N. GBR - Blue (AU4333)

Setting

The site sits in a Habitat Protection (Blue) Zone, where line fishing is permitted.

General benthic features

Two frames show gorgonians: a single large fan spread flat against the current beneath a cream lobed soft coral, and then a whole forest of red and pink sea fans standing in green, particle-laden water, silhouetted rather than lit (e.g., Image 3, Image 5).

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The two remaining frames are close over the substrate: crowded small mounding and knobby colonies, muted and silt-dusted, packed tight but low (e.g., Image 1, Image 2).

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Anderson noted plenty of coral structure below, but most of the coral had been replaced by algae or soft corals; soft corals, sponges, and sea fans now occupy much of it. Pockets of Stylophora, poritids, and fungids still held on among the soft-coral carpet. Porites was the most common coral genus on this station's transects (3.0% of the benthos), followed by Leptastrea (1.2%), Diploastrea (0.8%), and Cyphastrea, Montipora, and Turbinaria (0.7% each); bare substrate covered 18%, behind sediment-laden turf (40%), the largest non-coral class. Among the algal classes on this station's transects, sediment-laden turf (40%) led, followed by turf (17%) and macroalgae (7.3%).

Coral cover

• Reference: Khaled bin Sultan Living Oceans Foundation, Global Reef Expedition (in situ transect)
• The point-count survey read just 9.8% live coral, in cool, silty water, 23.5°C with 3-4 m of visibility.
• Transect mean 9.8 ± 0.8% SE (n = 6 transects; Living Oceans Foundation per-transect benthic data); the headline above is the expedition's station value.

Stressors

A fourth frame is tiered plating coral, concentric-ridged Pachyseris-type plates stacked down a ledge, with one plate stark white, either recently bleached or freshly dead with its ridges still crisp (e.g., Image 4).

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Fish and other fauna

Eight crown-of-thorns starfish were logged on the dive, along with a lionfish and plenty of other fish.

Comparisons with other data

No prior survey data from this site. If you would like to share yours, please email us.

Dive record

Anderson's second dive of 8 September 2014 was on this unnamed mid-shelf reef, in 3-4 m visibility with a fine layer of silt over everything.