N. GBR - Green (AU74151)

Setting

The final dive of the day at Unnamed Reef 74 (his sheet: Unnamed Reef 166) covered a well-developed reef running to 25 m despite murky (~5 m) water, with live coral cover measuring 35% at this point within a site where several transects reached 60-80% cover, built on branching Porites and bottlebrush Acropora that carpeted patches at 100% cover (e.g., Image 1, Image 4).

14

General benthic features

Along the survey tape, lilac branching colonies and tan foliose plates grew over a pavement of small corymbose colonies, rubble, and pink crustose coralline algae, with the reef sloping away into blue water (e.g., Image 5).

5

Elsewhere the slope was a dense mix of bottlebrush, corymbose, and tabular colonies, small massive heads, and branching thickets running out to the limit of visibility (e.g., Image 7).

7

On the tape, a knobby lilac colony studded with small white polyps filled the frame (e.g., Image 6).

6

Close in, white eight-armed octocoral polyps and a cream lobed soft coral grew beside a brown massive colony on rock crusted with red and purple coralline algae (e.g., Image 8).

8

Coral cover

• Reference: Khaled bin Sultan Living Oceans Foundation, Global Reef Expedition (in situ transect)
• The expedition's in situ point-count transects at this station recorded 35% live coral cover against 20% total algal cover.
• Transect mean 35 ± 3.2% SE (n = 6 transects; Living Oceans Foundation per-transect benthic data); the headline above is the expedition's station value (the headline weights each depth equally; one depth had a single transect).

Stressors

Anderson recorded COTS damage from multiple colonies at 14 m, even as much of the surrounding reef stayed lush. Sickly and dying Seriatopora hystrix also turned up on several transects, alongside, not in place of, the COTS activity (e.g., Image 2).

2

One hazy shallow frame shows broad fields of dead, algal-filmed branching skeleton and rubble, with live corymbose and branching colonies persisting as islands within it; the photograph itself cannot assign a cause to that mortality (e.g., Image 3).

3

Fish and other fauna

Two huge Malabar groupers made an appearance.

Comparisons with other data

No other surveys have been conducted at this site to date. Within 5 km, three XL Catlin Seaview Survey stations recorded 16–32% hard coral cover between 2012 and 2016; the nearest, XL Catlin Seaview Survey at transect 15022, 2.75 km away, read 17–32% between 2012 and 2016.

Other notes

Reef name: Anderson's sheet logs this station as AU166151 on 'Unnamed Reef 166' (his field notes head the dive 'Unnamed Reef Leisure Cat dive 3 (AU166151)'); the station code AU74151 and his sheet's two earlier stations that day (AU74147, AU74149) use Unnamed Reef 74, and the field report's final schedule lists UN Reef (13-116) for 29 September 2014. The pin keeps its station code. The page leads with Unnamed Reef 74: the station lies 179 m from AU74147, which his notes place on Unnamed Reef 74, and the expedition's station table codes it AU74151; his sheet's code for it is AU166151 ('Unnamed Reef 166').