Fucoids on variable salinity Atlantic littoral rock

Description (English)

Blankets of fucoid seaweeds dominating sheltered to extremely sheltered rocky shores with variable salinity. The wrack Pelvetia canaliculata (MA1-251) occurs on the upper shore, with the wrack Fucus spiralis (MA1-252) below. The middle shore is dominated by vast areas of the wrack Ascophyllum nodosum or the wrack Fucus vesiculosus (MA1-253, MA1-254) or a mixture of both. The wrack Fucus serratus covers lower shore bedrock and boulders (MA1-256). Fucus ceranoides can be found on extremly sheltered shores with variable or low salinity (MA1-257). The variable salinity communities are species impoverished compared to fucoids in full salinity or in tide-swept conditions as red seaweeds and sponges are usually absent. Underneath the canopy are a few green seaweeds including Enteromorpha intestinalis and Cladophora spp., while the red seaweed Polysiphonia lanosa can be found as an epiphyte on A. nodosum . On the rock and among the boulders are the winkles Littorina littorea and Littorina saxatilis , the crab Carcinus maenas , the barnacles Semibalanus balanoides and Elminius modestus and even the occasional mussel Mytilus edulis.
Situation: On sheltered eulittoral rocky shores with variable salinity conditions, such as sea loch or estuaries.

Source: EUNIS habitat classification