Deep-sea corals: out of sight, but no longer out of mind

Two-thirds of all known coral species live in waters that are deep, dark, and cold. Yet due to the difficulty of researching them in their natural environment, their biology and ecology are poorly understood. Deep-sea coral communities provide habitat for many vertebrate and invertebrate species, including some commercially important fish and crustacean populations. Some have levels of biological diversity comparable to shallow-water reefs. They are also highly susceptible to disturbance from many of our deep-sea activities. Bottom trawling in particular has caused considerable destruction of these communities around the world. Due to their extreme longevity and slow growth, recovery is likely to be in the order of decades or even centuries. We provide an overview of deepwater coral biology and ecology, identify the more manageable threats, and suggest recommendations to mitigate further loss.