Indonesia - Ambon: Laha-2

Setting

The third and muckiest of the Laha dives, 2018-04-22 -- overwhelmingly sand-silt bottom littered with dead shell middens and rubble, with almost no coherent reef structure (e.g., Image 4).

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Visibility ran mediocre and greenish, typical of a nutrient-rich muck site -- workable for macro, poor for wide shots.

General benthic features

Only two frames show coral at all (a small encrusting colony with healthy tan/orange, white-rimmed polyps, and a coral base beside a host anemone); this is a critter dive, not a coral survey, and the description here is scoped accordingly.

Coral cover

Coral cover — completed analysis, result rejected. CoralSCOP processed all 42 photographs and returned a raw mean computer vision estimate of 23.8% (SD 19; median=19.7%; range=0.0–65%). Full image-by-image review shows that this is not coral cover: the collection is overwhelmingly fish schools, cephalopods, frogfish, morays, anemones, sponges, shell rubble, and debris, with almost no hard coral in view. The model repeatedly segmented those non-coral subjects as coral. The 23.8% output is recorded here as a transparent failed-model result but is rejected for ecological interpretation; this site's coral-cover status remains not collected, which is more accurate than publishing a precise but false number. This CoralSCOP estimate is a placeholder while Anderson searches for a stronger coral-cover model; expect it to be updated if he finds one. Coral cover: 24% — a single-method photographic index. The figure is a CoralSCOP computer vision over Anderson's own photographs (42 frames), with no second method to cross-check it. CoralSCOP sums retained mask fractions with overlaps possible and segments coral-shaped objects rather than living tissue, so it scores standing dead skeleton as coral and does not measure cover the way a transect does; against in situ transects it reads high.

Stressors

Human-impact flag. A glass bottle and jar sit embedded in the shell rubble near the cuttlefish, tangled monofilament fishing line runs through several frames, and a PVC pipe fragment and fabric scrap lie beside one of the moray shots -- debris is woven into the substrate the critters are using as habitat, not an isolated piece of litter (e.g., Image 2, Image 3).

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No bleaching, disease, or crown-of-thorns observed, though with almost no live coral present this has limited scope.

Fish and other fauna

The macro life is excellent: harlequin shrimp, a shell-carrying octopus using bivalve halves as portable armor, resting cuttlefish (including one strobe-lit shot), at least four frogfish in different colors, two seahorses, four-plus moray eels (including a striking black-and-white speckled morph), a lionfish among tube sponges, a well-camouflaged scorpionfish, and two large bait-ball schools (e.g., Image 5).

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Comparisons with other data

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