features

Across 25 genera Acropora holds 41% of the coral and Stylophora an unusually high 15%, while Porites is nearly absent at 4%. Cover more than doubles down the profile, 16.4% to 20.4% to 37.0%, Millepora confined to the shallowest transect, Stylophora peaking at the middle one, and Acropora surging to 55% of the coral at the deepest — yet algae outweighs coral at every depth.

Coral cover

Formal transects recorded 24.6% coral against 65.4% algae — 85th of 109 Chagos sites for cover, 2nd of 109 for algae — but that is not an overgrowth story: coralline algae alone holds 34.9% of the benthos, the highest such value of any of the 109 sites, against only 8.6% fleshy turf, so the dominant surface is cemented pink pavement rather than weed (e.g., Image 3).

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Image methods recover about half the transect cover (CoralNet 12.5%, Coralscapes 12.8%) and rest on just 12 frames from a fun dive. Coral cover: 25%. 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 65.4% 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 24.6% · CoralNet points 12.5% · Coralscapes masks 12.8% (12 frames). These products have different sampling footprints and denominators and should not be averaged.

Stressors

Published bleaching is 7.1%, at the archipelago median, 50th of 98 on the site table's Mean(%bleaching) column, the first CoralNet training run rather than the canonical % bleaching (2nd training) column; no colony in the 20 frames reviewed shows unambiguous white-against-pigmented contrast, and a pale coralline surface covering a third of the benthos makes any color-based call unreliable here. The most actionable observation is an abandoned fishing net photographed draped across live coral and pavement inside the BIOT no-take MPA. No crown-of-thorns starfish (COTS) or other corallivores evident.

Fish and other fauna

Three shark encounters and a spiny lobster were also recorded (e.g., Image 1, 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.