Deep-sea coral distribution on seamounts, oceanic islands, and continental slopes in the Northeast Atlantic

Abstract

A database of deep-water (> 200 m) antipatharians, scleractinians, and gorgonians has been assembled for the NE Atlantic to determine what their distribution and diversity was before coral habitats became heavily impacted by bottom fishing gear. Benthic sampling expeditions from 1868–1985 have provided 2547 records showing the deepwater distribution of 22 species of antipatharians, 68 species of scleractinians, and 83 species of gorgonians with the majority of records found from seamounts, oceanic islands, and the continental slope of the warm temperate region. Too little is known about the coral biota of boreal and tropical seamounts to assess their levels of endemism, but on seamounts in the warm temperate region of the NE Atlantic the level endemism in antipatharian, scleractinian and gorgonian corals is low (< 3%). Many of the species found on seamounts are characteristic of oceanic islands in this region and the oceanic islands have a significantly different coral fauna to that recorded at the same depths on the continental slope. Given the key role that corals can play in structuring deep-sea habitats it is hoped that our database will help inform the development of a network of marine protected areas to provide long-term protection for the differing communities found on continental slopes and isolated offshore habitats.