Black coral

Photo: Neil DeMaster · CC BY-NC

Black coral trees at Gladden Wall grow on the shaded vertical face below 20 metres, some colonies reaching 2 metres in height and estimated to be centuries old. Despite the name the living polyps are white or cream; the black colour is the skeleton revealed only when the animal dies or is harvested. They provide critical structural habitat for arrow crabs, wire coral gobies, and longnose hawkfish perched on branch tips.