We've known about them for over a century. Last year their full extent was recorded in the international scientific journal Nature, and by this newspaper. Yet most of us still associate coral reefs with exotic, warm tropical locations.
Not so. Our western waters are replete with them, and they are as close as 100 kilometres to the coast. Why aren't we hearing more about it? Perhaps it is because of their link with oil and gas exploration.
As Dr Mark Costello, an ecological consultant, outlines in the current issue of Technology Ire- land, the occurrence of deepwater coral and seepage of methane and other gases from hydrocarbon reservoirs beneath the seabed may be more than a coincidence.
The coral may, therefore, indicate the presence of these mineral reserves. Greenpeace sought unsuccessfully to prevent oil and gas exploration near coral reefs in British waters, arguing that it would breach the EU Habitats Directive.
The relationship between the coral and the methane seeps is still the subject of debate, he says, but exploration work by the oil and gas industry is stimulating interest in scientific research. These Lophelia reefs contain a biodiversity that is as rich as those in the tropics.
Over 860 species of animals have been recorded on Lophelia in the north-east Atlantic, and about 300 on single reefs off Norway, Shetland and the Bay of Biscay.
Redfish, saithe, cod, ling, tusk, squat lobsters and other shellfish weave among the coral's branches, and a wide variety of animals, including sponges, depend on it for life.
The reefs are formed by two coral species which interconnect with tubes of a worm called eu-nice norvegicus but their existence in these waters is not widely realised, he says, because of lack of offshore ecological research.
In spite of the deepwater location, the coral can grow at rates similar to those in the tropics, he says. Norwegian studies indicate a growth rate of six millimetres annually, which means that reefs of one or two metres can be several hundred years old.
Unfortunately, damage by bottom-trawling has rendered rubble of some reefs off Norway and Shetland, and the unique habitat will take centuries to recover.