River Avon

Site details

UK map showing location of River Avon Special Area of Conservation/Site of Community Importance.
Location of River Avon SAC/SCI/cSAC


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

3260 Water courses of plain to montane levels with the Ranunculion fluitantis and Callitricho-Batrachion vegetation
The Avon in southern England is a large, lowland river system that includes sections running through chalk and clay, with transitions between the two. Five aquatic Ranunculus species occur in the river system, but stream water-crowfoot Ranunculus penicillatus ssp. pseudofluitans and river water-crowfoot R. fluitans are the main dominants. Some winterbourne reaches, where R. peltatus is the dominant water-crowfoot species, are included in the SAC.

Annex I habitats present as a qualifying feature, but not a primary reason for selection of this site

Not applicable.

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

1016 Desmoulin`s whorl snail  Vertigo moulinsiana
There is an extensive population of Desmoulinís whorl snail Vertigo moulinsiana along about 20†km of the margins and associated wetlands of the Rivers Avon, Bourne and Wylye. This is one of two sites representing the species in the south-western part of its range, in chalk stream habitat. It occurs here in a separate catchment from the Kennet and Lambourn, within an environment more heavily dominated by arable agriculture.
1095 Sea lamprey  Petromyzon marinus
The Avon represents sea lamprey Petromyzon marinus in a high-quality river in the southern part of its range. There are excellent examples of the features that the species needs for survival, including extensive areas of sand and gravel in the middle to lower reaches of the river where sea lampreys are known to spawn.
1096 Brook lamprey  Lampetra planeri
The Avon is a high-quality river that represents the southern part of the range of brook lamprey Lampetra planeri. A healthy, stable population occurs in the main river and in a number of tributaries. The main river, and in particular its tributaries, provides clean beds of gravel for spawning and extensive areas of fine silt for juveniles to burrow into.
1106 Atlantic salmon  Salmo salar
The Avon in southern England represents a south coast chalk river supporting Atlantic salmon Salmo salar. The salmon populations here are typical of a high-quality chalk stream, unaffected by the introduction of genetic stock of non-native origin. The Avon has an excellent mosaic of aquatic habitats, which include extensive areas of gravels essential for spawning and growth of juvenile fry. There has been limited modification of the river course by comparison with many other southern lowland rivers in England.
1163 Bullhead  Cottus gobio
The Avon represents bullhead Cottus gobio in a calcareous, relatively unmodified river in the southern part of its range in England. The River Avon has a mosaic of aquatic habitats that support a diverse fish community. The bullhead is an important component of this community, particularly in the tributaries.

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

Not applicable.

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