Subtidal Sands and Gravels

Sublittoral sand and gravel habitats occur in a wide variety of environments, from sheltered to highly exposed conditions. Sand and gravel sediments are the most common habitats found below the level of the lowest tide around the coast of the UK. Whilst large areas of seabed are covered by sand and gravel, this may be in very thin deposits, and the strength of currents and exposure to wave action are important determinants of the topography and stability of these habitats, as well as the communities found.

Bass over subtidal sands and gravels

Photo: Gerald Legg

Why are they important?

  • In quieter and deeper areas, sand and gravel seascapes can support some of the richest marine life communities
  • Offshore gravel and sand habitats support internationally important fisheries
  • Sand and gravel habitats are important nursery areas for a number of fish species, including sharks and rays

Subtidal Sands and Gravels in Sussex

Subtidal sands and gravels are widespread in the region.

What are the threats?

  • Trawling for species such as scallops and flatfish, and aggregate dredging can damage sand and gravel habitats
  • Pollution and nutrients can result in anoxic conditions, which decrease species diversity
  • Oil exploration, leakages and shipping accidents lead to localised pollution of sediment organisms

Some associated species

  • Lesser Sand Eel Ammodytes tobianus
  • Painted Goby Pomatoschistus pictus
  • Bean-like Tellin Fabulina fibula
  • Green Sea Urchin Psammechinus miliaris

Great Scallop

Photo: Paul Naylor/Sussex Wildlife Trust

Links to more information

The Marine Life Information Network