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Habitats
Subtidal sands and gravels
Sand and gravel seabeds are widespread. Those found to the west of the UK include a high proportion of shell fragments, whereas those from the North Sea are mainly formed from rock. They occur in a range of environmental conditions, from wave-sheltered, enclosed bays and estuaries to highly exposed open coasts. The mix of sand or gravel, and any sand waves or ripples present on the surface of the seabed, depend on factors such as the strength of the waves and tides.
Subtidal sands and gravels © JNCC
The communities of animals that live in this habitat are also determined by the environmental conditions. There tend to be fewer animals where waves and tides are strong, and the communities there will be characterised by rapid burrowers such as bristleworms, tube worms, bivalve shells and shrimp-like creatures, and perhaps by crabs, hermit crabs and sea snails on the surface of the seabed.
Conversely, in quieter and deeper areas, sand and gravel seascapes can support some of the richest marine life communities. The variety of worms, sea snails and paired-shelled bivalves increases, to include, amongst others, great scallops and venus shells. Anemones, sea urchins, and sea cucumbers, as well as red seaweeds can also be found on sand and gravel seabeds.
Offshore gravel and sand habitats support internationally important commercial fisheries, such as those for scallops and flatfish.
Trawling and aggregate dredging present the greatest threats to sand and gravel communities, which can also be at risk from pollution, coastal development and oil exploration.
Brief description of European distribution
These habitats are widespread around the British Isles and in Europe.
Conservation status / need
UKBAP Priority Habitat
Listed in Annex 1 of the Habitats Directive as part of Sandbanks that are slightly covered by seawater all the time and Estuaries.
Further information sources
Priority habitat descriptions
(PDF 1.5Mb) (UKBAP)
Interesting fact
Offshore sand and gravel seascapes are important nursery grounds for the young of commercial fish species such as flatfish, bass, skates, and rays as well as sharks.
