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Marine Habitat Classification


Description of biotope or habitat type

To understand more about what this page is describing, see How to use the classification. See also How to cite.

   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
Tidal streams
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.

Distribution of habitat LR.FLR.Eph.Ent <I>Enteromorpha</I> spp. on freshwater-influenced and/or unstable upper eulittoral rock

  • 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.

Description

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.

Situation

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).

Temporal variation

Seasonal fluctuations in the abundance of the Enteromorpha spp. and the occurrence of the other green seaweeds species will occur.

Characterising Species

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 74 Common 61-80 %
Enteromorpha intestinalis 2 21-40 %
Enteromorpha prolifera 2 21-40 %
Ulva lactuca 1 1-20 %

Similar biotopes

LR.FLR.Eph.EntPor
Occurs in the lower to mid-eulitttoral zone in sand influenced habitats. It has a higher species richness, which include the red seaweed Porphyra purpurea and the occasional wracks such as F. spiralis or Fucus vesiculosus. The winkle L. littorea is usually present.

LR.FLR.Eph.EphX
Occurs in more estuarine conditions and on mixed substrata. The green seaweed Ulva lactuca may be present. A very similar biotope.

Biotope history

Classification Habitat code
6.95 LRK.ENT
96.7 MLR.Eph.Ent

Photos

LR.FLR.EPH.Ent Enteromorpha spp. on freshwater-influenced and/or unstable upper eulittoral rock, Unspecified location. ANON © JNCC
LR.FLR.EPH.Ent Enteromorpha spp. on freshwater-influenced and/or unstable upper eulittoral rock, Unspecified location. ANON © JNCC
LR.FLR.EPH.Ent Enteromorpha spp. on freshwater-influenced and/or unstable upper eulittoral rock, Sussex. Kate Northen © JNCC
LR.FLR.EPH.Ent Enteromorpha spp. on freshwater-influenced and/or unstable upper eulittoral rock, Sussex. Kate Northen © JNCC

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