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The report provides a description of the ecosystem in the Central Arctic Ocean, or CAO. This is a deep-sea area with two main basins of depths to 4–5 km, separated by the Lomonosov Ridge. The CAO is a globally unique ecosystem, characterized by presence of sea ice and very low primary production by phytoplankton and ice algae. Atlantic water flows into the CAO through the deep Fram Strait and across the Barents Sea shelf, and continues as a set of boundary currents anti-clockwise around the slopes of the CAO basins. The circulation of the boundary currents takes place at an intermediate depth of about 200–1000 m, underneath a gradient layer with strong salinity and density stratification, and a seasonally dynamic top layer with two prominent circulation features: the Beaufort Gyre in Canada Basin, and the Transpolar Drift across the North Pole that exits in Fram Strait. A smaller amount of Pacific water (ratio of about 1:5 to Atlantic water) flows north through the Chukchi Sea and into the gradient layer between the surface polar water and the deeper Atlantic water of the boundary currents. The Pacific water exits primarily through Canadian Arctic Archipelago passages into Baffin Bay. The circulating waters and floating sea ice form the dynamic habitats of the animals and plants that constitute the living part of the CAO ecosystem. Large calanoid copepods, with Calanus hyperboreus as the most important species in terms of zooplankton biomass, reproduce successfully mainly in the peripheral parts of the CAO with seasonal ice cover. Sea ice amphipods, with Gammarus wilkitzkii and Apherusa glacialis as the two most prominent species, are the dominant group among the sea ice invertebrate fauna. An important issue addressed in the report, is how the ice fauna can maintain their populations by recolonizing new sea ice as it forms in autumn and winter. About 50 species of fish have been either found (39 species), or are considered likely to occur (14 species), in the CAO. Most of them are small species, dominated by eelpouts along the basin slopes, and sculpins on the upper slopes and surrounding shelves. Two small cods, polar cod (Boreogadus saida) and Arctic cod (Arctogadus glacialis), are assumed to be the most important fishes in the CAO foodwebs. Thirty-five species of birds and 35 species of marine mammals have been recorded in the CAO. Most of them are seasonal visitors, and the CAO plays small roles for their populations overall. Exceptions to this are two species of gulls, ivory gull (Pagophila eburnea) and Ross’s gull (Rhodostethia rosea), for which the marginal ice zone of the CAO in late summer provides a habitat for large parts of their global populations. Polar bear (Ursus maritimus) is the marine mammal with strongest dependence on sea ice habitats in the CAO. Considerable parts of several subpopulations of polar bear (Barents Sea, Laptev Sea, Chukchi Sea, Southern and Northern Beaufort Sea subpopulations) move seasonally with the retreating sea ice into the CAO in summer. There has been a large loss in sea ice since the 1990s in what is termed the “Great melt”, with a pronounced change from heavier multiyear pack ice to thinner annual ice. The report describes some of the associated changes in the CAO ecosystem associated with the loss and change in sea ice habitats. However, the main aim of this report is to provide detailed descriptions of the current CAO ecosystem and its various components, thereby providing a basis for more in-depth assessments on the impacts of climate change and other human activities in future. Changes carried out on 18/08/2022: PICES and PAME logos added, and information added to the disclaimer.

Andfjorden marine verneområde er et stort område som strekker seg fra fjord til hav. Området har en variert topografi som gir levested for en stor variasjon av marine arter. Her finnes rekefelt og gyteområder for torsk, kveite, uer og rognkjeks. En rekke naturtyper er kartlagt i området slik som skjellsand, tareskog og ruglbunn. Sårbare naturtyper som korallrev, bambuskorallskog, hardbunnskorallskog, svampskog og sjøfjærbunn er observert gjennom Mareano undersøkelser og av fiskere i Andfjorden. For første gang er biotop-modellering brukt som redskap for å predikere forekomsten av hardbunnskoraller, bløtbunnskoraller og svampskog i et marint verneområde på norskekysten.

In 1999, the Norwegian fisheries authorities established a regulation for the protection of cold-water coral reefs, Lophelia pertusa, against damage from bottom trawling, including: prohibition of intentional destruction, precaution when fishing in the vicinity of known sites and, for certain locations, a total ban of bottom trawling. As of today, there are nine areas that have received a species protection and where bottom trawling is banned: Sula, Iverryggen, Røst, Tisler, Fjellknausene, Korallen, Træna, Breisunddjupet and Rauerfjorden (for geographical coordinates see Appendix 2). The present report is a response to a request from the Directorate of Fisheries to “evaluate areas for protection of coral reefs”. The request included three tasks: 1) Describe the distribution of reefs near by the protected sites on the background of new knowledge. The directorate will use the information to consider whether or not the present borders of the protected areas are appropriate. 2) Evaluate whether the nine specific sites are representative for the reefs along the coast and offshore. 3) Consider whether new sites can add to the total representativeness of protected reefs along the coast and offshore. In this report the representativity of larger known Lophelia sites has been evaluated based on a combination of growth form and geographical location. The aim was to create a network of protected coral areas that covers most of the different reef forms in each to four defined sub-coral provinces and seascapes along the Norwegian coastline. The reef forms are (example site): 1) elongated or cigar-like (Træna), 2) drop-like to elongated, with or without signs of sea-bed erosion at the reef front facing the current (Breisunddjupet, Hola), 3) reef-complexes consisting of hundreds or thousands of coral domes growing close to each other or merged together (Sula), 4) single and circular of up to 50 m in height (Fugløya), 5) wall-reefs consist of colonies growing on steep walls or on overhangs in fjords (Straumsneset), 6) hillreefs grow in sloping terrain on the coast and in fjords, for example on sills of fjords (Stjernsund). A last category (7) refers to their function: connectivity or bridgehead that function as links between reefs in the Atlantic ocean and the Norwegian coast through the transport of larvae (Storneset). In addition we divided the Norwegian sea areas into three seascapes: 1) coast and the fjords, 2) continental shelf, 3) shelf brake including the slope. The Norwegian coast boarders three seas: the North Sea with Skagerrak, the Norwegian Sea and the Barents Sea. Although these regions are all influenced by the North-East Atlantic water, they have distinctive physical conditions that will, for instance, influence the connectivity between Lophelia in Norwegian waters and the reefs further south-west in the Atlantic ocean. Our hypothesis is that higher exposure of an area to the inflow of Atlantic water, the higher the connectivity among reefs in the Atlantic Ocean and Norwegian waters. This hypothesis and the general hydrographical situation are the basis for an identification of four Coral Subprovinces along the Norwegian coast and shelf: Skagerrak, Vestlandet, Midt-Norge and Nord-Norge. Within these sub-provinces, we suggest new sites that will add to the representativeness of protected reefs. We also suggest to close at least one site in each of the Coral Sub-provinces, against all fishing activities including long-line and gill-net fishing. Once the fishing impact is removed, it will allow the study of other impact factors, such as climate change and ocean acidification, which in turn will make it easier to interpret the results of reef monitoring in the future.