The Great Barrier Reef (GBR) supports diverse, extensive mesophotic coral ecosystems (~30-100 m) along the edge of Australia’s continental shelf (Bridge et al. 2012). The first exploration of these deepwater reefs was conducted in the early 1980s using a small manned submersible, the Platypus, at Myrmidon Reef (Hopleyet al. 2007). On the eastern reef front, a thriving mesophotic coral community was discovered consisting of large, plating corals (Leptoseris, Pachyseris, and Montipora) and extremely high coral cover (Fig. 1a, b). Nearly 30 years later, we revisited the exposed front of Myrmidon Reef (18.2657°S, 147.4016°E) as part of the ‘‘Catlin Seaview Survey’’ (September 2012). Using a remotely operated vehicle, we surveyed an area of ~500 m2 between 50 and 65 m depth and observed extensive fields of plate-like rubble, overturned corals, and some living, recently broken-off coral fragments (e.g.,Pachyseris, Montipora, and Podabacia) (Fig. 1c, d). Given the signs of recent injury, the observed damage was likely caused by severe Tropical Cyclone Yasi, which passed ~100 km north of Myrmidon Reef in early February 2011, and was the only significant storm in this area since Cyclone Larry in 2006.

Depth range
50- 65 m

Mesophotic “mentions”
5 x (total of 330 words)

Classification
* Presents original data
* Focused on 'mesophotic' depth range
* Focused on 'mesophotic coral ecosystem'

Fields
Ecology
Long-term monitoring
Disturbances

Focusgroups
Scleractinia (Hard Corals)

Locations
Australia - Great Barrier Reef

Platforms
Remotely Operated Vehicle (ROV)