Biodiversity & Conservation

Pioneer saltmarsh.



Image Steve Morris - LMU.Sm e.g. Salicornia sp. pioneer saltmarsh Image width ca 5 m in foreground.
Image copyright information

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Distribution map

LS.LMU.Sm recorded (dark blue bullet) and expected (light blue bullet) distribution in Britain and Ireland (see below)

  • EC_Habitats
  • UK_BAP

Marine natural heritage importance

Listed under EC Habitats Directive
UK Biodiversity Action Plan
National importance Not available
Habitat Directive feature (Annex 1) Estuaries

Biotope importance

Salt marshes are an important resource for wading birds and wildfowl. They act as high tide refuges for birds feeding on adjacent mudflats, as breeding sites for waders, gulls and terns and as a source of food for passerine birds particularly in autumn and winter. In winter, grazed salt marshes are used as feeding grounds by large flocks of wild ducks and geese (see ecological relationships). For example, Packham & Willis (1997) suggested that the UK coastline supported 1.5 -2 million waders during winter, which probably represented 50% of the European population. Packham & Liddle (1970) listed 250 species of birds that fed on the Cefni saltmarsh and adjacent tidal flats. Areas with high structural and plant diversity, particularly where freshwater seepage's provide a transition from fresh to brackish conditions, are particularly important for invertebrates. Salt marshes also provide sheltered nursery sites for several species of fish (Anon, 1999n).

Saltmarsh collects litter and detritus, from the resident population of plants and animals, and brought down rivers or in with the tides. The action of bacteria and invertebrates breaks down the detritus into particulate or dissolved organic nutrients. Saltmarsh habitats may be net exporters of nutrients to the wider community of estuaries or bays or net nutrient sinks depending on local conditions (Long & Mason, 1983; Adam, 1993). However, saltmarsh habitats are potentially important sources of organic carbon and productivity in some estuaries and bays.

The accumulation of sediment, and its consolidation by plants, results in a gradual seaward progression of the saltmarsh unless the marsh is eroded by storms or changes in the river channel. The low profile, raised bed and plant material attenuate wave action and water flow, reducing the impinging wave energy on the shore. Therefore, saltmarsh habitats, together with adjacent mudflats may form a natural, soft, coastal defense.


Saltmarsh areas may be used for grazing of sheep, cows or horses. Salicornia europaea (samphire) is collected for human consumption in some areas..

Additional information icon Additional information

As extensions of the intertidal flats saltmarsh habitats dissipate and absorb wave energy impacting on the shore and, therefore constitute part of a natural coastal and flood defence.

This review can be cited as follows:

Tyler-Walters, H. 2001. Pioneer saltmarsh.. Marine Life Information Network: Biology and Sensitivity Key Information Sub-programme [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 25/11/2015]. Available from: <>