Raja Ampat - Shadow Reef

General benthic features

The blind Claude count scored 50 frames from this dive. The set opens in the water column rather than on the reef, which is characteristic of the site. Image 1, one of Anderson's own frames, is a diver finning over rounded massive Porites domes and low turfed substrate with bubbles trailing behind — the establishing shot.

1

Where the camera does come down onto the substrate, the reef is a low-relief, heavily encrusted, soft-coral-dense surface rather than a coral garden. Close reef-top frames show purple-brown encrusting and massive colonies interleaved with pale foliose plates over pink coralline pavement, a brown meandroid colony with foliose plates set in coralline, and a large pale foliose plate colony sitting proud of the encrusted pavement. One close-up from the dive holds a white arborescent soft coral, bright red encrusting sponges, coralline crust, small plating colonies, and crinoids in one frame. Gorgonians and soft corals are a recurring subject. Other frames show a tall brown lacy sea fan shot vertically against the murk, a pale sea fan on the reef with fusiliers behind it, a wall face carrying a blue sea fan, crinoids, and green encrusting sheets with a diver at the frame edge, and an orange-brown gorgonian on the reef crest with a diver in the blue behind. Image 4 is the standout: clusters of vivid magenta arborescent soft coral hanging off an overhang beside a delicate white lace-coral arch and an orange soft coral, over green encrusting sheets.

4

Elsewhere, pink soft coral and crinoids stand against a yellow-brown massive Porites dome, and red and cream soft coral covers a slope face with anthias streaming over it. The stony-coral highlights are concentrated in the table and plating zone. A broad yellow-green tabular colony fills the foreground of one frame with a blue sea star at its base, and the same yellow-green plating and tabular form recurs in different light; a large flat plate carries damselfish and anthias, with red sponge at its margin. Two frames show a single large green-yellow Acropora table, one of them from below with a diver above and a second table behind. A gray table stands on a narrow pedestal with an anthias cloud around it and a diver above. Image 5 shows further gray tables with crisp white active rims standing on rubble and encrusted pavement.

5

One dense stony-coral frame from the dive shows a stand of branching and digitate colonies packed together with anthias over them, and branching and corymbose colonies with white growing tips occur on the crest. Two big yellow-brown massive Porites bommies appear with fish clouds and a diver behind them. On this dive the benthos that is actually visible is low-relief encrusting and massive coral, foliose and plating colonies, scattered Acropora tables, and a great deal of soft coral, gorgonian, and sponge — consistent with Anderson's own note for this site that soft-coral cover exceeds hard coral cover.

Coral cover

• Reference: Claude CV point count (this site's photos)
• Coral cover: 17% — a blind Claude computer-vision point count of 85 of Anderson's edited photographs (20 points per photo; water, fish, and obstructions excluded). Other computer-vision methods are listed in the method table.
• The difference between the two dives' counts (Dive record, below) is a useful indication of how much a single photo-derived dive index can move at one site.

Stressors

The photo review saw no bleaching, disease lesions, crown-of-thorns, or debris; however, a computer-vision point count called 0.5% of coral points bleached (1 of 85 photos). On dive 12, one branching colony carries about 15 stark-white bare patches on its branch tips, recent mortality, cause not stated (e.g., Image 46).

46

Fish and other fauna

Several large disc-bodied batfish hang in mid-blue over an encrusting, orange-tinged reef edge. Many frames are essentially all water: clouds of small planktivores against deep blue, a pair of barracuda (e.g., Image 12), dim large-fish silhouettes, and the whole seamount reduced to a silhouette in the haze with fish clouds over it.

12

One frame shows a cornetfish in open blue. Fish dominate the remainder. A large silver jack swims with two blue-finned trevally alongside; schools of yellow-bodied snapper and fusiliers work over the reef edge; two silver jacks pass over a pale gorgonian; and fusiliers and a trevally cross open blue. Image 3 is a striking fish frame — a diagonal-banded sweetlips hanging over rubble with a shimmering wall of thousands of glassfish filling the entire background — and another frame shows the same glassfish mass from below, the reef slope barely visible through it. Image 17 looks along a hazy reef slope through a dense cloud of orange anthias, with small baitfish massed in the blue beside it.

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One of Anderson's frames is a baitfish cloud filling the frame with larger predators cruising through it, and another is a shark in the blue with a diver at the right edge.

Comparisons with other data

We found no other surveys at this site as of 2026. Within 5 km, two Social Ecological Research Frontiers (SERF) / University of Rhode Island (URI) / Thriving Oceans stations recorded station-year means of 36–43% hard coral cover in 2019; the nearest, Social Ecological Research Frontiers (SERF) / University of Rhode Island (URI) / Thriving Oceans at Warakareket East, 3.28 km away, read 36% in 2019.

Regional context, not a survey of this site: Razak et al. (2026) found no significant trend in hard coral cover at Misool (a rise of 0.2% per year at eight sites, surveyed by point-intercept transect at about 8–10 m in 2009, 2010, 2011, 2013, and 2015 by Yayasan Konservasi Alam Nusantara); this is a trend for that location, not this site’s cover.

Dive record

Dive 12 — Shadow Reef, 18 October 2018. Anderson dived this seamount twice: dive 12 on 18 October 2018 (06:42, 56 minutes, to 28.6 m, dive-computer minimum water temperature 27.0°C) and dive 20 on 20 October (07:01, 62 minutes, to 33.2 m, dive-computer minimum 28.0°C); no average temperature exists for either dive. Both dives are described together here. The blind Claude count gives 19% for dive 12 (18 Oct, 50 photos) and 13% for dive 20 (20 Oct, 35 photos). That 6.0-point gap is variation between two dives — different depth tracks, different light, different framing on a large seamount — not a change in the reef over 48 hours. The second dive, at dawn on 20 October, read much the same way. A large share of its 51 frames are open-water fish shots — a tight school of jacks, fusiliers rising through blue water, backlit frames looking up toward the surface through curtains of small fish — and the clearer reef frames come later in the dive as the light built: large tan-gray massive Porites-type domes, big plating and table colonies with snapper streaming over them, and encrusting coral and sponge pavement. Its fauna matches Anderson's log: two close portraits of a large humphead (Napoleon) wrasse, banded barracuda, schools of trevally and fusiliers, a grouper, and a shark in the blue whose species cannot be resolved. None of its frames shows bleaching, crown-of-thorns, disease, or anchor damage.

Other notes

The open-water frames record what the site is famous for — the fish — but they carry almost no benthos, and that matters for the cover figure above. The frames are not a fish survey and cannot quantify the biomass they so obviously show.