| Summary: | Järnegren, J. & Kutti, T. 2014. Lophelia pertusa in Norwegian waters. What have we learned since 2008? – NINA Report 1028. 40 pp. This report was requested by the Norwegian Environment Agency as a platform of knowledge to evaluate Lophelia pertusa as a possible “selected nature type” (utvalgt naturtype). It is a literature review that summarizes available knowledge since 2008 on Lophelia pertusa biology, ecosystem structure and functioning. In addition, existing knowledge on the response of Lophelia to the effects of increased ocean temperature and acidification and expanding industrial activities are described. Lophelia pertusa (Linné, 1758) is a common stony coral, which forms extensive reefs in deep waters around the world. It has a wide range of tolerance, but is most abundant where bottom water temperatures range between 6-9°C, salinity is around 35, and with oxygen levels of 6.0- 6.2 ml/L. “High quality” coral sites, such as most of the Norwegian Lophelia habitats, are associated with bottom waters with Dissolved Inorganic Carbon (DIC) values <2170 µmol/kg and within a seawater density envelope of 27.35-27.65 kg/m3 . Lophelia does not contain photosynthetic symbionts but feeds on zooplankton, phytoplankton, bacteria and Dissolved Organic Material (DOM), depending on their availability. Most Norwegian Lophelia reefs seem to depend mainly on zooplankton for feed. The occurrence of Lophelia varies from scattered colonies or groups of colonies to vast reef complexes (such as the Røst and Sula reefs). Lophelia is distributed along most of the Norwegian coast, with the highest densities occurring on the continental shelf north of Stadt up to Lofoten and along the coasts and fjords of Møre og Romsdal and Trøndelag. Lophelia has a linear polyp extension rate of approximately 10 mm year-1 and the growth of a reef can amount to 5 mm year-1 . All reefs in Norwegian fjords and on the shelf have been formed after the retreat of the ice-sheet and the oldest reefs are around 8000 years. The Lophelia reefs are ...
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