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Marine Habitat Classification

Description of biotope or habitat type

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   Saccharina latissima park on very sheltered lower infralittoral rock

Physical habitat description

Salinity Full (30-35 ppt)
Wave exposure Sheltered, Very sheltered
Tidal streams Weak (>1 kn), Very weak (negligible)
Substratum Bedrock; boulders and cobbles
Zone Infralittoral - lower
Depth Band 5-10 m, 10-20 m
Other Features Also on vertical rock.

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.SLat.Pk <I>Saccharina latissima</I> park on very 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.


Silty bedrock or boulders with a Saccharina latissima park (often the cape-form). Beneath the canopy, the rock is covered by encrusting coralline algae, and the urchin Echinus esculentus is often present. Due to the amount of silt cover on the rock and the reduced light intensity beneath the broad-fronded kelp, only a few red seaweeds typically survive, the most common species being Phycodrys rubens, Delesseria sanguinea, Bonnemaisonia spp. and Vertebrata byssoides. The brown seaweeds Dictyota dichotoma and Cutleria multifida may be present in low abundance. Compared to the kelp forest zone above (Lsac.Ft) both the kelp and other seaweeds are sparse (Occasional). The most conspicuous animals are large solitary ascidians, particularly Ascidia mentula and Ciona intestinalis, together with the smaller Clavelina lepadiformis. In general, the faunal component of this biotope is similar to other sheltered kelp biotopes and includes a variety of mobile crustaceans such Carcinus maenas and Pagurus bernhardus, the keelworm Spirobranchus spp., terebellid worms, echinoderms Asterias rubens, Ophiothrix fragilis and the featherstar Antedon bifida. The hydroid Kirchenpauria pinnata, although only rare is often found in the kelp park along with the top shell Steromphala cineraria and the barnacle Balanus crenatus.


L. saccharina park can be found below a similar forest (Lsac.Ft) where suitable hard substrata exist or on isolated rock exposures surrounded by sediment communities. It may also occur below a zone of mixed Laminaria hyperborea and L. saccharina forest (LhypLsac). L. saccharina can also form a band below L. hyperborea forest (Lhyp.Ft) where some shelter from wave-action is afforded with depth (L. saccharina is not tolerant of surge), or more likely where L. hyperborea has been grazed out (below Lhyp.GzFt) since L. saccharina grows far quicker than L. hyperborea. Where such a narrow band occurs it is generally less silted than that found below Lsac.Ft in much more sheltered conditions. A range of sheltered circalittoral biotopes may occur on any deeper rock below (e.g. AntAsH, AmenCio 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
Saccharina latissima 18 Occasional 81-100%
Corallinaceae 9 Frequent 61-80%
Echinus esculentus 8 Occasional 61-80%
Asterias rubens 6 Occasional 61-80%
Ascidia mentula 5 Occasional 41-60%
Pagurus bernhardus 4 Occasional 41-60%
Spirobranchus triqueter 3 Frequent 41-60%
Antedon bifida 2 Occasional 21-40%
Bonnemaisonia hamifera 2 Common 21-40%
Vertebrata byssoides 2 Occasional 21-40%
Clavelina lepadiformis 2 Occasional 21-40%
Delesseria sanguinea 2 Occasional 21-40%
Dictyota dichotoma 2 Occasional 21-40%
Steromphala cineraria 2 Occasional 41-60%
Ophiothrix fragilis 2 Occasional 41-60%
Phycodrys rubens 2 Frequent 21-40%
Balanus crenatus 1 Frequent 21-40%
Bonnemaisonia asparagoides 1 Occasional 21-40%
Carcinus maenas 1 Occasional 21-40%
Caryophyllia smithii 1 Occasional 21-40%
Ciona intestinalis 1 Occasional 21-40%
Cutleria multifida 1 Frequent 21-40%
Kirchenpaueria pinnata 1 Occasional 21-40%
Seraphsidae 1 Occasional 21-40%

Similar biotopes or habitat types

S. latissima and L. hyperborea co-dominantes this biotope (both Frequent). Generally less silted than IR.LIR.K.Slat.Pk and there tends to be a greater variety of species, particularly more red seaweeds.

Occurs in shallower water where S. latissima is typically Abundant and there is a greater variety and higher abundance of red seaweeds.

This biotope is very impoverished even compared to IR.LIR.K.Slat.Pk and the kelp may be absent altogether. The diversity of red seaweeds are much lower than in the park with a dominance of Corallinacea (Common) even though small turf of foliose red seaweeds and brown seaweeds like Desmarestia spp. and Chorda filum may occur. Halichondria panicea (Rare) is the likely to be only sponge present compared to IR.LIR.K.Slat.Pk, which have a higher diversity of sponges (Porifera).

Classification history of this biotope or habitat type

Classification version Code
2015 (15.03) IR.LIR.K.Lsac.Pk

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