The occurrence of the cold-water coral Desmophyllum pertusum (Lophelia pertusa) on oil and gas structures in the Norwegian sector of the North Sea

Abstract The occurrence of the cold-water coral Desmophyllum pertusum , also known as Lophelia pertusa , on oil and gas platforms in the North Sea was first reported in 1999. Since then, scientific literature has documented its occurrence on 22 oil platforms in the UK sector of the North Sea while there have been no reports form the Norwegian sector. This study presents records of D. pertusum from the Norwegian sector in in the North Sea, based on Equinor-operated installations. Reports and data from 28 installations were reviewed of which 22 documented presences of D. pertusum and six did not. The information analysed was not collected in a survey targeting D. pertusum and is thus not comprehensive. All platforms where D. pertusum have been identified, both in the UK and the Norwegian sectors, are in the northern part of the North Sea. Installations with coral occurrences in the Norwegian sector are generally situated in deeper water than the UK installations. The shallowest record of D. pertusum is at 60 m and the deepest at 335 m in the Norwegian sector as opposed to at 47 m and 153 m in the UK sector. The depth of the summer thermocline of the northern North Sea coincides well with the minimum depth of the corals.