Marine Atlantic infralittoral muddy sand

This habitat is typically on a substrate of non-cohesive muddy sand (with 5% to 20% silt/clay). It occurs in the infralittoral zone, extending from the extreme lower shore down to more stable circalittoral zone at about 15-20 m. The habitat develops on sheltered shores in fully marine conditions, or occasionally in areas subject to variable salinity. The habitat supports a variety of animal-dominated communities, particularly polychaetes,  bivalves and the urchin Echinocardium cordatum depending on the sediment characteristics and the degree of shelter.  In stable, fine, compacted sands and slightly muddy sands in the infralittoral and littoral fringe, communities occur that are dominated by venerid bivalves. 

Indicators of quality:

Both biotic and abiotic indicators have been used to describe marine habitat quality. These include: the presence of characteristic species as well as those which are sensitive to the pressures the habitat may face; water quality parameters; levels of exposure to particular pressure, and more integrated indices which describe habitat structure and function, such as trophic index, or successional stages of development in habitats that have a natural cycle of change over time.

There are no commonly agreed indicators of quality for this habitat, although particular parameters may have been set in certain situations e.g. protected features within Natura 2000 sites, where reference values have been determined and applied on a location-specific basis.

Synthesis of Red List assessment

Confidence in the assessment

Pressures and threats