Rare cold water corals have been discovered off the coast of Mauritania around 60 km west off Cape Tamirist.
The living coral wall was discovered by the research ship the ‘Maria S. Merian’ on the continental shelf off the coast of Mauritania.
The flourishing reef was found by a diving robot at a depth of 615m and measures 50 to 60 m high and is 190 km long.
Professor André Freiwald, head of the Senckenberg am Meer Marine Research Department in Wilhelmshaven, Germany already suspected that he might find a cold water coral bank on the basis of previous research.
He was amazed at the extent though of the coral and reported heavily calcified Lophelia coral with orange-red polyps and gorgonias, which, beside the reef-building stony corals, form coral ecosystems known as octocoral gardens.
According to the excited expedition report, giant clams also hang on the coral galleries, in exactly the same way as is found elsewhere in Norwegian reef systems.
In the middle of the enormous rock formation of the undersea canyon area, the scientists also stumbled across the powerful Carrier crab Paromola and the Giant deep sea oyster Neopycnodonte, which previously had never been observed so far south. These giant oysters form thick populations and have been described as Methuselahs among animals, with some individuals living for over 500 years..
Similar coral ecosystems were previously only known from regions of the sea located much further to the north, around Scandinavia and in the Irish Sea. Unlike their tropical relatives, cold water corals live at a cold 13C in the dark and nutrient-rich deep sea region below 200 m.
Prof. Freiwald was aware of a loose cold water coral reef which extends to southern regions. Until now, however, scientists had only found fossil coral reef structures on the seafloor off the coast of Gibraltar and Morocco.
Prof. Freiwald believes that one reason for the occurrence of the anthozoans so far south could be due to the offshore winds pushing the surface waters from the Mauritanian cliffs out into the open ocean and thereby permitting a following flow of cold and nutrient-rich water from the depths. This evidently not only ensures that the Mauritanian waters are among the richest of any in fish but also presumably also provides the cold water corals with appropriate feed.