Description of biotope or habitat type
Low energy littoral rock
Habitat (physical) description
|Salinity||Full (30-35 ppt), Reduced (18-30ppt), Variable (18-35 ppt), Low (<18ppt)|
|Wave exposure||Sheltered, Very sheltered, Extremely sheltered|
|Tidal streams||Weak (>1 kn), Very weak (negligible)|
|Substratum||Bedrock, boulders, cobbles and pebbles, mixed substrata on sand and mud|
|Depth Band||Lower shore, Mid shore, Upper shore|
Download comparative physical and biological data. The comparative tables enable a rapid comparison of the species composition and principal physical characteristics between a given set of biotopes.
- Records used to define the biotope (core records)
- Other records assigned to this biotope, marked as 'certain'
- Other records assigned to this biotope, marked as 'uncertain'
Point data based on records in the UK Marine Recorder Snapshot.
Sheltered to extremely sheltered rocky shores with very weak to weak tidal streams are typically characterised by a dense cover of fucoid seaweeds which form distinct zones (the wrack Pelvetia canaliculata on the upper shore through to the wrack Fucus serratus on the lower shore). Where salinity is reduced (such as at the head of a sea loch or where streams run across the shore) Fucus ceranoides may occur. Fucoids also occur on less stable, mixed substrata (cobbles and pebbles on sediment) although in lower abundance and with fewer associated epifaunal species; beds of mussels Mytilus edulis are also common. In summer months, dense blankets of ephemeral green and red seaweeds can dominate these mixed shores. Two biotope complexes have been described: Dense blankets of fucoid seaweeds dominating sheltered, fully marine littoral rocky shores (F) and fucoids dominating variable salinity rocky shores (FVS).
No situation data available.
No temporal variation data available.
Characterising species data not applicable.
Not applicable or unknown.