### BISA94 — Salomon
**CRD page:** [Salomon Islands Coral Survey April 2015](https://coralreefdiagnostics.com/salomon-201504)

**25 Apr 2015**
**GPS:** 5.35038°S, 72.22001°E
**Setting:** protected (leeward) submerged lagoonal patch reef, inside Salomon lagoon, 19.0 m
**Coral cover:** 40.3% (3 depth strata over 15 formal transects, D2–D4; **algal cover 50.5%**) · **published image bleaching (`Mean(%bleaching)` column):** 2.8%
**Live hard coral cover across methods:** formal transects 40.3% · CoralNet points 36.7% · Coralscapes masks 28.7% (2 frames). These products have different sampling footprints and denominators and should not be averaged.
**Temperature:** 29.9 °C · **Salinity:** 34.3
**Photo review:** all 2 of 2 frames examined (the entire retained set for this site)
**Representative photos:** P4250837.jpg, P4250842.jpg

BISA94 is a submerged lagoonal patch reef inside Salomon atoll, surveyed at 19.0 m under leeward (revised: protected) exposure. It is a middling-cover, heavily algae-dominated site: **40.3% coral against 50.5% algae, ranking 50th of 109 Chagos sites for coral cover but 23rd of 109 for algal cover.** The composition of that algal budget is what sets the site apart. Fleshy turf (PTTS) alone accounts for **20.4% of total benthos — the 3rd-highest turf value of all 109 Chagos sites** — with macroalgae (PMTS) adding a further 17.6% and crustose coralline algae only 11.3% (70th of 109). This is the inverse of the well-grazed, coralline-pavement pattern seen at the exposed forereef sites: here "algae" means genuine fleshy turf and macroalgal growth, not encrusting pavement. Bare substrate (4.8%) and non-coral invertebrates (4.5%) are both low, so essentially the entire benthos is either coral or fleshy algae.

Coral cover is spread across **28 nonzero genera (32nd of 109 Chagos sites for genus count)**, and the 28 genus percentages sum to 40.257% of the benthos, an exact match to the published cover figure. All values below are percent of total benthos, not percent of coral. The assemblage is strongly massive- and fleshy-dominated rather than *Acropora*-led: ***Porites* 19.37% of the benthos (48% of all coral present) and *Goniopora* 10.90% (27%) together account for three-quarters of the coral at the site**, followed by *Lobophyllia* 2.58% (6%), *Heliopora* 1.19%, *Pavona* 1.10% and *Montastrea* 0.90%. *Acropora* is effectively absent at **0.086% of the benthos — one five-hundredth of the coral present**, an extreme for a Chagos site and a defining feature of this sheltered lagoonal setting. A tail of 22 further genera (*Goniastrea*, *Seriatopora*, *Halomitra*, *Montipora*, *Favites*, *Gardineroseris*, *Echinopora*, *Cyphastrea*, *Alveopora*, *Platygyra*, *Favia*, *Leptoseris*, *Turbinaria*, *Galaxea*, *Physogyra*, *Astreopora*, *Ctenactis*, *Herpolitha*, *Isopora*, *Fungia*, *Lithophyllon* and *Acropora* itself) each contributes under 0.8%.

**The three depth strata show a near-total collapse of the reef between 20 m and the deepest station, and the deepest stratum rests on a single transect — the single most important caveat at this site.** D2 (shallowest of the three) carries **63.2% coral against 26.2% algae**, with *Porites* at 28.86% of the benthos, *Goniopora* 18.26%, *Lobophyllia* 4.11%, *Montastrea* 2.71%, *Heliopora* 2.29% and *Halomitra* 1.43%, across 23 nonzero genera — a genuinely coral-abundant, structurally complex zone. D3 drops to **46.8% coral against 45.2% algae** and 16 genera (*Porites* 24.26%, *Goniopora* 8.63%, *Lobophyllia* 3.63%, *Pavona* 2.06%, *Goniastrea* 1.77%, *Heliopora* 1.29%). D4 then falls off a cliff: **10.8% coral against 80.0% algae, with only TWO nonzero genera on the entire transect — *Goniopora* 5.80% and *Porites* 5.00%.** Every other genus recorded at the site is absent from the deepest stratum. Because site cover is the unweighted mean of per-stratum means, that one 10.8% transect carries a full third of the headline number: **weighting the same data by transect instead (7 at D2, 7 at D3, 1 at D4) lifts site cover from 40.26% to 52.04%, a swing of 11.8 percentage points.** The published 40.3% is the correct figure under the standing protocol and is used throughout this shard, but it describes no depth at this site — the reef is either a 47–63% cover zone or a 10.8% algal plain, and the site number is an average of the two.

**Photographic documentation of BISA94 is the thinnest of any site in this set: two frames, of which only one is usable at reef scale.** P4250837 is a wide view of moderately high-relief patch-reef framework in slightly hazy water. A broad, open thicket of thin branching coral occupies the left and centre, while the right half and the foreground are built from rounded, knobby, mustard-yellow to tan lobate and massive mounds — a growth form entirely consistent with the *Porites*- and *Goniopora*-led transect ordering, though single-frame genus calls are not made here. Living coral is locally continuous, but darker shaded framework, older skeletal surfaces and open inter-colony spaces remain visible throughout, and dark olive-brown and maroon surfaces between colonies are compatible with the very high turf and macroalgal cover the transects record. A single surgeonfish-like fish crosses the upper right. P4250842 is an extremely close, soft-focus macro of branching coral tips with prominent radial corallites and pale pink-cream colouration; it supplies no site-scale habitat or condition information. Worth noting is that the one macro frame in the folder shows a branching acroporid- or pocilloporid-type colony from a growth form that the transects record at a fraction of a percent — a reminder that photo sets curated for the website select for visual interest, not for representativeness.

**Condition cannot be meaningfully assessed from two frames.** The published image bleaching figure is **2.8% (`Mean(%bleaching)` column; 82nd of 98 Chagos sites with a value — in the lower quartile of bleaching severity)**, and the two runs behind it agree exactly, so this is not one of the divergent bleaching-onset dives. Neither frame shows an unambiguous bleached colony: the branching thicket in P4250837 remains visibly pigmented, and P4250842 is too blurred and too close to distinguish pale living tissue from lighting, focus effects or normal pale-pink corallite colouration. No crown-of-thorns starfish, disease band, tissue-loss margin or discrete fresh feeding scar was identified. These are absence-of-evidence statements over two images, not a clean bill of health.

<b>Assemblage composition.</b> Formal transects give 40.3% coral against 50.5% algae — a turf- and macroalgae-dominated benthos with only 11.3% coralline pavement — across 28 nonzero genera led overwhelmingly by *Porites* (19.4% of benthos) and *Goniopora* (10.9%), with *Acropora* essentially absent at 0.09%. The three-stratum depth profile collapses from 63.2% coral at D2 through 46.8% at D3 to 10.8% at D4, where only *Goniopora* and *Porites* remain and algae occupy 80% of the benthos. The single usable photograph shows massive and lobate mound-building growth forms consistent with that ordering, on framework with substantial dark algal cover between colonies. With two frames retained, the imagery corroborates the transect assemblage but cannot characterise variation across the site or its condition.

**Flags:** (1) **The deepest stratum rests on ONE transect and moves the headline number by 11.8 pp.** Site cover is the unweighted mean of per-stratum means; D4 has a single transect at 10.8% cover against 7 transects each at D2 (mean 63.2%) and D3 (mean 46.8%). Transect-weighting the identical data gives **52.04%** instead of the published **40.26%**. The published figure stands under the standing protocol, but any downstream use of BISA94 cover should carry this caveat. (2) **D4 has only two nonzero genera on the whole transect** (*Goniopora* 5.80%, *Porites* 5.00%) and 80.0% algal cover — the most degraded stratum in this set of sites. (3) **Photographic evidence is explicitly inadequate**: two retained frames, one of them an out-of-focus macro. The site's structure, depth zonation and condition are not photographically documented, and no photo-based condition claim should be attached to this site. (4) **Fleshy turf is the 3rd-highest of all 109 Chagos sites at 20.4% of benthos**, with macroalgae adding 17.6% and coralline algae only 11.3% — an algae-dominated, weakly-grazed benthos, which is the site's most distinctive quantitative feature and is not visible in either photograph. (5) **`n_photos` = 2 in the multi-method table** — the CoralNet (36.7%) and Coralscapes (28.7%) figures rest on a two-image sample and are among the weakest CV estimates in the Chagos set. They should not be treated as independent confirmation of anything. Do not average them with the transect value. (6) **The CoralNet points figure is a CV product, not verified ground truth.** Point-annotation output corpus-wide is roughly 76% unconfirmed machine output. (7) **The published bleaching figure is a COMPUTER-VISION product, not an in-situ observation.** It comes from CoralNet annotation of the informal survey images (Mayfield & Dempsey 2026, *Oceans*). Per-image human-vs-model agreement is substantially weaker for bleaching than for cover: r = 0.40 for bleached against r = 0.72 for live hard coral (`CHAGOS_MULTIMETHOD_README.md`). Named column: `Mean(%bleaching)`, which equals the 1st CoralNet training run; the two runs agree exactly here (2.7778 vs 2.7778), so this site is not one of the ten divergent rows. Any rank quoted off that column is approximate, because it carries at least one known bad value (BITB58 listed at 22.22% against a corrected 0.77%). (8) **No COTS, disease or predation scarring was observed** in either frame — an absence over two images only, with no evidentiary weight. (9) **NON-CANONICAL BLEACHING RANK — added 2026-08-26.** Any "of 98" bleaching rank above was computed off the site table's `Mean(%bleaching)` column, which equals the **1st** CoralNet training run. Anderson's decision of 2026-08-26 (HOW_TO rule 4e) makes **`% bleaching (2nd training)` canonical**, The file carries TWO pools for it, and they are not interchangeable: a **110-row pool** ranking every dive (revisit dives included, so BIPB70B/72B/69C compete) and a **99-site pool** ranking one value per site. The rank quoted below is on the 110-row dive pool. For this site the canonical value is **2.78%, rank 91 of 110** (1st training: 2.78%, rank 91 of 110). The two runs agree to <0.05 pp on 100 of 110 rows and diverge only on the bleaching-onset dives, so for most sites the distinction changes the rank but not the number.

**Benthic data:** [Download BISA94 benthic survey data (CSV)](../benthic_data/BISA94_benthic.csv) — scleractinian cover by genus with full names, plus substrate and algal categories, from the LOF BIOT-1 survey (Mayfield & Dempsey 2026, *Oceans*, supplemental file S1).