Biodiversity & Conservation

Laminaria digitata, ascidians and bryozoans on tide-swept sublittoral fringe rock


<i>%Laminaria digitata%</i>, ascidians and bryozoans on tide-swept sublittoral fringe rock
Distribution map

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

  • UK_BAP

Marine natural heritage importance

Listed under UK Biodiversity Action Plan
National importance Scarce
Habitat Directive feature (Annex 1) Reefs
Large shallow inlets and bays

Biotope importance

The fauna associated with the holdfasts of Laminaria digitata are known to be highly diverse (Birkett et al., 1998) and may provide an important refuge for juveniles of some larger species or commercial species.


Laminaria digitata cast up on the shore have historically been collected and used for fertilizer. More recently Laminaria digitata has been cultivated commercially for alginate in Britain and, in Ireland and France, it is cultivated as a sea vegetable. This kelp is also used in the pharmaceutical industry and as an active ingredient in 'beauty products'. Dulse Palmaria palmata is used as a vegetable substitute or animal fodder although harvesting on a commercial scale only takes place in Ireland and in France. The coral weed Corallina officinalis is collected for medical purposes; the fronds are dried and converted to hydroxyapatite and used as bone forming material (Ewers et al., 1987). It is also sold as a powder for use in the cosmetic industry. A European research proposal for cultivation of Corallina officinalis is pending (Dr T. Wiedemann, pers. comm.).

Additional information icon Additional information

This review can be cited as follows:

Marshall, C.E. 2005. Laminaria digitata, ascidians and bryozoans on tide-swept 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 26/11/2015]. Available from: <>