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Marine Habitat Classification

Description of biotope or habitat type

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   Laminaria hyperborea on moderately exposed vertical rock.

Physical habitat description

Salinity Full (30-35 ppt)
Wave exposure Extremely exposed, Very exposed, Exposed, Moderately exposed, Sheltered
Tidal streams Moderately strong (1-3 kn), Weak (>1 kn), Very weak (negligible)
Substratum Bedrock
Zone Infralittoral
Depth Band 0-5 m, 5-10 m, 10-20 m
Other Features Vertical rock.

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 IR.MIR.KR.LhypVt <I>Laminaria hyperborea</I> on moderately exposed vertical 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'
  • Predicted extent of the level 3 (for sublittoral rock & deep sea) or 4 (for sublittoral sediment) habitat

Point data based on records in the UK Marine Recorder Snapshot. Predicted habitat extent is from UKSeaMap.


LhypVt is found on moderately exposed coasts in moderately strong to weak tidal streams generally in 0-20m water depth. It is characterised by the kelp Laminaria hyperborea, the soft coral Alcyonium digitatum and crinoid Antedon bifida. This biotope is relatively species poor when compared to similar biotopes in more exposed environments e.g. LhypRVt. The urchin Echinus esculentus may be frequently observed grazing the vertical rock face. This biotope may have 2 sub-biotopes. One is characterised by the frequent occurrence of the sea squirt Clavelina lepadiformis and the red seaweeds Phycodrys rubens and Cryptopleura ramosa. The brown seaweed Dictyota dichotoma may also be frequent in this sub-biotope. The second sub-biotope is more species poor than the previous one and is characterised by the common occurrence of Alcyonium digitatum, which is only occasional in the other variant.


Open rocky coasts in northern Britain, particularly North Sea coasts.

Temporal variation

No temporal data avialable

Characterising species

Taxon Relative importance of taxon for defining this community (%) Typical abundance - SACFOR scale % of core records where taxon was recorded
Echinus esculentus 10 Frequent 81-100%
Laminaria hyperborea 9 Frequent 61-80%
Alcyonium digitatum 8 Frequent 61-80%
Asterias rubens 8 Occasional 61-80%
Corallinaceae 5 Common 41-60%
Clavelina lepadiformis 4 Occasional 61-80%
Spirobranchus triqueter 4 Frequent 41-60%
Antedon bifida 3 Frequent 41-60%
Urticina felina 3 Occasional 41-60%
Calliostoma zizyphinum 2 Occasional 41-60%
Caryophyllia smithii 2 Occasional 41-60%
Cryptopleura ramosa 2 Frequent 41-60%
Delesseria sanguinea 2 Occasional 21-40%
Dictyota dichotoma 2 Frequent 21-40%
Steromphala cineraria 2 Occasional 41-60%
Phycodrys rubens 2 Frequent 41-60%
Plocamium cartilagineum 2 Occasional 21-40%
Botryllus schlosseri 1 Occasional 21-40%
Cancer pagurus 1 Rare 21-40%
Henricia 1 Occasional 41-60%
Necora puber 1 Occasional 21-40%
Cylista elegans 1 Occasional 21-40%

Similar biotopes or habitat types

Much richer; red seaweeds component usually denser.

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