Cold-Water Coral Reefs

Cold-water corals build reefs that are among the most unique and vulnerable ecosystems in the deep sea. Their significance is highlighted by several key factors: (i) they serve as biodiversity hotspots, supporting over 4,000 species in the North Atlantic alone—more than three times the number found on and within the surrounding seafloor; (ii) they are globally distributed, occurring along nearly all continental margins; and (iii) over geological timescales, they can form large elevated structures on the seafloor, known as coral mounds, which provide high-resolution paleorecords of reef development and ecosystem response, but also sequester significant but as yet poorly constrained quantities of carbon(ate).

Cold-water corals are today threatened by fishing, oil and gas exploration as well as increasing marine pollution, and they are expected to be severely affected by climate-driven changes such as ocean warming, oxygen depletion and acidification. However, their sensitivity to these stressors remains insufficiently understood and are the focus of ongoing research.