Description of biotope or habitat type
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Kelp in variable or reduced salinity
Physical habitat description
Salinity | Full (30-35 ppt), Reduced (18-30ppt), Variable (18-35 ppt), Low (<18ppt) |
---|---|
Wave exposure | Sheltered, Very sheltered, Extremely sheltered |
Tidal streams | Weak (>1 kn), Very weak (negligible) |
Substratum | Bedrock, boulders & cobbles |
Zone | Infralittoral, Sublittoral fringe |
Depth Band | 0-5 m, 5-10 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
Very wave-sheltered bedrock, boulders and cobbles subject to only weak tidal streams in the sublittoral fringe and infralittoral zone, in areas of variable/reduced salinity. This biotope complex is characterised by the kelp Saccharina latissima and coralline crusts such as Lithothamnion glaciale. Grazers such as the urchins Psammechinus miliaris and Echinus esculentus, and the gastropods Steromphala cineraria and Buccinum undatum may be present. The tube-dwelling polychaete Spirobranchus triqueter, the ascidians Ciona intestinalis, Corella parallelogramma and Ascidiella scabra, the barnacle Balanus crenatus, the starfish Asterias rubens and the brittlestar Ophiothrix fragilis may also be present. Red algal communities are composed primarily of Phycodrys rubens. The crabs Carcinus maenas and Pagurus bernhardus, and the bivalve Modiolus modiolus may also be observed.
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 |
---|---|---|---|
Psammechinus miliaris | 12 | Frequent | 61-80% |
Spirobranchus triqueter | 10 | Frequent | 61-80% |
Corallinaceae | 7 | Common | 41-60% |
Asterias rubens | 7 | Frequent | 61-80% |
Carcinus maenas | 4 | Occasional | 61-80% |
Phycodrys rubens | 4 | Occasional | 41-60% |
Lithothamnion glaciale | 3 | Common | 21-40% |
Pagurus bernhardus | 3 | Occasional | 41-60% |
Buccinum undatum | 2 | Occasional | 41-60% |
Ciona intestinalis | 2 | Occasional | 41-60% |
Corella parallelogramma | 2 | Occasional | 21-40% |
Steromphala cineraria | 2 | Frequent | 21-40% |
Ophiothrix fragilis | 2 | Frequent | 21-40% |
Echinus esculentus | 2 | Occasional | 21-40% |
Ascidiella scabra | 1 | Occasional | 21-40% |
Balanus crenatus | 1 | Occasional | 21-40% |
Modiolus modiolus | 1 | Occasional | 21-40% |
Similar biotopes or habitat types
Not applicable or unknown.