Biodiversity & Conservation

Mytilus edulis beds with hydroids and ascidians on tide-swept moderately exposed circalittoral rock

CR.MCR.M.MytHAs


MCR.MytHAs

Image Anon. - Mytilus edulis beds with hydroids and ascidians on tide-swept moderately exposed circalittoral rock. Image width ca 1m in foreground.
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Distribution map

CR.MCR.M.MytHAs recorded (dark blue bullet) and expected (light blue bullet) distribution in Britain and Ireland (see below)


  • EC_Habitats

Recorded distribution in Britain and Ireland

The biotope has a restricted distribution around the UK. It has been described in surveys of Flamborough Head, Selsey Bill to Beachy Head, the Lizard, Skomer, the Lleyn Peninsula, the Menai Straits, Anglesey, Liverpool Bay, and Jura & Islay, west Scotland. It is also known to occur off the Gower Peninsula and in localized areas of Plymouth Sound.

Habitat preferences

Temperature range preferences - See additional information.

Water clarity preferences - Medium clarity / Medium turbidity
Low clarity / High turbidity

Limiting Nutrients - Data deficient

Other preferences -

Additional information

Mytilus edulis is found in circumpolar and temperature waters in the north and south hemispheres. Mytilus edulis can survive periodic freezing to -10°C for short periods (e.g. -16°C for 24hrs). In British waters an upper sustained thermal tolerance limit of 29°C has been reported (Holt et al., 1998).


This review can be cited as follows:

Tyler-Walters, H. 2001. Mytilus edulis beds with hydroids and ascidians on tide-swept moderately exposed circalittoral rock. Marine Life Information Network: Biology and Sensitivity Key Information Sub-programme [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 24/07/2014]. Available from: <http://www.marlin.ac.uk/habitatpreferences.php?habitatid=208&code=1997>