Indonesia - Komodo NP: Siaba Besar

Setting

Coral down to 20-22 m. 10 m viz, 26-27ºC. 10 m viz, very mild current.

General benthic features

Acropora, large, very old colonies (e.g., Image 1).

1

Stylophora, Seriatopora, Pachyseris, and numerous other lettuce corals. Coral assemblage at 5-10 m particularly rich. Merulina, plating Acropora, bottlebrush Acropora, Anacropora, murky, high sediment load, many corals feeding, some Acropora mortality. Enormous/ancient sheets of Pachyseris @ 15-20 m (e.g., Image 2).

2

Notable absence of Pocillopora. Large areas dominated by Acropora (e.g., Image 5).

5

Fluorescent green Stylophora very common at site (e.g., Image 4).

4

Some Fungia, Pavona, massive Porites (though not a major framework builder), fish life diverse but average size=small (e.g., Image 3).

3

Beautiful soft corals and sea anemones though this was definitely a hard coral-dominated site. Zoanthids and corallimorphs common. At least five species of soft coral. Finally saw Pocillopora verrucosa at the at the end of the dive @ 6 m. No Pocillopora damicornis/Pocillopora acuta. Pocillopora verrucosa, Seriatopora hystrix, Stylophora pistillata, Seriatopora caliendrum, Acropora (diverse and abundant), Pachyseris (dominant in places), Pavona (including a MONSTER colony), 5-6 large turtles over course of dive, several sharks resting on sand, cuttlefish. Hard coral-dominated site punctuated by large, sandy patches. Tons of large, foliaceous coral colonies, only one of which was Pachyseris. Cabbage/lettuce coral, with tons of huge branching Acropora colonies. Pavona, nurse shark, Euphyllia, 1 Culcita, several species of Galaxea (all small), Montipora, several species of brain coral, Hydnophora, finger Porites, small massive Porites (uncommon), Notable absence of Pocillopora acuta.

Coral cover

Coral cover: 53% — a blind Claude computer-vision point count of 121 of Anderson's edited photographs (20 points per photo; water, fish, and obstructions excluded). Other computer-vision methods are listed in the method table. Absolutely stunning hard coral cover. Very high diversity and cover @ 10 m. Anderson is still comparing computer-vision models, and these figures will be updated as the methods improve.

Stressors

Some Culcita damage, though not much.

Fish and other fauna

Several large, green turtles, one of which may have been pregnant. Pregnant turtles. Some garden eels in interesting sand apron. Tiny nudibranchs. NBS anemone (small), some algae in sand, Dictyota, some Acropora colonies. Saw a tiny frogfish (no good picture) and baby mantis shrimp (?) in sandy area, where we spent the last third of the dive.

Comparisons with other data

No independent survey was made at this exact site; the nearest ones are listed in the table below.

Dive record

2019-1-19 dive 1: Siaba Besar (#1). 7:28-8:33. Max. depth=19.2 m, dive time=65 minutes. 33% oxygen. 26ºC. 1st dive of the trip and one of the most well known for hard coral. 2019-1-26 dive 3: Siaba Besar (round 2; #30): 15:20-16:26 (66 min). Max. depth=16.2 m. Temp.=26.7ºC. 30% oxygen. Our second dive at this amazing site.

Other notes

Need to look up most common one (called it “Sinularia” though unsure). Need to check on the other species.