July 1999 Berkshire Lowland Unimproved Grassland BAP 1999-2005 BERKSHIRE LOWLAND UNIMPROVED GRASSLAND BIODIVERSITY ACTION PLAN Produced by English Nature on behalf of the Berkshire Nature Conservation Forum Coordinator - Sarah Davies Compiler - Jo Lewis Contributors - Sarah Davies, Graham Steven, Wanda Fojt This plan covers the three main types of Lowland Grassland habitat found in Berkshire - calcareous , neutral (MG5) and acid grasslands. These botanically rich grasslands have escaped agricultural improvement or development and now represent an important and scarce resource which was once much more widespread. Unimproved grasslands are rich, diverse habitats supporting a wide range of plants and animals. They have very high conservation value in terms of contribution to overall biodiversity but also have significant aesthetic, historic and recreational value. Wet neutral grasslands of high botanical interest (eg MG4, MG8, MG11, MG 13) and/or of high interest for breeding birds (MG10) are not covered by this action plan but can be found in the River Valley Habitats Action Plan. Similarly, acid grassland where it occurs as a mosaic with heathland is covered by the Heathland Action Plan. 1 CURRENT STATUS SSSIs are designated under the Wildlife and Countryside Act 1981 with the aim of identifying and protecting sites which 1.1 In Europe represent the best examples of all the natural habitats found in this country. Dry semi-natural lowland grasslands, which were once widespread in Europe, are now a In compliance with the Convention on scarce and threatened habitat. There are no Biological Diversity (1992 Earth Summit) the overall estimates available for extent of this UK Biodiversity Action Plan (UKBAP) lays out type of habitat in Europe as a whole but losses national strategies for the protection and to development and agricultural intensification sustainable use of Biodiversity. Threatened are known to be substantial. habitats and species in need of individual BAPs have been identified, including a 1.2 Statutory recognition number of grassland communities and species dependent on such habitats. The EC Habitats Directive aims to establish, by the year 2000, a network of protected 1.3 In the United Kingdom and areas designed to maintain the distribution England and abundance of threatened species and habitats. This network, Natura 2000, will comprise Special Areas for Conservation Lowland unimproved grasslands of high (SACs) designated for the protection of certain botanical interest constitute approximately 3% threatened habitats and the habitats of listed of all permanent grassland in the English species, along with Special Protection Areas Lowlands. An estimated 97% of unimproved (SPAs) designated under the Birds Directive. grasslands were lost in England and Wales Chalk grasslands and lowland hay meadows between 1930 and 1984. Losses have been are listed in Annex I of the Habitats Directive estimated at 2-10% per year in some areas as natural habitat types of Community interest across the country during the 1980s and whose conservation requires the designation 1990s. In area terms it is likely that less than of SACs. Calcareous grasslands supporting 100,000 hectares of lowland unimproved important orchid sites or juniper populations grasslands remain in England. are also listed in Annex I. In the UK, internationally important chalk Around 80% of these grasslands have been grasslands , as defined under the Habitats destroyed since 1940. A survey of chalk Directive, occupy less than 50,000 ha. grassland SSSIs found that 44% of the 1 July 1999 Berkshire Lowland Unimproved Grassland BAP 1999-2005 management units were in less than ideal grassland sites are usually very small in size. condition, with 19% still in a declining condition demonstrating both the vulnerability Acid grassland in Berkshire is uncommon of this habitat and lack of appropriate with only 3 sites recorded in the Berkshire management. Grassland Inventory. Greenham Common and With between 5,000 and 10,000 ha. of neutral Windsor Great Park are the most important grasslands remaining nationally, even sites for this resource although small stronghold areas have only small, usually fragments are present within heathland fragmented patches. A sample of eight mosaics elsewhere. counties produced a mean site size of 7.1 ha. for MG5 grassland, a grassland community Figure 1 shows the proportion of nationally virtually endemic to the UK. important NVC lowland unimproved grassland Lowland acid grassland is becoming increasingly rare. Survey data on the extent and conservation status of acid grasslands in this country is limited but best estimates state that there are less than 30,000 ha. remaining. A random sample of 47 SSSIs showed that 66% of the sites contained less than 10 ha of acid grassland and 83% had less than 20 ha, demonstrating the fragmented nature of the resource in this country. Habitat type Extent in England (including NVC) Calcareous/chalk Less than 50,000 ha grasslands ( CG1-CG9) in total communities present within Berkshire. 1.6 In the London Basin, Berkshire Neutral grasslands Between 5,000 and (MG5) 10,000 ha in total and Marlborough Downs and Chilterns Natural Areas Lowland acid Less than 30,000 ha grasslands (U1-U4) in total Berkshire os chalk grassland resource is Table 1. Extent of the three main lowland mainly restricted to the Berkshire and semi-natural grassland types in England. Marlborough Downs Natural Area. This Natural Area supports around 5% (25,000 ha.) 1.4 In Berkshire of the remaining chalk downland resource in England and is therefore recognised by Berkshire currently supports seven nationally English Nature as a key habitat type. rare lowland unimproved grassland habitats Additional small areas of Berkshire os chalk which include neutral, calcareous and acid grassland occur within the Chilterns and the grassland types. Berkshire supports 174 ha. North Hampshire Downs Natural Areas. of chalk grassland, 115 ha. of neutral grassland (see Figure 1) and an estimated Neutral grassland in Berkshire is almost 150 ha. of acid grassland. exclusively restricted to the alluvial flood plains of the River Thames and its tributaries within Berkshire os chalk grassland has been the London Basin Natural Area, the exception reduced from around 500 ha. in 1960 to being a concentration of sites in the 174.72 ha. today. A survey of 29 Berkshire Bucklebury area. chalk grassland sites in 1985 found that 79% were less than 10 ha in size and no sites Acid grassland covers only a very small area surveyed were greater than 40 ha. within the County but can often be found in association with heathland and on a variety of A survey of the County os neutral grassland different substrates including the Reading in 1995 suggested that around 50% of the Beds in the London Basin Natural Area. resource has been damaged or destroyed since the previous survey in 1984. Neutral 2 July 1999 Berkshire Lowland Unimproved Grassland BAP 1999-2005 1.7 In the Unitary Authorities 1.8 Associated BAP species West Berkshire District supports the entire chalk grassland interest of Berkshire with the Lowland grassland in England supports a rich exception of Cock Marsh SSSI in the Royal variety of wild plants and animals. Among England os rare and scarce species of plants, birds and butterflies, 25%, 20% and 65% respectively are closely associated with lowland grassland. This high biodiversity is the result of England os varied topography, geology, soils, climate and past land use. Priority BAP species which the Berkshire grasslands are known to support are shown in Table 2. Mammals: Birds: Borough of Windsor and Maidenhead. Brown hare Skylark The Royal Borough of Windsor and Stone Curlew Maidenhead (38%), West Berkshire (34%) Plants: Cirl bunting and Wokingham (21%) contain the largest Deptford Pink Grey partridge areas of neutral grassland in Berkshire. Pennyroyal Corn bunting Bracknell Forest Borough contains the Whorled Caraway Woodlark remaining 7% of neutral grassland in Berkshire. Invertebrates: Silver spotted skipper Acid grassland in Berkshire is uncommon Adonis blue with only 3 sites recorded in the Berkshire Marsh fritillary Grassland Inventory. Greenham Common in Light feathered rustic moth West Berkshire and Windsor Forest and Bordered gothic moth Great Park in the Royal Borough of Windsor Narrow bordered bee hawk moth and Maidenhead are the most important sites Pale shining brown hawk moth for this resource although small fragments are The four-spotted moth present within heathland mosaics elsewhere. Andrena lepida (a mining bee) Great yellow bumble bee Figures 2 and 3 show the proportion of neutral Brown banded mini bee lowland and calcareous unimproved grassland Large garden bumble bee respectively within each Unitary Authority Shrill carder bee Area. Dorycera graminium (a large otitid) Harpalus dimidiatus (a ground beetle) Chalk grasslands have been identified as the habitat type that supports the fourth highest number of species of conservation concern in this country. Grassland habitats support over 150 Red Data Book invertebrate species. Other notable species supported by unimproved grasslands include the chalkhill blue butterfly, wheatear and meadow pipit which are all identified in the UK BAP long list. Plant species known to have been present in 3 July 1999 Berkshire Lowland Unimproved Grassland BAP 1999-2005 grassland sites in Berkshire that have now chamomile and whorled caraway. disappeared include the pasque flower, 2. CURRENT ISSUES the practicalities of stock rearing are often limiting. On some sites the nature of the AFFECTING THE HABITAT tenure over a piece of land can make it difficult to implement appropriate The main issues affecting unimproved, management, such as common land where lowland grasslands are much the same in fencing is not permitted without permission Berkshire as they are across Europe, resulting from the Secretary of State for the in reduced quality and quantity of the habitat. Environment. Pollution through aerial deposition of chemicals and climate change Agricultural improvement should also be considered although they are Ploughing, reseeding, drainage, conversion to factors which are not yet fully assessed.