Indonesia - Halmahera: Failonga

Setting

Failonga is a small island off Tidore, dived on 9 August 2026 during the Halmahera crossing aboard the liveaboard Ambai (Wallacea Dive Cruises). Anderson's field note reads: "a small island normally with strong currents, black tip, turtle, lush foliaceous corals", and the photographs bear out the last phrase emphatically.

General benthic features

The dive's signature is a foliose plate garden: broad, pale olive-yellow whorled plates and vases, stacked several tiers deep and running for meters across the upper slope, with tabular and corymbose corals growing through them (e.g., Image 1, Image 8, Image 12, Image 18, Image 26, Image 28, Image 33, Image 40, Image 43).

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Below that, a bommie-and-sand slope carries isolated coral heads on open white sediment — the near-zero frames — with the bommies themselves crusted in crimson, orange, and ochre sponges, pink and mauve coralline algae, tan branching tube sponges, sea whips, gorgonian fans, and feather stars (e.g., Image 14, Image 22, Image 30, Image 34, Image 41, Image 46, Image 47, Image 49).

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A mixed branching zone on the mid-slope runs staghorn and bottlebrush corals, fine-branched corals, bushy branching corals, small branching corals, finger-coral stands, fire coral, and pink tree-like soft corals, and closes over into an almost continuous branching coral carpet on the upper reef in strong light (e.g., Image 2, Image 5, Image 10, Image 11, Image 13, Image 20, Image 21, Image 31, Image 37).

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The shallow crest is a low-relief pavement of corymbose corals and encrusting coral plates under clouds of anthias and chromis, and one soft-coral garden on the current-swept corner is packed with lilac, tan, and cream arborescent soft corals over the drop (e.g., Image 24, Image 27, Image 53).

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Coral cover

• Reference: Claude CV point count (this site's photos)
• Coral cover: 33% — a blind Claude computer-vision point count of 201 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

One extensive field of standing dead branching coral sits on the upper slope, the skeletons still articulated and bound by pink coralline algae and turf, with living branching corals, bushy branching corals, and soft coral recruiting through it — an old mortality event of unknown cause, not a recent one (e.g., Image 4).

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No unambiguously bleached colony appeared in the 29 frames examined (a random subset of the 219 on file); the two conspicuous white objects in one frame resolve on close inspection as an encrusting sponge and a shell or sponge disc, not bleached coral tissue. No crown-of-thorns, no Drupella aggregations, and no active disease lesions were recorded in those frames.

Fish and other fauna

A large long-tentacle mushroom coral with white-tipped tentacles was photographed close up (e.g., Image 29, Image 51), and anthias, chromis, damselfish, fusiliers, and butterflyfish were constant.

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The blacktip shark and the turtle from the dive log are not resolved in the sampled stills.

Comparisons with other data

Ibrahim et al. (2022) surveyed this site (Failonga Island, TTEL10) in 2021. In 2024, WCS Indonesia surveyed two stations, Tunguwai and Tomalou (MPA Mare 2024; data via MERMAID), recording 32–59% hard coral cover. Because this pin's position is approximate (an island-area anchor, not a dive-site fix), no station is compared with this site by distance; station names are not dive-site names.

Dive record

The dive reached 29 m at 26–27°C.