### BISP101 — Speaker's Bank
**CRD page:** [Speaker's Bank Coral Survey Sites](https://coralreefdiagnostics.com/speakers-bank)

**28 Apr 2015**
**GPS:** 4.79250°S, 72.34557°E
**Setting:** protected submerged lagoon site, 24.8 m (no detailed reef class published — see Flag 3)
**Coral cover:** 50.0% (2 formal transects, D3–D4; **algal cover 39.4%**) · **published image bleaching:** 7.1%
**Live hard coral cover across methods:** formal transects 50.0% · CoralNet points 26.7% · Coralscapes masks 31.2% (8 frames). These products have different sampling footprints and denominators and should not be averaged.
**Temperature:** 29.9 °C · **Salinity:** 34.4
**Photo review:** all 13 frames examined
**Representative photos:** P4280890.jpg, P4280903.jpg, P4280926.jpg, P4280912.jpg, P4280893.jpg

BISP101 is the most compositionally lopsided site in this batch and one of the most *Acropora*-dominated in the archipelago. Coral cover is 50.0%, 26th of the 109 Chagos sites, and ***Acropora* alone holds 41.50% of the benthos — 83% of all coral recorded***. Every other genus is a rounding error beside it: *Montipora* 3.36%, *Pocillopora* 1.93%, *Leptastrea* 0.61%, *Psammocora* 0.55%, *Porites* 0.53%, *Astreopora* 0.40% and *Favia* 0.36%, with *Pavona*, *Favites*, *Millepora*, *Cyphastrea* and *Montastrea* below that. Only **13 coral genera** are non-zero — the shortest list of these five sites, and a striking contrast with the 28 and 29 recorded at BISA103 and BISA104. Crustose coralline algae hold 19.5% of the benthos, turf 9.5%, bare substrate 8.5%, macroalgae 3.2% and non-coral invertebrates only 2.0%.

**Both depth bands are the same reef.** D3 carries 54.6% coral with *Acropora* at 42.40% across 13 genera; D4 carries 45.5% with *Acropora* at 40.60% across seven. Unlike every other site in this batch, the genus order does not rotate with depth — *Acropora*, then *Montipora*, in both bands. What changes is richness and algal cover, which rises from 33.7% to 45.0%. This is the one site here where the site-level mean is a fair summary of both transects.

Reef structure is broad and laterally continuous rather than vertically towering. Large golden-brown plates recur from the foreground to the limit of visibility, often overlapping or standing on short central stalks, creating repeated horizontal shelves a short distance above the substrate and leaving open corridors between colony bases. P4280890 and P4280891 show the field extending across the frame; P4280902 through P4280904 demonstrate that the pattern persists along the photographed route; P4280912 gives a close view of living table surfaces. Some plates appear thick and old, with irregular margins or localised dead patches; others retain fine radial branch texture and sharply defined edges.

The spaces between the tables matter ecologically. Low rubble, consolidated pavement and patches of brown or greenish growth form the understorey, with occasional small branching and massive colonies. Several plate surfaces carry small dark fishes while others pass through the shaded gaps, so the table canopy provides habitat at multiple horizontal layers. P4280893 contains a large gray animal beneath a table; its outline is compatible with a reef shark, ray or another large fish, but the head, fins and tail are partly obscured by the plate and the viewing angle, so it is recorded only as a large shark- or ray-like animal sheltering under coral.

Bleaching is limited compared with the severe Salomon sites but is present, and the published figure of **7.1% ranks 49th of 98** — squarely mid-range. The clearest example is P4280926, where a compact field of branching colonies is pale lavender to white while surrounding tables retain gold-brown pigmentation; the pale thicket remains structurally intact and the coherent colour difference makes bleaching convincing. A few white table margins elsewhere could be growth tips, localised tissue loss or lighting effects and are not individually flagged. P4280925 is a close view of a colony with visibly pigmented polyps and is deliberately **not** treated as a bleaching record — it illustrates why bright skeletal-looking texture alone is insufficient, since the close frame reveals living pigmentation and polyp detail that a distant view would obscure.

<b>Assemblage composition.</b> Formal surveys give 50.0% coral, 39.4% algae and 2.0% non-coral invertebrates, the coral 83% *Acropora* in both depth bands. The photographs document an extensive field of overlapping golden-brown tables above low pavement, rubble and vegetated patches, shaded refuge beneath the plates, and localised bleaching in one pale branching thicket.

**Flags:** (1) **Frame-count mismatch:** the folder holds 13 stills and all 13 were reviewed, but `chagos_multimethod_cover_by_site.csv` records `n_photos = 8` — the smallest photographic sample of any site in this batch. The CoralNet and Coralscapes figures rest on those eight frames; never present "13 frames" beside them. (2) **Only two formal transects (D3, D4)**, the thinnest survey replication of these five sites. (3) **The published detailed reef-type cell is blank for this site.** The setting line is built only from `exposure-revised` = protected, `lagoon` = inside, `reef emergence` = submerged and `reef location` = lagoon; **no more specific reef class has been invented**, and none should be added without a source. (4) **The three cover methods differ by up to 23 percentage points** (50.0% / 26.7% / 31.2%). (5) The image set strongly favours the most scenic feature — the table field — and holds fewer frames than neighbouring sites; the robustness of the table-forming interpretation rests on the 41.50% `ACRO` figure, not on the imagery. (6) No crown-of-thorns starfish was identified; no clear fresh feeding scar was visible; no progressive disease band, lesion margin or tissue sloughing could be diagnosed. Irregular edges, holes and dull patches on some tables are consistent with breakage and established partial mortality and are not classified as disease or predation. (7) **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 **7.10%, rank 57 of 110** (1st training: 7.10%, rank 56 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 BISP101 benthic survey data (CSV)](../benthic_data/BISP101_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).