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Special Areas of Conservation

Dee Estuary/ Aber Dyfrdwy

Designated Special Area of Conservation (SAC)
Country England/Wales
Unitary Authority Cheshire, East Wales, Extra-Regio, Merseyside, West Wales and The Valleys
Centroid* SJ191819
Latitude 53.32833333
Longitude -3.216111111
SAC EU Code UK0030131
Status Designated Special Area of Conservation (SAC)
Area (ha) 15805.27
* This is the approximate central point of the SAC. In the case of large, linear or composite sites, this may not represent the location where a feature occurs within the SAC.
Location of Dee Estuary/ Aber Dyfrdwy SAC

General site character

  • Tidal rivers, Estuaries, Mud flats, Sand flats, Lagoons (including saltwork basins) (81.8%)
  • Salt marshes, Salt pastures, Salt steppes (16.1%)
  • Coastal sand dunes, Sand beaches, Machair (0.7%)
  • Shingle, Sea cliffs, Islets (0.5%)
  • Bogs, Marshes, Water fringed vegetation, Fens (0.4%)
  • Humid grassland, Mesophile grassland (0.2%)
  • Improved grassland (0.1%)
  • Broad-leaved deciduous woodland (0.1%)
  • Other land (including Towns, Villages, Roads, Waste places, Mines, Industrial sites) (0.1%)

Download the Natura 2000 standard data form for this site as submitted to Europe (PDF <100kb)

Note When undertaking an appropriate assessment of impacts at a site, all features of European importance (both primary and non-primary) need to be considered.

Annex I habitats that are a primary reason for selection of this site

  • Species occurrence description not yet available.

  • The Dee Estuary is representative of pioneer glasswort Salicornia spp. saltmarsh in the north-west of the UK. Salicornia spp. saltmarsh forms extensive stands in the Dee, especially on the more sandy muds where there is reduced tidal scour. It mainly occurs on the seaward fringes as a pioneer community, and moving landwards usually forms a transition to common saltmarsh-grass Puccinellia maritima saltmarsh (SM10). There is also a low frequency of Salicornia spp. extending well inland. Associated species often include annual sea-blite Suaeda maritima and hybrid scurvy grass Cochlearia x hollandica.

  • The Dee Estuary is representative of H1330 Atlantic salt meadows in the north-west of the UK. It forms the most extensive type of saltmarsh in the Dee, and since the 1980s it has probably displaced very large quantities of the non-native common cord-grass Spartina anglica. The high accretion rates found in the estuary are likely to favour further development of this type of vegetation. The saltmarsh is regularly inundated by the sea; characteristic salt-tolerant perennial flowering plant species include common saltmarsh-grass Puccinellia maritima, sea aster Aster tripolium, and sea arrowgrass Triglochin maritima. In a few areas there are unusual transitions to wet woodland habitats.

Annex II species that are a primary reason for selection of this site

  • Not Applicable

Annex II species present as a qualifying feature, but not a primary reason for site selection

Many designated sites are on private land: the listing of a site in these pages does not imply any right of public access.