Biodiversity & Conservation

Sabellaria alveolata reefs on sand-abraded eulittoral rock



Image Rohan Holt - Sabellaria alveolata reefs on sand abraded eulittoral rocks. Image width ca 150 cm.
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Distribution map

LR.MLR.Sab.Salv recorded (dark blue bullet) and expected (light blue bullet) distribution in Britain and Ireland (see below)

  • EC_Habitats
  • UK_BAP

Text page icon Habitat description

Map icon Distribution of biotope in Britain and Ireland In Britain, Sabellaria alveolata distribution is restricted to south and west coasts with the eastern limit in Lyme Bay. The northern limit is the outer Solway Firth. It is also found on south, west and north coasts of Ireland. To date, MLR.Salv has only been recorded in the Solway Firth and along the Cumbrian coast, western Wales, and the Severn Estuary. In Northern Ireland reefs have been recorded from the Down coast (Rossglass and Glassdrummand) although surveys are incomplete. It has also been recorded at two sites in Ireland, Ballycotton Bay (south) and Killala Bay, (north-west).
National importance Scarce

Text page icon Description of biotope

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

Many wave-exposed boulder scar grounds in the eastern basin of the Irish Sea (and as far south as Cornwall), are characterized by reefs of Sabellaria alveolata which build tubes from the mobile sand surrounding the boulders and cobbles. The tubes formed by Sabellaria alveolata form large reef-like hummocks, which serve to further stabilize the boulders. Other species in this biotope include the barnacles Semibalanus balanoides, Balanus crenatus and Elminius modestus and the molluscs Patella vulgata, Littorina littorea, Nucella lapillus and Mytilus edulis. Low abundances of algae tend to occur in areas of eroded reef. The main algal species include Porphyra spp., Mastocarpus stellatus, Ceramium spp., Fucus vesiculosus, Fucus serratus, Ulva spp. and Ulva spp. On exposed surf beaches in the south-west Sabellaria forms a crust on the rocks, rather than the classic honeycomb reef, and may be accompanied by the barnacle Balanus perforatus (typically common to abundant). On wave-exposed shores in Ireland, the brown alga Himanthalia elongata can also occur. (Information taken from the Marine Biotope Classification for Britain and Ireland, Version 97.06: Connor et al., 1997a, b).

Additional information icon Additional information

Sabellaria alveolata can perform important stabilization of habitat, particularly when forming raised structures and reefs (see Ecology).

This review can be cited as follows:

Jackson, A. 2005. Sabellaria alveolata reefs on sand-abraded eulittoral rock. Marine Life Information Network: Biology and Sensitivity Key Information Sub-programme [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 30/11/2015]. Available from: <>