Low energy infralittoral rock

Shallow water rock, below the tides, sheltered from waves and currents

Shallow water rock, below the tides, sheltered from waves and currents © Lin Baldock

 

The weak waves and currents typical of sheltered rocky seascapes allow silt to build up on the seabed, and the water can be somewhat murky.

The seaweeds that live in these areas may be exposed to the air on extremely low tides.  They are also adapted to the fine silt particles and the lower water clarity. Varieties include sugar kelp as well as delicate red seaweeds.  Crusts of coralline algae, which look nothing like a typical seaweed are also found in these sheltered rocky areas.

The animal community is dominated by those that graze on the seaweeds, including edible sea urchins and common brittlestars.  Sea squirts are also found on the rocks, and where the water is really murky, such as in estuaries, seaweeds may be replaced by beds of mussels and barnacles.

For the official habitat definition please see the documents listed below.

 

European distribution

This habitat is found mainly in estuaries, sheltered bays and inlets in the south-west of England and in Scottish lochs.

Shallow water rock, below the tides, sheltered from waves and currents fact

 

Official habitat definition

EUNIS habitat A3.3 Atlantic and Mediterranean low energy infralittoral rock

 

Further information

JNCC Marine Habitat Classification

JNCC EUNIS habitat correlations table