### BISA104 — Salomon
**CRD page:** [Salomon Islands Coral Survey Sites (Apr 26–30, 2015)](https://coralreefdiagnostics.com/salomon-20150426-to-0430)

**29 Apr 2015**
**GPS:** 5.30829°S, 72.26865°E
**Setting:** exposed emergent forereef, 29.7 m
**Coral cover:** 36.2% (3 formal transects, D2–D4; **algal cover 33.6%**) · **published image bleaching:** 31.5% — **the second-highest bleaching value of the 98 Chagos sites carrying one**
**Live hard coral cover across methods:** formal transects 36.2% · CoralNet points 24.2% · Coralscapes masks 25.7% (16 frames). These products have different sampling footprints and denominators and should not be averaged.
**Temperature:** 30.2 °C · **Salinity:** 34.2
**Photo review:** all 16 frames examined (two are blue-light/fluorescence frames — see Flag 2)
**Representative photos:** P4290910.jpg, P4290920.jpg, P4290931.jpg, P4290923.jpg, P4290889.jpg

BISA104 is an exposed Salomon forereef whose defining measurement is not its cover but its condition. At **31.5% published image bleaching it ranks 2nd of the 98 Chagos sites with a bleaching figure**, behind only BISA84 — and the photographs corroborate that ranking emphatically. Coral cover is a middling 36.2% (64th of 109) against 33.6% algae, but the assemblage is the richest of this batch with **29 non-zero coral genera**. ***Porites* leads at 12.61% of the benthos** — 35% of all coral recorded — then *Acropora* 8.49%, *Pocillopora* 5.59%, *Montipora* 2.79%, *Favia* 1.11%, *Pavona* 0.94%, *Goniastrea* 0.78% and *Symphyllia* 0.61%. Twenty-one further genera sit below 0.5%, among them *Stylophora*, *Cynarina*, *Isopora*, *Cantharellus*, *Mycedium*, *Plesiastrea* and *Hydnophora*. Non-coral invertebrates hold 20.4% of the benthos, crustose coralline algae 16.1%, turf 9.8% and bare substrate 9.8%.

**Cover is remarkably flat across depth while composition rotates.** D2 carries 34.2%, D3 35.1% and D4 39.1% — a range of under five points — but the lead genus changes: *Porites* dominates the shallows at **19.07%** on D2 and 12.45% on D3, while **D4 inverts to *Acropora* at 19.00%** with *Porites* down to 6.30%. *Pocillopora* is strongest shallow (7.37% at D2). Genus richness rises with depth from 18 to 22 to 21 codes. Unusually for this archipelago, the deepest band is both the highest in *Acropora* and the highest in cover, which is the opposite of the pattern at BIPB110 and BIPB61.

The reef surface is structurally heterogeneous. P4290889 and P4290895 show low to moderate relief with coral heads projecting from consolidated framework. P4290910 centres a broad, table-like colony spanning much of the frame and surrounded by smaller colonies of different forms. P4290920 shows a sediment pocket bordered by branching and massive colonies, while P4290922 through P4290924 document a denser outcrop with varied colony sizes. This is not a continuous table field but a mosaic of coral patches, encrusted hard bottom and small open spaces.

**Bleaching affects several colony morphologies, which is what makes the 31.5% credible.** The table-like colony in P4290910 is almost entirely white but retains detailed radial branches and surface structure. P4290920 shows a compact branching colony with coherent white tissue directly beside a brown branching colony, making the contrast especially diagnostic. P4290931 and P4290932 show pale lobate or thick-branched colonies at close range, and smaller white colonies recur in wider scenes. The distribution across growth forms and across both wide and close frames supports a site-wide stress event rather than a few anomalous colonies.

The white colonies generally retain intact tissue contours, which favours bleaching over recently denuded skeleton. Some carry small dark or reddish spots and local holes, but these do not form a consistent progressive lesion margin, so bleaching is recorded at high confidence while disease is not. Older dead substrate with algal or coralline overgrowth is present in the mosaic and is separated from freshly pale tissue by its darker, irregular, encrusted surface.

Fish occur throughout the sequence, including dark surgeonfish-like silhouettes and smaller reef fishes around the coral patches, but the frames do not support standardised abundance or richness estimates.

<b>Assemblage composition.</b> Formal surveys give 36.2% coral, 33.6% algae and 20.4% non-coral invertebrates, the coral led by *Porites* in the shallows and *Acropora* at depth across 29 genera. The photographs show a heterogeneous coral-and-framework mosaic — a very large table-like colony, compact branches, massive heads and lobate forms — with bleaching widespread and visually severe across multiple morphologies.

**Flags:** (1) **This is the second-most-bleached site in the archipelago at 31.5%.** The rank is computed from the published `Mean(%bleaching)` column, which carries at least one known bad value (BITB58 appears as 22.22% where the corrected figure is 0.77%), so the rank is approximate; the 31.5% itself is taken as published and is strongly corroborated photographically. (2) **P4290914 and P4290915 were photographed under blue-light or fluorescence illumination.** Their cyan-blue background and altered emission colours show that fluorescent tissue or pigment remains in parts of the colony, but they are **not comparable to standard-light frames for judging white versus pigmented tissue**, and no bleaching percentage or severity category is derived from them. Any future automated pass over this folder must exclude these two frames from colour-based scoring or it will produce a wrong answer. (3) **Photographic selection bias:** the close-ups deliberately target striking white colonies, so their frequency in the image set is not a random areal sample. The repeated pale colonies in the broad views are what establish that the condition was not limited to one subject. (4) **Frame count matches** (16 stills, `n_photos = 16`), but the three cover methods still differ by up to 12 percentage points — do not quote a single cover figure without the method. (5) No crown-of-thorns starfish was identified, no focal feeding scar was clear enough to classify as predation, and no diagnostic disease band or advancing tissue-loss front was seen.

**Benthic data:** [Download BISA104 benthic survey data (CSV)](../benthic_data/BISA104_benthic.csv) — scleractinian cover by genus with full names, plus substrate and algal categories (bare substrate, CCA, turf, macroalgae, invertebrates), from the LOF BIOT-1 survey (Mayfield & Dempsey 2026, *Oceans*, supplemental file S1).