Biodiversity & Conservation

Barnacles and Patella spp. on exposed or moderately exposed, or vertical sheltered, eulittoral rock



Image Jon Davies - View of vertical bedrock shore. Image width ca XX cm.
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Distribution map

LR.ELR.MB.BPat.Fvesl recorded (dark blue bullet) and expected (light blue bullet) distribution in Britain and Ireland (see below)

  • EC_Habitats

Text page icon Habitat description

Map icon Distribution of biotope in Britain and Ireland Recorded from most coasts of Britain and Ireland except the south-east coast of Britain where there is an absence of hard substrata.
National importance Widespread

Text page icon Description of biotope

For a full description of this biotope including characterizing species, distribution, survey information and references visit JNCC

Exposed or moderately exposed upper and mid eulittoral bedrock and boulders are characterized by dense barnacles Semibalanus balanoides and the limpet Patella vulgata. In the south-west Chthamalus spp. can be the dominant barnacle. Patella ulyssiponensis predominates in the south-west, but in the north is restricted to very exposed conditions. The barnacles may be covered by Porphyra on the upper shore of exposed sites. Patches of Lichina pygmaea may be prominent, especially in the south, where this may form a distinct Lichina zone (ELR.BPat.Lic). Cracks and crevices in the rock provide a refuge for small mussels Mytilus edulis, winkles Littorina saxatilis and the dog whelk Nucella lapillus. Damp crevices are also frequently occupied by red algae, particularly Osmundea pinnatifida, Mastocarpus stellatus and encrusting coralline algae. With decreasing wave exposure Fucus vesiculosus is able to survive, gradually replacing the barnacles and Patella biotope (see MLR.FvesB). On such moderately exposed shores ELR.BPat may occur on steep and vertical faces, while fucoids dominate the flatter areas. It should not be confused with more exposed shores characterized by Fucus vesiculosus f. linearis and Chthamalus spp. (ELR.BPat.Fvesl). In areas of soft rock (e.g. shales), the barnacles may be scarce or absent and the rock dominated by Patella. (Information taken from the Marine Biotope Classification for Britain and Ireland, Version 97.06: Connor et al., 1997a, b).

Additional information icon Additional information

This review can be cited as follows:

Hill, J.M. 2001. Barnacles and Patella spp. on exposed or moderately exposed, or vertical sheltered, eulittoral rock. Marine Life Information Network: Biology and Sensitivity Key Information Sub-programme [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 01/12/2015]. Available from: <>