Chagos Archipelago - Salomons Island (BISA107)

Setting

BISA107 is a deep side-on fore reef outside Salomon atoll (from its position on the northeast side of Salomon atoll relative to the prevailing southeast trade winds), surveyed 30 April 2015 on a dive to 30.8 m.

General benthic features

Across 25 genera Acropora holds 41% of the coral and Stylophora 15%, while Porites is nearly absent at 3.5%. Cover more than doubles down the profile, 16% to 20% to 37%, Millepora confined to the shallowest stratum, 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

• Reference: Mayfield & Dempsey (2026)
• CoralNet submission package
• Formal transects recorded 25% coral against 65% algae, but that is not an overgrowth story: coralline algae alone holds 35% of the benthos, 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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• Transect mean 25 ± 4.3% SE (n = 6 transects; Living Oceans Foundation per-transect benthic data); the headline above is this all-transect mean, and the published station value, which weights each depth equally, is 25% (Mayfield & Dempsey 2026, Oceans, supplemental S1).
• Live hard coral measured on the in situ benthic transects of the LOF BIOT-1 expedition (the mean of all of this station's transects), against total algal cover (all algal groups) of 65% of the benthos.
• Image-based estimates (CoralNet, DINOv3, CoralSCOP, and Claude) are listed in the method table for comparison only; the transect figure is this site's cover value.

Stressors

Published bleaching is 7.1% (CoralNet analysis of the survey images; Mayfield & Dempsey 2026, suppl. S1). The photographs show stark-white branching colonies beside pigmented massive and plating colonies and beside brown branching colonies of the same form in at least three frames (e.g., Image 7), although the pale coralline crust covering a third of the benthos makes color-based calls across the wider reef less certain.

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The most actionable observation is an abandoned fishing net photographed draped across live coral and pavement inside the BIOT no-take MPA (e.g., Image 10).

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The Living Oceans Foundation transects here recorded under 0.1% cyanobacteria and under 0.1% recently dead coral. No crown-of-thorns starfish (COTS) or other corallivores were 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

Apart from the Living Oceans Foundation survey shown here, we found no other surveys at this site as of 2026. Within 5 km, four independent stations recorded station-year means of 9.9–43% hard coral cover between 2006 and 2020; the nearest, XL Catlin Seaview Survey at transect 36014, 1.99 km away, read 34% in 2015.

Other notes

Anderson's field sheet (LOF fellowship 2016 workbook) records 'forereef' and leaves the aspect blank; the expedition's 933-site table classes the station as 'exposed' (fringing reef). No LOF habitat map covers Salomon atoll (the LOF Chagos habitat map covers only Peros Banhos), so, satellite imagery (Esri World Imagery) puts the pin off the northeast- to east-northeast-facing outer reef, near the side-on cutoff for the prevailing southeast trade winds. The aspect shown, 'side-on', comes from the station's GPS position on the northeast side of Salomon atoll relative to the prevailing southeast trade winds (about 86° off the upwind direction; the reef-edge reading agrees), which takes precedence over slope facing, lagoon shelter, imagery, and field labels.