Red List habitat classification > RL - Marine habitats > RLNEA - Atlantic > NEAA4.11 Faunal communities on very tide-swept Atlantic upper circalittoral rock

Faunal communities on very tide-swept Atlantic upper circalittoral rock

Quick facts

Red List habitat type code NEAA4.11
Threat status
Europe Data Deficient
EU Data Deficient
Relation to
Source European Red List habitat factsheet
European Red List of habitats reports
European Red List of habitats (Excel table)

Summary

This habitat develops in extremely wave-exposed to exposed conditions where circalittoral bedrock and boulders are subject to strong or very strong tidal streams. It is typically found in tidal straits and narrows and is characterised by species that are capable of maintaining a foothold under these conditions. They either form a flat, adherent crust, as in the case of the barnacle Balanus crenatus, or have strong attachment points and are flexible, bending with the tide, such as the turf of the hydroid Tubularia indivisa.

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

There is a lack of comprehensive information on the distribution and abundance of this habitat in the North East Atlantic however as it is known to occur in locations as widely separated as the Azores, the west coast of Ireland, St.Kilda to the west of the Outer Hebrides, and the east coast of Shetland it is not considered to have a small natural range or occur in just a few locations.There is insufficient information to provide an overall estimate of historical, recent and possible future trends in quantity and quality.
This habitat has large EOO and therefore qualifies as Least Concern under criterion B1. The AOO figure is known to be an underestimate. Given the lack of information on trends in quantity and quality, and the fact that the overall distribution is unknown, expert opinion is this habitat should be considered Data Deficient for both the EU 28 and EU 28+.
EU
Red List Category Red List Criteria
Data Deficient
Europe
Red List Category Red List Criteria
Data Deficient

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
  • Pollution
    • Pollution to surface waters (limnic, terrestrial, marine & brackish)
    • Nutrient enrichment (N, P, organic matter)
  • Natural System modifications
    • Human induced changes in hydraulic conditions

Habitat restoration potential

Information is limited, but it is clear that a number of the more prominent members of this habitat are relatively long lived, and fairly slow growing such as sea fans and cup corals. It may be concluded that because of this communities which they dominate will be relatively stable with time, but that when they are damaged recovery to their original complexity may be slow. This recovery will be hindered by the fact that for a number of species recruitment can be very spasmodic, particularly for species near the limits of their geographical range.

Trends in extent

Average current trend in quantity

Unknown Unknown
EU28 EU28+

Trends in quality

Average current trend in quality

Unknown Unknown
EU28 EU28+

Conservation and management needs

There are few conservation and management measures specifically directed at this habitat. Some are within designated protected areas and can therefore benefit from general measures which regulate activities in such areas and aim to prevent deterioration in water quality.

List of conservation and management needs

  • Measures related to marine habitats
    • Other marine-related measures
  • Measures related to spatial planning
    • Establish protected areas/sites

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 Unknown Unknown
Celtic Seas
Kattegat
Greater North Sea
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 >137,964 >39 Unknown 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.
EU28+ >39 Unknown 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 Actinothoe sphyrodeta
Invertebrates Alcyonidium diaphanum
Invertebrates Alcyonium digitatum
Invertebrates Asterias rubens
Invertebrates Balanus crenatus
Invertebrates Cancer pagurus
Invertebrates Clathrina coriacea
Invertebrates Corynactis viridis
Invertebrates Dysidea fragilis
Invertebrates Esperiopsis fucorum
Invertebrates Flustra foliacea
Invertebrates Halichondria panicea
Invertebrates Hemimycale columella
Invertebrates Henricia oculata
Invertebrates Metridium senile
Invertebrates Myxilla incrustans
Invertebrates Nucella lapillus
Invertebrates Pachymatisma johnstonia
Invertebrates Sagartia elegans
Invertebrates Sertularia argentea
Invertebrates Tubularia indivisa
Invertebrates Urticina felina
Species scientific name English common name Species group
Actinothoe sphyrodeta Invertebrates
Alcyonidium diaphanum Invertebrates
Alcyonium digitatum Invertebrates
Asterias rubens Invertebrates
Balanus crenatus Invertebrates
Cancer pagurus Invertebrates
Clathrina coriacea Invertebrates
Corynactis viridis Invertebrates
Dysidea fragilis Invertebrates
Esperiopsis fucorum Invertebrates
Flustra foliacea Invertebrates
Halichondria panicea Invertebrates
Hemimycale columella Invertebrates
Henricia oculata Invertebrates
Metridium senile Invertebrates
Myxilla incrustans Invertebrates
Nucella lapillus Dog whelk Invertebrates
Pachymatisma johnstonia Invertebrates
Sagartia elegans Invertebrates
Sertularia argentea Invertebrates
Tubularia indivisa Invertebrates
Urticina felina Invertebrates

Vegetation types

Relation to vegetation types (syntaxa)

Not available

Other classifications

Not available
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