Description of biotope or habitat type
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Laminaria digitata on moderately exposed sublittoral fringe bedrock
Physical habitat description
| Salinity | Full (30-35 ppt) |
|---|---|
| Wave exposure | Exposed, Moderately exposed, Sheltered |
| Tidal streams | Moderately strong (1-3 kn), Weak (>1 kn), Very weak (negligible) |
| Substratum | Bedrock; boulders |
| Zone | Sublittoral fringe |
| Depth Band | 0-5 m, Lower shore |
| 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
Exposed to sheltered sublittoral fringe bedrock dominated by a dense canopy of Laminaria digitata, often with a wide range of filamentous and foliose red seaweeds beneath. The most frequently occurring red seaweeds are Palmaria palmata, Corallina officinalis, Mastocarpus stellatus, Chondrus crispus, Lomentaria articulata and Membranoptera alata. Generally the rocky substratum is covered by encrusting coralline algae, on which occasional limpets Patella vulgata and topshells Steromphala cineraria graze. A wide variety of fauna occurs, some of the most commonly occurring species being the sponge Halichondria panicea and the tube-building polychaete Spirobranchus triqueter. Kelp holdfasts provide a refuge for a varied assemblage of species such as sponges and the limpet Patella pellucida, while encrusting bryozoans such as Electra pilosa more often are found on the fronds of foliose red seaweeds. Solitary ascidians may be locally abundant where overhanging or vertical rock occurs, while the hydroid Dynamena pumila can be abundant on Fucus serratus and Laminaria sp. fronds. On exposed, wave-surged shores, the robust red seaweeds M. stellatus, C. crispus and C. officinalis can form a dense turf beneath the kelp along with the occasional green seaweed Ulva lactuca. Similarly on such shores the mussel Mytilus edulis can occur in extremely dense aggregations on the rock, beneath the kelp canopy.
Situation
This biotope is usually found on the extreme low shore below the Fucus serratus zone (Fser) and above the truly sublittoral Laminaria hyperborea zone (Lhyp).
Temporal variation
Unknown
Characterising species
| Taxon | Relative importance of taxon for defining this community (%) | Typical abundance - SACFOR scale | % of core records where taxon was recorded |
|---|---|---|---|
| Laminaria digitata | 29 | Abundant | 81-100% |
| Corallinaceae | 13 | Abundant | 61-80% |
| Palmaria palmata | 5 | Frequent | 61-80% |
| Chondrus crispus | 4 | Frequent | 61-80% |
| Corallina officinalis | 4 | Occasional | 41-60% |
| Mastocarpus stellatus | 4 | Frequent | 41-60% |
| Electra pilosa | 3 | Occasional | 41-60% |
| Fucus serratus | 3 | Occasional | 41-60% |
| Halichondria panicea | 3 | Occasional | 41-60% |
| Steromphala cineraria | 2 | Occasional | 41-60% |
| Membranoptera alata | 2 | Occasional | 41-60% |
| Patella vulgata | 2 | Occasional | 21-40% |
| Dynamena pumila | 1 | Occasional | 21-40% |
| Patella pellucida | 1 | Occasional | 21-40% |
| Lomentaria articulata | 1 | Occasional | 21-40% |
| Mytilus edulis | 1 | Occasional | 21-40% |
| Spirobranchus triqueter | 1 | Occasional | 41-60% |
| Ulva lactuca | 1 | Occasional | 21-40% |
Similar biotopes or habitat types
IR.HIR.KFaR.Ala.Ldig
Alaria esculenta is generally at least Common in this biotope and/or of similar abundance to L. digitata, with dense mussels and barnacles overgrowing coralline-encrusted rock.
IR.MIR.KR.Ldig.Bo
L. digitata on moderately exposed boulder shores and occasionally on exposed or sheltered shores. Other canopy-forming kelps such as A. esculenta and Saccharina latissima are not present in this biotope.
IR.MIR.KR.Ldig.Pid
L. digitata and rock-boring animals such as piddocks (Barnea candida, Pholas dactylus and Petricolaria pholadiformis), the bivalve Hiatella arctica and worms Polydora spp. on soft littoral fringe rock.
IR.MIR.KR.Ldig.Ldig
S. latissima and L. digitata generally occur in equal abundance on silted, sheltered rock. Kelps often 'cape-form'. Fewer faunal species and fewer red seaweeds is present, but Chorda filum often present.Classification history of this biotope or habitat type
| Classification version | Code |
|---|---|
| 1995 | LRK.LDIG.LDIG |
