Description of biotope or habitat type
Enteromorpha spp. on freshwater-influenced and/or unstable upper eulittoral rock
Habitat (physical) description
|Salinity||Full (30-35 ppt), Variable (18-35 ppt)|
|Wave exposure||Very exposed, Exposed, Moderately exposed, Sheltered|
|Substratum||Chalk, firm mud, bedrock, boulders|
|Zone||Eulittoral - upper, Littoral fringe - lower|
|Depth Band||Upper shore|
|Other Features||Physical disturbance|
Download comparative physical and biological data. The comparative tables enable a rapid comparison of the species composition and principal physical characteristics between a given set of biotopes.
- 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.
Upper shore hard substratum that is relatively unstable (e.g. soft rock) or subject to considerable freshwater runoff is typically very species poor and characterised by a dense mat of Enteromorpha spp., though Ulva lactuca can occur as well. It occurs in a wider zone spanning from the supralittoral down to the upper eulittoral, across a wide range of wave exposures range. This biotope is generally devoid of fauna, except for occasional limpets Patella vulgata, winkles Littorina littorea or Littorina saxatilis and barnacles Semibalanus balanoides.
This band of green seaweeds is usually found above a zone dominated by a mixture Enteromorpha spp. and Porphyra spp. (EntPor) or a Fucus spiralis or Fucus ceranoides zone (Fspi; Fcer), and may replace the Pelvetia canaliculata zone (PelB). It can be found below a zone dominated by yellow and grey lichens. In very sheltered areas the seagrass Ruppia maritima can be found above this biotope while different wracks such as Fucus spp. can dominate the zone below (Rup; Asc; Fspi).
Seasonal fluctuations in the abundance of the Enteromorpha spp. and the occurrence of the other green seaweeds species will occur.
|Taxon||Relative importance of taxon for defining this community (%)||Typical abundance - SACFOR scale||% of core records where taxon was recorded|
|Semibalanus balanoides||4||Rare||21-40 %|
|Patella vulgata||3||Occasional||21-40 %|
|Littorina saxatilis||2||Occasional||21-40 %|
|Enteromorpha intestinalis||2||21-40 %|
|Enteromorpha prolifera||2||21-40 %|
|Ulva lactuca||1||1-20 %|