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Marine Habitat Classification

Description of biotope or habitat type

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   Low energy circalittoral rock

Physical habitat description

Salinity Full (30-35 ppt), Reduced (18-30ppt)
Wave exposure Sheltered, Very sheltered
Tidal streams Weak (>1 kn), Very weak (negligible)
Substratum Bedrock, boulders
Zone Circalittoral - lower, Circalittoral - upper
Depth Band 5-10 m, 10-20 m, 20-30 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.LCR Low energy 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 habitat complex occurs on wave-sheltered circalittoral bedrock and boulders subject to mainly weak/very weak tidal streams. The biotopes identified within this habitat complex are often dominated by encrusting red algae, brachiopods (Novocrania anomala) and ascidians (Ciona intestinalis and Ascidia mentula). Two fouling biotopes have also been identified: Aasp has been recorded from disused fishing nets and other artificial substrata, and is characterised by aggregations of Ascidiella aspersa whilst AdigMsen has been recorded from steel wrecks, and is characterised by dense aggregations of Alcyonium digitatum and Metridium senile. The LgAsSp biotope is characteristic of the wave-sheltered conditions found in the Kenmare River on the west coast of Ireland.


No situation data available.

Temporal variation

No temporal variation data available.

Characterising species

Characterising species data not applicable.

Similar biotopes or habitat types

Not applicable or unknown.

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