1 result for 'LR.HLR.FT.FserT'
LR.HLR.FT.FserT Fucus serratus, sponges and ascidians on tide-swept lower eulittoral rock
Sheltered to extremely sheltered lower eulittoral bedrock, boulders and cobbles that are subject to increased tidal water movement and characterised by the wrack Fucus serratus and a rich assemblage of filter-feeding fauna. This community is encouraged by the increased water movement. It includes species such as the sponges Halichondria panicea and Hymeniacidon perlevis, which occur frequently on steep and overhanging faces. Underneath the F. serratus canopy is a diverse flora of foliose red seaweeds including Mastocarpus stellatus, Lomentaria articulata, Membranoptera alata and Chondrus crispus. The green seaweeds Cladophora spp., Ulva intestinalis and Ulva lactuca and the wrack Ascophyllum nodosum are present though usually in small numbers. On the rock underneath the seaweed canopy, species such as the limpet Patella vulgata, the barnacles Semibalanus balanoides and Balanus crenatus and the whelk Nucella lapillus can be found though in lower abundance than higher up the shore. Also present on the rock are the tube-forming polychaetes Spirobranchus triqueter and spirorbids and more mobile species such as the winkles Littorina fabalis and Littorina littorea, the top shell Steromphala cineraria and the crab Carcinus maenas. Lastly, several species of bryozoans are usually present including Electra pilosa and Alcyonidium gelatinosum, all competing for space with the hydroid Dynamena pumila, which can form dense populations on the F. serratus fronds.