Biodiversity & Conservation

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

Soft rock, such as chalk, in the sublittoral fringe characterized by Laminaria digitata and rock-boring animals such as piddocks (Barnea candida, Pholas dactylus and Petricola pholadiformis), the bivalve Hiatella arctica and worms Polydora spp. Beneath the kelp forest, a wide variety of red seaweeds, including Corallina officinalis, Palmaria palmata, Chondrus crispus, Membranoptera alata and Halurus flosculosus, may occur. Empty piddock burrows are often colonised by the anemones Sagartia elegans or by the sand-tube building worm Sabellaria spinulosa. The undersides of small chalk boulders are colonised by encrusting bryozoans, colonial ascidians and the keel worm Pomatoceros lamarcki. The boulders and any crevices within the chalk provide a refuge for small crustaceans such as Carcinus maenas, young Cancer pagurus, Pagurus bernhardus and Porcellana platycheles. (Information taken from the Marine Biotope Classification for Britain and Ireland, Version 97.06: Connor et al., 1997a, b).