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An Example of a European Site Designation Report
Severn Estuary (Wales) SAC, SPA and Ramsar site.
The mouth of the Severn Estuary (Wales) at grid reference ST321748, coordinates 511329N 030257W, is part of Great Britain’s longest river. The estuary is 14km between Cardiff (Lavernock Point) and Weston-Supar-Mare (Sand Point) with an intertidal habitat of 22,500ha (Kirby, 2005). It consists of four main rivers: Severn, Wye, Usk and Avon. Since the estuary is funnel shaped and has a predominant wind direction, its tidal range is the second highest in the world. Thus, according to JNCC (2006), it consists of “89% tidal rivers, estuaries, mud flats, sand flats, lagoons; 6% salt marshes, salt pastures, salt steppes; 4% coastal sand dunes, sand beaches, machair; 1% improved grassland”. The mouth of the Severn Estuary supports many populations of migratory waterfowl which are of international importance. In addition, it supports uncommon migratory fish (such as sea lampreys) and is a fish assemblage site, with over 100 species (Natural Habitats, 2009). Current land use: nature conservation, tourism, recreation, current scientific research, fishing-commercial, fishing-recreational/sport, gathering of shellfish, bait collection, grazing (unspecified).
JNCC (2007) states that the following acts: “1994 Habitats Regulations” and “the 2010 Habitat Regulations”, are being used to deliver holistic management of the uses of the estuary shown above. In Wales, Community Strategies and Local Biodiversity Action Plans contribute to achieve the aim of all-over conservation of all species, but particularly those named below.
Reasons for Designation and Nature Conservation Objectives
Special Protected Area
The Severn Estuary SPA is designated for its bird species, over winter and as an internationally important assemblage (JNCC).
Over winter the area regularly supports:
- Tundra Swan (Cygnus columbianus bewickii)- 3.9% of GB population (5 year peak mean 1991/92-1995/6).
- Gadwell (Anas strepera)- 0.9% of GB population (5 year peak mean 1991/92-1995/6);
- Greater White-Fronted Goose (Anser albifrons albifrons)-0.4% of GB population (5 year peak mean 1991/92-1995/6);
- Dunlin (Calidris alpina alpina)- 3.3% of GB population (5 year peak mean 1991/92-1995/6);
- Shelduck (Tadorna tadorna)- 1.1% of GB population (5 year peak mean 1991/92-1995/6);
- Redshank (Tringa totanus)-1.3% of GB population (5 year peak mean 1991/92-1995/6).
The site qualifies as an internationally important assemblage of birds as it regularly supports 84317 waterfowl (Severn Estuary Partnership, 2012).
Special Area of Conservation
The Severn Estuary is an SAC because of regularly occurring migratory birds and fishes (JNCC).
Regularly occurring migratory birds:
- Twait Shad (Alosa fallax)-Resident-Common. Population A, Conservation B, Isolation C, Global A.
- Allis Shad (Alosa alosa): Resident-Very Rare. Population D;
- European River Lamprey (Lampetra fluviatilis): Resident-Common. Population C, Conservation B, Isolation C, Global B;
- Sea Lamprey (Petromyzon marinus): Resident-Common. Population C, Conservation A, Isolation C, Global B.
Convention of Wetlands of International Importance
The Severn Estuary is a Ramsar site because (JNCC):
- Criterion 1- it has the second largest tidal range in the world. The habitats present on the pSAC include: covered sandbanks, estuaries, mudflats and exposed sandflats, Atlantic salt meadows.
- Criterion 3- there are unusual communities, low diversity and high productivity.
- Criterion 4- important for migratory fish, including Salmon (Salmo salar), Sea Trout (S. trutta), Sea Lamprey (Petromyzon marinus), River Lamprey (Lampetra fluviatilis). It is also important for migratory birds in the spring and autumn.
- Criterion 5- 70919 waterfowl (5 year peak mean 1998/99-2002/03).
- Criterion 6- species and populations of international importance: Tundra Swan (Cygnus columbianus bewickii), Greater White-Fronted Goose (Anser albifrons albifrons), Gadwell (Anas strepera) and Dunlin (Calidris alpina alpina).
- Criterion 8- over 110 species of recorded fish so is one of the most diverse in Britain. It is used for migration, food, as a spawning grounds and a nursery.
The current pressures upon the Seven Estuary are:
- On and off site recreation and tourism disturbance (unspecified).
- On and off site dredging.
- On-site erosion.
All three adverse factors are in reporting category one, so still occur, but it is not clear if they are being properly managed and regulated.
JNCC 2008. Information Sheet on Ramsar Wetlands (RIS) UK11081 (version 3.0) [online]. (Updated 13th June 2008). Available from http://www.jncc.gov.uk/pdf/RIS/UK11081 (cited 19th October 2012).
JNCC 2007. Seven Estuary, Standard Natura 2000 Data Form UK0013030 (version 1.0) [online]. (Updated 07th September 2011). Available from http://www.jncc.gov.uk/pdf/RIS/UK0013030 (cited 19th October 2012).
JNCC 1999. Seven Estuary, Standard Natura 2000 Data Form UK9015022 (version 1.0) [online]. (Updated 05th May 2006). Available from http://www.jncc.gov.uk/pdf/RIS/ UK9015022
(cited 19th October 2012).
Kirby 2005. Distribution, transport and exchanges of fine sediment, with tidal power implications: Severn Estuary, UK [online]. Elsvier. Science Direct. Available from www.elsevier.com/locate/marpolbul (cited 19th October 2012).
Natural Habitats 2009. The Severn Estuary. Natural England and the Countryside Council for Wales’ Advice [online]. Available from http://www.naturalengland.org.uk/ourwork/marine/mpa/severnestuaryreg33.aspx (cited 19th October 2012).
Severn Estuary Partnership 2012. The Severn Estuary Coastal Habitat Management Plan [online]. Available from www.severnestuary.net/secg/docs/executive_summary.pdf (cited 19th October 2012).