Deep-water Coral - Discovery and Study

Discovery and Study

Deep-water corals are enigmatic because they construct their reefs in deep, dark, cool waters at high latitudes, such as Norway's Continental Shelf. They were first discovered by fishermen about 250 years ago, which garnered interest from scientists. Early scientists were unsure how the reefs sustained life in the seemingly barren and dark conditions of the northerly latitudes. It was not until modern times, when manned mini-submarines first reached sufficient depth, that scientists began to understand these organisms. Pioneering work by Wilson (1979) shed light on a colony on the Porcupine Bank, off Ireland. The first ever live video of a large deep-water coral reef was obtained in July, 1982, when Statoil surveyed a 15 metres (49 ft) tall and 50 metres (160 ft) wide reef perched at 280 metres (920 ft) water depth near Fugløy Island, north of the Polar Circle, off northern Norway.

During their survey of the Fugløy reef, Hovland and Mortensen also found seabed pockmark craters near the reef. Since then, hundreds of large deep-water coral reefs have been mapped and studied. About 60 percent of the reefs occur next to or inside seabed pockmarks. Because these craters are formed by the expulsion of liquids and gases (including methane), several scientists hypothesize that there may be a link between the existence of the deep-water coral reefs and nutrients seepage (light hydrocarbons, such as methane, ethane, and propane) through the seafloor. This hypothesis is called the 'hydraulic theory' for deep-water coral reefs.

Lophelia communities support diverse marine life, such as sponges, polychaete worms, mollusks, crustaceans, brittle stars, starfish, sea urchins, bryozoans, sea spiders, fish and many other vertebrate and invertebrate species.

The first international symposium for deep-water corals took place in Halifax, Canada in 2000. The symposium considered all aspects of deep-water corals, including protection methods.

In June 2009, Living Oceans Society led the Finding Coral Expedition on Canada’s Pacific coast in search of deep sea corals. Using one person submarines, a team of international scientists made 30 dives to depths of over 500 meters and saw giant coral forests, darting schools of fish, and a seafloor carpeted in brittle stars. During expedition, scientists identified 16 species of corals. This research trip was the culmination of five years of work to secure protection from the Canadian Government for these slow-growing and long-lived animals, which provide critical habitat for fish and other marine creatures.