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.

- 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.
Description
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.
Situation
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.