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Marine Habitat Classification

Description of biotope or habitat type

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   Laminaria hyperborea and foliose red seaweeds on moderately exposed infralittoral rock

Physical habitat description

Salinity Full (30-35 ppt)
Wave exposure Moderately exposed
Tidal streams Strong (3-6 kn), Moderately strong (1-3 kn), Weak (>1 kn)
Substratum Bedrock; boulders
Zone Infralittoral
Depth Band 0-5 m, 5-10 m, 10-20 m
Other Features

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.Lhyp <I>Laminaria hyperborea</I> and foliose red seaweeds on moderately exposed infralittoral 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.


Moderately exposed infralittoral bedrock and boulders characterised by a canopy of the kelp Laminaria hyperborea beneath which is an under-storey of foliose red seaweeds and coralline crusts. Some red seaweeds can be found as epiphytes on the kelp stipes and include Delesseria sanguinea and Phycodrys rubens. Other red seaweeds present include the Plocamium cartilagineum, Metacallophyllis laciniata, Cryptopleura ramosa and the brown seaweeds Dictyota dichotoma and Cutleria multifida. The kelp fronds can be colonised by the hydroid Obelia geniculata or the bryozoans Membranipora membranacea. The echinoderm Antedon bifida, the ascidian Clavelina lepadiformis, the tube-building polychaete Spirobranchus triqueter, the anthozoans Alcyonium digitatum and Urticina felina can be found on the rock beneath the canopy. Mobile species often present include the gastropods Steromphala cineraria and Calliostoma zizyphinum and the echinoderms Echinus esculentus and Asterias rubens. Five variants has been described: Kelp forest (Lhyp.Ft), kelp park (Lhyp.Pk), grazed kelp forest (Lhyp.GzFt), grazed kelp park (Lhyp.GzPk) and kelp with Sabellaria spinulosa reefs (Lhyp.Sab). This suite of biotopes differs from the wave exposed L. hyperborea biotopes (KFaR) by having a lower diversity of cushion-forming faunal species. The foliose red seaweed component of the two suites of biotopes may also differ in composition with a tendency for Lhyp to include some more delicate filamentous species.


No situation data available.

Temporal variation

Not known

Characterising species

Taxon Relative importance of taxon for defining this community (%) Typical abundance - SACFOR scale % of core records where taxon was recorded
Laminaria hyperborea 19 Abundant 81-100%
Corallinaceae 9 Common 61-80%
Echinus esculentus 6 Frequent 61-80%
Asterias rubens 5 Occasional 61-80%
Delesseria sanguinea 4 Frequent 41-60%
Phycodrys rubens 4 Frequent 41-60%
Plocamium cartilagineum 4 Frequent 41-60%
Steromphala cineraria 3 Occasional 41-60%
Spirobranchus triqueter 3 Frequent 41-60%
Alcyonium digitatum 2 Occasional 41-60%
Metacallophyllis laciniata 2 Occasional 41-60%
Dictyota dichotoma 2 Frequent 41-60%
Membranipora membranacea 1 Frequent 21-40%
Antedon bifida 1 Frequent 21-40%
Clavelina lepadiformis 1 Occasional 21-40%
Cutleria multifida 1 Frequent 21-40%
Obelia geniculata 1 Frequent 21-40%

Similar biotopes or habitat types

L. hyperborea forest with a faunal cushion (sponges and polyclinids) and foliose red seaweeds on very exposed upper infralittoral rock. Both have dense red algae communities, but IR.MIR.KR.Lhyp lacks the dense cushion forming fauna associated with the more exposed biotopes.

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