Description of biotope or habitat type
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Soft rock communities
Physical habitat description
| Salinity | Full (30-35 ppt) |
|---|---|
| Wave exposure | Moderately exposed |
| Tidal streams | Moderately strong (1-3 kn) |
| Substratum | Bedrock |
| Zone | Circalittoral - upper |
| Depth Band | 0-5 m, 5-10 m, 10-20 m |
| Other Features | Soft rock |
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 biotope complex occurs on moderately wave-exposed, circalittoral soft bedrock subject to moderately strong tidal streams. As this complex is found in highly turbid water conditions, the circalittoral zone may begin at the low water mark, due to poor light penetration. This complex is dominated by the piddock Pholas dactylus. Other species typical of this complex include the polychaete Polydora and Bispira volutacornis, the sponges Cliona celata and Suberites ficus, the bryozoan Flustra foliacea, Alcyonium digitatum, the starfish Asterias rubens, the mussel Mytilus edulis and the crab Necora puber and Cancer pagurus. Foliose red algae may also be present. Three biotopes have been identified within this complex: Pid, Pol and Hia. Please note: in areas subject to very high turbidity, biotopes within this biotope complex may occur in the infralittoral and even the littoral zone.
Situation
No situation data available.
Temporal variation
No temporal variation data available.
Characterising species
| Taxon | Relative importance of taxon for defining this community (%) | Typical abundance - SACFOR scale | % of core records where taxon was recorded |
|---|---|---|---|
| Pholas dactylus | 68 | Common | 61-80% |
| Polydora | 4 | Abundant | 21-40% |
| Cliona celata | 3 | Occasional | 21-40% |
| Foliose red algae | 3 | Occasional | 21-40% |
| Alcyonium digitatum | 2 | Occasional | 21-40% |
| Asterias rubens | 2 | Occasional | 21-40% |
| Flustra foliacea | 2 | Occasional | 21-40% |
| Mytilus edulis | 2 | Common | 1-20% |
| Suberites ficus | 2 | Frequent | 1-20% |
| Bispira volutacornis | 1 | Occasional | 1-20% |
| Cancer pagurus | 1 | Occasional | 21-40% |
| Necora puber | 1 | Occasional | 21-40% |
Similar biotopes or habitat types
Not applicable or unknown.
Classification history of this biotope or habitat type
| Classification version | Code |
|---|---|
| 1997 (97.06) | CR.MCR.SfR |