Chagos Archipelago - Danger Island (BIDI11)

Setting

BIDI11 is an intermediate-exposure submerged forereef outside the lagoon at Danger Island, published at 23 m and surveyed 12 March 2015 by the Living Oceans Foundation team.

General benthic features

It is the least genus-diverse site in the whole dataset, 4 genera and 109th of 109: Porites at 30.0% of the benthos, 75% of all live coral and the single highest Porites value recorded anywhere in Chagos, then Platygyra 6.0%, Favites 2.0%, and Stylophora 2.0%. The monodominance is probably real; the absence of everything else is not established, because the entire survey is one 100-point transect in one depth stratum, one of only two such sites in the dataset.

Coral cover

One formal transect recorded 40.0% coral against 21.0% algae — 52nd of 109 Chagos sites for cover, above the archipelago mean, but 107th of 109 for algae, third-lowest in the survey — with pavement at 51.0% and non-coral invertebrates at 30.0%, third-highest of the 109 sites and unresolved to taxon anywhere in the sheet. There is no depth profile, no range, and no standard deviation — the headline 40.0% is literally 40 points out of 100, and the four-genus result is four genera that happened to fall under them. That single transect is its only cover number. Coral cover: 40%. 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 21% of the benthos. The transect figure is this site's authoritative cover value; no image-derived product overrides it.

Stressors

Condition cannot be assessed: Anderson did not dive here, no photographs exist under any prefix or casing, there are no CoralNet or Coralscapes products, and the published Mean(%bleaching) cell is blank. No crown-of-thorns starfish (COTS) or other corallivores evident.

Comparisons with other data

No prior survey data from this site. If you would like to share yours, please email us.

Other notes

One conflict is unresolved and worth flagging — the published site table's "submitted to CoralNet" column reads "yes" for this site, while the CRD page says "did not dive", the comparison sheet says "formal surveys only", and nothing resolves to it. Either imagery exists somewhere and has been lost, or the cell is wrong.