N. GBR - Green (AUWO105)

Setting

Visibility was excellent throughout, with reef structure resolvable well past the foreground in nearly every wide frame. Anderson and his dive partner descended through crystal-clear water to about 15-20 m and were immediately engulfed by hundreds of jacks, barracuda, wahoo, and gray reef sharks. A 2-knot current permitted just one deep transect before a 10-15-minute upcurrent swim to a second wall.

General benthic features

The second half of the 59 frames shows the reef, and it is the substance of the set. At depth the terrain is a broad, gently rolling pavement built almost entirely of shingled tabular Acropora: plates well over a meter across overlapping one another edge to edge for the whole visible distance (e.g., Image 26, Image 27, Image 31), with staghorn and corymbose thickets filling the gaps and foliose scrolls tucked between (e.g., Image 32, Image 34).

2627313234

Down the slope the tables step down in tiers over plate and brain colonies, one with a feather star perched on its rim (e.g., Image 17, Image 19, Image 20, Image 38).

17192038

Staghorn thickets carpet whole stretches, in places blanketing the bottom edge to edge (e.g., Image 16, Image 30, Image 33), elsewhere mixing with tables, corymbose colonies, and a bright red corymbose colony (e.g., Image 25, Image 29), with bannerfish and butterflyfish working the branches (e.g., Image 40, Image 41).

16303325294041

Two vivid magenta-pink encrusting colonies stand out against the gray-blue of the deep frames (e.g., Image 32), and a salmon-pink plate and a rose-colored colony appear again on the upslope frames (e.g., Image 23, Image 45, Image 48).

234548

Other stretches of the slope are dominated instead by gray foliose and plating colonies (e.g., Image 18, Image 21, Image 24), and two frames show whole hillsides of ruffled, lettuce-like foliose colonies beside a large tan colony of the same ruffled form (e.g., Image 55, Image 56).

1821245556

Shallower and in better light the community broadens sharply. Seven frames are crowded corner to corner with growth forms in full color: mustard and lime corymbose Acropora, cream and tan tabular plates, knobby and smooth massives, brain-textured heads with meandering valleys, blue-tipped digitate colonies, olive branching thickets, encrusting sheets, and a pink barrel-form sponge (e.g., Image 42, Image 47, Image 49, Image 52, Image 53, Image 58, Image 59).

42474952535859

A lobed leathery soft coral sits among massive and plating colonies in one upper-slope frame (e.g., Image 43), and another pairs a bright yellow corymbose Acropora with an orange meandroid brain colony (e.g., Image 50).

4350

Two close-in frames carry the best colony detail: a large dark-olive coral of blunt, contorted, finely porous lobes with pale growing tips, wedged among gray foliose plates and digitate Acropora (e.g., Image 22); and a second of the same growth form pressed against a big tan colony with prominent conical surface bumps, with green corymbose Acropora and a brain-textured head at the edge of frame (e.g., Image 54) — both compatible with a branching Porites, but the photographs alone cannot settle the genus.

2254

Fresh white growing margins are visible on many tables and staghorn tips.

Coral cover

• Reference: Khaled bin Sultan Living Oceans Foundation, Global Reef Expedition (in situ transect)
• The frames cannot resolve the site's Seriatopora, which the dive account singles out, nor can they be read as a cover estimate — no cover figure is derived here from the photographs.
• On the second Wood Reef dive, the LOF transects recorded 61% live coral by point-count.
• Colors flatten toward blue in the ambient light at depth, but the structure is unmistakable, and Anderson's notes put his first transect, at 19.5 m, at 80-90% live cover amid dozens if not hundreds of species.
• Transect mean 61 ± 16% SE (n = 3 transects; Living Oceans Foundation per-transect benthic data); the headline above is the expedition's station value.

Stressors

No bleaching, no disease lesions, and no crown-of-thorns feeding scars are visible anywhere in the 59 frames; the pale patches that occur are the flattened blue-gray rendering of ambient light at depth rather than tissue loss. Anderson's notes record the needle coral Seriatopora hystrix on his 20 m transect as healthy.

Fish and other fauna

The first half of the set is pelagic: dense schools of jacks and fusiliers hanging over the drop (e.g., Image 1, Image 2, Image 3, Image 5, Image 6, Image 10), chevron barracuda stacked in ranks against the surface glare (e.g., Image 4, Image 8, Image 14, Image 35, Image 36, Image 37), rainbow runners and mackerel scad streaming past (e.g., Image 9), and two frames of the survey photographers themselves working inside a barracuda school with strobe-armed camera rigs (e.g., Image 11, Image 12).

1235610481435363791112

Reef sharks and schools of dark surgeonfish cruise low over the deep thickets and tables in several frames (e.g., Image 13, Image 15, Image 57).

131557

Comparisons with other data

No other surveys have been conducted at this site to date. Within 5 km, one independent station, XL Catlin Seaview Survey at transect 15001, 4.74 km away, read 20–22% between 2014 and 2017.

Other notes

Fifty-nine frames, and they document two distinct halves of the dive. One frame shows the survey transect tape running straight down that tabulate pavement, the yellow line crossing four or five separate plates in a single shot (e.g., Image 28) — the clearest picture in the set of what the transect was actually laid over.

28

Divers appear in three reef frames, twice holding a white PVC survey framer over the substrate (e.g., Image 7, Image 44) and once finning over a meter-scale plate colony (e.g., Image 51), which give useful scale.

74451

Two more frames add scale: a diver in open water beyond a steep face of massive and foliose colonies (e.g., Image 46), and a white PVC framer resting on the slope among plates and foliose colonies (e.g., Image 39).

4639