Summary Estimated observations of the biotope AA.J3L3 were collected from the Baltic Sea area by expert judgements for HELCOM Red List of biotopes, habitats and biotope complexes. Description Baltic photic sand dominated by ocean quahog (Arctica islandica)The HELCOM Red List of Baltic Sea underwater biotopes, habitats and biotope complexes (2013) is an updated and improved version of the Red List assessment of marine and coastal biotopes and biotope complexes published in 1998. The classification of the report follows the proposed International Union for Conservation of Nature (IUCN) criteria and assessment principals but with some modifications for the Baltic Sea.Altogether, the HELCOM Underwater Biotop e and habitat classification (HELCOM HUB) includes 209 biotopes of which 59 were red-listed. Many of the red-listed biotopes are located in deep areas of the Baltic Sea due to oxygen-free nature as well as in the southwestern Baltic Sea due to the salinity restricted distribution of species in certain biotope. The HELCOM assessment relies heavily on expert judgment and inference, and the questionnaire data represents the estimated presence-absence data not in-situ measured data. This must be taken in account when observing the map presentation. The biotopes are shown on the map using the EEA 100 km grid. This dataset displays estimated presence of AA.J3L3 according to HELCOM RED LIST assessment experts:The main distribution area of this biotope is the western Baltic Sea. The largest populations of A. islandica are found in Kiel and Mecklenburg Bights (Zettler et al. 2001). The distribution map indicates the area in the 100 x 100 km grid where biotope is known to occur.(Data (expert judgements) collected in HELCOM RED LIST project, released in May 2013)

Summary Estimated observations of the biotope AB.A1F1 and AB.M1F1 were collected from the Baltic Sea area by expert judgements for HELCOM Red List of biotopes, habitats and biotope complexes. Description Baltic aphotic rock and boulders or mixed hard and soft substrates dominated by sea squirts (Ascidiacea)The HELCOM Red List of Baltic Sea underwater biotopes, habitats and biotope complexes (2013) is an updated and improved version of the Red List assessment of marine and coastal biotopes and biotope complexes published in 1998. The classification of the report follows the proposed International Union for Conservation of Nature (IUCN) criteria and assessment principals but with some modifications for the Baltic Sea.Altogether, the HELCOM Underwater Biotope and habitat classification (HELCOM HUB) includes 209 biotopes of which 59 were red-listed. Many of the red-listed biotopes are located in deep areas of the Baltic Sea due to oxygen-free nature as well as in the southwestern Baltic Sea due to the salinity restricted distribution of species in certain biotope. The HELCOM assessment relies heavily on expert judgment and inference, and the questionnaire data represents the estimated presence-absence data not in-situ measured data. This must be taken in account when observing the map presentation. The biotopes are shown on the map using the EEA 100 km grid. This dataset displays estimated presence of AB.A1F1 and AB.M1F1 according to HELCOM RED LIST assessment experts:The biotopes occur in the Kattegat and the Belt Sea. The distribution map indicates the area in the 100 x 100 km grid where biotopes are estimated to occur based on environmental gradients and the availability of the specific substrates.(Data (expert judgements) collected in HELCOM RED LIST project, released in May 2013)

Summary Estimated observations of the biotope AB.H2T1 were collected from the Baltic Sea area by expert judgements for HELCOM Red List of biotopes, habitats and biotope complexes. Description Baltic aphotic muddy sediment characterized by sea-pensThe HELCOM Red List of Baltic Sea underwater biotopes, habitats and biotope complexes (2013) is an updated and improved version of the Red List assessment of marine and coastal biotopes and biotope complexes published in 1998. The classification of the report follows the proposed International Union for Conservation of Nature (IUCN) criteria and assessment principals but with some modifications for the Baltic Sea.Altogether, the HELCOM Underwater Biotope and habitat classification (HELCOM HUB) includes 209 biotopes of which 59 were red-listed. Many of the red-listed biotopes are located in deep areas of the Baltic Sea due to oxygen-free nature as well as in the southwestern Baltic Sea due to the salinity restricted distribution of species in certain biotope. The HELCOM assessment relies heavily on expert judgment and inference, and the questionnaire data represents the estimated presence-absence data not in-situ measured data. This must be taken in account when observing the map presentation. The biotopes are shown on the map using the EEA 100 km grid. This dataset displays estimated presence of AB.H2T1 according to HELCOM RED LIST assessment experts:Because of its salinity and depth requirements, this habitat occurs mostly in the deeper parts of Kattegat. The most common sea pen species Virgularia mirabilis and Pennatula phosphorea have been observed for example in the deep trenches of the Kattegat (The Kattegat trench, the Ddupa Rännan trench), in the Groves Flak and near the island Ven in the Sound. The habitat has likely suffered from bottom trawling as trawling marks and badly disturbed seabeds has been recorded in the area of their distribution. Distribution map indicates the area in the 100 x 100 km grid where biotopes are known to occur.(Data (expert judgements) collected in HELCOM RED LIST project, released in May 2013)

Summary Estimated observations of the biotope AA.I3L10, AA.J3L10, AB.I3L10 and AB.J3L10 were collected from the Baltic Sea area by expert judgements for HELCOM Red List of biotopes, habitats and biotope complexes. Description Baltic photic or aphotic coarse sediment or sand dominated by multiple infaunal bivalve species: Macoma calcarea, Mya truncata, Astarte spp., Spisula spp. The HELCOM Red List of Baltic Sea underwater biotopes, habitats and biotope complexes (2013) is an updated and improved version of the Red List assessment of marine and coastal biotopes and biotope complexes published in 1998. The classification of the report follows the proposed International Union for Conservation of Nature (IUCN) criteria and assessment principals but with some modifications for the Baltic Sea.Altogether, the HELCOM Underwater Biotope and habitat classification (HELCOM HUB) includes 209 biotopes of which 59 were red-listed. Many of the red-listed biotopes are located in deep areas of the Baltic Sea due to oxygen-free nature as well as in the southwestern Baltic Sea due to the salinity restricted distribution of species in certain biotope. The HELCOM assessment relies heavily on expert judgment and inference, and the questionnaire data represents the estimated presence-absence data not in-situ measured data. This must be taken in account when observing the map presentation. The biotopes are shown on the map using the EEA 100 km grid. This dataset displays estimated presence of AA.I3L10, AA.J3L10, AB.I3L10 andAB.J3L10according to HELCOM RED LIST assessment experts:Kiel bight to Isle of Fehmarn, might occasionally occur in Mecklenburg Bight to Darss sill, South-westernBaltic Sea. The distribution map indicates the area in the 100 x 100 km grid where biotope is known tooccur.AA.I3L10, AA.J3L10, AB.I3L10 andAB.J3L10have been placed in the Red List classification to the category of Near Threatened (NT) biotopes. (Data (expert judgements) collected in HELCOM RED LIST project, released in May 2013)

Summary Estimated observations of the biotope AB.A1G3 and AB.M1G3 were collected from the Baltic Sea area by expert judgements for HELCOM Red List of biotopes, habitats and biotope complexes. Description Baltic aphotic rock and boulders or mixed hard and soft substrates dominated by stone corals (Scleractinida)The HELCOM Red List of Baltic Sea underwater biotopes, habitats and biotope complexes (2013) is an updated and improved version of the Red List assessment of marine and coastal biotopes and biotope complexes published in 1998. The classification of the report follows the proposed International Union for Conservation of Nature (IUCN) criteria and assessment principals but with some modifications for the Baltic Sea.Altogether, the HELCOM Underwater Biotope and habitat classification (HELCOM HUB) includes 209 biotopes of which 59 were red-listed. Many of the red-listed biotopes are located in deep areas of the Baltic Sea due to oxygen-free nature as well as in the southwestern Baltic Sea due to the salinity restricted distribution of species in certain biotope. The HELCOM assessment relies heavily on expert judgment and inference, and the questionnaire data represents the estimated presence-absence data not in-situ measured data. This must be taken in account when observing the map presentation. The biotopes are shown on the map using the EEA 100 km grid. This dataset displays estimated presence of AB.A1G3and AB.M1G3according to HELCOM RED LIST assessment experts:The biotopes are restricted to the north Kattegat, where environmental conditions are nearly fully marine. The distribution map indicates the area in the 100 x 100 km grid where biotopes are known to occur. OCEANA (2013) encountered Carophylla smithii along the Swedish coast.(Data (expert judgements) collected in HELCOM RED LIST project, released in May 2013)

Summary Estimated observations of the biotope 1620 were collected from the Baltic Sea area by expert judgements for HELCOM Red List of biotopes, habitats and biotope complexes. Description Boreal Baltic islets and small islandsThe HELCOM Red List of Baltic Sea underwater biotopes, habitats and biotope complexes (2013) is an updated and improved version of the Red List assessment of marine and coastal biotopes and biotope complexes published in 1998. The classification of the report follows the proposed International Union for Conservation of Nature (IUCN) criteria and assessment principals but with some modifications for the Baltic Sea.Altogether, the HELCOM Underwater Biotope and habitat classification (HELCOM HUB) includes 209 biotopes of which 59 were red-listed. Many of the red-listed biotopes are located in deep areas of the Baltic Sea due to oxygen-free nature as well as in the southwestern Baltic Sea due to the salinity restricted distribution of species in certain biotope. The HELCOM assessment relies heavily on expert judgment and inference, and the questionnaire data represents the estimated presence-absence data not in-situ measured data. This must be taken in account when observing the map presentation. The biotopes are shown on the map using the EEA 100 km grid. This dataset displays estimated presence of the biotope 1620 according to HELCOM RED LIST assessment experts:The distribution map indicates the area in the 100 x 100 km grid where biotope is known to occur (Naturvårdverket 2011).(Data (expert judgements) collected in HELCOM RED LIST project, released in May 2013)

Summary Estimated observations of the biotope AB.H4U1 were collected from the Baltic Sea area by expert judgements for HELCOM Red List of biotopes, habitats and biotope complexes. Description Baltic aphotic muddy sediment dominated by meiofaunaThe HELCOM Red List of Baltic Sea underwater biotopes, habitats and biotope complexes (2013) is an updated and improved version of the Red List assessment of marine and coastal biotopes and biotope complexes published in 1998. The classification of the report follows the proposed International Union for Conservation of Nature (IUCN) criteria and assessment principals but with some modifications for the Baltic Sea.Altogether, the HELCOM Underwater Biotope and habitat classification (HELCOM HUB) includes 209 biotopes of which 59 were red-listed. Many of the red-listed biotopes are located in deep areas of the Baltic Sea due to oxygen-free nature as well as in the southwestern Baltic Sea due to the salinity restricted distribution of species in certain biotope. The HELCOM assessment relies heavily on expert judgment and inference, and the questionnaire data represents the estimated presence-absence data not in-situ measured data. This must be taken in account when observing the map presentation. The biotopes are shown on the map using the EEA 100 km grid. This dataset displays estimated presence of AB.H4U1 according to HELCOM RED LIST assessment experts:The biotope is assumed to occur throughout the Baltic Sea both in shallow coastal waters and in the deeper central parts of the sea. The distribution map indicates the area in the 100 x 100 km grid where biotope is reported to occur. The biotope may have a significantly wider distribution.(Data (expert judgements) collected in HELCOM RED LIST project, released in May 2013)

Summary Estimated observations of the biotope 1160 were collected from the Baltic Sea area by expert judgements for HELCOM Red List of biotopes, habitats and biotope complexes. Description Large shallow inlets and baysThe HELCOM Red List of Baltic Sea underwater biotopes, habitats and biotope complexes (2013) is an updated and improved version of the Red List assessment of marine and coastal biotopes and biotope complexes published in 1998. The classification of the report follows the proposed International Union for Conservation of Nature (IUCN) criteria and assessment principals but with some modifications for the Baltic Sea.Altogether, the HELCOM Underwater Biotope and habitat classification (HELCOM HUB) includes 209 biotopes of which 59 were red-listed. Many of the red-listed biotopes are located in deep areas of the Baltic Sea due to oxygen-free nature as well as in the southwestern Baltic Sea due to the salinity restricted distribution of species in certain biotope. The HELCOM assessment relies heavily on expert judgment and inference, and the questionnaire data represents the estimated presence-absence data not in-situ measured data. This must be taken in account when observing the map presentation. The biotopes are shown on the map using the EEA 100 km grid. This dataset displays estimated presence of the biotope 1160 according to HELCOM RED LIST assessment experts:Large shallow inlets and bays occur in all HELCOM sub-regions of the Baltic Sea area. The distribution map indicates the area in the 100x100 km grid where biotope is known to occur (Naturvårdverket 2011, EUNIS Database).(Data (expert judgements) collected in HELCOM RED LIST project, released in May 2013)

Summary Estimated observations of the biotope AE.O5 were collected from the Baltic Sea area by expert judgements for HELCOM Red List of biotopes, habitats and biotope complexes. Description Baltic Sea aphotic pelagic below halocline oxicThe HELCOM Red List of Baltic Sea underwater biotopes, habitats and biotope complexes (2013) is an updated and improved version of the Red List assessment of marine and coastal biotopes and biotope complexes published in 1998. The classification of the report follows the proposed International Union for Conservation of Nature (IUCN) criteria and assessment principals but with some modifications for the Baltic Sea.Altogether, the HELCOM Underwater Biotope and habitat classification (HELCOM HUB) includes 209 biotopes of which 59 were red-listed. Many of the red-listed biotopes are located in deep areas of the Baltic Sea due to oxygen-free nature as well as in the southwestern Baltic Sea due to the salinity restricted distribution of species in certain biotope. The HELCOM assessment relies heavily on expert judgment and inference, and the questionnaire data represents the estimated presence-absence data not in-situ measured data. This must be taken in account when observing the map presentation. The biotopes are shown on the map using the EEA 100 km grid. This dataset displays estimated presence of AE.O5 according to HELCOM RED LIST assessment experts:The distribution map indicates the area in the 100 x 100 km grid where biotope is known to occur. The habitat only makes up a section of the pelagic water mass in the area indicated by the map. The map is created based on the bathymetric data of the Baltic Proper. According to the depth contours, the grid indicated on the map include areas deeper than 60-80m.(Data (expert judgements) collected in HELCOM RED LIST project, released in May 2013)

Summary Estimated observations of the biotope AB.B1E4 were collected from the Baltic Sea area by expert judgements for HELCOM Red List of biotopes, habitats and biotope complexes. Description Baltic aphotic hard clay dominated by Astarte spp.The HELCOM Red List of Baltic Sea underwater biotopes, habitats and biotope complexes (2013) is an updated and improved version of the Red List assessment of marine and coastal biotopes and biotope complexes published in 1998. The classification of the report follows the proposed International Union for Conservation of Nature (IUCN) criteria and assessment principals but with some modifications for the Baltic Sea.Altogether, the HELCOM Underwater Biotope and habitat classification (HELCOM HUB) includes 209 biotopes of which 59 were red-listed. Many of the red-listed biotopes are located in deep areas of the Baltic Sea due to oxygen-free nature as well as in the southwestern Baltic Sea due to the salinity restricted distribution of species in certain biotope. The HELCOM assessment relies heavily on expert judgment and inference, and the questionnaire data represents the estimated presence-absence data not in-situ measured data. This must be taken in account when observing the map presentation. The biotopes are shown on the map using the EEA 100 km grid. This dataset displays estimated presence of AB.B1E4 according to HELCOM RED LIST assessment experts:Known from German and Polish waters in the Baltic Sea. Aphotic hard clay dominated by Astarte spp. occurs on the sills (thresholds) of the Slupsk Furrow that connects the Bornholm Deep with the Gotland Deep and Gdansk Deep. Distribution map indicates the area in the 100 x 100 km grid where biotope is known to occur.(Data (expert judgements) collected in HELCOM RED LIST project, released in May 2013)