Red List habitat classification > RL - Marine habitats > RLNEA - Atlantic > NEAA1.41 Communities of Atlantic littoral rockpools

Communities of Atlantic littoral rockpools

Quick facts

Red List habitat type code NEAA1.41
Threat status
Europe Least Concern
EU Least Concern
Relation to
Source European Red List habitat factsheet
European Red List of habitats reports
European Red List of habitats (Excel table)

Summary

Rockpools occur where the topography of the shore allows seawater to be retained within depressions in the bedrock producing pools on the retreat of the tide. As the associated communities are permanently submerged they are not directly affected by height on the shore and normal rocky shore zonation patterns do not apply. Factors such as pool depth, surface area, volume, orientation to sunlight, shading, internal topography, sediment content and type, together with wave exposure, shore height, and hence flushing rate, and the presence of absence of freshwater runoff, results in large spatial variation in community structure, even between adjacent pools at the same shore height.

Shallow rockpools in the mid to upper shore are characterised by encrusting coralline algae and Corallina officinalis. Deeper rockpools on the mid to lower shore can support fucoids and some sublittoral species such as kelp. Those rockpools influenced by the presence of sand are characterised by sand-tolerant seaweed such as Furcellaria lumbricalis and Polyides rotundus. Where more stable sand occurs in the base of the rockpool sea-grass beds can occur. Shallow rockpools on mixed cobbles, pebbles, gravel and sand may be characterised by hydroids. A very rough guideline to the terms shallow and deep rockpools: shallow rockpools do not support kelp, whereas deep rockpools do. Rockpools on the upper shore which are subject to rainwater influence and wide fluctuations in temperature are not included in this habitat type. This habitat also does not include shallow standing water on compacted sediment or mixed substrata.

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

The nature of this habitat means it can be ephemeral and subject to significant natural fluctuations as a result of patterns of erosion and deposition on the shore and climatic conditions. Survey information confirms that this habitat has a widespread distribution in the North East Atlantic. Examples have been studied in detail in some localities and although there have been some changes, overall it is considered to have been stable in extent. It does not have a narrow geographical range and the distribution of the habitat is such that the identified threats are unlikely to affect all localities at once. This habitat has therefore been assessed as Least Concern for both the EU 28 and EU 28+.
EU
Red List Category Red List Criteria
Least Concern
Europe
Red List Category Red List Criteria
Least Concern

Confidence in the assessment

low
Red List of habitat categories and criteria descriptions

Pressures and threats

  • Pollution
    • Pollution to surface waters (limnic, terrestrial, marine & brackish)
    • Nutrient enrichment (N, P, organic matter)
    • Input of contaminants (synthetic substances, non-synthetic substances, radionuclides) - diffuse sources, point sources, acute events
    • Marine water pollution
    • Oil spills in the sea
  • Invasive, other problematic species and genes
    • Invasive non-native species

Habitat restoration potential

Generally, the effects of chronic impacts on this habitat are reversible provided the disturbance is stopped. Recovery from acute impacts is also possible but may take much longer depending on the type and scale of the impact as well as physical factors such as position on the shore, size and depth of the rock pool habitat.

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

Conservation and management measures which would benefit this habitat are mostly general rather than specific measures. They include pollution control and regulation, development control and contingency plans to be followed in the event of a major pollution incident and measures to reduce global warming and sea level rise.

List of conservation and management needs

  • Measures related to wetland, freshwater and coastal habitats
    • Restoring/Improving water quality
  • Measures related to marine habitats
    • Other marine-related measures
  • Measures related to spatial planning
    • Other marine-related measures

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
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 316,131 231 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+ 231 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.
Algae Chondrus crispus
Algae Cladophora rupestris
Algae Corallina officinalis
Algae Dumontia contorta
Algae Fucus serratus
Algae Furcellaria lumbricalis
Algae Gastroclonium ovatum
Algae Halidrys siliquosa
Algae Himanthalia elongata
Algae Laminaria digitata
Algae Laminaria saccharina
Algae Mastocarpus stellatus
Algae Membranoptera alata
Algae Palmaria palmata
Algae Polyides rotundus
Algae Saccorhiza polyschides
Invertebrates Actinia equina
Invertebrates Amphipholis squamata
Invertebrates Carcinus maenas
Invertebrates Elminius modestus
Invertebrates Gibbula cineraria
Invertebrates Halichondria panicea
Invertebrates Kirchenpaueria pinnata
Invertebrates Littorina littorea
Invertebrates Mytilus edulis
Invertebrates Obelia longissima
Invertebrates Ophiothrix fragilis
Invertebrates Pagurus bernhardus
Invertebrates Patella vulgata
Invertebrates Pomatoceros triqueter
Invertebrates Semibalanus balanoides
Species scientific name English common name Species group
Chondrus crispus Algae
Cladophora rupestris Algae
Corallina officinalis Algae
Dumontia contorta Algae
Fucus serratus Algae
Furcellaria lumbricalis Algae
Gastroclonium ovatum Algae
Halidrys siliquosa Algae
Himanthalia elongata Algae
Laminaria digitata Algae
Laminaria saccharina Algae
Mastocarpus stellatus Algae
Membranoptera alata Algae
Palmaria palmata Algae
Polyides rotundus Algae
Saccorhiza polyschides Algae
Actinia equina Invertebrates
Amphipholis squamata Invertebrates
Carcinus maenas Invertebrates
Elminius modestus Invertebrates
Gibbula cineraria Invertebrates
Halichondria panicea Invertebrates
Kirchenpaueria pinnata Invertebrates
Littorina littorea Invertebrates
Mytilus edulis Invertebrates
Obelia longissima Invertebrates
Ophiothrix fragilis Invertebrates
Pagurus bernhardus Invertebrates
Patella vulgata Invertebrates
Pomatoceros triqueter Invertebrates
Semibalanus balanoides Invertebrates

Vegetation types

Relation to vegetation types (syntaxa)

Not available

Other classifications

Not available
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