It may not be as warm or accessible as the Great Barrier Reef, but Ireland's deep seabed is home to some of the most spectacular coral yet seen by a group of European scientists.
The "profusion of life", including new combinations of marine animals, was identified by a Franco-Irish research expedition that presented its findings in the Shannon estuary port of Foynes yesterday.
Photographic images of the coral on the Porcupine Bank, Porcupine Seabight and Rockall bank off the west coast were captured by the team, using a remotely operated vehicle (ROV), Victor.
The four-ton Victor was provided for the expedition by IFREMER, the French marine research institute. Its flagship, the L'Atalante, was host vessel for the two-week voyage, co-funded by the Marine Institute here.
Chief scientist on board was Dr Karine Olu from IFREMER, working with Dr Anthony Grehan of NUI, Galway's Martin Ryan Institute, Dr Andy Wheeler of University College Cork, and researchers from Belgium, Holland and Germany.
The L'Atalante left Cork on July 31st and benefited from good weather for most of the trip. The Victor made 10 dives at depths of up to 1,000 metres, and the scientists and ship's pilots worked three watches over 24hour periods to make the most of the information collected on the seafloor.
The surveys revealed an underwater "wonder world" of coral gardens "teeming with life", according to the team. To date, scientists believed coral existed only on the summits of carbonate mounds - which are in turn associated with mineral reserves in some areas. However, this survey found living coral on the mounds and on the seafloor close by.
In what Dr Wheeler described yesterday as a "bizarre interaction between biology and geology", the evidence showed the mounds were eroded by strong currents, but new growth then colonised the area. Dr Grehan noted there was very little evidence of damage to the corals - although man's mark on the environment was recorded when a plastic cup was photographed at 300 metres.
The coral ecosystems are a significant habitat for juvenile fish, which flourish in this environment. Indicators of extensive coral presence, including a major new development extending for 40 nautical miles west of Rockall, were confirmed recently by the National Seabed Survey, which is being undertaken by the Geological Survey of Ireland in association with the Marine Institute. This Franco-Irish trip presented the first opportunity to study the habitat in close detail.
The scientists were reluctant to be drawn on any conclusive link with mineral reserves. Carbonate mounds have been linked to cold seepages of gas in other areas, but there was no biological indicator of gas escape on the mounds studied on this trip.
"We cannot say that there was not gas seepage in the past," Dr Miriam Sibuet, head of IFREMER's deep-sea environment department, said yesterday.
Dr Grehan said the pristine state of the environment was heartening. It would allow key Irish agencies to develop and implement management strategies to ensure the long-term conservation of the deep-water ecosystem.
A further survey by Irish geologists is to be conducted shortly on a sister IFREMER research vessel.
