Raja Ampat - Nudi Rock

Setting

There was no current, and visibility was 20 m. The site is a sheer vertical wall at the base of a small island. The reef extends to about 20 m.

General benthic features

The wall is dominated by soft corals and sea fans, with some Pachyseris spp. At 15 m, reef dominated by soft corals, sea fans, and green Tubastraea (e.g., Image 5).

5

Seriatopora caliendrum was relatively common, here and in the surrounding area. There are large massive Porites colonies (e.g., Image 3).

3

Several species of plating corals grow here, including Montipora (e.g., Image 2).

2

Pocillopora verrucosa was present, along with a neon-green fluorescent soft coral. Stylophora pistillata was relatively common at 12–14 m. The framework is built by Porites and Pachyseris, with many foliaceous corals (e.g., Image 4).

4

Some areas are dominated by Tubastraea and soft corals instead of hard corals. Giant barrel sponges are common throughout the site. Coral biodiversity was high at 10–15 m. Lobophyllia, Sarcophyton, numerous species of brain corals, and a massive Porites species Anderson had never seen before were recorded.

Coral cover

• Reference: Claude CV point count (this site's photos)
• Coral cover: 30% — a blind Claude computer-vision point count of 97 of Anderson's edited photographs (20 points per photo; water, fish, and obstructions excluded). Other computer-vision methods are listed in the method table.

Stressors

One plating colony is half bleached: its right half is stark white, grading through cream into tan tissue on the left (one of Anderson's photographs, not shown). No disease and no other visible damage were recorded; elsewhere the corals carry full pigmentation, and the bright white rims on the plating colonies are growing margins, not mortality.

Fish and other fauna

Clouds of small fish surrounded the wall. Predators were fewer than at Four Kings at first but grew in number, density, and diversity as the dive progressed, with chubs and trevally chasing a bait-ball school. Fish life was staggering at 15 m. Anderson also logged a Napoleon wrasse, hunting chubs, a small (1.5-m) dogtooth tuna, and two gray reef sharks.

Comparisons with other data

Rijoly et al. (2026) surveyed this site (Nudi Rock). Within 5 km, five independent stations recorded station-year means of 8.2–30% hard coral cover between 2019 and 2026; the nearest, Social Ecological Research Frontiers (SERF) / University of Rhode Island (URI) / Thriving Oceans at Whale Rock Big, 0.40 km away, read 26% 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 17 of the trip, 19 October 2018 (entry 10:27, 62 minutes, maximum depth 15.4 m, single dive-computer water temperature reading 27.0°C): an awesome dive off a nudibranch-shaped rock.