Indonesia - Halmahera: Pulau Sebatang

General benthic features

Anderson's field note singles out the shallows, and the shallow frames carry dense coral. The dive descends onto a deep sand-and-bommie plain at 30–35 m: open pale sediment carrying isolated giant table Acropora, broad lavender and gray laminar Montipora/Turbinaria-type plates, and low bommies of Sarcophyton and Lobophytum leathers — the frames that produce the near-zero values (e.g., Image 13, Image 17, Image 33, Image 40, Image 43).

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The mid-slope is a mixed garden of foliose plates, Sinularia and Sarcophyton leather corals, cabbage-like Pachyseris/Merulina, massive Porites and Diploastrea-type heads, orange and crimson barrel and encrusting sponges, and bushy red-brown growths consistent with fleshy macroalgae or fine soft coral (e.g., Image 1, Image 5, Image 8, Image 9, Image 11, Image 15, Image 16, Image 21, Image 29, Image 41).

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Broad olive-green polyp mats consistent with Briareum-type soft coral or Goniopora carpet whole sections of the mid-slope pavement (e.g., Image 3, Image 32).

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The upper slope and reef crest are the site's signature: an essentially continuous Acropora field, tables, staghorn, corymbose, and digitate colonies packed edge to edge in mauve, lilac, orange-brown, cream, and olive, with Hydnophora, Pocillopora, Stylophora, Millepora-type fire coral, and Seriatopora filling every gap and clouds of blue-green chromis and anthias over it (e.g., Image 4, Image 7, Image 10, Image 14, Image 19, Image 20, Image 22, Image 23, Image 24, Image 26, Image 27, Image 28, Image 30, Image 46, Image 47, Image 48, Image 50, Image 51, Image 53).

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In the shallowest frames the surface is visible in the top of the picture and the coral runs unbroken to the edge of the field of view (e.g., Image 12, Image 54).

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Coral cover

• Reference: Claude CV point count (this site's photos)
• Coral cover: 41% — a blind Claude computer-vision point count of 265 of Anderson's unedited photographs (20 points per photo; water, fish, and obstructions excluded). Other computer-vision methods are listed in the method table.

Stressors

No unambiguously bleached colony was identified. A few colonies read conspicuously paler than their neighbors — a cream-white anastomosing colony in one frame and two thin white branching colonies in another — but at depth, without strobe, naturally pale coloration, bleached-alive tissue, and recently dead skeleton cannot be separated in the photograph, and neither frame shows a cluster. No crown-of-thorns, no Drupella aggregations, no disease lesions, and no rubble or standing dead thicket were recorded in the frames reviewed.

Fish and other fauna

Dense blue-green chromis, anthias, damselfish, wrasse, and parrotfish over the shallows; feather stars and a red crinoid or anemone on the crest; nothing larger resolved in the sampled stills.

Comparisons with other data

We found no other surveys at this site as of 2026. If you would like to share yours, please email us.

Dive record

Pulau Sebatang was dived on 10 August 2026 during the Halmahera crossing aboard the liveaboard Ambai (Wallacea Dive Cruises), reaching 35.1 m at 25–26°C.