Red List habitat classification > RL - Marine habitats > RLNEA - Atlantic > NEAA5.26 Atlantic upper circalittoral muddy sand

Atlantic upper circalittoral muddy sand

Quick facts

Red List habitat type code NEAA5.26
Threat status
Europe Endangered
EU Endangered
Relation to
Source European Red List habitat factsheet
European Red List of habitats reports
European Red List of habitats (Excel table)

Summary

This habitat comprises circalittoral non-cohesive muddy sands with the silt content of the substratum typically ranging from 5% to 20%. It is generally found in water depths of over 15-20 m. These circalittoral habitats tend to be more stable than their infralittoral counterparts and as such support a richer infaunal community. This habitat supports animal-dominated communities characterised by a wide variety of polychaetes, bivalves and echinoderms.

Indicators of quality:

Both biotic and abiotic indicators have been used to describe marine habitat quality. These include: the presence of characteristic species as well as those which are sensitive to the pressures the habitat may face; water quality parameters; levels of exposure to particular pressure, and more integrated indices which describe habitat structure and function, such as trophic index, or successional stages of development in habitats that have a natural cycle of change over time.

There are no commonly agreed indicators of quality for this habitat, although particular parameters may have been set in certain situations e.g. protected features within Natura 2000 sites, where reference values have been determined and applied on a location-specific basis.

Characteristic species
For full habitat description, please download the habitat factsheet.

Threat status

Synthesis of Red List assessment

This habitat is relatively common and has a considerable natural range in the North East Atlantic although a patchy distribution.
Most sedimentary benthic systems on the continental shelf of Europe are believed to have been modified by fishing activities in the last 100 years, particularly by mobile demersal gears, and this habitat remains under fishing pressure. Data from a single year, 2013/2014, has revealed that than 40% of circalittoral fine sands and muddy sand were subject to trawling fishing pressure in the North Sea, with over 10% of this being interpreted a high or moderate pressure. When combining data for the North Sea and Celtic Sea more than 80% of this habitat type is considered to have been subject to such fishing pressure. Given that this is based on a single year of data, and that this type of pressure has been taking place for decades, it is likely to be an underestimate of the total area of this habitat which has been subject to such pressure. Disturbance of the substratum due to intensive fishing activities using bottom trawls or dredges can damage or modify infaunal communities, with burrowing echinoderms and bivalves being particularly vulnerable and therefore affect habitat quality.
Expert opinion is that there has been a very substantial reduction in quality of this habitat, most likely an intermediate decline affecting more than 80% of its extent although it is clear that in some locations there has also been a severe decline. The severity will depend on factors such as the intensity and frequency of disturbance. This habitat has therefore been assessed as Endangered for both the EU 28 and EU 28+ because of both past and likely continuing declines in quality.
EU
Red List Category Red List Criteria
Endangered C/D1
Europe
Red List Category Red List Criteria
Endangered C/D1

Confidence in the assessment

low
Red List of habitat categories and criteria descriptions

Pressures and threats

  • Biological resource use other than agriculture & forestry
    • Fishing and harvesting aquatic resources
    • Professional active fishing
    • Benthic or demersal trawling
    • Benthic dredging
  • Pollution
    • Marine water pollution
    • Toxic chemical discharge from material dumped at sea
    • Synthetic compound contamination
  • Climate change
    • Changes in abiotic conditions
    • Water flow changes (limnic, tidal and oceanic)
    • Wave exposure changes

Habitat restoration potential

This habitat is naturally subject to disturbance therefore likely to recover character and functionality relatively quickly if the substrate and hydrographic conditions are the same. For example meta-analysis of data on fishing impacts on muddy sand communities indicate that the recovery of biota can be measured in years.

Trends in extent

Average current trend in quantity

Unknown Unknown
EU28 EU28+

Trends in quality

Average current trend in quality

Decreasing Decreasing
EU28 EU28+

Conservation and management needs

Beneficial management measures for this habitat include the regulation of fishing activity which damage or disturb seabed communities including through the establishment of marine protected areas. Additionally, appropriate regulation and control of chemical discharges from outfalls to reduce the levels entering into, and being retained by, muddy sediments.

List of conservation and management needs

  • Measures related to marine habitats
    • Other marine-related measures
  • Measures related to spatial planning
    • Establish protected areas/sites
  • Measures related to hunting, taking and fishing and species management
    • Regulation/Management of fishery in marine and brackish systems
  • Measures related to urban areas, industry, energy and transport
    • Urban and industrial waste management

Distribution

For each habitat a distribution map was produced from a wide variety of sources indicating known and potential occurrences of the habitat in 10x10 km grids within Europe. Occurrences in grid cells were given in two classes: actual distribution from relatively reliable sources (surveys, expert knowledge), and potential distribution based on models or less reliable indicators. Please download the fact sheet to see the map.

Geographic occurrence and trends

Seas Present or presence uncertain Current area of habitat (Km2) Recent trend in quantity (last 50 years) Recent trend in quality (last 50 years)
Bay of Biscay and the Iberian Coast Present Unknown Decreasing Unknown
Celtic Seas
Greater North Sea
Kattegat
Macaronesia

Extent of Occurrence, Area of Occupancy and habitat area

Extent of Occurrence (EOO) (Km2) Area of Occupancy (AOO) Current estimated Total Area Comment
EU28 3,496,903 500 >2,853 The area estimate for this habitat has been derived from a synthesis of EUNIS seabed habitat geospatial information for the European Seas but is recognised as being an underestimate.
EU28+ >500 >2,853 EOO and AOO have been calculated on the available data. Although this data set is known to be incomplete the figures exceed the thresholds for threatened status.
AOO = the area occupied by a habitat measured in number of 10x10 km grid cells.
EOO = the area (km2) of the envelope around all occurrences of a habitat (calculated by a minimum convex polygon).

Characteristic species

The full list of characteristic species and genus are available above from the Summary. The species available in the EUNIS database are shown here.
Invertebrates Abra alba
Invertebrates Asterias rubens
Invertebrates Astropecten irregularis
Invertebrates Chaetozone gibber
Invertebrates Harpinia antennaria
Invertebrates Myriochele danielsseni
Invertebrates Nephtys hombergii
Invertebrates Nucula nitidosa
Invertebrates Pagurus bernhardus
Invertebrates Paradoneis ilvana
Invertebrates Pectinaria koreni
Invertebrates Phyllodoce rosea
Invertebrates Prionospio fallax
Invertebrates Scoloplos armiger
Invertebrates Spiophanes bombyx
Invertebrates Spiophanes kroyeri
Species scientific name English common name Species group
Abra alba Invertebrates
Asterias rubens Invertebrates
Astropecten irregularis Invertebrates
Chaetozone gibber Invertebrates
Harpinia antennaria Invertebrates
Myriochele danielsseni Invertebrates
Nephtys hombergii Invertebrates
Nucula nitidosa Invertebrates
Pagurus bernhardus Invertebrates
Paradoneis ilvana Invertebrates
Pectinaria koreni Invertebrates
Phyllodoce rosea Invertebrates
Prionospio fallax Invertebrates
Scoloplos armiger Invertebrates
Spiophanes bombyx Invertebrates
Spiophanes kroyeri Invertebrates

Vegetation types

Relation to vegetation types (syntaxa)

Not available

Other classifications

Not available
European Environment Agency (EEA)
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1050 Copenhagen K
Denmark
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