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Exposed to moderately exposed mid eulittoral bedrock and boulders are frequently characterised by a mosaic of the barnacle Semibalanus balanoides and the wrack Fucus vesiculosus. The limpet Patella vulgata and the whelk Nucella lapillus are typically present, whilst the anemone Actinia equina and small individuals of the mussel Mytilus edulis are confined to crevices. Underneath the F. vesiculosus is a community of red seaweeds, including Corallina officinalis, Mastocarpus stellatus and Osmundea pinnatifida, usually with the winkles Littorina littorea and Littorina spp. present. Opportunistic seaweeds such as Ulva intestinalis may occur in patches recently cleared on the rock or growing on the M. edulis.

Lower eulittoral and sublittoral fringe bedrock and boulders subject to mild sand-scouring characterised by a canopy of the wracks Fucus serratus or Fucus vesiculosus, beneath which a mat of the sand-binding red seaweed Rhodothamniella floridula occurs. These mats can form distinct areas without F. serratus. The small hummocks of R. floridula also contain a diversity of other red seaweeds tolerant of sand scour, e.g. Palmaria palmata, Chondrus crispus, coralline crusts and Mastocarpus stellatus. The brown seaweed Cladostephus spongiosus or the ephemeral green seaweed Ulva intestinalis, Ulva lactuca or Cladophora rupestris may occur. The hydroid Dynamena pumila can form colonies on the F. serratus fronds. The barnacle Semibalanus balanoides, the limpet Patella vulgata, the anemone Actinia equina and the polychaete Spirobranchus triqueter may be present where bedrock are available along with a few winkles such as Littorina littorea. In addition, polychaetes and amphipods may burrow into the R. floridula mat, while the mussel Mytilus edulis is restricted to small crevices in the bedrock. The species diversity of this biotope is normally low and there can be much variation in the species composition from site to site.

Exposed to moderately exposed steep, lower littoral fringe rock and mixed substrata characterised by the wrack Pelvetia canaliculata and sparse barnacles Chthamalus montagui and Semibalanus balanoides. On sheltered shores the biotope is restricted to vertical faces. The limpet Patella vulgata and the wrack Fucus spiralis are usually present as well. P. canaliculata typically overgrows a crust of the black lichen Verrucaria maura or on occasion Verrucaria mucosa, in contrast to the red crust Hildenbrandia rubra on very sheltered shores. The winkle Littorina saxatilis is frequently present underneath the fronds of P. canaliculata. Some geographical variation are present and southern and western shores are typically characterised by the barnacle C. montagui or Chthamalus stellatus while S. balanoides dominates on northern and eastern shores. On mixed substrata the barnacle Austrominius modestus may be present.

Lower eulittoral bedrock and stable boulders on moderately exposed to sheltered shores with a canopy of the wrack Fucus serratus and an associated fauna consisting of the limpet Patella vulgata, the barnacle Semibalanus balanoides, the whelk Nucella lapillus, the anemone Actinia equina and the sponge Halichondria panicea. Green seaweeds such as Ulva intestinalis and Ulva lactuca are usually present among/beneath the F. serratus canopy. Three variants of this biotope are described. These are: F. serratus with red seaweeds (Fser.R) and F. serratus with under-boulder communities (Fser.Bo) with sponges. Lastly, a F. serratus and piddocks community on soft rock has been identified (Fser.Pid). Dense F. serratus with fewer red seaweeds occurs on more sheltered shores (Fserr).

Moderately exposed rocky shores characterised by a mosaic of fucoids and barnacles on bedrock and boulders, where the extent of the fucoid cover is typically less than the blanket cover associated with sheltered shores. Other species are normally present as well in this habtat including the winkle Littorina littorea, the whelk Nucella lapillus and the red seaweed Mastocarpus stellatus. Beneath the band of yellow and grey lichens at the top of the shore is a zone dominated by the wrack Pelvetia canaliculata, scattered barnacles, while the black lichen Verrucaria maura covers the rock surface (PelB). Below, on the mid shore the wrack Fucus vesiculosus generally forms a mosaic with the barnacle Semibalanus balanoides and the limpet Patella vulgata (FvesB). Finally, the wrack Fucus serratus, dominates the lower shore, while a variety of red seaweeds can be found underneath the F. serratus canopy (Fser). A number of variants have been described: lower shore bedrock and boulders characterised by mosaics of F. serratus and turf-forming red seaweeds (Fser.R); where the density of F. serratus is greater (typically Common - Superabundant) and the abundance of red seaweeds less Fserr.FS should be recorded. The presence of boulders and cobbles on the shore can increase the micro-habitat diversity, which often results in a greater species richness. Although the upper surface of the boulders may bear very similar communities to Fserr.FS there is often an increase in fauna (crabs, tube-forming polychaetes, sponges and bryozoans) and Fser.Bo should be recorded. Sand-influenced exposed to moderately exposed lower shore rock can be characterised by dense mats of Rhodothamniella floridula (Rho).

Exposed to moderately exposed upper eulittoral bedrock characterised by a band of the spiral wrack Fucus spiralis overlying the black lichen Verrucaria maura and the olive green lichen Verrucaria mucosa. Underneath the fronds of F. spiralis is a community consisting of the limpet Patella vulgata, the winkles Littorina saxatilis and Littorina littorea, the mussel Mytilus edulis and the barnacle Semibalanus balanoides. The whelk Nucella lapillus can be found in cracks and crevices preying on the mussels and barnacles. During the summer months ephemeral green seaweeds such as Ulva intestinalis can be common. The insect Anurida maritima can be present in this zone taking shelter in cracks and crevices when the tide comes in.

Moderately exposed lower eulittoral bedrock characterised by mosaics of the wrack Fucus serratus and turf-forming red seaweeds including Osmundea pinnatifida, Mastocarpus stellatus or Corallina officinalis. The hydroid Dynamena pumila can occur in dense populations on the F. serratus fronds whilst the sponge Halichondria panicea can cover the bedrock beneath. Underneath the canopy a number of other red seaweeds may be present including Palmaria palmata, Lomentaria articulata,Membranoptera alata and Chondrus crispus. Green seaweeds such as Cladophora rupestris, Ulva intestinalis and Ulva lactuca are present though usually in small numbers. In addition, such shores provide a greater number of permanently damp refuges between the stones and underneath the seaweed canopy. Within these micro-habitats species such as the limpet Patella vulgata, the barnacle Semibalanus balanoides or the whelk Nucella lapillus can be found in lower abundance than higher up the shore. If a few boulders are present then the winkle Littorina littorea and the crab Carcinus maenas can be found on or underneath the boulders.

The lower eulittoral zone on soft rock shores (e.g. chalk) characterised by the wrack Fucus serratus. Much of the community associated with this biotope is the same as the biotope Fserr.FS, but certain taxa are specific to the soft underlying substrata. Rock-boring fauna including the piddocks Barnea spp., Pholas dactylus and Hiatella arctica can occur in dense aggregations. Burrowing polychaetes such as Polydora spp. can also occur in high numbers only visible due to their long, slender palps waving in the water as they occupy holes in the top few centimetres of the rock. A dense red algal turf occurs beneath the F. serratus and includes Gelidium pusillum, Osmundea pinnatifida, Palmaria palmata, Lomentaria articulata and Rhodothamniella floridula, but also calcareous algae such as Corallina officinalis and coralline crusts including the red-violet encrusting algae Phymatolithon lenormandii are present. Infaunal taxa such as various amphipods may be common amongst the seaweeds. The empty piddock holes may provide a refuge for species such as the anemone Actinia equina and the mussel Mytilus edulis while the barnacle Semibalanus balanoides, the limpet Patella vulgata can be present on the surface of the soft rock. The whelk Nucella lapillus, the winkles Littorina littorea and Littorina fabalis and the top shell Steromphala cineraria are all present on the soft rock among the seaweeds. The high number of characterising species is partly caused by the low number of records used to define this biotope. The high % frequency of occurrence is partly a result of the low number of records. More data is needed to validate this biotope description.

Exposed to moderalety exposed lower eulittoral boulders with the wrack Fucus serratus community of a high species richness as the presence of the boulders increases the micro-habitat diversity. The upper surfaces of the boulders are colonised by a very similar fauna to the other F. serratus biotopes, including species such as the limpet Patella vulgata, the whelk Nucella lapillus, the anemone Actinia equina and the barnacle Semibalanus balanoides. The shaded sides of the boulders are, depending on environmental conditions, often colonised by a variety of foliose red seaweeds, including Mastocarpus stellatus, Lomentaria articulata, Osmundea pinnatifida, Palmaria palmata and Chondrus crispus. Coralline algae such as Corallina officinalis and coraline crusts, as well as the green seaweeds Ulva intestinalis and Ulva lactuca, can be found underneath the F. serratus canopy or in patches on the boulders. The species composition underneath the boulders varies considerably depending on the underlying substratum. On muddy shores the fauna living under the boulders may be limited to a few infaunal species, such as the polychaete Cirratulus cirratus. Where more space is available beneath the boulders there may be a rich assemblage of animals. Characteristic mobile species include the crabs Porcellana platycheles and Carcinus maenas. Also present on and beneath the boulders are the tube-forming polychaete Spirobranchus triqueter, spirorbid polychaetes and a few winkles such as Littorina and Littorina littorea or even the top shell Steromphala cineraria. Encrusting colonies of the sponge Halichondria panicea are also typical of the undersides of boulders, while the hydroid Dynamena pumila colonies can be found on the F. serratus fronds. The richest examples of this biotope also contain a variety of brittlestars, ascidians and small hydroids.