Biodiversity & Conservation

Laminaria digitata on moderately exposed sublittoral fringe rock



Image Keith Hiscock - Kelp forest exposed at low tide with rocky shore in background. Image width ca 3 m (foreground).
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Distribution map

IR.MIR.KR.Ldig.Ldig recorded (dark blue bullet) and expected (light blue bullet) distribution in Britain and Ireland (see below)

  • EC_Habitats

Text page icon Habitat description

Map icon Distribution of biotope in Britain and Ireland Recorded from most coasts around Britain. Scarce along east coast of England, particularly between Ouse and Thames estuaries, due to turbidity and lack of hard substrata. No records from the east coast of Scotland but no doubt present.
National importance Widespread

Text page icon Description of biotope

For a full description of this biotope including characterizing species, distribution, survey information and references visit JNCC

Moderately exposed to sheltered sublittoral fringe bedrock or boulders dominated by a dense canopy of Laminaria digitata often with a wide range of filamentous and foliose red seaweeds beneath. The rocky substratum is usually covered by encrusting coralline algae, on which occasional limpets Patella spp. and top shells Gibbula spp. graze. A wide variety of fauna occurs, including the sponge Halichondria panicea, barnacles (Balanus crenatus and Semibalanus balanoides) and occasional small mussels Mytilus edulis. Kelp holdfasts provide a refuge for a varied assemblage of species including sponges (e.g. Leucosolenia spp.), anemones (Urticina felina), limpets (Helcion pellucidum), crustaceans, encrusting bryozoans and colonial ascidians. This biotope is usually found beneath the Fucus serratus zone (MLR.Fser) and above the truly sublittoral Laminaria hyperborea zone (MIR.Lhyp). Other canopy-forming kelps such as Alaria esculenta and Laminaria saccharina, may occur although never at high abundance (compare with EIR.Ala.Ldig and SIR.Lsac.Ldig respectively). In areas where tidal water movement is increased, a richer L. digitata-dominated biotope (MIR.Ldig.T) generally replaces the sheltered shore Laminaria saccharina (SIR.Lsac) biotope. (Information taken from the Marine Biotope Classification for Britain and Ireland, Version 97.06: Connor et al., 1997a, b).

Additional information icon Additional information

This review can be cited as follows:

Hill, J.M. 2000. Laminaria digitata on moderately exposed sublittoral fringe rock. Marine Life Information Network: Biology and Sensitivity Key Information Sub-programme [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 27/11/2015]. Available from: <>