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Concept: [Ascophyllum nodosum], sponges and ascidians on tide-swept mid eulittoral rock in the eunishabitats vocabulary

Concept URI http://eunis.eea.europa.eu/eunishabitats/A1.151
Preferred label [Ascophyllum nodosum], sponges and ascidians on tide-swept mid eulittoral rock
Definition Very sheltered to extremely sheltered areas of mid eulittoral rock that are subject to strong to moderate tidal streams, such as the narrows in sea lochs, and characterised by the wrack [Ascophyllum nodosum]. The wracks [Fucus vesiculosus] and [Fucus serratus] are occasionally present. The increased water movement encourages a rich associated fauna including several filter-feeding groups. These include the sponges [Leucosolenia] spp., [Grantia compressa, Halichondria panicea] and [Hymeniacidon perleve] which frequently occur on steep and overhanging faces of boulders and bedrock. It also includes the sea squirts [Dendrodoa grossularia] and [Ascidiella scabra], which occur on steep surfaces and beneath boulders. Hydroids such as the pink [Clava multicornis] can form colonies on [A. nodosum] while [Dynamena pumila] is more often found on [F. vesiculosus] or [F. serratus]. Underneath the canopy formed by the brown seaweeds is a diverse community of the red seaweeds [Gelidium pusillum], [Chondrus crispus], [Lomentaria articulata], [Membranoptera alata] and coralline crusts, but the green seaweeds [Enteromorpha intestinalis], [Ulva lactuca] and [Cladophora rupestris] can be present. The filamentous red seaweed [Polysiphonia lanosa] can usually be found growing on [A. nodosum]. On the rock beneath are the limpet [Patella vulgata] and the barnacle [Semibalanus balanoides], while the crab [Carcinus maenas] and a variety of winkles including [Littorina littorea], [Littorina mariae] and [Littorina obtusata] can be found on or among the boulders. The whelk [Nucella lapillus] can either be found in cracks and crevices or preying on the barnacles. Situation: This biotope occurs lower on the shore than the [Fucus spiralis] biotope (Fspi) although on some shores a narrow zone of [F. vesiculosus] (Fves) may occur immediately above the [A. nodosum]. Asc.T is found above the tide-swept [F. serratus] dominated biotope (Fserr.T). Temporal variation: [A. nodosum] can reach an age of 25 years and the communities are usually very stable. [F. vesiculosus] or [F. serratus] can occur in patches where the [A. nodosum] has been removed.
Notation A1.151
Status Valid
Status Modified 2014-01-31
Accepted Date 2014-01-31
Not Accepted Date
Has broader
Has exact match