Description of biotope or habitat type
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Grazed Saccharina latissima with Echinus, brittlestars and coralline crusts on sheltered infralittoral rock
Physical habitat description
| Salinity | Variable (18-35 ppt) |
|---|---|
| Wave exposure | Very sheltered |
| Tidal streams | Weak (>1 kn), Very weak (negligible) |
| Substratum | Bedrock & boulders |
| Zone | Infralittoral - upper, 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
Coralline encrusted rock with scattered tufts of red seaweed and a relatively high abundance of grazing echinoderms which typically include the urchin Echinus esculentus and/or the brittlestars Ophiothrix fragilis or Ophiocomina nigra. The rock often looks bare, with few conspicuous species present although Saccharina latissima may occur it is generally in low abundance (Rare or Occasional). The red seaweeds, reduced to small tufts through grazing, include Phycodrys rubens, Delesseria sanguinea and Vertebrata byssoides and although these seaweeds also occur in Lsac.Pk they are far less frequent in this biotope. Brown seaweeds, such as Desmarestia viridis, Chorda filum and Cutleria multifida, may be present. Grazing molluscs, such as Steromphala cineraria and can be common. Under-boulder habitats can harbour the crabs Necora puber and Pagurus bernhardus, terebellid polychaetes and the polychaete Spirobranchus spp. with ascidians Ascidia mentula. and Clavelina lepadiformis on the open rock along with the echinoderm Asterias rubens and the hydroids Kirchenpauria pinnata and Obelia dichotoma.
Situation
This biotope generally occurs on rock below a dense kelp forest of L. saccharina (Lsac.Ft) or mixed kelp (LhypLsac.Ft).
Temporal variation
If the grazing pressure is reduced (i.e. a decrease in the number of grazing echinoderms present) a richer kelp community may develop (Lsac.Pk or LhypLsac.Pk).
Characterising species
| Taxon | Relative importance of taxon for defining this community (%) | Typical abundance - SACFOR scale | % of core records where taxon was recorded |
|---|---|---|---|
| Corallinaceae | 12 | Common | 61-80% |
| Saccharina latissima | 12 | Occasional | 81-100% |
| Echinus esculentus | 11 | Occasional | 81-100% |
| Spirobranchus | 9 | Frequent | 41-60% |
| Asterias rubens | 6 | Occasional | 61-80% |
| Steromphala cineraria | 5 | Occasional | 41-60% |
| Ophiothrix fragilis | 4 | Rare | 41-60% |
| Phycodrys rubens | 4 | Rare | 41-60% |
| Ascidia mentula | 3 | 41-60% | |
| Kirchenpaueria pinnata | 3 | 41-60% | |
| Ophiocomina nigra | 3 | 41-60% | |
| Pagurus bernhardus | 3 | Occasional | 41-60% |
| Vertebrata byssoides | 2 | 21-40% | |
| Chorda filum | 2 | 41-60% | |
| Delesseria sanguinea | 2 | 21-40% | |
| Necora puber | 2 | Rare | 41-60% |
| Obelia dichotoma | 2 | 21-40% | |
| Cutleria multifida | 1 | Frequent | 21-40% |
| Desmarestia viridis | 1 | Occasional | 21-40% |
| Filamentous red algae | 1 | 21-40% | |
| Seraphsidae | 1 | Rare | 41-60% |
Similar biotopes or habitat types
IR.LIR.K.SLat.Pk
This biotope a higher diversity and abundance of red seaweeds. IR.LIR.K.Slat.Pk also have a notable presence of sponges (Porifera), which are usually absent in IR.LIR.K.Slat.Gz.
CR.MCR.EcCr.FaAlCr
Occurs in deeper more exposed sites and has a similar grazed crustose appearance but lacks the red and brown seaweeds of IR.LIR.K.Slat.Gz.Classification history of this biotope or habitat type
| Classification version | Code |
|---|---|
| 2015 (15.03) | IR.LIR.K.Lsac.Gz |