Description of biotope or habitat type
Fucus spiralis on full salinity upper eulittoral mixed substrata
Physical habitat description
|Full (30-35 ppt)
|Exposed, Moderately exposed, Sheltered
|Eulittoral - upper
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- Records used to define the biotope (core records)
- Other records assigned to this biotope, marked as 'certain'
- Other records assigned to this biotope, marked as 'uncertain'
Point data based on records in the UK Marine Recorder Snapshot.
Moderately exposed to sheltered full salinity upper eulittoral mixed substrata characterised by a band of the wrack Fucus spiralis. Occasional clumps of the wrack Pelvetia canaliculata can be overgrowing the black lichen Verrucaria maura and the olive green lichen Verrucaria mucosa. On the more stable boulders underneath the fronds the red crust Hildenbrandia rubra can be found along with the barnacle Semibalanus balanoides and the limpet Patella vulgata. The winkles Littorina littorea and Littorina saxatilis can be found on and among the boulders and cobbles, while amphipods and the crab Carcinus maenas can be present either underneath the boulders or among the brown seaweeds. The green seaweed Ulva intestinalis can occur in some abundance especially during the summer.
This zone usually lies below a zone dominated by the wrack P. canaliculata (PelB; Pel). Vertical surfaces in this zone, especially on moderately exposed shores, often lack the fucoids and are characterised by a barnacle-limpet dominated community (Sem).In areas of extreme shelter, such as in Scottish sea lochs, the P. canaliculata and F. spiralis zones often merge together forming a very narrow band. Fspi.X occur above the wracks Ascophyllum nodosum (Asc.X) and/or Fucus vesiculosus (Fves.X) zones. These two fucoids may also occur among the F. spiralis, although F. spiralis always dominates. Fspi.X can also be found above a barnacle S. balanoides and winkle L. littorea dominated biotope (BLitX).
Ephemeral green seaweeds such as E. intestinalis can occur in some abundance during the summer when the growth conditions are optimal.
|Relative importance of taxon for defining this community (%)
|Typical abundance - SACFOR scale
|% of core records where taxon was recorded
Similar biotopes or habitat types
Classification history of this biotope or habitat type