Cold water corals get a visit

Polarstern and JAGO in action in front of Norway's coast

Research vessel Polarstern in action off Lofoten. © Jürgen Schauer / IFM-GEOMAR
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The largest known cold-water coral reef south of the Norwegian Lofoten Islands was again visited by the German research icebreaker Polarstern. About 350 meters below the sea surface, the scientists use the submersible JAGO to investigate the geological structures beneath the roasting reef.

The cold-water coral reefs discovered a few years ago stretch as a broad band along the north-western European continental margin. The deep reefs off northern Norway are the most northerly occurrences of cold-water corals to date and were formed only after the last ice age.

They have a high biodiversity, are inhabited by numerous fish species and are now protected regionally, so that they are not destroyed by the trawl fishery. Reef-forming cold-water corals live at depths between 60 and 2, 000 meters and prefer flow-exposed elevations. They feed mainly on zooplankton, which is abundant in the cold nutrient-rich waters of the North Atlantic. In contrast to the tropical hot water corals, they do not harbor any algae in their tissue, which produce nutrients with the help of sunlight and pass them on to the coral.

Cold water corals of the species Lophelia pertusa and colorful gorgonians at 310 m depth at the Röst reef south of the Norwegian Lofoten. © Jürgen Schauer / IFM-GEOMAR

"The fragile reefs can be very well documented and sampled with the necessary accuracy and care by a research dive boat equipped for scientific work, " Dr. Michael Klages from the Alfred Wegener Institute for Polar and Marine Research, who, together with his colleagues from the Jacobs University in Bremen, manages important parts of the EU project HERMES. HERMES is dedicated to the study of rich and largely unknown ecosystems along European continental margins from the North Atlantic to the Mediterranean.

The JAGO team with logistics expert Karen Hissmann and pilot Jürgen Schauer from the IFM-GEOMAR proudly refers to the impeccable functioning of their submersible, which has already been able to head for many exotic destinations during its one thousand dives. Prof. Dr. Jörn Thiede, director of the Alfred Wegener Institute and currently expedition leader on Polarstern praises the good teamwork with JAGO. "If German marine research institutes successfully use their modern instrumentation in joint projects, we will achieve world-wide sensational scientific excellence". display

(Alfred Wegener Institute, 20.06.2007 - AHE)