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Marine Habitat Classification

Description of biotope or habitat type

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   Sabellaria spinulosa with kelp and red seaweeds on sand-influenced infralittoral rock

Physical habitat description

Salinity Full (30-35 ppt)
Wave exposure Moderately exposed
Tidal streams Weak (>1 kn), Very weak (negligible)
Substratum Bedrock; boulders
Zone Infralittoral
Depth Band 0-5 m, 5-10 m
Other Features Sand-scoured

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.Sab <I>Sabellaria spinulosa</I> with kelp and red seaweeds on sand-influenced 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.


Laminaria hyperborea kelp forest on shallow infralittoral bedrock and boulders characterised by encrustations of Sabellaria spinulosa tubes which cover much of the rock, together with sand-tolerant red seaweeds such as Phyllophora pseudoceranoïdes, Dilsea carnosa and Carradoriella elongata and Vertebrata fucoides. Red seaweeds such as Plocamium cartilagineum and Delesseria sanguinea may also be found beneath the kelp canopy, although typically low in abundance. They can be colonised by the ascidian Botryllus schlosseri. The cowrie Trivia arctica can also be found here. Much of the available rock is covered with encrusting coralline algae together with patches of the encrusting sponge Halichondria panicea and the anthozoan Urticina felina. More mobile fauna include the echinoderms Asterias rubens, Henricia sanguinolenta, Echinus esculentus, and Ophiothrix fragilis, the gastropod Steromphala cineraria and the hermit crab Pagurus bernhardus. The scouring effect of mobile sand adjacent to the rock maintains a reduced underflora and fauna compared to the association of species found in non-scoured kelp forests (Lhyp.Ft). Scour-resistant fauna such as the barnacle Balanus crenatus can be locally abundant on the rock, while the bivalve Pododesmus patelliformis can be found seeking shelter underneath the cobbles. Above the effect of scour, kelp stipes may be densely colonised by red seaweeds such as Phycodrys rubens, Palmaria palmata and Membranoptera alata, together with some sponges and ascidians.


This biotope is found in the sand-laden waters of north-east England in conditions in which S. spinulosa is able to thrive. Nearby circalittoral rock is often also dominated by S. spinulosa (Sspi) but lacks the kelp and red seaweeds. As this biotope is not commonly recorded in the UK there is a scarcity of information relating to the surrounding biotopes.

Temporal variation


Characterising species

Taxon Relative importance of taxon for defining this community (%) Typical abundance - SACFOR scale % of core records where taxon was recorded
Sabellaria spinulosa 20 Abundant 81-100%
Laminaria hyperborea 15 Abundant 81-100%
Asterias rubens 6 Frequent 81-100%
Plocamium cartilagineum 6 Frequent 81-100%
Steromphala cineraria 4 Frequent 61-80%
Urticina felina 4 Frequent 61-80%
Corallinaceae 3 Frequent 61-80%
Delesseria sanguinea 3 Frequent 41-60%
Pagurus bernhardus 3 Occasional 61-80%
Carradoriella elongata 3 Common 41-60%
Echinus esculentus 3 Occasional 61-80%
Halichondria panicea 2 Common 41-60%
Henricia sanguinolenta 2 Occasional 41-60%
Ophiothrix fragilis 2 Occasional 41-60%
Trivia arctica 2 Occasional 41-60%
Electra pilosa 1 Frequent 41-60%
Balanus crenatus 1 Occasional 21-40%
Botryllus schlosseri 1 Frequent 41-60%
Dilsea carnosa 1 Occasional 41-60%
Phyllophora pseudoceranoides 1 Frequent 21-40%
Pododesmus patelliformis 1 Frequent 21-40%
Vertebrata fucoides 1 Occasional 21-40%

Similar biotopes or habitat types

A similar biotope is found in the circalittoral zone, where it lacks the algal component.

Classification history of this biotope or habitat type

Classification version Code
1997 (97.06) MIR.SabKR
1996 (6.95) MIR.SabR

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