Occurrences of Lophelia pertusa on the Atlantic margin

While corals are most abundant and species-rich in shallow-water tropical seas, it has been
known for many years that scleractinian corals are also found in temperate regions where
there can be large structures of coral in deep continental shelf edge waters. These
accumulations, variously referred to as patches, coral banks, bioherms and reefs, are
composed of several coral species but the most abundant is Lophelia pertusa (L.) (Fig 1).
This coral’s growth form provides a habitat for a diverse associated fauna. L. pertusa does
not contain symbiotic algae (zooxanthellae) and so unlike tropical coral species is not
restricted to well-lit surface waters. Since individual polyps divide and grow to form
colonies, but adult polyps are no longer joined by a tissue connection they are correctly
termed pseudo-colonial azooxanthellate corals. There is growing concern over the
environmental sensitivity of deep-water coral communities to both hydrocarbon exploration
and deep-water trawling (Roberts, 1997; Rogers, 1999).