There are 15 national nature reserves in the county. The largest is Bridgwater Bay which has been recognised under the Ramsar Convention and covers 2,639 hectares (6,521 acres) of mud flats, saltmarsh, sandflats and shingle ridges. The smallest is Hardington Moor at 8.7 hectares (21.5 acres) in area. Several of the sites are associated with rivers and low-lying areas of the Somerset Levels. The highest is Dunkery and Horner Wood which covers 1,604 hectares (3,964 acres) of wet and dry heathland, ancient woodland and open grassland on Exmoor including Dunkery Beacvon, the highest point in the county. Ebbor Gorge is important for both biological and geological interest.
This site comprises four meadows surrounded by well-established hedges on gently sloping clay-rich soils. It is an outstanding example of a traditionally managed unimproved neutral grassland of a type now rare in Britain. The meadows belong to a type characterised by the widespread occurrence of sweet vernal grass (Anthoxanthum odoratum), crested dog's-tail (Cynosurus cristatus), cowslip (Primula veris) and green-winged orchid (Orchis morio). A total of 74 species of orchids have so far been recorded. This site is one of only three localities in Britain in which the grass Gaudinia fragilis is a prominent feature of the sward.[3]
The Dunkery and Horner Wood NNR is one of the largest in England. It includes Dunkery Hill, the highest point on Exmoor and in Somerset, wet and dry heathland, ancient woodland and open grassland. Much of the NNR is within the National Trust-owned Holnicote Estate.[6]
The River Huntspill (or Huntspill River) is an artificial river, in the Somerset Levels. It was built in 1940 to supply process water to ROF Bridgwater, and has resulted in reduced flooding of the lower Brue Valley. Huntspill Sluice at the river's western end, also known as West Huntspill Sluice, separates it from the River Parrett. A stretch of the river, from Gold Corner to Huntspill Sluice (excluding the Cripps River), is a national nature reserve. The NNR is managed by the Environment Agency. The river discharges into the River Parrett, just south of Highbridge which then flows into Bridgwater Bay.[21] Public access to the site is restricted.
Rodney Stoke is a biological Site of Special Scientific Interest, just north of the village of Rodney Stoke in the Mendip Hills. Part of the site is a national nature reserve and part a Nature Conservation Review Woodland site. This site supports a mosaic of ancient semi-natural broadleaved woodland, scrub and species-rich unimproved grassland. Two nationally rare plants occur at Rodney Stoke: purple gromwell (Lithospermum purpurocaeruleum) and the endemic whitebeam (Sorbus anglica). The site supports a diverse fauna. Badgers (Meles meles) are common and two or three setts are occupied each year. Noctule bats (Nyctalus noctula) and pipistrelle bats (Pipistrellus pipistrellus) roost in Big Stoke. Breeding birds include buzzard (Buteo buteo) and spotted flycatcher (Muscicapa striata). Small enclosures and tall hedges provide sheltered conditions that are ideal for many species of invertebrate. Butterflies are well represented with marbled white (Melanargia galathea), purple hairstreak (Quercusia quercus), brown argus (Aricia agestis) and grayling (Hipparchia semele).[24] General access is only via the one footpath across the site.
The Somerset Levels national nature reserve covers several areas of the wider Somerset Levels. The specific sites include the Moorlinch SSSI, Southlake Moor and part of King's Sedgemoor. The habitats covered are open water and lowland grassland which are frequented by resident and visiting birds.[27] The water table is high for most of the year with frequent winter flooding from high ground and surface water remaining on many fields throughout the winter and early spring. Moorlinch contains a good proportion of botanically rich ditch systems.[28] Public access is restricted.
Owned by Exmoor National Park Authority, Tarr Steps Woodland national nature reserve covers 33 hectares of the River Barle valley. This is mainly sessile oak (Quercus petraea) woodland, with beech (Fagus), ash, sycamore (Acer pseudoplatanus), hazel (Corylus), blackberry (Rubus), bluebells (Hyacinthoides non-scripta) and honeysuckle (Lonicera).[29] It is internationally significant[30] for the mosses, liverworts and lichens which flourish in the cool damp conditions.[31][32] Much of the woodland was once coppiced, primarily to provide charcoal for the local iron smelting industry. The river and the valley woodlands are part of the Barle ValleySite of Special Scientific Interest and abound with wildlife, ranging from red deer to dormice, including the rare barbastelle bat (Barbastella barbastellus) and otter that feed along the unpolluted and fast-flowing river.[33]
^Unless specified otherwise, the area is taken from the MAGIC map of each site. (Click on the identify icon (i) in the "Feature Tools" and then click on the site.)
^The maps link to the UK Government MAGIC mapping system.
^Details are on the pages on each site in the Natural England listing of national nature reserves in the county.
References
^"Protected or designated areas". Department for Environment, Food & Rural Affairs and Natural England. Archived from the original on 4 May 2015. Retrieved 4 August 2015.
^"Bridgwater Bay NNR". National Nature Reserves. Natural England. Archived from the original on 10 January 2011. Retrieved 14 November 2010.
^"Dunkery and Horner Wood". Somerset's National Nature Reserves. Department for Environment, Food & Rural Affairs and Natural England. Archived from the original on 26 May 2015. Retrieved 5 August 2015.
^Bulleid, L.R.C.P., F.S.A., Arthur; Harold St. George Gray, M.A., F.S.A. (1948). The Meare Lake Village. Taunton: pub. privately. pp. 1–14. Archived from the original on 17 February 2012.{{cite book}}: CS1 maint: multiple names: authors list (link)
^"Westhay Moor". Taunton Local Group. Royal Society for the Protection of Birds. Archived from the original on 8 February 2015. Retrieved 8 February 2015.