Whitton Bridge Pasture

Geobox Protected Area
name = Whitton Bridge Pasture
native_name =
other_name =
other_name1 =
category_local = Site of Special Scientific Interest
category_iucn =


image_size =
image_caption =
country = England
region = North East
region_type = Region
district = Stockton-on-Tees
district_type = Unitary Authority
city =
city1 =
area_unit = ha
area = 3.18
area_round = 2
location = Whitton
lat_d = 54
lat_m = 35
lat_s = 38
lat_NS = N
long_d = 1
long_m = 24
long_s = 12
long_EW = W
elevation =
established_type = Notification
established = 2004
management_body = Natural England
management_location =
management_lat_d =
management_lat_m =
management_lat_s =
management_lat_NS =
management_long_d =
management_long_m =
management_long_s =
management_long_EW =
management_elevation =
visitation =
visitation_year =
free_type = Area of Search
free = Cleveland
free1_type = Interest
free1 = Biological

---

map_locator_x =
map_locator_y =
map_size = 243
map_caption =
map_locator = UK
map_first = yes
website = [http://www.natureonthemap.org.uk/map.aspx?
]

Whitton Bridge Pasture is a Site of Special Scientific Interest (SSSI) in the unitary authority of Stockton-on-Tees, England. At 3.18 hectares (7.9 acres) it lies to the south of Whitton village and north west of Stockton-on-Tees. SSSIs are chosen by Natural England with Whitton Bridge Pasture being designated in 2004 because of its biological interest. It is one of 18 SSSIs in the Cleveland area of search.

The biological interest is focussed on the species rich mesotrophic grassland, found across the site, which is actively maintained through grazing. The species present are predominantly grasses, while herbs and Orchids are also found. The area has been classified as MG5 under the British National Vegetation Classification due to the species composition. The site is small and isolated and therefore requires careful management to avoid damage from potentially threatening activity on neighbouring land.

Reason for notification

SSSIs are designated by Natural England, previously English Nature, which uses the 1974-1996 county system. This means there is no grouping of SSSIs by Stockton-on-Tees unitary authority, or County Durham which is the relevant ceremonial county. As such Whitton Bridge Pasture is one of 18 SSSIs in the Cleveland area of search. [cite web | title=SSSIs in Cleveland area of search | url=http://www.english-nature.org.uk/special/sssi/searchresults.cfm?sssi_name=&frmcounty=1007 | work=English Nature | accessdate=2007-01-31]

Whitton Bridge Pasture is nationally important for its species-rich grassland which is unimproved by fertilisers. This type of grassland—once common in the Tees lowland—is becoming increasingly rare with its associated species also becoming scarce. Whitton Bridge Pasture is one of only two remaining examples of this habitat in the Tees lowland area. The other example is Briarcroft Pasture an SSSI approximately 3 km to the south, which was designated at the same time but is significantly smaller.cite web | title=Briarcroft Pasture citation sheet| url=http://www.english-nature.org.uk/citation/citation_photo/2000475.pdf | work=English Nature | accessdate=2007-01-31]

Under the British National Vegetation Classification (NVC) Whitton Bridge Pasture is considered as mesotrophic grassland because it represents well-drained and permanent pasture. In particular it is considered the MG5 community due to the species present. MG5 is widespread in many lowland areas in England, Wales and Scotland, being particularly centred in the Midlands.cite book |editor=John S. Rodwell |title=British Plant Communities Volume 3: Grasslands and montane communities |pages=p. 63 |year=1998 |publisher=Cambridge University Press |location= |isbn= 0-521-62719-2 ] Whitton Bridge Pasture is predominantly subcommunity MG5c ("Danthonia decumbens"), however subcommunity MG5a ("Lathyrus pratensis") is present with a substantially different species composition.

ite description

Abiotic

Located north-west of the town Stockton-on-Tees and 500 meters south of the village of Whitton, it is a small site of 3.18 hectares (7.9 acres) lying between a sewage works and Whitton Beck. Topographically the site slopes north towards the stream from a height of 40 m to under 30 m. [cite web | title=Site map| url=http://www.natureonthemap.org.uk/map.aspx?
] The underlying geology of Whitton Bridge Pasture is responsible for shaping the species-rich community found on the surface. Glacial tills and sands are the prominent geological features resulting in a relatively base-poor soil, characteristic of glacial drift geology. The soils of MG5c ("Danthonia decumbens") subcommunity are typically acidic.

Because Whitton Bridge Pasture is located in North East England it experiences a climate that is different from the UK average. [cite web | title=East and North East England average climate| url=http://www.metoffice.gov.uk/climate/uk/averages/19712000/areal/england_e_&_ne.html | work=Met Office | accessdate=2007-02-24] The North East receives on average 370 mm less rainfall than the UK over a year. Similarly the North East has roughly 129 days each year with more than 1 mm of rainfall, this is over 25 days less than UK average. Despite these differences the temperature is similar for both the North East and the UK, although the North East does have fewer days with air frost and more hours of sunshine per year. [cite web | title=UK average climate| url=http://www.metoffice.gov.uk/climate/uk/averages/19712000/areal/uk.html | work=Met Office | accessdate=2007-02-24] [cite web | title=Durham average climate| url=http://www.metoffice.gov.uk/climate/uk/averages/19712000/sites/durham.html | work=Met Office | accessdate=2007-02-24]

Biotic

The majority of the site is made up of species-rich grassland (subcommunity MG5c), which comprises three dominant species of grass and several other grass species at lower abundances. The dominant species are Red Fescue ("Festuca rubra"), Common Bent ("Agrostis capillaris") and Yorkshire Fog ("Holcus lanatus"). The less abundant species of grass include, Crested Dog’s-tail ("Cynosurus cristatus"), Heath-grass ("Danthonia decumbens") and Cocksfoot ("Dactylis glomerata"). The subcommunity also has many broad-leaved herbs including Common Knapweed ("Centaurea nigra"), Tormentil ("Potentilla erecta"), Devils-bit scabious ("Succisa pratensis") and Betony ("Stachys officinalis").

A second subcommunity (MG5a) is present and is characterised by the legume Meadow vetchling ("Lathyrus pratensis"). Other species present in this subcommunity include Salad burnet ("Sanguisorba minor"), Quaking grass ("Briza media"), Pignut ("Conopodium majus") and the Orchid species: Common Twayblade ("Listera ovata") and Early Purple Orchid ("Orchis mascula"). The subcommunity also contains Meadow barley ("Hordeum secalinum"), a perennial grass, which is a characteristic species of the Tees Lowland.cite web | title=Whitton Bridge Pasture citation sheet| url=http://www.english-nature.org.uk/citation/citation_photo/2000474.pdf | work=English Nature | accessdate=2006-02-02]

The two subcommunities of MG5, characterised by species rich grassland form a belt across the site, however they do not cover the whole site. Towards the north there is a community dominated by False oat-grass ("Arrhenatherum elatius"). The False Oat-grass is a constant species in the MG1 and MG2 communities of the British NVC and is therefore not typical of an MG5 community. [cite book |editor=John S. Rodwell |title=British Plant Communities Volume 3: Grasslands and montane communities |pages=p. 514 |year=1998 |publisher=Cambridge University Press |location= |isbn= 0-521-62719-2 ] At Whitton Bridge Pasture it is growing on alluvial soils located at the northern edge of the site which have most likely been formed by Whitton Beck just north of the site. A number of springs at the site are associated with flushes of the Pale sedge ("Carex pallescens") which form small populations.

Management

Natural England's role is to advise and help the owners manage Whitton Bridge Pasture effectively. To achieve this Natural England provides guidelines for each SSSI. Species-rich grassland, such as that found at Whitton Bridge, requires careful management for it to retain its high species diversity. This means many activities are not allowed at the site including: ploughing, drainage and the use of fertilisers, pesticides or herbicides. [cite web | title=Prohibited actions | url=http://www.english-nature.org.uk/special/sssi/old/OLD2000474.pdf | work=English Nature | accessdate=2007-01-31] [cite web | title=Managing SSSIs | url=http://www.english-nature.org.uk/special/sssi/management.cfm | work=English Nature | accessdate=2007-02-20]

Management of the site does require moderate grazing during the summer and autumn to help maintain the species diversity. This is because grazing removes each year's new growth which helps stop the site becoming dominated by vigorously growing grasses. Such grasses would allow a build up of dead organic matter, which together with the increased growth, would reduce the growth of less vigorous species. The overall effect of this would be a reduction in species diversity, which was one of the reasons for the SSSI designation. Trampling can be of benefit because it breaks up accumulated dead organic matter.cite web | title=Views about management | url=http://www.english-nature.org.uk/special/sssi/sitedocuments.cfm?type=vam&sssi_id=2000474 | work=English Nature | format = Word document | accessdate=2007-01-31]

The small and isolated nature of the site makes it susceptible to damage from the surrounding area. For example herbicides, thought to be generally damaging for the species richness, could get onto the site from the drift of spray from surrounding fields. To help combat this the maintenance of mature hedgerows around the perimeter is encouraged. As of 2006 the condition of Whitton Bridge Pasture is described as favourable.cite web | title=Stockton-on-Tees Borough annual monitoring report 2005/2006 | url=http://www.egenda.stockton.gov.uk/aksstockton/images/att1131.doc | work=Stockton-on-Tees Borough council | format= Word document | accessdate=2007-02-03] This description means that the land is being adequately conserved and any conservation objectives are being met, however that there is scope for enhancement of the site. [cite web | title=SSSI glossary | url=http://www.english-nature.org.uk/special/sssi/glossary.cfm | work= English Nature | accessdate=2007-02-03] The condition of the site was also described as favourable in 2004 and 2005 assessments.cite web | title=Stockton-on-Tees Borough annual monitoring report 2004/2005 | url=http://www.stockton.gov.uk/resources/environment/planning/newsystem/amr_0405.pdf | work=Stockton-on-Tees Borough council | accessdate=2007-02-03] In the future it is hoped that the grazing regime will become more regularised and will be of high priority. [cite web | title=Condition of SSSI units | url=http://www.english-nature.org.uk/special/sssi/reportAction.cfm?report=sdrt13&category=S&reference=2000474 | work=English Nature | accessdate=2007-02-02]

References