Atlantic silted kelp on marine low energy infralittoral rock

This habitat can be found in wave and tide-sheltered conditions with Laminaria hyperborea and/or Saccharina latissima on infralittoral bedrock and boulders.  It is typically subject to weak tidal streams and rather silty conditions. The associated seaweeds are silt-tolerant and include a high proportion of delicate filamentous types. Beneath the kelp canopy, the faunal component is generally less diverse than in kelp forests that develop in more exposed locations. Some areas, particularly in the lower infralittoral zone, are subject to intense grazing by urchins and chitons and subsequently may have poorly developed seaweed communities. In very sheltered conditions S.latissima may grow as a ‘cape form’ where there are often few associated seaweeds due to siltation, grazing or shading from the dense kelp canopy.

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