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Marine Habitat Classification

Description of biotope or habitat type

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   Sabellaria spinulosa with a bryozoan turf and barnacles on silty turbid circalittoral rock

Physical habitat description

Salinity Full (30-35 ppt)
Wave exposure Exposed, Moderately exposed
Tidal streams Strong (3-6 kn), Moderately strong (1-3 kn)
Substratum Bedrock, boulders, cobbles, pebbles, gravel, sand
Zone Circalittoral
Depth Band 0-5 m, 5-10 m, 10-20 m, 30-50 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 CR.MCR.CSab.Sspi.ByB <I>Sabellaria spinulosa</I> with a bryozoan turf and barnacles on silty turbid circalittoral 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.


This variant is typically found encrusting the upper faces of exposed and moderately exposed circalittoral rock and mixed substrata, subject to strong and moderately strong currents and high turbidity levels. The crusts formed by the sandy tubes of the polychaete worm Sabellaria spinulosa may completely cover the rock, binding gravel and pebbles together. A diverse fauna may be found attached to this crust, and in many cases reflects the character of nearby biotopes. There is normally considerable variation in the associated fauna encountered. There may be a sparse bryozoan turf (Flustra foliacea, Alcyonidium diaphanum, Bicellariella ciliata, Crisularia plumosa and Vesicularia spinosa) attached to the Sabellaria crust and available rocky substrata. Other scour-tolerant species such as Urticina felina are occasionally observed. Clumps of robust hydroids such as Tubularia indivisa, Nemertesia antennina, Hydrallmania falcata and Halecium halecinum may also be observed. Other species which may be present include the polychaete Spirobranchus triqueter, Balanus crenatus, Asterias rubens, Pagurus bernhardus and Steromphala cineraria. Occasionally, sponges such as Haliclona oculata and Halichondria panicea, and ascidians such as Dendrodoa grossularia may also be observed.


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
Sabellaria spinulosa 22 Abundant 81-100%
Urticina felina 9 Occasional 81-100%
Balanus crenatus 6 Frequent 61-80%
Spirobranchus triqueter 6 Frequent 41-60%
Flustra foliacea 5 Occasional 61-80%
Asterias rubens 4 Occasional 61-80%
Dendrodoa grossularia 4 Frequent 61-80%
Tubularia indivisa 4 Occasional 61-80%
Alcyonidium diaphanum 3 Occasional 61-80%
Bicellariella ciliata 3 Frequent 41-60%
Halichondria panicea 3 Frequent 41-60%
Pagurus 3 Occasional 81-100%
Buccinum undatum 2 Rare 61-80%
Crisularia plumosa 2 Frequent 21-40%
Haliclona oculata 2 Occasional 41-60%
Hydrallmania falcata 2 Occasional 41-60%
Nemertesia antennina 2 Occasional 41-60%
Vesicularia spinosa 2 Occasional 21-40%
Steromphala cineraria 1 Occasional 21-40%
Halecium halecinum 1 Frequent 21-40%

Similar biotopes or habitat types

This biotope is found on the upper faces of moderately exposed, moderately tide-swept circalittoral bedrock, boulders and cobbles. This biotope is similar in that the polychaete S. spinulosa is the prevalent species. However, it is distinguished from CR.MCR.CSab.Sspi.ByB by a dense turf of didemnid, and other colonial ascidians such as Polycarpa sp.

This biotope is found on circalittoral mixed sediment, not rock or mixed substrata in the case of CR.MCR.CSab.Sspi.ByB.

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