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Special Areas of Conservation

River Wye/ Afon Gwy

Designated Special Area of Conservation (SAC)
Country England/Wales
Unitary Authority East Wales, Gloucestershire, Wiltshire and Bristol/Bath area, Herefordshire, Worcestershire and Warwickshire, West Wales and The Valleys
Centroid* SO109369
Latitude 52.02333333
Longitude -3.299722222
SAC EU Code UK0012642
Status Designated Special Area of Conservation (SAC)
Area (ha) 2147.64
* 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 River Wye/ Afon Gwy SAC

General site character

  • Tidal rivers, Estuaries, Mud flats, Sand flats, Lagoons (including saltwork basins) (9.5%)
  • Salt marshes, Salt pastures, Salt steppes (1.5%)
  • Inland water bodies (Standing water, Running water) (52.5%)
  • Bogs, Marshes, Water fringed vegetation, Fens (3.1%)
  • Heath, Scrub, Maquis and Garrigue, Phygrana (1%)
  • Dry grassland, Steppes (5.3%)
  • Humid grassland, Mesophile grassland (2.4%)
  • Improved grassland (10.4%)
  • Broad-leaved deciduous woodland (12.3%)
  • Inland rocks, Screes, Sands, Permanent Snow and ice (0.2%)
  • Other land (including Towns, Villages, Roads, Waste places, Mines, Industrial sites) (1.8%)

Download the Standard Data Form for this site (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

  • The Wye, on the border of England and Wales, is a large river representative of sub-type 2. It has a geologically mixed catchment, including shales and sandstones, and there is a clear transition between the upland reaches, with characteristic bryophyte-dominated vegetation, and the lower reaches, with extensive Ranunculus beds. There is a varied water-crowfoot Ranunculus flora; stream water-crowfoot R. penicillatus ssp. pseudofluitans is abundant, with other Ranunculus species – including the uncommon river water-crowfoot R. fluitans – found locally. Other species characteristic of sub-type 2 include flowering-rush Butomus umbellatus, lesser water-parsnip Berula erecta and curled pondweed Potamogeton crispus. There is an exceptional range of aquatic flora in the catchment including river jelly-lichen Collema dichotum. The river channel is largely unmodified and includes some excellent gorges, as well as significant areas of associated woodland.

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

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

  • 1092 White-clawed (or Atlantic stream) crayfish Austropotamobius pallipes

    The Welsh River Wye system is the best site known in Wales for white-clawed crayfish Austropotamobius pallipes. The tributaries are the main haven for the species, particularly at the confluences of the main river and the Edw, Dulas Brook, Sgithwen and Clettwr Brook.

  • 1095 Sea lamprey Petromyzon marinus

    The Wye is an extensive river system crossing the border between England and Wales and the sea lamprey Petromyzon marinus population is found in the main stem below Llyswen. The site provides exceptionally good quality habitat for sea lamprey and supports a healthy population.

  • 1096 Brook lamprey Lampetra planeri

    The Wye is an extensive river system spanning the border between England and Wales and the brook lamprey Lampetra planeri population is widely distributed in its catchment. The river provides exceptionally good quality habitat for brook lamprey and supports a healthy population.

  • 1099 River lamprey Lampetra fluviatilis

    The Wye is an extensive river system crossing the border between England and Wales, and the river lamprey Lampetra fluviatilis population is widely distributed in the catchment. The Wye provides exceptionally good quality habitat for river lamprey and supports a healthy population.

  • 1103 Twaite shad Alosa fallax

    Twaite shad Alosa fallax have long been abundant in the Wye, an extensive river system spanning the border between England and Wales. Twaite shad often spawn at or just above the tidal limit, but in the Wye they migrate over 100 km upstream, the highest spawning site being at Builth Wells. Data held by the Environment Agency indicate that, of the three selected rivers, the largest spawning areas for this species occur on the Wye. The river has relatively good water quality, adequate flows through an unobstructed main channel and a wide range of aquatic habitats conducive to supporting this fish species. In particular, there are a number of deep pools essential for congregation before spawning.

  • 1106 Atlantic salmon Salmo salar

    Historically, the Wye is the most famous and productive river in Wales for Atlantic salmon Salmo salar, with high-quality spawning grounds and juvenile habitat in both the main channel and tributaries; water quality in the system is generally favourable. It is also one of the most diverse river systems in the UK, with a transition from hard geology, high gradients, rapid flow fluctuations and low nutrient-content in its upper reaches, to a more nutrient-rich river with lower gradient, more stable flow and softer geology in the lowlands. The effect of river engineering work on migration and spawning has been limited, although there is a localised influence from the Elan Valley reservoirs, through inundation of spawning and nursery habitat and fluctuations in flow and water levels in the upper Wye. The most important tributaries for spawning are included in the SAC. Although in the past non-native salmon may have been released to the system, the impact of this is likely to have been minimal. The Wye salmon population is particularly notable for the very high proportion (around 75%) of multi sea winter (MSW) fish, a stock component which has declined sharply in recent years throughout the UK. This pattern has also occurred in the Wye, with a consequent marked decline in the population since the 1980s. However, the Wye salmon population is still of considerable importance in UK terms.

  • 1163 Bullhead Cottus gobio

    The Wye represents bullhead Cottus gobio in an extensive river system crossing the border between England and Wales. The Wye is one of the most diverse river systems in the UK, with a range of nutrient conditions and aquatic habitats and generally good water quality for fish species. The diversity of habitat types in the Wye means that it is likely to represent most of the habitat conditions in which bullhead occurs in Britain, highlighting the conservation importance of this river.

  • 1355 Otter Lutra lutra

    The Wye holds the densest and most well-established otter Lutra lutra population in Wales, representative of otters occurring in lowland freshwater habitats in the borders of Wales. The river has bank-side vegetation cover, abundant food supply, clean water and undisturbed areas of dense scrub suitable for breeding, making it particularly favourable as otter habitat. The population remained even during the lowest point of the UK decline, confirming that the site is particularly favourable for this species and the population likely to be highly stable.

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.