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Marine Habitat Classification

Description of biotope or habitat type

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   Mixed Laminaria hyperborea and Laminaria saccharina park on sheltered lower infralittoral rock

Physical habitat description

Salinity Full (30-35 ppt)
Wave exposure Sheltered, Very sheltered
Tidal streams Weak (>1 kn)
Substratum Bedrock; boulders
Zone Infralittoral - lower
Depth Band 5-10 m, 10-20 m
Other Features Siltation

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 IR.LIR.K.LhypLsac.Pk Mixed <I>Laminaria hyperborea</I> and <I>Laminaria saccharina</I> park on sheltered lower infralittoral rock

  • 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.


Sheltered silted, bedrock and boulders with a park of mixed Laminaria hyperborea and Laminaria saccharina. Both kelp species are sparse in the park (Frequent). Beneath the often 'cape-form' kelp canopy, foliose red seaweeds such as Delesseria sanguinea, Cryptopleura ramosa, Heterosiphonia plumosa and Brongniartella byssoides are often present at high densities on the silted rock. Other red seaweeds such as encrusting coralline algae, Phycodrys rubens, Callophyllis laciniata, Bonnemaisonia asparagoides and Plocamium cartilagineum can be present. Other brown seaweeds include Dictyota dichotoma and Desmarestia aculeata. The animal component of this biotope is generally richer than the upper infralittoral mixed kelp forest (LhypLsac.Ft). A variety of hydroids such as Obelia geniculata grow epiphytically on the kelp fronds along with the bryozoan Membranipora membranacea. The echinoderm Antedon bifida and ascidians such as Clavelina lepadiformis attach to the kelp stipes, above the silted rock. The rock itself supports anthozoans such as Caryophyllia smithii and Urticina felina as well as the tube-building polychaete Pomatoceros triqueter and the crap Necora puber. Grazers include the prominent echinoderm Echinus esculentus and the gastropods Gibbula cineraria and Calliostoma zizyphinum. Where pockets of sediment occur, there may be an increase in infaunal species such as the burrowing anthozoan Cerianthus lloydii, the brittlestar Ophiura albida, and starfish Asterias rubens. Although there is a decrease in the number of algal species in the kelp park, the abundance remains relatively high.


These mixed kelp parks are generally found below the mixed kelp forest (LhypLsac.Ft) where there is a continuation of suitable hard substrata present. These sheltered kelps are also frequently found on bedrock or boulder exposures (XFa) adjacent to sediment seabed characterised by infaunal species. Where silted, circalittoral rock occurs below the kelp park a variety of biotopes may be found characterised by varying amounts of featherstars, anthozoans, solitary ascidians and sponge communities (e.g. AntAsH, LgAsSp, AmenCio, NeoPro and ModHAs).

Temporal variation


Characterising species

Taxon Relative importance of taxon for defining this community (%) Typical abundance - SACFOR scale % of core records where taxon was recorded
Obelia geniculata 2 Frequent 41-60 %
Urticina felina 1 Occasional 21-40 %
Caryophyllia smithii 1 Occasional 41-60 %
Pomatoceros triqueter 4 Frequent 41-60 %
Necora puber 2 Occasional 41-60 %
Gibbula cineraria 3 Frequent 41-60 %
Calliostoma zizyphinum 2 Occasional 41-60 %
Membranipora membranacea 1 Frequent 21-40 %
Antedon bifida 1 Frequent 21-40 %
Asterias rubens 5 Occasional 61-80 %
Echinus esculentus 7 Frequent 61-80 %
Clavelina lepadiformis 1 Occasional 41-60 %
Bonnemaisonia asparagoides 2 Occasional 41-60 %
Corallinaceae 3 Frequent 41-60 %
Rhodophyllis divaricata 1 Occasional 21-40 %
Callophyllis laciniata 2 Occasional 41-60 %
Plocamium cartilagineum 4 Occasional 61-80 %
Heterosiphonia plumosa 2 Occasional 41-60 %
Cryptopleura ramosa 1 Occasional 41-60 %
Delesseria sanguinea 5 Occasional 61-80 %
Phycodrys rubens 1 Occasional 21-40 %
Brongniartella byssoides 1 Frequent 21-40 %
Dictyota dichotoma 3 Frequent 61-80 %
Desmarestia aculeata 2 Occasional 41-60 %
Laminaria hyperborea 14 Frequent 81-100 %
Laminaria saccharina 6 Frequent 61-80 %

Similar biotopes or habitat types

Found in shallower water, above the kelp park where both kelp species and red seaweeds occur in greater abundance. The fauna is generally less diverse in the forest than in the park.

Found in shallower water above the kelp park, but this biotope has a lower abundance of foliose red seaweeds due to the presence of more grazing echinoderms. The kelps L. hyperborea and L. saccharina has a typically abundance of Common.

Generally occurs in more sheltered, siltier conditions and lacks L. hyperborea

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