Faunal communities in marine Atlantic infralittoral coarse sediment
Quick facts
| Red List habitat type | code NEAA5.13 |
|---|---|
| Threat status | |
| Europe | Vulnerable |
| EU | Vulnerable |
| Relation to |
|
| Source | European Red List habitat factsheet |
| European Red List of habitats reports | |
| European Red List of habitats (Excel table) |
Summary
This is a moderately exposed habitat with coarse sand, gravelly sand, shingle and gravel in the infralittoral, subject to disturbance by tidal steams and wave action. Such habitats found on the open coast or in tide-swept marine inlets. The faunal communities can be very abundant. In the case of the Dutch Borkum Reef Ground, for example, Lanice conchilega beds with estimated densities of >1500 individuals/m2 have been recorded.
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 has a large natural range in the North East Atlantic. A combination of survey data and modelling indicates that it does not have a restricted geographical distribution nor occur in only a few locations in the North East Atlantic and therefore qualifies as Least Concern under criterion B.
Most sedimentary benthic systems on the continental shelf of Europe have been modified by fishing activities, particularly bottom trawls and dredging, in the last 100 years and this habitat remains under fishing pressure and subject to aggregate extraction. Data for 2013/2014 has revealed that more than 70% of this habitat in the North Sea and Celtic Sea was subject to fishing pressure by bottom otter, beam and mid-water trawls. Coarse sediment communities have greater resilience and faster recovery rates that those in fine sediments but 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.
Expert opinion is that there has been a substantial reduction in quality of this habitat, most likely an intermediate decline affecting more than 50% 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 Vulnerable for both the EU 28 and EU 28+ because of both past and likely continuing declines in quality.
Most sedimentary benthic systems on the continental shelf of Europe have been modified by fishing activities, particularly bottom trawls and dredging, in the last 100 years and this habitat remains under fishing pressure and subject to aggregate extraction. Data for 2013/2014 has revealed that more than 70% of this habitat in the North Sea and Celtic Sea was subject to fishing pressure by bottom otter, beam and mid-water trawls. Coarse sediment communities have greater resilience and faster recovery rates that those in fine sediments but 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.
Expert opinion is that there has been a substantial reduction in quality of this habitat, most likely an intermediate decline affecting more than 50% 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 Vulnerable 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 |
| Vulnerable | C/D1 |
| Europe | |
| Red List Category | Red List Criteria |
| Vulnerable | C/D1 |
Confidence in the assessment
medium
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 dredging
- Pollution
- Marine water pollution
- Toxic chemical discharge from material dumped at sea
- Synthetic compound contamination
- Natural System modifications
- Human induced changes in hydraulic conditions
- Removal of sediments (mud...)
- Extraction of sea-floor and subsoil minerals (e.g. sand, gravel, rock, oil, gas)
- Change of sea-floor substrate
- Climate change
- Changes in abiotic conditions
- Water flow changes (limnic, tidal and oceanic)
- Wave exposure changes
Habitat restoration potential
Naturally subject to disturbance therefore likely to recover character and functionality relatively quickly if the substrate and hydrographic conditions are the same.
Studies of recovery following aggregate extraction indicate that in areas of weak tidal stress physical recovery may take up to 20 years and biological recovery up to 12 years. These time scale are much reduced in areas of moderate or strong tidal stress and in the latter case may occur in less than 5 years.
Studies of recovery following aggregate extraction indicate that in areas of weak tidal stress physical recovery may take up to 20 years and biological recovery up to 12 years. These time scale are much reduced in areas of moderate or strong tidal stress and in the latter case may occur in less than 5 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 could include the regulation of fishing methods which damage or disturb seabed communities and other activities such as dredging and aggregate extraction which cause loss of the substratum and affect the hydrographic regimes. Additionally, water quality improvement programmes to reduce the risk of toxic contamination and reconnecting sediment supplies should also be considered. Any of these measures may be incorporated into management schemes for Marine Protected Areas.
List of conservation and management needs
- Measures related to wetland, freshwater and coastal habitats
- Restoring/Improving water quality
- Restoring/Improving the hydrological regime
- 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
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 | ||||
| Macaronesia | ||||
| Kattegat |
Extent of Occurrence, Area of Occupancy and habitat area
| Extent of Occurrence (EOO) (Km2) | Area of Occupancy (AOO) | Current estimated Total Area | Comment | |
|---|---|---|---|---|
| EU28 | 4,560,913 | 1,803 | >27,113 | 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. No precise figure |
| EU28+ | >1,803 | >27,113 | 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).
EOO = the area (km2) of the envelope around all occurrences of a habitat (calculated by a minimum convex polygon).
Characteristic species
Not available
Legal status
Relation to other habitat types mentioned in legal instruments
| Legal text | Annex | Name in legal text | Code in legal text |
Habitat type relationship |
More information |
|---|---|---|---|---|---|
| Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild fauna and flora - consolidated version 01/01/2007 | Annex I: natural habitat types of community interest whose conservation requires the designation of special areas of conservation | Sandbanks which are slightly covered by sea water all the time | 1110 | Overlap | http://ec.europa.eu/environm...rective/index_en.htm |
Vegetation types
Relation to vegetation types (syntaxa)
Not availableOther classifications
Not available
