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Marine Habitat Classification

Description of biotope or habitat type

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   Laminaria saccharina and robust red algae on infralittoral gravel and pebbles

Physical habitat description

Salinity Full (30-35 ppt)
Wave exposure Moderately exposed, Sheltered, Very sheltered
Tidal streams Moderately strong (1-3 kn), Weak (>1 kn), Very weak (negligible)
Substratum Gravel and coarse sand with some pebbles
Zone Infralittoral
Depth Band 0-5 m, 5-10 m, 10-20 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.

Distribution of habitat SS.SMp.KSwSS.LsacR.Gv <I>Laminaria saccharina</I> and robust red algae on infralittoral gravel and pebbles

  • 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.


Shallow kelp community found on gravel and gravelly sand in slightly less exposed areas than SMP.LsacR.CbPb but in moderately strong tidal currents, and characterised by occasional Laminaria saccharina with an undergrowth of robust red seaweeds. Characteristic red seaweeds, as with LsacR.CbPb, include Plocamium cartilagineum, Halarachnion ligulatum and Brongniartella byssoides; however the greater stability of this biotope allows a slightly more diverse range of red seaweeds to become established including Polyides rotundus, Rhodophyllis divaricata, Delesseria sanguinea and Nitophyllum punctatum. Coralline encrusting algae may be found covering the larger pebbles. Laminaria hyperborea may also be present within this biotope, although at low densities. Other brown algal species present include Desmarestia spp., Dictyota dichotoma and Chorda filum, all at low abundance. The ubiquitous green seaweed Ulva sp. may be found attached to larger pebbles.


No situation data available.

Temporal variation

No temporal data available.

Characterising species

Taxon Relative importance of taxon for defining this community (%) Typical abundance - SACFOR scale % of core records where taxon was recorded
Cerianthus lloydii 1 Occasional 21-40 %
Pomatoceros triqueter 1 Occasional 21-40 %
Pagurus bernhardus 3 Occasional 41-60 %
Gibbula cineraria 1 Occasional 21-40 %
Asterias rubens 4 Occasional 41-60 %
Bonnemaisonia asparagoides 2 Occasional 41-60 %
Corallinaceae 3 Occasional 41-60 %
Cystoclonium purpureum 1 Occasional 21-40 %
Rhodophyllis divaricata 2 Occasional 41-60 %
Dilsea carnosa 1 Occasional 41-60 %
Halarachnion ligulatum 2 Occasional 41-60 %
Callophyllis laciniata 1 Occasional 21-40 %
Phyllophora crispa 1 Occasional 21-40 %
Polyides rotundus 2 Occasional 41-60 %
Gracilaria gracilis 2 Occasional 21-40 %
Plocamium cartilagineum 5 Occasional 61-80 %
Chylocladia verticillata 1 Occasional 21-40 %
Lomentaria clavellosa 1 Occasional 41-60 %
Pterothamnion plumula 1 Occasional 21-40 %
Cryptopleura ramosa 1 Occasional 21-40 %
Delesseria sanguinea 3 Occasional 41-60 %
Hypoglossum hypoglossoides 2 Occasional 21-40 %
Nitophyllum punctatum 2 Occasional 41-60 %
Phycodrys rubens 1 Occasional 21-40 %
Brongniartella byssoides 2 Occasional 41-60 %
Polysiphonia elongata 1 Occasional 21-40 %
Rhodomela confervoides 1 Occasional 21-40 %
Trailliella intricata 1 Frequent 21-40 %
Dictyota dichotoma 3 Occasional 41-60 %
Desmarestia aculeata 2 Occasional 41-60 %
Desmarestia viridis 2 Occasional 41-60 %
Chorda filum 2 Occasional 21-40 %
Laminaria hyperborea 2 Occasional 41-60 %
Laminaria saccharina 10 Occasional 81-100 %
Ulva 5 Occasional 61-80 %

Similar biotopes or habitat types

LsacR.CbPb has a less dense covering of L. saccharina, with a less diverse, more robust red algal community.

Similar in species composition but differ in sediment characteristics and consequently infaunal species composition.

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