State of benthic habitats and seafloor integrity

Benthic ecosystems in the OSPAR Maritime Area are influenced by open Atlantic oceanic currents, geographical and topographical factors, depth variations and temperature and salinity ranges. This wide range of environmental conditions in turn produces a rich and diverse array of benthic ecosystems, from intertidal mudflats to biogenic reefs (https://www.emodnet-seabedhabitats.eu/).

Anthropogenic pressures have caused changes in the extent, distribution, condition and functioning of benthic habitats, with increased degradation in some, particularly those highly sensitive to human pressures. During recent decades, several habitats have been identified as in need of special protection and conservation measures, notably through European Union Directives and by other regional bodies: Natura 2000; Marine Strategy Framework Directive (MSFD), Baltic Marine Environment Protection Commission, Convention for the Protection of the Marine Environment and the Coastal Region of the Mediterranean and The Commission on the Protection of the Black Sea Against Pollution. For OSPAR, these habitats are listed under Threatened and/or Declining Species and Habitats.

For this Quality Status Report (QSR 2023), the assessments of the state of broad-scale and listed benthic habitats in the OSPAR Maritime Area have been undertaken using a variety of indicators and assessment methods applied at different scales. Most of the indicators have been further developed and improved since the publication of the 2017 OSPAR Intermediate Assessment . The key messages from the results of the indicator and listed habitat status assessments have been summarised for each of the five OSPAR Regions in Table S.1, including an overall assessment of confidence. The availability of habitat data and the limited access to high-resolution pressure data from anthropogenic activities present a key challenge to the assessment of benthic ecosystems. Currently, there are large areas of OSPAR Regions with very limited or no monitoring data. Pressure-state-impact relationships, particularly in regard to exposure levels and the recovery of some sensitive habitats, are not always well understood. This and data paucity are the key factors affecting the levels of confidence in the assessments results (Table S.1).

Table S.1: Regional assessment summaries of benthic Common Indicators and OSPAR listed threatened and /or declining habitats

The OSPAR Common Indicators have not yet been adapted for and applied to the Arctic Waters (OSPAR Region I). Therefore, the ecosystem state of the Arctic Waters in the OSPAR Maritime Area has been assessed with the best available data and scientific knowledge.

There is some evidence available for selected areas of the Arctic Waters and the Wider Atlantic, but this is limited to third party assessments, the status of some of the OSPAR threatened and/or declining habitats and pilot assessments of candidate indicators. The spatio-temporal coverage of these assessments is limited, which in turn limits the comparability of the results.

For the Greater North Sea, Celtic Seas and Bay of Biscay and Iberian Coast, quantitative approaches have been applied through the use of regional Common Indicators, which represent an evaluation of status and assessment using common standards of methodology and data formats. Status assessments from the OSPAR-listed threatened and / or declining habitats are also available for these Regions. However, gaps still remain, in particular in terms of the types of pressures addressed, the limited data and the cumulative effects, which prevents the integration of indicators at this stage. The results from indicators cover a wide range of habitat types.

Thanks to the common methodological standards, the lines of evidence (Indicator Assessments, other assessments or third-party assessments) mostly concur, although a minor proportion show some deviation, notably due to differences in the indicators and related methods used between Regions (common and candidate indicators), knowledge gaps and current limitations in methods, which still enable some subjective interpretations of the results.

Despite the large amount of effort invested to develop indicators, quantitative integration is not possible at this stage. This is due to a combination of factors, in particular the lack of agreed regional thresholds alongside the limited coverage of indicator results across some of the assessment units. 

To facilitate overall visualisation, the results of the Indicator Assessments are presented.

Table S.2 and Figure S.2, Figure S.3, Figure S.4, Figure S.5 and Figure S.6 highlight that not all indicators were assessed in all OSPAR Regions due to lack of data or lack of policy support. As previously noted, OSPAR Common Indicators have not yet been adapted for or applied to the Arctic Waters and Wider Atlantic Regions, although the availability of limited data has facilitated a pilot assessment for two indicators in discrete areas within the Arctic Waters and the Wider Atlantic to support the further development of these indicators for these regions.

The assessment of Common Indicators and the pilot assessment of candidate indicators (Table S.2) have been used to assess different aspects of benthic ecosystems, namely the level of disturbance and risks of physical loss to the seafloor (MSFD broad habitat types and OSPAR List of threatened and declining habitats), changes in benthic species diversity, impacts on sensitive species and the status of benthic communities in relation to eutrophication pressures (nutrient and organic enrichment). The assessment units (AUs) used in the analysis reflect the boundaries set up for MSFD and UK Marine Strategy reporting purposes (Figure S.1).

Table S.2 : Overview of the availability per OSPAR Region of Common Indicator results (marked as X in white cells) and the pilot assessment of Common Indicators (marked as (X) in pale grey cells); or where there is no indicator at all (dark grey cell). AU = assessment units. UK = United Kingdom

Figure S.1: Maps of the agreed benthic assessment units overlaying OSPAR Regions

The results presented relating to the Condition of Benthic Habitat Communities: Assessment of some Coastal Habitats in Relation to Nutrient and/or Organic Enrichment (BH2a) in Figures S.3 and S.4 indicate that most of the water bodies for which data were provided, in the Greater North Sea, Celtic Seas and Bay of Biscay and Iberian Coast, have benthic habitats classified as in good biological status, according to the European Union Water Framework Directive (WFD, 2000/60/EC). For the three OSPAR Regions the assessment of invertebrates was applied to 72% of coastal water bodies (Figure S.2) and 59% of coastal water bodies for the condition of benthic vegetation (Figure S.3). The WFD quality status for the condition of benthic invertebrates was good or high in 79% of the coastal water bodies assessed. The condition of benthic vegetation was good or high in 86% of the coastal water bodies assessed. However, local eutrophication-impacted areas were highlighted in the 2010 and 2016 reporting cycles.

The Sentinels of the Seabed (BH1) Common Indicator Assessment evaluated the level of disturbance to the main benthic habitats affected by bottom-contact fishing in the Common Indicator Assessment units in the Bay of Biscay and Iberian coast Region from 2009 to 2020 (QSR) and from 2016 to 2020 (MSFD). 

The assessment showed that bottom trawling was widely distributed over the continental shelf of the area considered (Figure S.2). This geographical distribution results in the intensity of the fishing effort being primarily concentrated at depths shallower than 500 m and mainly shallower than 200 m. Consequently, the Gulf of Cadiz and the Gulf of Biscay assessment units, which mostly comprise the continental shelf, are trawled to a greater extent and thus have a greater disturbed area. 

When considering disturbance across Broad Habitat Types (BHT) within the assessed area, high disturbance was most significant in circalittoral coarse sediment, offshore circalittoral mixed sediment and offshore circalittoral mud (80% highly or moderately disturbed). These disturbance results were the product of interaction between the moderate to high intensity of trawling and the sensitivity of the habitats to that pressure. The least disturbed habitat type was upper bathyal sediment, at 46% highly or moderately disturbed. The assessment of the South Iberian Atlantic was not reliable because of a lack of Portuguese data.
 

Figure S.2: Summary outputs of disturbance to benthic habitats for bottom trawling assessed by Sentinels of the Seabed (BH1) Common Indicator over the period 2009 to 2020 (QSR assessment period). The spatial distribution of disturbance across the Common Indicator Assessment units is presented on the map. The pie chart plots the percentage of assessment unit area for each disturbance level. This summary did not include data from the Portuguese fleet (VMS unavailable)

Despite the data gaps for many water bodies, this fine-scale Common Indicator Assessment (sub-regions and coastal water bodies) enabled the identification of regional variations and the main locally impacted areas for benthic invertebrates (Figure S.2) and vegetation communities (Figure S.3). The main impacted areas, notably for benthic vegetation, are persistent between 2010 and 2016, all along the Dutch and Danish coasts and the north-west coasts of France. The total area of assessed / reported water bodies increased significantly between 2010 and 2016 in most Regions (except the assessment unit Northern Iberian Atlantic), which led to better representativity, with both new good and bad WFD quality status areas.

The assessment of the Condition of Benthic Habitat Communities: Margalef diversity in Region II (Greater North Sea) (BH2b) (Figure S.5) has shown that the relative diversity of benthic communities is higher in offshore circalittoral habitats compared with circalittoral and infralittoral habitats, where low species diversity was found.

Relative diversity still seems to be in a moderate or rather good state in offshore circalittoral habitats, regardless of the expected relatively high fishing pressure. It should be noted that data from 2016-2021 were lacking for extensive areas, so on the basis of the impact assessments from BH3a (see also Figure S.6) a decrease in quality might be expected in the near future. Benthic diversity is relatively low in shallow coastal waters, where various pressures (e.g., eutrophication and diffuse pollution) can affect habitat condition even where fishing appears to be limited, according to the available pressure data. The pattern is especially evident in the Southern - and possibly Central – North Sea. The shallow benthic habitats of the Kattegat appear to be in a poor state; besides fisheries, it is expected that increased variability in low salinity water inflow from the Baltic plays a role. In general, benthic habitat quality status seems better in the Channel (regardless of high fishing pressure) and the Norwegian Trench. There and in the Central North Sea, efforts to improve the representativity of benthic community sampling programmes could improve the reliability of assessments.

Figure S.5: Summary outputs of the Margalef Species Diversity (BH2b) assessment (2016-2021). Bars show proportion (area) of assessment unit with relative diversity level, where the number of assessed habitats under each diversity category is indicated
* The proportion of uncertain or unassessed area (grey bars) is slightly underestimated as it does not include two littoral BHTs for all assessment units and three lower bathyal and abyssal BHTs in the case of the Norwegian Trench.

Figure S.6 summarises the assessment outcomes for two BH3 indicators:

• BH3a: Extent of Physical Disturbance to Benthic Habitats: Fisheries with mobile bottom-contacting gears ;
• BH3b: Extent of Physical Disturbance to Benthic Habitats: Aggregate Extraction .

The assessment of indicator BH3a (red colourway, Figure S.5) evaluated the benthic habitat disturbance in the North-East Atlantic associated with bottom-contact fishing over two time frames (QSR:2009 to 2020; MSFD:2016 to 2020). Seafloor disturbance caused by fishing occurred in all broad habitat types, affecting 48% of the assessed area in 2016-2020, and 53% in 2009-2020.

The assessment indicated a ubiquitous distribution of anthropogenic pressure across parts of the OSPAR Maritime Area in habitats where bottom-contact fishing occurs (< 800 m deep). All Broadscale Habitat Types (BHT) had high and/or moderate disturbance, with offshore circalittoral mud having the greatest proportion of high disturbance and offshore circalittoral coarse sediment the greatest proportion of low disturbance. 

When considering the spatial distribution of disturbance, the greatest proportions of high and moderate disturbance occurring together were in the Gulf of Biscay and the Southern North Sea, whereas the greatest proportion of high disturbance alone was in the Gulf of Cadiz and the greatest proportion of low disturbance was in the Channel. 

Zero disturbance was found in approximately half the total area of Common Indicator Assessment units in both the QSR (2009-2020) and the MSFD assessment (2016 – 2020) periods. However, gaps in the coverage of VMS (Vessel Monitoring System) data highlighted potential underestimations of disturbance in some areas and habitats. The aforementioned limitations associated with VMS data availability should be addressed in future assessments so as to facilitate more robust findings. 

The results of Common Indicator Extent of physical disturbance to benthic habitats: Aggregate extraction (BH3b) are presented alongside the results from Common Indicator Extent of physical disturbance to benthic habitats: Fisheries with mobile bottom-contacting gear (BH3a) in Figure S.5, using a grey colour scheme. They show that disturbance from aggregate extraction was limited in extent, with high-intensity pressure localised to discrete licensed areas, where permitted by regulators. Disturbance could only be calculated where sufficient extraction pressure data were available. Owing to limitations in commercially sensitive extraction activity data, disturbance results are confined to the exclusive economic zones (EEZs) of the data providers. 

Habitats impacted by extraction pressure typically showed moderate or high disturbance. Across all areas assessed, the sediments typically targeted by the aggregate industry (mixed sediment, coarse sediment, and sand) had the greatest proportions of area with disturbance. However, the total disturbance area for any single BHT across all assessment units remained less than 0,5% of the total habitat area. Additionally, within assessment units, the proportion of any habitat area under disturbance was also low, with offshore circalittoral rock and biogenic reef being the only BHTs with an area under greater than 1% disturbance in both the QSR and the MSFD assessments. 

Changes in the areas of annual disturbance did not show any clear increasing or decreasing trends between 2009 and 2020. The variation in United Kingdom waters throughout the time series broadly followed the total active annual dredging area reported by the data provider (BMAPA, 2010 to 2021).

Figure S.6: Assessment results for risk of physical disturbance to benthic habitats, as calculated with the BH3a indicator for bottom-contact fishing gears and the BH3b indicator for commercial aggregate extraction, across the QSR 2023 assessment period (2009 to 2020). Disturbance caused by fishing activities is calculated as the percentage of the assessment unit under different levels of disturbance (red colourway), and disturbance caused by commercial aggregate extraction (grey colourway) is calculated as the percentage of disturbance in the areas where the activity is occurring (per assessment unit); shades of grey represent different levels of disturbance

Across all assessment units, abyssal habitats (deeper than 2 000 metres) have the highest habitat extent amounting to 30% of total habitat across all benthic broad-scale habitat types, followed by offshore circalittoral sand (18%) and upper bathyal sediments (14%) (Figure S.7). Physical disturbance remains the main widespread pressure caused by human activities and contributes to a reduction in diversity and changes in sensitive benthic species communities and habitats across the OSPAR Regions. This thematic assessment has highlighted that the highest levels of physical disturbance due to abrasion by bottom trawling fisheries occurred in infralittoral and circalittoral offshore soft habitat types, while coastal habitat benthic communities' diversity and structure were both affected by - probably - several pressure types.

Figure S.7: The percentage of the total OSPAR Common Indicator area covered by each BHT. Additionally, the percentage of the total assessed area where there were no EUNIS data and where no EUNIS to BHT translation was possible is also represented

The recent status assessments of specific threatened and / or declining habitats (OSPAR Agreement 2008-06) indicate that these are generally in poor status. Most of the currently available evidence indicates a declining or not improved condition. Some habitats (such as Ostrea edulis and Zostera beds) also showed a decrease in distribution and extent in some regions. There has been no indication of any improved status in sea-pen and burrowing megafauna habitats. This is further supported by the BH3a indicator results for threatened and declining habitats, which showed that close to 90% of sea-pen and burrowing megafauna habitats were under high risk of disturbance in all assessment units where the habitat was present. Oceanic ridges and hydrothermal vents have been assessed as being in good status, their condition having improved since the last assessment. Detailed evidence and assessment results for these habitats can be found in the relevant sections below for each OSPAR Region.

Summary results of benthic habitat quality status by assessment unit and OSPAR Region

The OSPAR quality status assessments of benthic habitats, both broad habitat types and habitats listed as threatened and / or declining, were undertaken using a variety of assessment methods and scales developed over a number of years (See each indicator’s CEMP guidelines and method section in the Indicator Assessment Sheets). Areas with sufficient data were assessed using common and candidate indicators for agreed pilot studies (Table S.2). All indicator results are summarised for each previously agreed assessment unit, which in some cases overlap OSPAR Regions (Figure S.6). Those habitats classified as threatened and declining by OSPAR Agreement 2008-06 were assessed using a combination of published data and expert judgement. The Arctic Waters section is compiled from a published OSPAR Third Party Assessment: State of the Arctic Marine Biodiversity Report . The Wider Atlantic chapter is mainly based on the assessment of OSPAR listed habitats and pilot studies of BH3a in several parts of overlapping assessment units.

Arctic Waters: Polar benthic habitats

No Common Indicators or agreed assessment units with indicator results (only a small area with pilot assessment results for BH3a)

In Arctic Waters, no common OSPAR indicators have been developed. Without any European or OSPAR common methodological standards, almost all of this area was assessed using references to published studies, notably from the Arctic Council, local experts’ judgement.

The status of benthic habitats in Arctic Waters is descriptive and based on a scientific article concerning the Polar Seas’ baseline (Jørgensen et al., 2022), together with information from the most updated ICES reports on benthic communities, and from the Arctic Council’s Conservation of Arctic Flora and Fauna (CAFF) biodiversity working group. The trends detected are mainly related to climatic impacts which underlines the crucial role of climate change in Arctic benthic habitats. However, the specific impacts of human activities have not yet been well studied and documented. Therefore, this section mainly describes the state of the progress made towards methodological standards (e.g., indicators) and common baselines for Arctic benthic habitats.

According to the latest State of the Arctic Marine Biodiversity Report (CAFF, 2017), only one Arctic sub-region presents sufficient data to be assessed by CAFF. This is the Barents Sea, for which the changes over both long- and short-term time spans in macrobenthos spatial patterns are available. Outside the Barents Sea, there are only very limited data available on benthic habitats, biodiversity and abundance, thus pre-empting any assessment at OSPAR sub-regional scale or even by an Arctic third party.

Within the Arctic Waters of the OSPAR Maritime Area, Jørgensen et al., (2022) present data from the eastern and western Barents Sea, Icelandic and Faeroe waters and north-east Greenland. The Norwegian Sea is not included at this time, since benthic mapping is at an early phase for the deeper waters and is mostly done near the Norwegian coastline and the continental slope towards the deep-sea basins central to the Norwegian Sea.

In 2022 a baseline of benthic community biodiversity was established (Jørgensen et al., 2022). The baseline was created on the basis of megabenthic (organism size > 1 cm) data taxa groups reviewed at regional levels, as species diversity would have made comparisons difficult in this circumpolar study. Infauna and free-swimming taxa were excluded from the analyses. This megabenthos diversity baseline can be used to compare any change in status based on future monitoring efforts. The baselines for averaged standardised biomass were higher in Icelandic and Faeroese waters and lower in the Barents Sea. The lowest average standard abundance was found in the south-eastern Barents Sea and southern Iceland waters.

Figure S.8: Average standardized number of taxa (a) and standard deviation (SD) of average number of taxa (b) within each grid cell (50 km × 50 km). Note that this representation is based on a highly uneven effort among (and much less so within) regions and is intended to provide a cautious indication of patterns within regions. Source: Jørgensen et al., 2022

Three megabenthic functional traits were selected – ‘body form’, ‘adult movement’ and ‘skeleton’ – as possible vulnerable traits for impacts. When the movement and body form traits were combined into a ‘sessile and upright’ combination, few areas had more than 50% of taxa with these traits, while the south-eastern Barents Sea usually had less than 25%. These trait combinations can reflect habitat / species vulnerability to seabed disturbances and may be considered to be used for future indicator development to assess this specific human activity impact.

The most recent ecosystem state report from Arctic waters is the ICES report from its Working Group on Integrated Assessments of the Barents Sea (WGIBAR) (ICES, 2022). The Group’s long-term monitoring data series on the dynamics of distribution, biomass and abundance shows that the large-scale distribution of megabenthos has been relatively stable since 2004. The biomass and species diversity of the main taxonomic groups generally followed previous spatial patterns of distribution. However, in 2020 the distribution and biomass/abundance of megabenthos were below the long-term mean. This information is linked to a moderate certainty since the surveys did not cover the entire Barents Sea. The fluctuation in biomass is positively correlated with increasing sea temperature due to climate change .

OSPAR acknowledges the need for a better understanding, based on quantity, periodicity and regionality of carbon supply and demand in the deep-water Arctic basins, in order to evaluate future changes in these benthic ecosystems. This need is also highlighted by ICES (2020). As change from permanently ice-covered to seasonally ice-covered regions occurs, such studies would also be crucial for assessing the state and trends in the benthos of these ecosystems.

Assessment of the status of OSPAR listed threatened and/or declining habitats in Arctic Waters

The status of maerl beds in the Arctic Waters Region remains unknown. These species can form extensive beds, mostly in coarse clean sediments of gravels and clean sands or muddy mixed sediments, which occur either on the open coast, in tide-swept channels or in sheltered areas of marine inlets with weak current (OSPAR, 2019). However, some of the maerl beds in this Region exhibit the best condition in the OSPAR Maritime Area. More than in other regions where this habitat occurs, the status assessment predicts that increasing ocean acidification and temperatures will cause a slow but significant reduction in condition and distribution over coming decades.

The assessment of the coastal habitat eelgrass beds (Zostera beds) in the Arctic Waters Region shows an overall declining trend in distribution, extent and condition. However, the current status of the Zostera beds in Greenland is unknown. It is also concerning that there are significant data and knowledge gaps and that maps of eelgrass beds are patchy. The emerging impacts from climate change include darkening of coastal waters and sediment resuspension, which exacerbates the stressors on eelgrass beds and makes it even more important to manage the existing threats from eutrophication and coastal development and extraction, which are assessed as being on the increase in Arctic Waters. However, there is also a possibility that climate change is causing the northern distribution limit of Zostera beds to expand.
It should be noted that for the intertidal mudflats habitat no information was available to enable an assessment of its status in Arctic Waters at this stage.

The condition of deep-sea sponge aggregations was shown to decrease in a four-year study of the Schulz Bank, which indicated a decline in sponge density in areas affected by human activities. Deep-sea sponge aggregations occur at shallowed depths along the Norwegian fjords, more than anywhere else in the OSPAR Maritime Area. The same is true for Lophelia reefs, some of which occur at depths of 40 m along the Norwegian coast, while in other Regions they occur at depths of 200 to 1 200 m. Due to extensive mapping efforts since the last assessment in 2009, a significant number of new occurrences of Lophelia reefs have been detected in the Norwegian and Barents Seas. This is, however, not considered to be an indication of increased extent, and in fact the extent of the habitat within Arctic Waters is likely to still be decreasing due to fishing pressures. However, there are sub-regional differences indicating where activities to minimise destructive impacts on the marine ecosystems and Lophelia reefs are in place. (See case study for the Response measures (on benthic habitat) of the Norwegian EEZ (Region I)). Selected Lophelia reefs within Marine Protected Areas (MPAs) have been monitored regularly since 2012. This has revealed the overall health of the reefs to be in a good state and their condition is assessed as stable. In Arctic Waters, 13% of Lophelia reefs are assessed as being within MPAs. 

Oceanic ridges with hydrothermal vent fields were assessed as remaining in good condition in Arctic Waters. There is an indication that longline fishing may be occurring along the upper bathyal ridges of vent fields, which could potentially result in fishing gear contacting the bottom and breaking the fragile vent chimneys. None of the known habitat occurrences are within MPAs. However, other protective measures are in place, such as local fisheries restricted areas (FRAs), where the pressure from fishing activities on benthic habitats appears to be slightly reduced. (See Case study for Norway Region I for more information).

Seamounts occur in the northern Arctic as well as along the Mid-Atlantic ridge. Few seamounts are of interest for commercial fishing activities, which have a negative impact on the communities associated with an exposed seamount, resulting in a deteriorating condition. There is a considerable knowledge gap regarding seamount communities, and for seamounts within national waters there are ongoing activities to collect more information through individual research programmes.

Table S.3: Summary results of the assessment of the OSPAR threatened and /or declining habitats in Arctic Waters

Legend:

Previous status assessment:
Regions where species occurs (○) and has been recognised by OSPAR to be threatened and/or declining (●)

Trends in status (since the assessment in the background document):

Status of criterion assessed:

The level of confidence for the assessment for the Arctic Waters is considered Low 

• Level of evidence: low. The assessment is based on published research and third-party assessments, but gaps were observed in the spatial coverage of the biological information available. 
• Degree of agreement: low.  The status assessments of OSPAR listed habitats mostly agree with the summary overview but cover only a small part of this Region.

Greater North Sea - Sandy, muddy and productive benthic habitats

Five assessment units with indicator results: BH2a, BH2b, BH3a, BH3b (pilot assessment BH4)
The Greater North Sea Region is exposed to widespread and generally high intensity and frequency of disturbance from bottom trawling fisheries, except for the Central North Sea where there are generally lower levels of disturbance. Disturbance from aggregate extraction activities affects a small proportion of the Greater North Sea and is mostly concentrated in the Southern North Sea and the Channel. The offshore circalittoral mud areas, in particular, tend to be highly disturbed at OSPAR regional scale due to high-pressure levels in combination with expected high habitat sensitivity. In the Southern North Sea and the Channel, the habitats mostly exposed to high levels of disturbance are offshore circalittoral rock and biogenic reefs and circalittoral coarse sediments. The observed disturbance from fisheries is in line with the observed levels of diversity in the benthic community, which is mostly low or moderate in high-disturbance areas. In the Southern North Sea, however, circalittoral mud areas tend to have high diversity despite the observed high level of disturbance, although this could be caused by the limited data available for some areas.

Habitat loss from the placement of structures is highest in the Central and Southern North Sea, mainly induced by a higher density of oil and gas platforms and the pipelines needed for transporting the products. A higher probability of sediment changes caused by trawling is observed in the Channel and Southern North Sea, whereas in the Norwegian Trench and the Kattegat fishing pressure is considered to pose a lower risk of loss.

The eutrophication status of benthic habitats in coastal waters is generally good/high but, particularly in several areas of the Southern North Sea and Kattegat, eutrophication is still impacting benthic invertebrate communities and even more macrophyte communities.
OSPAR threatened and declining habitats are not in a good state and sometimes deterioration compared with the previous assessment has been observed (e.g., maerl beds). 

The level of confidence for the assessment for the Greater North Sea is considered medium

• Level of evidence: medium. The assessment is based on multiple lines of evidence, but gaps were observed in the spatial coverage of the biological information available. 
• Degree of agreement: medium. The indicators and status assessments of OSPAR listed habitats mostly agree, although a minor proportion show some deviation (i.e., the indicators BH3a and BH2b do not align for offshore circalittoral mud areas in the Southern North Sea).

Faroe-Shetland waters

This assessment unit (AU) was assessed using only indicator BH3a for disturbance caused by fishing activities. During 2009-2020, disturbance occurred in 15% of the area. Moderate disturbance covered the largest proportion of the assessment unit (12%), followed by high and low (3% and <1% respectively). Zero disturbance occurred throughout 84% of the assessment unit due to areas with no reported swept area ratio values. However, most of the assessment unit consisted of deep-sea habitats where bottom contact fishing is unlikely to be possible due to the depth of the seafloor.

The percentage area disturbed by fishing activities decreased slightly to approximately 6% during 2016-2020. Moderate disturbance covered the largest proportion of the assessment unit (6%), followed by high and low (both <1%). A large proportion (92%) of this assessment was under zero disturbance.

The Central North Sea

Assessment Unit x Indicator Results x Broad Habitat Types

Central North Sea x Condition of Benthic Habitat Communities: Assessment of some Coastal Habitats in Relation to Nutrient and/or Organic Enrichment (BH2a) 

Coastal water body status:

poor/bad

moderate

high/good

no data

BH existing in AU coastal water bodies

Broadscale habitat type	BH2a invertebrates (< 2009) % of the coastal waterbodies (CWB) area under each quality status	BH2a vegetation (< 2009) % of the coastal waterbodies (CWB) area under each quality status	BH2a invertebrates (2010-2015) % of the coastal waterbodies (CWB) area under each quality status		BH2a vegetation (2010-2015) % of the coastal waterbodies (CWB) area under each quality status
Littoral rock and biogenic reef			not assessed
Littoral sediment
Infralittoral rock and biogenic reef			not assessed		not assessed
Infralittoral coarse sediment					not assessed
Infralittoral mixed sediment					not assessed
Infralittoral sand					not assessed
Infralittoral mud					not assessed
Circalittoral rock and biogenic reef			not assessed		not assessed
Circalittoral coarse sediment					not assessed
Circalittoral mixed sediment					not assessed
Circalittoral sand					not assessed
Circalittoral mud					not assessed
Offshore circalittoral rock and biogenic reef			not assessed	not assessed
Offshore circalittoral coarse sediment			not assessed	not assessed
Offshore circalittoral mixed sediment			not assessed	not assessed
Offshore circalittoral sand			not assessed	not assessed
Offshore circalittoral mud			not assessed	not assessed
Upper bathyal rock and biogenic reef	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Upper bathyal sediment	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Lower bathyal rock and biogenic reef	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Lower bathyal sediment	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Abyssal	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU

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Central North Sea x Condition of Benthic Habitat Communities: Margalef diversity in Region II (Greater North Sea) (BH2b)

Relative Margalef diversity (0-1):

Relative high diversity (0,8-1)

Moderate diversity (0,6-0,8)

Relative low diversity (0-0,6)

Uncertain due to very low sample size or not assessed

    ↘       Significant decrease
    ↗       Significant increase
   ↔       No significant changes in relative Margalef diversity
    ?       Unknown: Data for period of concern or period to compare with are lacking

2009-2021 is compared with 1998-2008; 2016-2021 is compared with 2009-2015
In case no data available for 2016-2021: Results for 2009-2015 are presented for 2016-2021, however with lowered confidence level
Data based on grab-core samples; trends extracted from either 'grab-core' samples or 'small core' samples (presented when observed based on one or the other)

Broadscale habitat type	BH2b (2009-2021)	BH2b (2016-2021)
Littoral rock and biogenic reef	Not assessed	Not assessed
Littoral sediment	Not assessed	Not assessed
Infralittoral rock and biogenic reef	Not assessed	Not assessed
Infralittoral coarse sediment	Not assessed	Not assessed
Infralittoral mixed sediment	0,46 ?	0,46 ?
Infralittoral sand	0,33 ?	0,33 ?
Infralittoral mud	Not assessed	Not assessed
Circalittoral rock and biogenic reef	Not assessed	Not assessed
Circalittoral coarse sediment	0,64 ?	0,71 ?
Circalittoral mixed sediment	0,38 ?	0,38 ?
Circalittoral sand	0,78 ?	0,74 ↔
Circalittoral mud	0,86 ?	0,86 ?
Offshore circalittoral rock and biogenic reef	Not assessed	Not assessed
Offshore circalittoral coarse sediment	0,64 ?	0,64 ↔
Offshore circalittoral mixed sediment	0,90 ?	0,90?
Offshore circalittoral sand	0,69 ?	0,71 ↔
Offshore circalittoral mud	0,65 ?	0,65 ↔
Upper bathyal rock and biogenic reef	not in assessment	not in assessment
Upper bathyal sediment	Not assessed	Not assessed
Lower bathyal rock and biogenic reef	not in assessment	not in assessment
Lower bathyal sediment	not in assessment	not in assessment
Abyssal	not in assessment	not in assessment

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Central North Sea x Extent of Physical Disturbance to Benthic Habitats: Fisheries with mobile bottom-contacting gears (BH3a)

Broadscale habitat type	BH3 fisheries abrasion 2009-2020 (% habitat area within assessment unit under each disturbance group)					BH3 fisheries abrasion 2016-2020 (% habitat area within assessment unit under each disturbance group)
	Zero	Low	Moderate	High	Unassessed disturbance	Zero	Low	Moderate	High	Unassessed disturbance
Littoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Littoral sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral rock and biogenic reef	43,15337	37,17934	9,04347	10,62380	0	54,93951	26,87692	9,05856	9,12501	0
Infralittoral coarse sediment	7,65484	83,07380	9,26864	0,00272	0	8,79493	85,21820	5,98414	0,00272	0
Infralittoral mixed sediment	36,82524	0	59,55763	3,61714	0	37,13907	0	59,24379	3,61714	0
Infralittoral sand	43,74813	38,62905	10,86117	6,76165	0	51,21773	38,66666	3,54804	6,56757	0
Infralittoral mud	34,67498	56,06892	4,66623	4,58986	0	35,417090	54,96213	7,50231	2,11848	0
Circalittoral rock and biogenic reef	12,69351	47,64400	26,12381	13,53868	0	26,64675	38,44316	24,38447	10,52562	0
Circalittoral coarse sediment	2,36813	53,34541	43,23494	1,05152	0	4,09010	65,43031	29,42807	1,05152	0
Circalittoral mixed sediment	4,07254	53,28732	23,58745	19,05269	0	8,69730	46,83148	31,68367	12,78755	0
Circalittoral sand	5,93162	41,89641	47,76012	4,41186	0	11,14035	42,25907	42,70462	3,89596	0
Circalittoral mud	10,65709	47,27716	24,06617	17,99958	0	18,83752	37,02675	32,36013	11,77560	0
Offshore circalittoral rock and biogenic reef	0,46755	33,13991	20,50109	23,41323	22,47822	10,18377	33,47177	15,63833	18,82630	21,87983
Offshore circalittoral coarse sediment	2,99498	95,05430	1,78033	0,17038	0	7,19322	91,58530	1,10703	0,11445	0
Offshore circalittoral mixed sediment	4,64818	72,81707	22,04719	0,48756	0	8,41025	71,76475	19,60864	0,21636	0
Offshore circalittoral sand	5,86846	34,09728	59,85679	0,17748	0	15,53969	35,88068	48,47122	0,10841	0
Offshore circalittoral mud	1,12589	8,42769	2,72797	87,71846	0	3,30255	7,71834	9,65283	79,32628	0
Upper bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Upper bathyal sediment	0	0	1,24071	98,75929	0	0,12489	0	14,33602	85,53908	0
Lower bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Lower bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Abyssal	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed

---

Central North Sea x Extent of Physical Disturbance to Benthic Habitats: Aggregate Extraction (BH3b)

Broadscale habitat type	BH3 aggregates extraction 2009-2020 (% habitat area within assessment unit under each disturbance group, note 'Zero' disturbance not assessed)				BH3 aggregates extraction 2016-2020 (% habitat area within assessment unit under each disturbance group, note 'Zero' disturbance not assessed)
	Low	Moderate	High	Unassessed disturbance	Low	Moderate	High	Unassessed disturbance
Littoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Littoral sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral coarse sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral mixed sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral sand	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral mud	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Circalittoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Circalittoral coarse sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Circalittoral mixed sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Circalittoral sand	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Circalittoral mud	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral coarse sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral mixed sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral sand	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral mud	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Upper bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Upper bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Lower bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Lower bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Abyssal	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed

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Central North Sea x Pilot Assessment of Area of Habitat Loss (BH4)

Broadscale habitat type	BH4 Sealed loss	BH4 Unsealed loss (by trawling)
	% estimated loss	No loss	% low risk	% moderate risk	% high risk
Littoral rock and biogenic reef	Not assessed
Littoral sediment	Not assessed
Infralittoral rock and biogenic reef	<0,01 0	100 91,8	0 0	0 8,2	0 0
Infralittoral coarse sediment	0	95,2	4,8	0	0
Infralittoral mixed sediment	0	100	0	0	0
Infralittoral sand	0	100	0	0	0
Infralittoral mud	0	49,2	50,8	0	0
Circalittoral rock and biogenic reef	<0,01 0	100 21	0 0	0 79	0 0
Circalittoral coarse sediment	0,01	92,3	7,7	0	0
Circalittoral mixed sediment	<0,01	95,2	3	1,8	0
Circalittoral sand	0,01	99,4	0,6	0	0
Circalittoral mud	0,01	31,4	68	0,3	0,4
Offshore circalittoral rock and biogenic reef	<0,01 0	100 8,6	0 0	0 91,4	0 0
Offshore circalittoral coarse sediment	0,01	36,6	62,6	0,8	0
Offshore circalittoral mixed sediment	0,01	88,4	9,5	2,1	0
Offshore circalittoral sand	0,02	99,5	0,5	0	0
Offshore circalittoral mud	0,02	86,6	12,9	0,4	0
Upper bathyal rock and biogenic reef	not in assessment unit
Upper bathyal sediment	0,02	95,2	4,6	0,2	0
Lower bathyal rock and biogenic reef	not in assessment unit
Lower bathyal sediment	not in assessment unit
Abyssal	not in assessment unit

no colours for sealed loss (also not in the assessment sheet) 

The Central North Sea assessment unit (AU) is characterised by the presence of vast areas of offshore circalittoral habitat, with commonly occurring sandy (61% of the AU) and muddy (24% of the AU) substrates and smaller patches of coarse or mixed sediments or rocks. Smaller areas consist of upper bathyal habitats (typically towards the Norwegian Trench) and circalittoral habitat types (typically along the United Kingdom coasts and towards the Southern North Sea).

The assessment of Common Indicator BH2a specifically focuses on eutrophication of benthic habitats in coastal water bodies, including a large share of the circalittoral habitats in the case of the Central North Sea along the United Kingdom coastline. These coastal waters are considered to be almost entirely of high quality or in good status in terms of nutrient enrichment/eutrophication, with few unassessed areas, and regardless of whether assessments are based on invertebrates or vegetation. Minor areas (around 1% of the total assessed) are considered to be in moderate quality status.

In terms of diversity, as assessed with the relative Margalef diversity index (BH2b) the circalittoral and infralittoral waters are not considered to be in a good status. It should be mentioned that these results largely apply to the northern slope of the Dogger Bank and to the Danish EEZ in the south-eastern extension of the Central North Sea, as well as some observations from the most southern part of the United Kingdom coastline. Only the relative diversity of circalittoral muddy habitat is considered high, although sampling predominantly took place in areas with high fishing pressure. The vast areas of offshore habitat seem to be maintaining at least moderate levels of relative diversity.

The expected impacts from physical disturbance due to bottom-contacting fisheries (BH3a) are assessed as high to moderate in offshore circalittoral sandy and muddy habitats, due to observed high fishing pressure levels and, in the case of muddy habitats, the high sensitivity of the habitat type. This might contradict the findings for BH2b that are based on benthic community sampling. It should be noted that benthic community sampling efforts are restricted to certain areas and that it is largely unclear whether these can be considered representative of the entire Central North Sea. It seems that benthic community sampling in offshore circalittoral sandy habitats has taken place mostly in areas with relatively low fishing pressure. For offshore circalittoral habitat types, other than sandy or muddy, the expected impact of physical disturbance due to fisheries is in general considered to be low. For circalittoral coarse and mixed sediment habitats, the expected impact is generally considered lower, but increasing (as grain size decreases) from coarse to muddy sediment types, especially from higher intensity fishery activities.

The results from a pilot assessment of the candidate indicator BH4 indicate that risk of habitat loss is in general non-existent or low, with the exception of biogenic reefs, where the risk of loss in offshore circalittoral and circalittoral areas is in general moderate (which could suggest that these habitats are at risk). Moreover, the exact locations of biogenic reefs are largely unclear and the potentially suitable areas (in the case of low pressure) probably underestimated. Most references are thus made to sea-pen and burrowing megafauna communities, but other types of biogenic reefs can also be expected to be at risk.

The Norwegian Trench

Assessment Unit x Indicator Results x Broad Habitat Types

The Norwegian Trench x Condition of Benthic Habitat Communities: Assessment of some Coastal Habitats in Relation to Nutrient and/or Organic Enrichment (BH2a) 

Coastal water body status:

poor/bad

moderate

high/good

no data

BH existing in AU coastal water bodies

Broadscale habitat type	BH2a invertebrates (< 2009) % of the coastal waterbodies (CWB) area under each quality status	BH2a vegetation (< 2009) % of the coastal waterbodies (CWB) area under each quality status	BH2a invertebrates (2010-2015) % of the coastal waterbodies (CWB) area under each quality status		BH2a vegetation (2010-2015) % of the coastal waterbodies (CWB) area under each quality status
Littoral rock and biogenic reef			not assessed
Littoral sediment			not assessed		not assessed
Infralittoral rock and biogenic reef			not assessed
Infralittoral coarse sediment
Infralittoral mixed sediment
Infralittoral sand
Infralittoral mud
Circalittoral rock and biogenic reef			not assessed
Circalittoral coarse sediment
Circalittoral mixed sediment
Circalittoral sand
Circalittoral mud
Offshore circalittoral rock and biogenic reef			not assessed	not assessed
Offshore circalittoral coarse sediment			not assessed	not assessed
Offshore circalittoral mixed sediment			not assessed	not assessed
Offshore circalittoral sand			not assessed	not assessed
Offshore circalittoral mud			not assessed	not assessed
Upper bathyal rock and biogenic reef			not assessed	not assessed
Upper bathyal sediment			not assessed	not assessed
Lower bathyal rock and biogenic reef	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Lower bathyal sediment	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Abyssal	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU

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The Norwegian Trench x Condition of Benthic Habitat Communities: Margalef diversity in Region II (Greater North Sea) (BH2b)

Relative Margalef diversity (0-1):

Relative high diversity (0,8-1)

Moderate diversity (0,6-0,8)

Relative low diversity (0-0,6)

Uncertain due to very low sample size or not assessed

    ↘       Significant decrease
    ↗       Significant increase
   ↔       No significant changes in relative Margalef diversity
    ?       Unknown: Data for period of concern or period to compare with are lacking

2009-2021 is compared with 1998-2008; 2016-2021 is compared with 2009-2015
In case no data available for 2016-2021: Results for 2009-2015 are presented for 2016-2021, however with lowered confidence level
Data based on grab-core samples; trends extracted from either 'grab-core' samples or 'small core' samples (presented when observed based on one or the other)

Broadscale habitat type	BH2b (2009-2021)	BH2b (2016-2021)
Littoral rock and biogenic reef	Not assessed	Not assessed
Littoral sediment	Not assessed	Not assessed
Infralittoral rock and biogenic reef	Not assessed	Not assessed
Infralittoral coarse sediment	Not assessed	Not assessed
Infralittoral mixed sediment	0,70 ?	0,70 ?
Infralittoral sand	Not assessed	Not assessed
Infralittoral mud	0,45 ?	0,45 ?
Circalittoral rock and biogenic reef	Not assessed	Not assessed
Circalittoral coarse sediment	Not assessed	Not assessed
Circalittoral mixed sediment	0,77 ?	0,77 ?
Circalittoral sand	0,95 ?	0,95 ↔
Circalittoral mud	0,68 ↔	0,55 ↘
Offshore circalittoral rock and biogenic reef	Not assessed	Not assessed
Offshore circalittoral coarse sediment	0,94 ?	0,94 ?
Offshore circalittoral mixed sediment	0,95 ↔	0,84 ↔
Offshore circalittoral sand	0,84 ↔	0,71 ↔
Offshore circalittoral mud	0,63↔	0,60 ↔
Upper bathyal rock and biogenic reef	Not assessed	Not assessed
Upper bathyal sediment	0,74 ?	0,70 ↔
Lower bathyal rock and biogenic reef	Not assessed	Not assessed
Lower bathyal sediment	Not assessed	Not assessed
Abyssal	Not assessed	Not assessed

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The Norwegian Trench x Extent of Physical Disturbance to Benthic Habitats: Fisheries with mobile bottom-contacting gears (BH3a)

Broadscale habitat type	BH3 fisheries abrasion 2009-2020 (% habitat area within assessment unit under each disturbance group)					BH3 fisheries abrasion 2016-2020 (% habitat area within assessment unit under each disturbance group)
	Zero	Low	Moderate	High	Unassessed disturbance	Zero	Low	Moderate	High	Unassessed disturbance
Littoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Littoral sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral rock and biogenic reef	93,32816	3,69579	1,22416	1,75189	0	94,64328	2,66385	0,84376	1,84911	0
Infralittoral coarse sediment	88,64406	6,42692	4,92902	0	0	89,45519	5,59896	4,94584	0	0
Infralittoral mixed sediment	96,26356	0	0,92341	2,81302	0	96,31469	0	0,87229	2,81302	0
Infralittoral sand	26,53937	17,05551	51,88742	4,51770	0	27,38250	16,21238	51,88742	4,51770	0
Infralittoral mud	96,00937	2,88223	0,61481	0,49359	0	96,24558	2,64602	0,71373	0,39466	0
Circalittoral rock and biogenic reef	90,53851	5,25281	2,40999	1,79869	0	91,74340	4,35560	1,79394	2,10706	0
Circalittoral coarse sediment	72,11118	18,56592	9,32290	0	0	74,16239	16,51471	9,32290	0	0
Circalittoral mixed sediment	93,21664	4,32192	0	2,46144	0	93,21664	4,32192	0	2,46144	0
Circalittoral sand	44,46623	18,68454	36,84923	0	0	45,18756	17,96321	36,84923	0	0
Circalittoral mud	91,36022	4,05059	1,00979	3,57941	0	91,84681	3,50691	0,32524	4,32104	0
Offshore circalittoral rock and biogenic reef	89,63716	1,23907	1,20930	0,38944	7,52503	92,25758	1,10147	1,18361	0,43767	5,01967
Offshore circalittoral coarse sediment	73,13105	26,86895	0	0	0	73,67600	26,32400	0	0	0
Offshore circalittoral mixed sediment	38,29647	37,50219	22,28949	1,91185	0	38,62432	39,67160	19,79224	1,91185	0
Offshore circalittoral sand	23,03666	4,96209	72,00125	0	0	24,17434	19,22376	56,60190	0	0
Offshore circalittoral mud	23,25699	6,65900	0,41860	69,66541	0	25,07426	4,78179	1,57076	68,57318	0
Upper bathyal rock and biogenic reef	90,69689	0	0	0	9,30311	94,84235	0	0	0	5,15765
Upper bathyal sediment	51,30264	0	32,68690	16,01046	0	61,03222	0	25,47425	13,49352	0
Lower bathyal rock and biogenic reef	100	0	0	0	0	100	0	0	0	0
Lower bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Abyssal	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed

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The Norwegian Trench x Extent of Physical Disturbance to Benthic Habitats: Aggregate Extraction (BH3b)

Broadscale habitat type	BH3 aggregates extraction 2009-2020 (% habitat area within assessment unit under each disturbance group, note 'Zero' disturbance not assessed)				BH3 aggregates extraction 2016-2020 (% habitat area within assessment unit under each disturbance group, note 'Zero' disturbance not assessed)
	Low	Moderate	High	Unassessed disturbance	Low	Moderate	High	Unassessed disturbance
Littoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Littoral sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral coarse sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral mixed sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral sand	Not assessed	Not assessed	Not assessed	Not assessed	1,12679844	0,690021828	1,988494399	0
Infralittoral mud	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Circalittoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Circalittoral coarse sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Circalittoral mixed sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Circalittoral sand	Not assessed	Not assessed	Not assessed	Not assessed	0,097080332	0,083423408	0,825168168	0
Circalittoral mud	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral coarse sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral mixed sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral sand	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral mud	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Upper bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Upper bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Lower bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Lower bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Abyssal	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed

---

The Norwegian Trench x Pilot Assessment of Area of Habitat Loss (BH4)

Broadscale habitat type	BH4 Sealed loss	BH4 Unsealed loss (by trawling)
	% estimated loss	No loss	% low risk	% moderate risk	% high risk
Littoral rock and biogenic reef	Not assessed
Littoral sediment	Not assessed
Infralittoral rock and biogenic reef	<0,01	100	0	0	0
Infralittoral coarse sediment	0	93,9	4,3	1,8	0
Infralittoral mixed sediment	0	100	0	0	0
Infralittoral sand	0	92,2	7,8	0	0
Infralittoral mud	0	97,1	2,9	0	0
Circalittoral rock and biogenic reef	<0,01	100	0	0	0
Circalittoral coarse sediment	0	94,7	3,5	1,8	0
Circalittoral mixed sediment	0	99,7	0,3	0	0
Circalittoral sand	0	98,6	1,4	0	0
Circalittoral mud	0	93,6	5,3	0,1	1
Offshore circalittoral rock and biogenic reef	<0,01	100	0	0	0
Offshore circalittoral coarse sediment	0	94,5	5,4	0,1	0
Offshore circalittoral mixed sediment	0	98,3	1,7	0	0
Offshore circalittoral sand	0,03	80	20	0	0
Offshore circalittoral mud	<0,01	82,1	17,4	0,6	0
Upper bathyal rock and biogenic reef	<0,01	100	0	0	0
Upper bathyal sediment	0,01	98,9	1,1	0,1	0
Lower bathyal rock and biogenic reef	not assessed (extent < 1km2)
Lower bathyal sediment	not in assessment unit
Abyssal	not in assessment unit

no colours for sealed loss (also not in the assessment sheet) 

The Norwegian Trench assessment unit (AU) comprises a variety of broad-scale habitats from the littoral down to the upper bathyal at around 700 m depth. Most of the AU is in the upper bathyal zone, dominated by upper bathyal muddy sediments. The Norwegian Trench Upper Bathyal Sediments are rated as near-threatened in the Norwegian Red List for Ecosystems and Habitat Types, based on the occurrence of sea-pens and the bamboo coral Isidella lofotensis. Circalittoral rock and biogenic reef (cold-water coral reefs) are found in the western and eastern part of the AU. In the western part (western Norway), these reefs are not exposed to bottom trawling, but accidental contact with longlines and gill nets may cause some degree of damage. The coral reefs in the eastern part of the AU are located inside the Ytre Hvaler National Park that was protected in 2009.

The coastal zone (Water bodies according to the European Union Water Framework Directive (WFD) and other national equivalents of Contracting Parties not part of the EU) of this AU consists of many fjords, some very large, and large archipelagos with numerous islands. For this vast area, only around 40% (benthic invertebrates) and 13% (vegetation) of the total coastal area was assessed. From those, the majority of coastal area results are considered to be in high/good or moderate quality status (WFD status classes). Relative Margalef diversity (BH2b) is found to be moderate to high for those offshore circalittoral and upper bathyal habitats with some benthic community observations available, and low to moderate for infralittoral and circalittoral habitats. Data availability is, however, only considered sufficient to good in terms of representativity for offshore circalittoral and circalittoral mud, respectively. The offshore circalittoral mud is also the habitat type expected to be most impacted by fisheries (almost 70% of habitat expected to be highly impacted) due to expected high sensitivity for physical disturbance in combination with observed high fishing pressure (as indicated by the BH3a indicator). A large part of the infralittoral and offshore circalittoral sandy habitats is expected to be moderately impacted for at least 50%, and circalittoral sand and upper bathyal sediment contain a substantial area expected to be moderately impacted. All other BHTs in the Norwegian Trench are expected to be predominantly low-impacted or not impacted at all as fishing pressure is considered very low. However, fishing pressure there might be underestimated, as VMS data from the Norwegian fleet are not included in the assessments. The pilot assessment of the candidate indicator BH4 shows that sealed loss is local and that risk of unsealed loss
(largely due to fishing activities) is low and rare.

The Kattegat

Assessment Unit x Indicator Results x Broad Habitat Types

The Kattegat x Condition of Benthic Habitat Communities: Assessment of some Coastal Habitats in Relation to Nutrient and/or Organic Enrichment (BH2a) 

Coastal water body status:

poor/bad

moderate

high/good

no data

BH existing in AU coastal water bodies

Broadscale habitat type	BH2a invertebrates (< 2009) % of the coastal waterbodies (CWB) area under each quality status	BH2a vegetation (< 2009) % of the coastal waterbodies (CWB) area under each quality status	BH2a invertebrates (2010-2015) % of the coastal waterbodies (CWB) area under each quality status		BH2a vegetation (2010-2015) % of the coastal waterbodies (CWB) area under each quality status
Littoral rock and biogenic reef			not assessed
Littoral sediment			not assessed		not assessed
Infralittoral rock and biogenic reef			not assessed
Infralittoral coarse sediment
Infralittoral mixed sediment
Infralittoral sand
Infralittoral mud
Circalittoral rock and biogenic reef			not assessed
Circalittoral coarse sediment
Circalittoral mixed sediment
Circalittoral sand
Circalittoral mud
Offshore circalittoral rock and biogenic reef			not assessed	not assessed
Offshore circalittoral coarse sediment			not assessed	not assessed
Offshore circalittoral mixed sediment			not assessed	not assessed
Offshore circalittoral sand			not assessed	not assessed
Offshore circalittoral mud			not assessed	not assessed
Upper bathyal rock and biogenic reef	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Upper bathyal sediment	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Lower bathyal rock and biogenic reef	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Lower bathyal sediment	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Abyssal	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU

---

The Kattegat x Condition of Benthic Habitat Communities: Margalef diversity in Region II (Greater North Sea) (BH2b)

Relative Margalef diversity (0-1):

Relative high diversity (0,8-1)

Moderate diversity (0,6-0,8)

Relative low diversity (0-0,6)

Uncertain due to very low sample size or not assessed

    ↘       Significant decrease
    ↗       Significant increase
   ↔       No significant changes in relative Margalef diversity
    ?       Unknown: Data for period of concern or period to compare with are lacking

2009-2021 is compared with 1998-2008; 2016-2021 is compared with 2009-2015
In case no data available for 2016-2021: Results for 2009-2015 are presented for 2016-2021, however with lowered confidence level
Data based on grab-core samples; trends extracted from either 'grab-core' samples or 'small core' samples (presented when observed based on one or the other)

Broadscale habitat type	BH2b (2009-2021)	BH2b (2016-2021)
Littoral rock and biogenic reef	Not assessed	Not assessed
Littoral sediment	Not assessed	Not assessed
Infralittoral rock and biogenic reef	Not assessed	Not assessed
Infralittoral coarse sediment	0,41 ↘	0,31 ↘
Infralittoral mixed sediment	0,30 ↔	0,28 ↔
Infralittoral sand	0,41 ↘	0,48 ↗
Infralittoral mud	0,18 ↘	0,18 ↔
Circalittoral rock and biogenic reef	Not assessed	Not assessed
Circalittoral coarse sediment	0,77 ↔	0,77 ?
Circalittoral mixed sediment	0,57 ↔	0,55 ↔
Circalittoral sand	0,33 ↘	0,30 ↔
Circalittoral mud	0,62 ↔	0,54 ↘
Offshore circalittoral rock and biogenic reef	Not assessed	Not assessed
Offshore circalittoral coarse sediment	Not assessed	Not assessed
Offshore circalittoral mixed sediment	0,77 ↘	0,66 ↔
Offshore circalittoral sand	1,41 ?	1,41 ?
Offshore circalittoral mud	0,9 ↔	0,78 ↔
Upper bathyal rock and biogenic reef	not in assessment unit	not in assessment unit
Upper bathyal sediment	not in assessment unit	not in assessment unit
Lower bathyal rock and biogenic reef	not in assessment unit	not in assessment unit
Lower bathyal sediment	not in assessment unit	not in assessment unit
Abyssal	not in assessment unit	not in assessment unit

---

The Kattegat x Extent of Physical Disturbance to Benthic Habitats: Fisheries with mobile bottom-contacting gears (BH3a)

Broadscale habitat type	BH3 fisheries abrasion 2009-2020 (% habitat area within assessment unit under each disturbance group)					BH3 fisheries abrasion 2016-2020 (% habitat area within assessment unit under each disturbance group)
	Zero	Low	Moderate	High	Unassessed disturbance	Zero	Low	Moderate	High	Unassessed disturbance
Littoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Littoral sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral rock and	91,34861	4,70597	1,65881	2,28661	0	96,74960	2,28901	0,96140	0
biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral coarse sediment	70,04241	28,54991	1,36226	0,04543	0	78,07087	20,76593	1,16320	0	0
Infralittoral mixed sediment	57,10199	0	41,08656	1,81145	0	70,44020	0	28,54410	1,01570	0
Infralittoral sand	65,79996	30,47800	3,36450	0,35753	0	77,96513	20,66474	1,36608	0,00405	0
Infralittoral mud	64,16936	33,41309	2,41309	0,00445	0	82,53539	15,96292	1,50169	0	0
Circalittoral rock and biogenic reef	99,46978	0	0,49734	0,03288	0	99,51842	0,03288	0,44870	0	0
Circalittoral coarse sediment	34,06456	49,65574	16,27970	0	0	46,08862	38,38547	15,52591	0	0
Circalittoral mixed sediment	43,27921	38,12839	1,92968	16,66272	0	57,31955	27,53379	3,81601	11,33064	0
Circalittoral sand	15,75182	57,54086	24,73781	1,96952	0	31,53203	48,12708	19,74777	0,59313	0
Circalittoral mud	30,20380	16,04477	29,96218	23,78926	0	34,95483	17,73395	27,31654	19,99468	0
Offshore circalittoral rock and biogenic reef	53,46670	0	11,05820	0	35,47510	53,46670	0	11,05820	0	35,47510
Offshore circalittoral coarse sediment	3,76563	68,47307	27,76131	0	0	3,76563	68,47307	27,76131	0	0
Offshore circalittoral mixed sediment	11,45500	67,36027	21,18473	0	0	12,65397	68,27214	19,07390	0	0
Offshore circalittoral sand	18,48653	25,19421	55,52555	0,79371	0	21,89840	24,65494	52,65296	0,79371	0
Offshore circalittoral mud	4,54352	1,41958	0,96943	93,06747	0	4,64135	2,12387	1,50073	91,73405	0
Upper bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Upper bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Lower bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Lower bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Abyssal	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed

---

The Kattegat x Extent of Physical Disturbance to Benthic Habitats: Aggregate Extraction (BH3b)

Broadscale habitat type	BH3 aggregates extraction 2009-2020 (% habitat area within assessment unit under each disturbance group, note 'Zero' disturbance not assessed)				BH3 aggregates extraction 2016-2020 (% habitat area within assessment unit under each disturbance group, note 'Zero' disturbance not assessed)
	Low	Moderate	High	Unassessed disturbance	Low	Moderate	High	Unassessed disturbance
Littoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Littoral sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral coarse sediment	Not assessed	Not assessed	Not assessed	Not assessed	0,277397806	0,011908804	0,054803639	0
Infralittoral mixed sediment	Not assessed	Not assessed	Not assessed	Not assessed	0	0,150839106	0,207144425	0
Infralittoral sand	Not assessed	Not assessed	Not assessed	Not assessed	0,083559223	0,007849755	0,02605415	0
Infralittoral mud	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Circalittoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Circalittoral coarse sediment	Not assessed	Not assessed	Not assessed	Not assessed	0,093393607	0	0	0
Circalittoral mixed sediment	Not assessed	Not assessed	Not assessed	Not assessed	0,093502804	0,001026286	0,001802291	0
Circalittoral sand	Not assessed	Not assessed	Not assessed	Not assessed	0,067481566	0,003535338	0,017595141	0
Circalittoral mud	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral coarse sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral mixed sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral sand	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral mud	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Upper bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Upper bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Lower bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Lower bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Abyssal	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed

---

The Kattegat x Pilot Assessment of Area of Habitat Loss (BH4)

Broadscale habitat type	BH4 Sealed loss	BH4 Unsealed loss (by trawling)
	% estimated loss	No loss	% low risk	% moderate risk	% high risk
Littoral rock and biogenic reef	Not assessed
Littoral sediment	Not assessed
Infralittoral rock and biogenic reef	0 0	100 100	0 0	0 0	0 0
Infralittoral coarse sediment	0	99,7	0,3	0	0
Infralittoral mixed sediment	0	100	0	0	0
Infralittoral sand	0	100	0	0	0
Infralittoral mud	0	87,4	12,6	0	0
Circalittoral rock and biogenic reef	0	100	0	0	0
Circalittoral coarse sediment	0	85,3	14,7	0	0
Circalittoral mixed sediment	0	100	0	0	0
Circalittoral sand	0	100	0	0	0
Circalittoral mud	0	72,1	27,9	0	0
Offshore circalittoral rock and biogenic reef	0	100	0	0	0
Offshore circalittoral coarse sediment	0	15	84,5	0,4	0
Offshore circalittoral mixed sediment	0	99,8	0,2	0	0
Offshore circalittoral sand	0	100	0	0	0
Offshore circalittoral mud	0	78	21,4	0,6	0
Upper bathyal rock and biogenic reef	not in assessment unit
Upper bathyal sediment	not in assessment unit
Lower bathyal rock and biogenic reef	not in assessment unit
Lower bathyal sediment	not in assessment unit
Abyssal	not in assessment unit

no colours for sealed loss (also not in the assessment sheet) 

The Kattegat-Skagerrak is a transitional area between the brackish Baltic waters and the marine waters of the North Sea, resulting in periodic stratifications in the large shallower parts (< 20 m) and more stable and fully marine conditions in the deeper areas. These environmental conditions have a strong impact on the biota in the benthic habitats. The western part of Kattegat is dominated by shallow infralittoral sands, in contrast to the eastern deeper circalittoral muddy parts containing several highly diverse protected offshore banks. The deeper muddy areas around offshore banks are heavily impacted by bottom trawling except for a protected fishing-free zone (since 2009) in the south-eastern part and the Sound (Oeresund), where bottom trawling has been banned since 1932. This high fishing pressure is reflected in the expected high impact on most (93%) of the area of offshore circalittoral mud and moderate to high impact on more than half (54%) of the circalittoral muddy habitat (BH3), reflecting the expected high sensitivity of these broad habitat types (BHT). Substantial parts of several other BHTs (e.g., circalittoral or infralittoral mixed sediment, offshore circalittoral sand) are expected to be moderately to highly impacted as well. Disturbance from aggregate extraction was recorded in 0,067% of the total Kattegat area (not all suitable for this activity), with most habitats of interest exposed to low level of disturbance. It should be noted that there are limitations in the accuracy of the fishing pressure layers provided by the ICES due to the resolution of c-squares in confined areas, in particular in Skagerrak/Kattegat. This issue has been included under the knowledge gaps section of the BH3a indicator. 

Due to the high fishing pressure, there is some (albeit low) risk of partial habitat loss for the indicated muddy habitats, but also for some of the coarse sediment habitats and for the largest part of the offshore circalittoral coarse sediments (pilot assessment BH4). Please note the caveats above regarding fishing pressure data layers.

The various pressure levels (fisheries, nutrient loads and anoxic conditions), combined with ‘natural' or climate-change induced increased variability in low-salinity water inflow from the Baltic, results in observed relatively low diversity levels for most of the infralittoral and circalittoral habitat types (BH2b). Relative diversity seems to be higher (moderate to high) for the offshore circalittoral habitat types.

Regarding nutrient and organic enrichments, the majority of the coastal waters area appears not to be in good quality status, based both on the invertebrate and the vegetation communities, with mainly poor/bad status arising from the vegetation assessment.

The assessment results in the Kattegat have to be treated with caution, since the indicator used to assess the coastal water quality may be sensitive to various pressure types, including physical ones. Besides, the underlying habitat map is of low quality and low resolution for Swedish waters, which also makes the assessment of physical pressures relative. The quality of the habitat map for Swedish waters needs to be improved ahead of the next assessments. Habitat mapping is underway and new data will be available in coming years. However, the low resolution of the underlying habitat map relates to national security and will probably not be improved in the near future.

The Southern North Sea

Assessment Unit x Indicator Results x Broad Habitat Types

Southern North Sea x Condition of Benthic Habitat Communities: Assessment of some Coastal Habitats in Relation to Nutrient and/or Organic Enrichment (BH2a) 

Coastal water body status:

poor/bad

moderate

high/good

no data

BH existing in AU coastal water bodies

Broadscale habitat type	BH2a invertebrates (< 2009) % of the coastal waterbodies (CWB) area under each quality status	BH2a vegetation (< 2009) % of the coastal waterbodies (CWB) area under each quality status	BH2a invertebrates (2010-2015) % of the coastal waterbodies (CWB) area under each quality status		BH2a vegetation (2010-2015) % of the coastal waterbodies (CWB) area under each quality status
Littoral rock and biogenic reef			not assessed
Littoral sediment
Infralittoral rock and biogenic reef			not assessed
Infralittoral coarse sediment
Infralittoral mixed sediment
Infralittoral sand
Infralittoral mud
Circalittoral rock and biogenic reef			not assessed
Circalittoral coarse sediment
Circalittoral mixed sediment
Circalittoral sand
Circalittoral mud
Offshore circalittoral rock and biogenic reef			not assessed	not assessed
Offshore circalittoral coarse sediment			not assessed	not assessed
Offshore circalittoral mixed sediment			not assessed	not assessed
Offshore circalittoral sand			not assessed	not assessed
Offshore circalittoral mud			not assessed	not assessed
Upper bathyal rock and biogenic reef	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Upper bathyal sediment	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Lower bathyal rock and biogenic reef	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Lower bathyal sediment	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Abyssal	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU

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The Kattegat x Condition of Benthic Habitat Communities: Margalef diversity in Region II (Greater North Sea) (BH2b)

Relative Margalef diversity (0-1):

Relative high diversity (0,8-1)

Moderate diversity (0,6-0,8)

Relative low diversity (0-0,6)

Uncertain due to very low sample size or not assessed

    ↘       Significant decrease
    ↗       Significant increase
   ↔       No significant changes in relative Margalef diversity
    ?       Unknown: Data for period of concern or period to compare with are lacking

2009-2021 is compared with 1998-2008; 2016-2021 is compared with 2009-2015
In case no data available for 2016-2021: Results for 2009-2015 are presented for 2016-2021, however with lowered confidence level
Data based on grab-core samples; trends extracted from either 'grab-core' samples or 'small core' samples (presented when observed based on one or the other)

Broadscale habitat type	BH2b (2009-2021)	BH2b (2016-2021)
Littoral rock and biogenic reef	Not assessed	Not assessed
Littoral sediment	Not assessed	Not assessed
Infralittoral rock and biogenic reef	Not assessed	Not assessed
Infralittoral coarse sediment	0,41 ↘	0,31 ↘
Infralittoral mixed sediment	0,30 ↔	0,28 ↔
Infralittoral sand	0,41 ↘	0,48 ↗
Infralittoral mud	0,18 ↘	0,18 ↔
Circalittoral rock and biogenic reef	Not assessed	Not assessed
Circalittoral coarse sediment	0,77 ↔	0,77 ?
Circalittoral mixed sediment	0,57 ↔	0,55 ↔
Circalittoral sand	0,33 ↘	0,30 ↔
Circalittoral mud	0,62 ↔	0,54 ↘
Offshore circalittoral rock and biogenic reef	Not assessed	Not assessed
Offshore circalittoral coarse sediment	Not assessed	Not assessed
Offshore circalittoral mixed sediment	0,77 ↘	0,66 ↔
Offshore circalittoral sand	1,41 ?	1,41 ?
Offshore circalittoral mud	0,9 ↔	0,78 ↔
Upper bathyal rock and biogenic reef	not in assessment unit	not in assessment unit
Upper bathyal sediment	not in assessment unit	not in assessment unit
Lower bathyal rock and biogenic reef	not in assessment unit	not in assessment unit
Lower bathyal sediment	not in assessment unit	not in assessment unit
Abyssal	not in assessment unit	not in assessment unit

---

The Kattegat x Extent of Physical Disturbance to Benthic Habitats: Fisheries with mobile bottom-contacting gears (BH3a)

Broadscale habitat type	BH3 fisheries abrasion 2009-2020 (% habitat area within assessment unit under each disturbance group)					BH3 fisheries abrasion 2016-2020 (% habitat area within assessment unit under each disturbance group)
	Zero	Low	Moderate	High	Unassessed disturbance	Zero	Low	Moderate	High	Unassessed disturbance
Littoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Littoral sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral rock and	91,34861	4,70597	1,65881	2,28661	0	96,74960	2,28901	0,96140	0
biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral coarse sediment	70,04241	28,54991	1,36226	0,04543	0	78,07087	20,76593	1,16320	0	0
Infralittoral mixed sediment	57,10199	0	41,08656	1,81145	0	70,44020	0	28,54410	1,01570	0
Infralittoral sand	65,79996	30,47800	3,36450	0,35753	0	77,96513	20,66474	1,36608	0,00405	0
Infralittoral mud	64,16936	33,41309	2,41309	0,00445	0	82,53539	15,96292	1,50169	0	0
Circalittoral rock and biogenic reef	99,46978	0	0,49734	0,03288	0	99,51842	0,03288	0,44870	0	0
Circalittoral coarse sediment	34,06456	49,65574	16,27970	0	0	46,08862	38,38547	15,52591	0	0
Circalittoral mixed sediment	43,27921	38,12839	1,92968	16,66272	0	57,31955	27,53379	3,81601	11,33064	0
Circalittoral sand	15,75182	57,54086	24,73781	1,96952	0	31,53203	48,12708	19,74777	0,59313	0
Circalittoral mud	30,20380	16,04477	29,96218	23,78926	0	34,95483	17,73395	27,31654	19,99468	0
Offshore circalittoral rock and biogenic reef	53,46670	0	11,05820	0	35,47510	53,46670	0	11,05820	0	35,47510
Offshore circalittoral coarse sediment	3,76563	68,47307	27,76131	0	0	3,76563	68,47307	27,76131	0	0
Offshore circalittoral mixed sediment	11,45500	67,36027	21,18473	0	0	12,65397	68,27214	19,07390	0	0
Offshore circalittoral sand	18,48653	25,19421	55,52555	0,79371	0	21,89840	24,65494	52,65296	0,79371	0
Offshore circalittoral mud	4,54352	1,41958	0,96943	93,06747	0	4,64135	2,12387	1,50073	91,73405	0
Upper bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Upper bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Lower bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Lower bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Abyssal	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed

---

The Kattegat x Extent of Physical Disturbance to Benthic Habitats: Aggregate Extraction (BH3b)

Broadscale habitat type	BH3 aggregates extraction 2009-2020 (% habitat area within assessment unit under each disturbance group, note 'Zero' disturbance not assessed)				BH3 aggregates extraction 2016-2020 (% habitat area within assessment unit under each disturbance group, note 'Zero' disturbance not assessed)
	Low	Moderate	High	Unassessed disturbance	Low	Moderate	High	Unassessed disturbance
Littoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Littoral sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral coarse sediment	Not assessed	Not assessed	Not assessed	Not assessed	0,277397806	0,011908804	0,054803639	0
Infralittoral mixed sediment	Not assessed	Not assessed	Not assessed	Not assessed	0	0,150839106	0,207144425	0
Infralittoral sand	Not assessed	Not assessed	Not assessed	Not assessed	0,083559223	0,007849755	0,02605415	0
Infralittoral mud	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Circalittoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Circalittoral coarse sediment	Not assessed	Not assessed	Not assessed	Not assessed	0,093393607	0	0	0
Circalittoral mixed sediment	Not assessed	Not assessed	Not assessed	Not assessed	0,093502804	0,001026286	0,001802291	0
Circalittoral sand	Not assessed	Not assessed	Not assessed	Not assessed	0,067481566	0,003535338	0,017595141	0
Circalittoral mud	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral coarse sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral mixed sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral sand	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral mud	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Upper bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Upper bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Lower bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Lower bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Abyssal	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed

---

The Kattegat x Pilot Assessment of Area of Habitat Loss (BH4)

Broadscale habitat type	BH4 Sealed loss	BH4 Unsealed loss (by trawling)
	% estimated loss	No loss	% low risk	% moderate risk	% high risk
Littoral rock and biogenic reef	Not assessed
Littoral sediment	Not assessed
Infralittoral rock and biogenic reef	0 0	100 100	0 0	0 0	0 0
Infralittoral coarse sediment	0	99,7	0,3	0	0
Infralittoral mixed sediment	0	100	0	0	0
Infralittoral sand	0	100	0	0	0
Infralittoral mud	0	87,4	12,6	0	0
Circalittoral rock and biogenic reef	0	100	0	0	0
Circalittoral coarse sediment	0	85,3	14,7	0	0
Circalittoral mixed sediment	0	100	0	0	0
Circalittoral sand	0	100	0	0	0
Circalittoral mud	0	72,1	27,9	0	0
Offshore circalittoral rock and biogenic reef	0	100	0	0	0
Offshore circalittoral coarse sediment	0	15	84,5	0,4	0
Offshore circalittoral mixed sediment	0	99,8	0,2	0	0
Offshore circalittoral sand	0	100	0	0	0
Offshore circalittoral mud	0	78	21,4	0,6	0
Upper bathyal rock and biogenic reef	not in assessment unit
Upper bathyal sediment	not in assessment unit
Lower bathyal rock and biogenic reef	not in assessment unit
Lower bathyal sediment	not in assessment unit
Abyssal	not in assessment unit

no colours for sealed loss (also not in the assessment sheet) 

In the Southern North Sea, shallow sandy sediments prevail along the southern and western coasts and on the Dogger Bank. Deeper, offshore circalittoral areas are dominated by sands as well and include larger muddy areas in the central part of the assessment unit. Coarse and mixed sediments are mainly distributed along the English and Danish coasts. The extended littoral zone of the Dutch, German and Danish Wadden Sea represents a unique habitat in the OSPAR Region that is protected as the OSPAR listed threatened and/or declining habitat, “intertidal mudflats”.

Eutrophication in coastal waters is still impacting benthic invertebrates and, even more, macrophytes. Particularly along the Dutch, German and Danish coasts, benthic habitats are not in good status with regard to nutrients or organic enrichment (BH2a). Another major impact, on sublittoral and more offshore habitats, is the widespread disturbance by bottom trawling that covers 93% of the Southern North Sea (BH3a). The greatest proportion of the area (53%) is classified as having moderate disturbance from trawling, while 23% of the area is estimated to be highly disturbed. Trawling disturbance is highest in the offshore mud habitats in the centre of this assessment unit. Offshore circalittoral mud and circalittoral mud are the habitats with the highest trawling disturbance due to high fishing pressure in combination with the expected high sensitivity of these habitats. Likewise, the risk of sediment changes from trawling, potentially leading to habitat loss, is estimated highest for these two habitats (BH4). The Southern North Sea is also a focus area for energy production, with an area of 40 km² (0,02% of the total assessment unit, but which is not all suitable for this activity) sealed by offshore structures. Extraction of sand and gravel is another anthropogenic activity that is carried out to a considerable extent in the Southern North Sea. The extraction of sediment impacts benthic organisms (BH3b) and may lead to habitat loss (BH4).

The overall impact of anthropogenic pressures is reflected in the condition of benthic habitats as assessed with the Margalef diversity index (BH2b). Most assessed habitats have low or moderate relative diversity. Mixed sediments are the only habitats considered to host high relative diversity. However, these habitats comprise only 2% of the assessment area. The predominant sandy habitats as well as coarse sediments are assessed as having low relative diversity.

The Channel

Assessment Unit x Indicator Results x Broad Habitat Types

Channel x Condition of Benthic Habitat Communities: Assessment of some Coastal Habitats in Relation to Nutrient and/or Organic Enrichment (BH2a) 

Coastal water body status:

poor/bad

moderate

high/good

no data

BH existing in AU coastal water bodies

Broadscale habitat type	BH2a invertebrates (< 2009) % of the coastal waterbodies (CWB) area under each quality status	BH2a vegetation (< 2009) % of the coastal waterbodies (CWB) area under each quality status	BH2a invertebrates (2010-2015) % of the coastal waterbodies (CWB) area under each quality status		BH2a vegetation (2010-2015) % of the coastal waterbodies (CWB) area under each quality status
Littoral rock and biogenic reef			not assessed
Littoral sediment
Infralittoral rock and biogenic reef			not assessed
Infralittoral coarse sediment
Infralittoral mixed sediment
Infralittoral sand
Infralittoral mud
Circalittoral rock and biogenic reef			not assessed
Circalittoral coarse sediment
Circalittoral mixed sediment
Circalittoral sand
Circalittoral mud
Offshore circalittoral rock and biogenic reef			not assessed	not assessed
Offshore circalittoral coarse sediment			not assessed	not assessed
Offshore circalittoral mixed sediment			not assessed	not assessed
Offshore circalittoral sand			not assessed	not assessed
Offshore circalittoral mud			not assessed	not assessed
Upper bathyal rock and biogenic reef	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Upper bathyal sediment	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Lower bathyal rock and biogenic reef	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Lower bathyal sediment	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Abyssal	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU

---

Channel x Condition of Benthic Habitat Communities: Margalef diversity in Region II (Greater North Sea) (BH2b)

Relative Margalef diversity (0-1):

Relative high diversity (0,8-1)

Moderate diversity (0,6-0,8)

Relative low diversity (0-0,6)

Uncertain due to very low sample size or not assessed

    ↘       Significant decrease
    ↗       Significant increase
   ↔       No significant changes in relative Margalef diversity
    ?       Unknown: Data for period of concern or period to compare with are lacking

2009-2021 is compared with 1998-2008; 2016-2021 is compared with 2009-2015
In case no data available for 2016-2021: Results for 2009-2015 are presented for 2016-2021, however with lowered confidence level
Data based on grab-core samples; trends extracted from either 'grab-core' samples or 'small core' samples (presented when observed based on one or the other)

Broadscale habitat type	BH2b (2009-2021)	BH2b (2016-2021)
Littoral rock and biogenic reef	Not assessed	Not assessed
Littoral sediment	Not assessed	Not assessed
Infralittoral rock and biogenic reef	Not assessed	Not assessed
Infralittoral coarse sediment	0,75 ?	0,75 ?
Infralittoral mixed sediment	0,67 ?	0,67 ?
Infralittoral sand	0,53 ?	0,53 ?
Infralittoral mud	0,69 ?	0,69 ?
Circalittoral rock and biogenic reef	Not assessed	Not assessed
Circalittoral coarse sediment	0,63 ?	0,63 ?
Circalittoral mixed sediment	0,98 ?	0,98 ?
Circalittoral sand	0,45 ↘	0,45 ?
Circalittoral mud	0,84 ?	0,84 ?
Offshore circalittoral rock and biogenic reef	Not assessed	Not assessed
Offshore circalittoral coarse sediment	0,60 ?	0,60 ?
Offshore circalittoral mixed sediment	0,79 ?	0,79 ?
Offshore circalittoral sand	0,42 ?	0,42 ?
Offshore circalittoral mud	Not assessed	Not assessed
Upper bathyal rock and biogenic reef	not in assessment unit	not in assessment unit
Upper bathyal sediment	not in assessment unit	not in assessment unit
Lower bathyal rock and biogenic reef	not in assessment unit	not in assessment unit
Lower bathyal sediment	not in assessment unit	not in assessment unit
Abyssal	not in assessment unit	not in assessment unit

---

Channel x Extent of Physical Disturbance to Benthic Habitats: Fisheries with mobile bottom-contacting gears (BH3a)

Broadscale habitat type	BH3 fisheries abrasion 2009-2020 (% habitat area within assessment unit under each disturbance group)					BH3 fisheries abrasion 2016-2020 (% habitat area within assessment unit under each disturbance group)
	Zero	Low	Moderate	High	Unassessed disturbance	Zero	Low	Moderate	High	Unassessed disturbance
Littoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Littoral sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral rock and biogenic reef	23,98771	48,00397	7,3715	20,63681	0	26,57938	47,69986	10,01526	15,70551	0
Infralittoral coarse sediment	7,74143	61,8708	30,38773	0	0,00004	8,3101	62,72884	28,96102	0	0,00004
Infralittoral mixed sediment	49,91663	10,83163	32,94909	6,29999	0,00267	55,92899	10,34467	29,19551	4,52816	0,00267
Infralittoral sand	16,5269	19,73665	43,77056	19,96588	0	16,70395	24,92936	47,58889	10,77781	0
Infralittoral mud	18,38481	14,37686	39,15195	28,08638	0	18,38481	16,17589	48,02553	17,41377	0
Circalittoral rock and biogenic reef	14,79773	49,43333	13,85382	21,91513	0	23,50229	46,39783	19,45067	10,64921	0
Circalittoral coarse sediment	6,75774	36,43777	56,80448	0	0	13,3695	39,58136	47,04914	0	0
Circalittoral mixed sediment	18,76193	34,17799	12,84525	34,21482	0	32,31307	27,46659	14,07531	26,14504	0
Circalittoral sand	5,20591	14,392	78,71626	1,68583	0	5,3677	19,27876	74,11338	1,24016	0
Circalittoral mud	4,96233	14,40771	54,10376	26,52621	0	4,96233	13,43613	62,17115	19,4304	0
Offshore circalittoral rock and biogenic reef	0,18137	51,27294	5,26557	34,53881	8,74131	3,84209	51,95751	7,03513	28,4274	8,73787
Offshore circalittoral coarse sediment	0,26196	95,69143	3,99438	0,05223	0	1,03842	95,4457	3,46364	0,05223	0
Offshore circalittoral mixed sediment	0,17415	80,54583	0,31948	18,96054	0	2,16913	78,55729	0,40599	18,86759	0
Offshore circalittoral sand	0,00001	1,26315	88,13573	10,60111	0	0,00001	3,44767	86,53036	10,02196	0
Offshore circalittoral mud	0,02262	0,43961	0	99,53777	0	0,02262	0,29066	4,65392	95,0328	0
Upper bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Upper bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Lower bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Lower bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Abyssal	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed

---

Channel x Extent of Physical Disturbance to Benthic Habitats: Aggregate Extraction (BH3b)

Broadscale habitat type	BH3 aggregates extraction 2009-2020 (% habitat area within assessment unit under each disturbance group, note 'Zero' disturbance not assessed)				BH3 aggregates extraction 2016-2020 (% habitat area within assessment unit under each disturbance group, note 'Zero' disturbance not assessed)
	Low	Moderate	High	Unassessed disturbance	Low	Moderate	High	Unassessed disturbance
Littoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Littoral sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral coarse sediment	0,000281728	0,000135411	0,000542239	0	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral mixed sediment	Not assessed	Not assessed	Not assessed	Not assessed	0	0,150839106	0,207144425	0
Infralittoral sand	Not assessed	Not assessed	Not assessed	Not assessed	0,083559223	0,007849755	0,02605415	0
Infralittoral mud	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Circalittoral rock and biogenic reef	0,000014507	0,008725148	0,017078387	0	0	0,005846362	0,008725288	0
Circalittoral coarse sediment	0,211351886	0,03722331	0,275503459	0	0,102670147	0,017414741	0,134361187	0
Circalittoral mixed sediment	0	0,048314286	0,019983608	0	0	0,000252443	0	0
Circalittoral sand	0,001609139	0,000323068	0,008327262	0	0,002380437	0,000526395	0,006964956	0
Circalittoral mud	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral rock and biogenic reef	0,000000283	0	0	0	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral coarse sediment	0,032016412	0,005768335	0,063586644	0	0,028104226	0,005642615	0,041614329	0
Offshore circalittoral mixed sediment	0,000057076	0	0	0	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral sand	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral mud	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Upper bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Upper bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Lower bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Lower bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Abyssal	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed

---

Channel x Pilot Assessment of Area of Habitat Loss (BH4)

Broadscale habitat type	BH4 Sealed loss	BH4 Unsealed loss (by trawling)
	% estimated loss	No loss	% low risk	% moderate risk	% high risk
Littoral rock and biogenic reef	Not assessed
Littoral sediment	Not assessed
Infralittoral rock and biogenic reef	0 0	100 0,9	0 0	0 82,9	0 16,2
Infralittoral coarse sediment	0	97,2	0,4	2,5	0
Infralittoral mixed sediment	0	100	0	0	0
Infralittoral sand	0	99,1	0,9	0	0
Infralittoral mud	0	20,6	64,2	0,9	14,3
Circalittoral rock and biogenic reef	0 0	100 97,2	0 0	0 1,9	0 0,9
Circalittoral coarse sediment	<0,01	87,8	4,1	8	0
Circalittoral mixed sediment	0	100	0	0	0
Circalittoral sand	0	92,7	7,3	0	0
Circalittoral mud	0	8,7	72,3	7,9	11,1
Offshore circalittoral rock and biogenic reef	0	100	0	0	0
Offshore circalittoral coarse sediment	0	82	13,4	4,6	0
Offshore circalittoral mixed sediment	0	93	7	0	0
Offshore circalittoral sand	0	92,5	7,5	0	0
Offshore circalittoral mud	0	9,3	69,3	6	15,4
Upper bathyal rock and biogenic reef	not in assessment unit
Upper bathyal sediment	not in assessment unit
Lower bathyal rock and biogenic reef	not in assessment unit
Lower bathyal sediment	not in assessment unit
Abyssal	not in assessment unit

no colours for sealed loss (also not in the assessment sheet) 

In the Channel, the total assessed area for coastal waters quality (BH2a) changed significantly between the two available reporting cycles: from 43,4% (invertebrates) and 0,02% (vegetation) to respectively 83,2% and 49,0% of the total area of coastal water bodies in this assessment unit (AU). During the assessment period 2010-2015, 83,2% of the total area of coastal water bodies in the AU was assessed as in high or good quality status based on benthic invertebrate compositions, while no data were available for the remaining area. Quality status as based on benthic vegetation was assessed to be high or good for 31,1%, moderate for 16,9% (The Solent, the eastern part of the Normano-Breton Gulf) and poor or bad status for 1,0% (western part of the Bay of Seine) of the total area of coastal water bodies. Data were, however, lacking for more than half (51,0%) of the coastal water bodies area.
Diversity assessed with the relative Margalef diversity index (BH2b) was low or moderate in the infralittoral habitats and several of the circalittoral habitats. Only in the circalittoral mixed sediment and in the circalittoral mud habitats was relative diversity assessed as high, although the monitoring and assessment was limited to a small proportion of the total habitat area.

Most of the Channel was assessed as disturbed by trawling (BH3a) mostly at moderate or low levels during the 2009-2020 assessment period. The greatest disturbance was observed in offshore circalittoral mud, with 99,53% of the area under high disturbance, although it should be noted that this habitat covered <1% of the Channel, so that the high disturbance extended to discrete areas only. More than 50% of the area of infralittoral coarse sediment, offshore circalittoral rock, biogenic reef, offshore circalittoral coarse sediment and offshore circalittoral mixed sediment were assessed as under low disturbance. The infralittoral mixed sediment has the largest area expected to be without disturbance (49,9%). In the 2016-2020 assessment period, the disturbance patterns were very similar, but the areas expected to be without impact were larger. This is because the 2009-2020 QSR assessment interval provided more years of VMS data overall, and therefore presented an increased likelihood of disturbance compared to the 2016-2020 period. The most disturbed areas were the south-east of the Isle of Wight as well as the coastal regions of England and France. The area without disturbance was situated to the west of the Isle of Wight, and there was lower disturbance around Guernsey, Jersey and the coast of Normandy by comparison with the rest of the Channel. The Channel has the highest proportion of total disturbed area within an assessment unit due to aggregate extraction (BH3b) compared with other assessment units, with the greatest disturbance occurring on the south coast of England. It should be noted that only aggregate extraction data available from United Kingdom and Danish waters were used for the disturbance calculations. Other countries, for example Germany, the Netherlands and Belgium, have extraction activity, but the footprint data required for a detailed analysis of disturbance, were not available at the time of assessment. Therefore, comparisons between assessment units were the result of data availability. The most affected habitat was circalittoral coarse sediment, with the highest proportion of high disturbance (0,3%).

The risk of sediment changes leading to habitat loss (BH4) is estimated as low for most of the habitat types assessed. The highest risk was assessed for circalittoral mud, offshore circalittoral mud, infralittoral mud and infralittoral biogenic reef and ranged from 11% to 16%.

Assessment of the status of OSPAR listed threatened and/or declining habitats in the Greater North Sea

Maerl beds were assessed as being in poor status, while recognising that there was a lot of uncertainty in the assessment and gaps in the data. However, compared with the last assessment in 2010, when this habitat type was simply assessed as occurring in the Region but not as threatened and/or declining, the latest assessment points towards a deteriorating status.

The European flat oyster Ostrea edulis is native to the North-East Atlantic and occurs in intertidal and subtidal habitats from Norway to Morocco and has historically covered extensive offshore areas. For the Greater North Sea, it was not possible to conclusively determine the status of Ostrea edulis beds since they have been severely depleted. Some remnant populations occur in waters around the United Kingdom, France, the Netherlands and Denmark, whereas the oysters are considered functionally extinct in German and Belgian waters. Remnant oyster beds are generally supported by extensive reintroduction and restoration efforts.

Intertidal mussel beds were assessed to have improved compared with 2009 in the Dutch and German Wadden Sea, due to the management actions in those habitats, but show (local) declines in other areas, such as Scotland and Sweden.
Compared with the last report from 2009, the status of intertidal mudflats remains poor. While the geographical distribution and extent of the habitat is generally good in the Greater North Sea (stable) the condition of intertidal mudflats is poor due to anthropogenic pressures including climate change, nutrient enrichment, invasive species and hydrological changes (e.g., construction).

Sea-pen and burrowing megafauna habitats occur at productive muddy seafloor sites and there has been no indication of improved status. Towed, bottom-contacting fishing gear continues to be the most significant pressure, the use of which was assessed as increasing in the Greater North Sea. This pressure is assessed to have resulted from the absence of sensitive and large-bodied sea-pen species in muddy sediment habitats which would otherwise be suitable for them, for example the Fladen grounds between Scotland and Norway. Smaller-bodied sea-pens and burrowing crustaceans were found to be less sensitive to the pressure.

There are significant differences within the Greater North Sea Region in the health of eelgrass beds (Zostera beds). In some locations, the historically significant declines in distribution and extent are continuing. However, in southern parts of the Region, and in the waters of Denmark, the Netherlands and France, there might be a stable or slightly increasing trend when viewed over the past 10-year period. The condition of Zostera beds is notoriously complex to assess, and future work could focus on assessing ecosystem functions such as habitat provision and carbon sequestration as well as the density of the seagrass beds. The regeneration of Zostera beds takes place over much longer time scales than do reductions in coverage, and therefore it is more important to avoid further damage and loss than to rely on habitat restoration.

The status of coral gardens is assessed as continuing to be in poor status due to the habitat’s slow recovery rate. However, the assessment shows that for this habitat the pressure from fisheries has been decreasing recently.

Table S.4: Summary results of the assessment of the OSPAR threatened and /or declining habitats in the Greater North Sea

Greater North Sea	Maerl beds	Flat oyster and Ostrea edulis beds	Intertidal Mytilus edulis beds on mixed and sandy sediments	Intertidal mudflats	Zostera beds	Sea-pen and burrowing megafauna	Deep-sea sponge aggregations	Coral gardens	Lophelia pertusa reefs
Distribution	?	?		↔	North ↓ Rest ↔ ?	↔	↔	↔	↔
Extent	?	?		↔	North ↓ Rest ↔ ?	↔	?	?	↔
Condition	?	?		↔	↓ ↔ ?	↔	↓	↓	↔
Previous OSPAR status assessment	○	●	●	●	●	●	●	●	●
Status (overall assessment)	poor	?	poor	poor	poor	poor	poor	poor	poor

Legend:

Previous status assessment:
Regions where species occurs (○) and has been recognised by OSPAR to be threatened and/or declining (●)

Trends in status (since the assessment in the background document):

↓	decreasing trend or deterioration of the criterion assessed
↑	increasing trend or improvement in the criterion assessed
↔	no change observed in the criterion assessed
	chaos symbol demonstrating that the available information is pointing in all directions within the specific region
?	trend unknown in the criterion assessed
N/A	not applicable (i.e. species not present during breeding or non-breeding season)

Status of criterion assessed:

Celtic Seas - Shelf edge benthic habitats

Two assessment units with indicator results: BH2a, BH3a and BH3b
The Celtic Seas (Region III) are home to a rich and diverse range of species and habitats. Warm southern waters mix with cold northern waters, resulting in high levels of productivity and a food-rich environment. The Celtic Seas Region contains a rich variety of physical habitats and associated species, ranging from shallow inshore reefs and sandbanks to canyons, seamounts, and cold-water coral reef in deeper waters. Deep-water habitats host slow-growing species which are highly sensitive to physical disturbance. Indicators BH2a and BH3a and BH3b were analysed for the Northern and Southern Celtic Sea assessment units.

The benthic vegetation and benthic invertebrates of coastal water bodies assessed (respectively 68% and 75% of the total area) in the Northern Celtic seas were in high/good status. In the Southern Celtic Sea, most of the total area of water bodies was not assessed (respectively 99,1 and 59,9% for invertebrates and vegetation), thus compromising any conclusion at this scale.

For the period 2009-2020, less than half of the Northern Celtic Sea was assessed as disturbed by bottom-contacting fisheries. Fishing disturbance in the Southern Celtic Seas was much higher, at more than 70% of the area. The broad habitat types that were most disturbed in both assessment units were offshore circalittoral mud and upper bathyal sediment. Disturbance from aggregate extraction was low in both areas (<0,01% of total area).

The level of confidence for the assessment for the Celtic Seas is considered medium

• Level of evidence: medium. The assessment is based on multiple lines of evidence, but gaps were observed in the spatial coverage of the biological information available. 
• Degree of agreement: medium. The indicators and status assessments of OSPAR listed habitats results mostly agree.
   

The Northern Celtic Sea

Assessment Unit x Indicator Results x Broad Habitat Types

Northern Celtic Sea x Condition of Benthic Habitat Communities: Assessment of some Coastal Habitats in Relation to Nutrient and/or Organic Enrichment (BH2a) 

Coastal water body status:

poor/bad

moderate

high/good

no data

BH existing in AU coastal water bodies

Broadscale habitat type	BH2a invertebrates (< 2009) % of the coastal waterbodies (CWB) area under each quality status	BH2a vegetation (< 2009) % of the coastal waterbodies (CWB) area under each quality status	BH2a invertebrates (2010-2015) % of the coastal waterbodies (CWB) area under each quality status		BH2a vegetation (2010-2015) % of the coastal waterbodies (CWB) area under each quality status
Littoral rock and biogenic reef			not assessed
Littoral sediment
Infralittoral rock and biogenic reef			not assessed		not assessed
Infralittoral coarse sediment					not assessed
Infralittoral mixed sediment					not assessed
Infralittoral sand					not assessed
Infralittoral mud					not assessed
Circalittoral rock and biogenic reef			not assessed		not assessed
Circalittoral coarse sediment					not assessed
Circalittoral mixed sediment					not assessed
Circalittoral sand					not assessed
Circalittoral mud			not assessed		not assessed
Offshore circalittoral rock and biogenic reef			not assessed		not assessed
Offshore circalittoral coarse sediment			not assessed		not assessed
Offshore circalittoral mixed sediment			not assessed		not assessed
Offshore circalittoral sand			not assessed		not assessed
Offshore circalittoral mud			not assessed		not assessed
Upper bathyal rock and biogenic reef	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Upper bathyal sediment	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Lower bathyal rock and biogenic reef	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Lower bathyal sediment	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU
Abyssal	not existing in CWB of AU	not existing in CWB of AU	not existing in CWB of AU		not existing in CWB of AU

---

Northern Celtic Sea x Extent of Physical Disturbance to Benthic Habitats: Fisheries with mobile bottom-contacting gears (BH3a)

Broadscale habitat type	BH3 fisheries abrasion 2009-2020 (% habitat area within assessment unit under each disturbance group)					BH3 fisheries abrasion 2016-2020 (% habitat area within assessment unit under each disturbance group)
	Zero	Low	Moderate	High	Unassessed disturbance	Zero	Low	Moderate	High	Unassessed disturbance
Littoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Littoral sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral rock and biogenic reef	52,86865	25,93789	14,58171	5,91158	0,70018	62,48645	19,87419	12,12371	4,88565	0,62999
Infralittoral coarse sediment	43,24217	48,41485	8,18813	0,12857	0,02628	53,89958	40,3138	5,6453	0,11504	0,02628
Infralittoral mixed sediment	49,8022	0,80093	44,4452	4,95168	0	58,77606	0,45205	36,62227	4,14962	0
Infralittoral sand	41,80592	50,62807	5,31962	2,24638	0	52,0108	42,53423	4,56496	0,89001	0
Infralittoral mud	45,37756	46,4009	6,61832	1,60322	0	51,40957	45,31537	2,72357	0,5515	0
Circalittoral rock and biogenic reef	41,15439	35,64755	16,15986	7,0382	0	52,85346	27,48449	14,55997	5,10208	0
Circalittoral coarse sediment	22,36018	62,64526	14,89828	0,09628	0	38,18118	52,05777	9,72339	0,03765	0
Circalittoral mixed sediment	14,45473	54,08665	18,7578	12,70082	0	29,51746	43,49444	19,90725	7,08085	0
Circalittoral sand	20,90185	71,05795	7,86634	0,17347	0,0004	30,91771	63,03129	6,0152	0,0358	0
Circalittoral mud	12,22665	44,03587	18,89354	24,84395	0	21,63074	43,88883	17,71156	16,76886	0
Offshore circalittoral rock and biogenic reef	27,7404	27,57632	5,2874	2,40595	36,98994	41,13492	19,50444	5,29266	1,51634	32,55165
Offshore circalittoral coarse sediment	13,2532	85,41155	1,26613	0,06913	0	24,22623	74,87492	0,85216	0,04668	0
Offshore circalittoral mixed sediment	11,33835	78,8059	8,45607	1,39968	0	24,27318	67,35491	6,85746	1,51445	0
Offshore circalittoral sand	6,59166	32,46388	60,052	0,89246	0	14,27355	33,76194	51,32544	0,63907	0
Offshore circalittoral mud	1,46958	14,9644	5,14912	78,4169	0	4,95939	15,8841	9,42932	69,72719	0
Upper bathyal rock and biogenic reef	46,48044	0	1,05281	0,14068	52,32607	84,82189	0	0,01298	0,14068	15,02446
Upper bathyal sediment	34,61663	0,00006	23,82584	41,55531	0,00216	46,35581	0,00006	19,9	33,74309	0,00105
Lower bathyal rock and biogenic reef	74,63526	0	7,96703	0	17,39772	98,57356	0	0,96471	0	0,46173
Lower bathyal sediment	91,03495	0	8,51833	0,44672	0	96,82943	0	3,12086	0,0497	0
Abyssal	96,27191	0	3,60435	0,11563	0,00811	97,41281	0	2,4634	0,11568	0,00811

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Northern Celtic Sea x Extent of Physical Disturbance to Benthic Habitats: Aggregate Extraction (BH3b)

Broadscale habitat type	BH3 aggregates extraction 2009-2020 (% habitat area within assessment unit under each disturbance group, note 'Zero' disturbance not assessed)				BH3 aggregates extraction 2016-2020 (% habitat area within assessment unit under each disturbance group, note 'Zero' disturbance not assessed)
	Low	Moderate	High	Unassessed disturbance	Low	Moderate	High	Unassessed disturbance
Littoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Littoral sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral coarse sediment	0,0004895	0	0,0021713	0	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral mixed sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral sand	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Infralittoral mud	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Circalittoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Circalittoral coarse sediment	0,0076748	0,0007801	0,0099448	0	0,0081987	0,0007587	0,0053462	0
Circalittoral mixed sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Circalittoral sand	0,0055543	0,0007563	0,000344	0	Not assessed	Not assessed	Not assessed	Not assessed
Circalittoral mud	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral coarse sediment	0,0022349	0,0003176	0,0016345	0	0,0006004	0,00006567	0,0007808	0
Offshore circalittoral mixed sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral sand	0,0022002	0,000295	0,0008384	0	Not assessed	Not assessed	Not assessed	Not assessed
Offshore circalittoral mud	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Upper bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Upper bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Lower bathyal rock and biogenic reef	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Lower bathyal sediment	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed
Abyssal	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed	Not assessed