This dataset represents the integrated assessment of hazardous substances in the Baltic Sea in 2016-2021. This dataset displays the result of the assessment in HELCOM Assessment unit Level 3 (Division of the Baltic Sea into 17 sub-basins and further division into coastal and offshore areas).

This dataset represents the underlying data on core indicator Abundance of salmon spawners and smolt. The indicator evaluates the status of the abundance of salmon spawners and smolt in the Baltic Sea based on salmon smolt production in rivers flowing into the sea, also making use of additional supporting data on numbers of adult spawners. Determination of whether the threshold value that determines good status is achieved is based on a comparison of estimated smolt production with an estimated potential smolt production capacity. River-specific information provided by ICES WGBAST has been joined with river geometry by HELCOM Secretariat. Attribute information: "River_name" = Name of the river "A_unit" = HELCOM scale 2 Assessment unit "ICES_A_uni" = ICES assessment unit number "Assessment" = HELCOM scale 2 Assessment unit "ICES_Asses" = Number of ICES assessment unit "Estimates_" = Estimates of wild smolt production (*1000) median value "F90_proba" = 90% probability interval "Method_of_" = Method of estimation (1. Bayesian linear regression model, i.e. river model, 2. Sampling of smolts and estimate of total smot run size, 3. Estimate of smolt run from parr production by relation developed in the sae iver, 4. Estimate of smolt run from parr production by relation developed in another river, 5. Inference of smolt production from data derived from similar rivers in the region, 6. Count of spawners, 7. Estimate inferred from stocking of reared fish in the river, 8. Salmon catch in river, exploitation and survival estimate) "Data_sourc" = Data source "Data_origi" = Data originator (natonal instiute) "National_m" = National monitoing (YES/NO) "Use_restri" = Use restrictions (YES/NO)

The assessment results for waterbirds for the HELCOM Third Holistic Assessment of the Ecosystem Health of the Baltic Sea (HOLAS 3) contains the following datasets: Overall seal integrated result map, Grey seal integrated result map, Ringed seal integrated result map, Harbour seal integrated result map, and Harbour porpoise integrated result map. Status is shown in five categories based on the integrated assessment scores obtained in the tool. Biological Quality Ratios (BQR) above 0.6 correspond to good status. The datasets were created using the BEAT tool. https://github.com/helcomsecretariat/BEAT Attribute information: "Mammals_ag" = Aggregated area "SAULEVEL" = spatial assessment unit ID in which the assessment status took place "ECID" = Ecosystem component ID "EClevel" = Ecosystem Component level "EcosystemComponent" = Ecosystem component assessed "BQR" = Biological Quality Ratio "Conf" = Confidence of the assessment (0-1, higher values mean higher confidence) "ConfClass" = Confidence class

This dataset contains the integrated status assessment for seals (grey seals, harbour seals and ringed seals), harbour porpoise and waterbirds (surface-feeding birds, pelagic-feeding birds, benthic-feeding birds, wading birds, and grazing birds) with bycatch for the HELCOM Third Holistic Assessment of the Ecosystem Health of the Baltic Sea (HOLAS 3). Status is shown in five categories based on the integrated assessment scores obtained in the tool. Biological Quality Ratios (BQR) above 0.6 correspond to good status. The datasets were created using the BEAT tool. https://github.com/helcomsecretariat/BEAT Attribute information for mammals: "level_2" = HELCOM sub-basins (name of the scale 2 assessment unit) "HELCOM_ID" = id of the HELCOM assessment unit "SAUID" = ID number for the spatial assessment unit "SAULEVEL" = spatial assessment unit ID in which the assessment status took place "SAU" = Name the spatial assessment unit "ECID" = Ecosystem component id "EClevel" = Ecosystem component assessed level "EcosystemC" = Ecosystem component assessed "Status" = Integrated status category (0-0.2 = not good (lowest score), 0.2-0.4 = not good (lower score), 0.4-0.6 = not good (low score), 0.6-0.8 = good (high score), 0.8-1.0 = good (highest score)) "Conf" = Confidence of the assessment (0-1, higher values mean higher confidence) "ConfClass" = Confidence class "BQR" = Biological Quality Ratio "Status_EQR" = Status of the Biological Quality Ratio Attribute information for waterbirds: "Birds_ag" = Birds group area "GroupName" = Birds group area name "level_2" = Name of the HELCOM assessment unit in scale 2 "HELCOM_ID" = Code of the HELCOM scale 2 assessment unit "BQR" = Biological Quality Ratio "Conf" = Confidence of the assessment (0-1, higher values mean higher confidence) "ConfClass" = Confidence class

This dataset represents the underlying seawater data on core indicator Radioactive substances: Cesium-137 in-fish-and-surface-seawater. The core indicator evaluates the state of the environment using the concentration of the radioactive isotope cesium-137 (137Cs) in herring, in flatfish and in surface waters. Quantitative thresholds are used to evaluate if core indicators Achieve or Fail Good status or if the status is Not assessed. Good status is achieved when concentrations reach levels measured before the Chernobyl accident in 1986 when the biota of the Baltic Sea received the most significant contribution to their level of artificial radionuclides, predominantly in the form of 137Cs. This dataset displays the result of the indicator in HELCOM Assessment Scale 2 (Division of the Baltic Sea into 17 sub-basins). Attribute information: "KEY" = MORS Database unique sample identifier "COUNTRY" = Code for country of observation "YEAR" = Year of observation "STATION" = Unique text that identifies the station "TDEPTH" = Bottom depth at sampling site (m) "SDEPTH" = Sampling depth (m) "ASSESSMENT" = Name of the HELCOM scale 2 assessment unit (subbasin) "NUCLIDE" = Nuclide measured "VALUE_Bq_m" = Value of measurement in Bq/m3

This core indicator evaluates the status of the marine environment based on concentrations of radioactive substances (Cs-137) in seawater and biota. Quantitative thresholds are used to evaluate if core indicators status is "Achieve", "Fail" or "Not assessed". Good status is achieved when concentrations reach levels measured before the Chernobyl accident in 1986. This dataset displays the result of the indicator in HELCOM Assessment Scale 2 (Division of the Baltic Sea into 17 sub-basins) for flatfish. Attribute information: "HELCOM_ID" = Code of the HELCOM scale 2 assessment unit "level_2" = Name of the HELCOM scale 2 assessment unit (subbasin) "Indicator" = Name of HELCOM Core indicator "Type" = Type of indicator "Threshold value" = Threshold value for specific assessment unit "Indicator value" = Value of indicator calculated for specific assessment unit "Status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”)

This core indicator evaluates the status of abundance of wintering waterbirds in the Baltic Sea region, here visualized for grazing feeders. The wintering waterbirds are considered to reflect good status when at least 75% of the considered species deviate less than 30% downwards (species laying more than one egg per year) or 20% downwards (species laying one egg per year) from the baseline condition during the reference period 1991-2000. This dataset displays the result of the indicator in HELCOM Assessment Scale 3 (Division of the Baltic Sea into 17 sub-basins and further division into coastal and offshore areas). Attribute information: "HELCOM_ID" = ID of the HELCOM scale 3 assessment unit "country" = Country "Group area" = Name of the group area "level_2" = Name of scale 2 HELCOM assessment unit (subbasin) "level_3" = Name of scale 3 HELCOM assessment unit "Area (km2)" = Area of HELCOM assessment unit "coastal" = HELCOM ID of the coastal areas "open_sea" = Open sea assessment unit name "Abundance" = Assessed parameter "Threshold" = Threshold value "Wading feeders" = Results for the category "Wading feeders status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”) "Surface feeders" = Results for the category "Surface feeders status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”) "Pelagic feeders" = Results for the category "Pelagic feeders status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”) "Benthic feeders" = Results for the category "Benthic feeders status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”) "Grazing feeders" = Results for the category "Grazing feeders status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”) "AULEVEL" = Assessment unit level used for the indicator

This dataset represents the underlying data on core indicator in Abundance of key coastal fish species 2018. The core indicator evaluates the abundance of typical species of fish, such as perch and flounder, in the coastal areas of the Baltic Sea, to assess environmental status. Quantitative thresholds are used to evaluate if core indicators status is Good, Not good or Not assessed. As a rule, good status is achieved when the abundance is above a set site and species-specific threshold value. This dataset displays the result of the indicator in HELCOM Assessment Scale 3 (Division of the Baltic Sea into 17 sub-basins and further division into coastal and offshore areas). Attribute information: "COUNTRYID" = Country code "ORGANIZATI" = Data provider "AREANAME" = ICES area "Assessment" = Name of scale 3 HELCOM assessment unit "IndicatorI" = Name of the indicator (abbreviation) "SpeciesId" = Species "IndicatorV" = Result value for the indicator "MethodId" = Catch method "GearType_N" = Gear type of catch "Season_NAM" = Season

This dataset represents the Integrated biodiversity status assessment for pelagic habitats using the BEAT tool. Status is shown in five categories based on the integrated assessment scores obtained in the tool. Biological Quality Ratios (BQR) above 0.6 correspond to good status. Open sea areas were assessed based on the core indicators ‘Zooplankton mean size and total stock’ and ‘Chlorophyll-a’, as well as the pre-core indicator ‘Cyanobacterial bloom index’ . Coastal areas were assessed by national indicators. This dataset displays the result of the integrated biodiversity status in HELCOM Assessment unit Scale 4 (Division of the Baltic Sea into 17 sub-basins and further division into coastal and off-shore areas and division of the coastal areas by WFD water types or water bodies). Attribute information: "BQR" = Biological Quality Ratio "Confidence" = Confidence of the assessment "HELCOM_ID" = Code of the HELCOM assessment unit "Country" = Country of coastal assessment unit/ open sea "Level2" = HELCOM sub-basins (name of the scale 2 assessment unit) "Name" = Name of the HELCOM scale 4 assessment unit "Area_km2" = Area of assessment unit "AULEVEL" = scale of the assessment unit "HID" = assessment unit ID by country "SAUID" = ID number for the spatial assessment unit "EcosystemC" = Ecosystem component assessed "Confiden_1" = Confidence of the assessment (0-1, higher values mean higher confidence) "Total_numb" = Number of indicators used in assessment "STATUS" = Integrated status category (0-0.2 = not good (lowest score), 0.2-0.4 = not good (lower score), 0.4-0.6 = not good (low score), 0.6-0.8 = good (high score, 0.8-1.0 = good (highest score))

The dataset contains the compilation of the abundance and distribution of Baltic seals from the data submitted by HELCOM contracting parties to the data call for HOLAS 3. Data was received from DE, DK, EE, FI, PL and SE. The dataset contains a geodatabase with the harmonized data. Data were provided in point, line and polygon format.