Buckinghamshire and Milton Keynes Habitat

Buckinghamshire & Milton Keynes Habitat Mapping Project Foreword Contents Executive Summary

The landscape and habitats of Buckinghamshire and grain environmental assessment which is held Executive Summary 3 Buckinghamshire and Milton Keynes contain a variety It is now possible to present accurate and up to date Milton Keynes have long been recognised for their together in one single database. The database holds of habitats, from the rolling hills of the Chilterns, with information on the extent of habitats across the richness and variety. From ancient parklands in specific information of well over 65,000 land parcels Part 1: Overview of the study 4 their chalk grassland and beech woodlands, to the county. These can be utilised in a variety of situations South Bucks, Chilterns chalk grasslands, to the wet across the entirety of Buckinghamshire and Milton Background 4 Vale of Aylesbury with its ancient parklands and wet including; strategic and green infrastructure planning, meadows associated with Aylesbury Vale and Milton Keynes and classifies each of these in accordance to Methodology 6 meadows, into Milton Keynes' rich interlinked city and local biodiversity action planning, land use and climate Keynes, our natural environment provides an 191 different landuse and habitat categories. Used on Habitats in Buckinghamshire and Milton Keynes 7 parkland landscape. Until now the distribution of change monitoring along with development of important contribution to the quality of our area, its own, or brought together with other related these habitats has not been fully understood. ecological networks. The data can also function as an making it a prime location to live, work and invest. environmental information, the data allows detailed Part 2: Results Habitats 8 However, the Habitat Mapping Project, set up by information source for local communities and will interrogation and assessment of habitats and landuse. Buckinghamshire County Council, Buckinghamshire & assist in the identification of local priorities for nature Lowland Calcareous Grassland 8 The environment is being placed under increasing As such the data is of value to a wide range of Milton Keynes Environmental Record Centre and conservation as well as present background Lowland Dry Acid Grassland 10 pressure from changes brought about by climate, professionals including developers, engineers, Milton Keynes Council, has now changed this. For the information to inform local community green Lowland Beech and Yew Woodland 12 growth and development. Strategy and policy is strategic planners, transport officers, land and first time this mapping project brings together all infrastructure plans. Lowland Meadow 14 changing to address such issues and are meant to environment managers and ecologists. It enables available information on habitats within Lowland Fen 16 better safeguard landscape qualities. Section 40 of the informed decision-making about development Buckinghamshire and Milton Keynes creating an Lowland Wood-pasture and Parkland 18 Natural Environment and Rural Communities Act proposals, land use and land management change as important resource for a wide variety of applications. Lowland Heathland 20 2006 provides just one example. It places a duty on well as ensuring the protection of the natural all public authorities to have due regard for resources. It allows for the establishment of priorities, Using the Integrated Habitat System all undeveloped Part 3: Results Districts 22 conserving biodiversity. Underpinning this the identification of opportunities and will be an land in the county has been digitally mapped. The Aylesbury Vale District 22 requirement is the need for authorities to ensure important mitigation tool. project brings together both new and existing Chiltern District 24 they are equipped with a good understanding of their information on a range of habitats making it Milton Keynes 26 natural environments. We urge all involved in the planning, conservation and accessible through a Geographical Information System South Bucks District 28 promotion of our beautiful environment to consider (GIS). This report provides an overview of the Wycombe District 30 The Buckinghamshire and Milton Keynes Habitat this resource and to employ it as a means to secure a habitats occurring in the county, their distribution and Bringing this information together Mapping Project provides, for the first time, a fine sustainable environment for all. underlying characteristics. Data is pooled into five Part 4: Using Bucks and MK Habitat administrative areas presenting a summary of the enhances understanding of our natural Mapping 32 habitat resource for each district. This represents a heritage, and as we move forward this Applications 32 major step forward in our understanding, and creates resource will strengthen efforts to Further Information 32 an important tool to conserve the natural develop innovative, more expansive Technical Appendices 33 environment at a time when it is experiencing approaches to wildlife conservation. increased pressures.

Martin Tett Mike Galloway Please note for the purpose of this document the word ‘county’ refers to the administrative boundaries of Buckinghamshire and Cabinet Member for Cabinet Member for Milton Keynes. Planning & Environment Development Control & Environment Buckinghamshire County Council Milton Keynes Council Page 2 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 3 Foreword Contents Executive Summary

Study area The absence of a landscape-scale habitat dataset In order to address these issues the Natural The Integrated Habitat System has been developed by Hierarchy with habitat parcels represented a gap in the knowledge of the natural Environment Team at Buckinghamshire County Somerset Environmental Records Centre in environment resource. Although much information Council in partnership with Buckinghamshire & consultation with other organisations over the last Annex 1 Habitat already exists on habitats, the adoption of a Milton Keynes Environmental Records Centre began ten years. In Somerset, it has been in operational use Priority Habitat Type Inverse of Annex 1 Habitat standardised approach to the collection, management a habitat mapping project using the Integrated Habitat since 1999 and elsewhere around the UK since 2000. and provision of habitat data was required. This System designed by the Somerset Environmental The system was devised to rationalise the many Broad Habitat Type Inverse of Priority Habitat presented three key issues that needed to be addressed: Records Centre. habitat mapping methods currently in use and is Other Habitat increasingly recognised as the means by which habitat Data is held in a variety of formats. The mapping exercise was based on rapid assessment data is collated and managed. Natural England Survey activity during the last 20 years has generated of land cover from aerial photographs, supplemented supports the development of a regional and ultimately Example of IHS structure habitat data which is held in various formats and in with documentary evidence including survey reports, national habitat dataset, into which the different ways (GIS, survey reports, Phase 1 habitat site citations, and where feasible some 'ground- Buckinghamshire and Milton Keynes data will feed. Lowland Calcareous Grassland Semi-Natural Dry Grassland and maps). truthing' to ensure consistency and accuracy. The (Priority Habitat) Scrubland Facies on Calcareous method allows a hierarchical assessment of habitats The classification comprises over 400 habitat Calcareous Grassland Substrates (Annex1) Substantial gaps in data coverage. and their importance to be mapped, taking into categories, the majority drawn from existing Upland Calcareous Grassland Designated sites represent the majority of areas for consideration the EU Habitats Directive Annex 1 classifications, together with descriptions arranged in (Priority Habitat) which we hold detailed ecological information. A Habitats, UK Biodiversity Action Plan Priority a logical hierarchy. The hierarchical system allows total of 19,391ha of land is designated for nature Habitats, as well as the Phase 1 Habitat Survey classification to be applied reflecting the quality of the Information contained within data: conservation purpose, leaving 179,065 ha of land for method devised by the Joint Nature Conservancy information available. Habitat code: Identifies the basic habitat such as Broadleaved Woodland or Improved Grassland. One habitat which such information is absent. Council. code is allowed for each polygon. In order to present additional information available Accessibility and availability of data to users. It is envisaged that the habitat map will be maintained for a land parcel, the IHS uses a range of codes which Matrix code: Records secondary habitat components such as scrub, scattered trees or bracken. Two matrix Survey information is often contained within reports and updated on an annual basis with new data being allows identification of management type, habitat codes are allowed for each polygon. that have a limited distribution and is therefore not added as it becomes available. matrix and origin of habitat. widely available to users who would benefit from Formation code: Expresses information in relation to the formation of a particulate habitat type. In relation to access to it. woodland this code describes formation (plantation or semi-natural origin) and species mix (native or non- Designated sites in Buckinghamshire and Milton Keynes active). Two formation codes are allowed for each polygon. Special Area of Conservation (SAC) Local Wildlife Site (LWS) Statutory site of European importance for wildlife. Non-statutory site regarded to be of local importance for wildlife. Management code: Classifies the management or land use of a habitat parcel, such as coppice, wood-pasture and parkland, grazing and amenity grassland. Two management codes are allowed for each polygon. Site of Special Scientific Interest (SSSI) Biological Notification Site (BNS) Statutory site notified for being of national nature A term used in the past for wildlife sites of county importance in or geological conservation importance. Bucks and MK notified in the late eighties and early nineties.

Page 4 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 5 Part 1: Overview - Background Overview The Integrated Habitat System (IHS)

Page 4 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 5 Overview Methodology Overview Buckinghamshire and Milton Keynes Habitat Types

The habitat map is based on Ordnance Survey Steps in the assignment of IHS codes Buckinghamshire and Milton Keynes support a wide Habitats present in Buckinghamshire and Milton Keynes MasterMap polygons. These were assigned individual variety of habitat and landscape types. The majority of A selection of priority habitats are described on the following pages and highlighted in bold below IHS codes in a purpose built database depending the county's rural area is made up of grassland and upon the underlying habitat type. Variation in habitat, agricultural land, but large areas of woodland also Rivers and streams Lowland wood-pasture and parkland management, matrix or formation resulted in a exist. Acid grassland, dwarf scrub, heath, fen, marsh Chalk headwaters Springs polygon being mapped separately where the size Species data and swamp make up relatively small percentages of Chalk rivers Purple moor grass and rush pasture conformed to the minimum mappable unit. the land but play an important local role for a number Standing open water and canals Acid grassland of rare species. In the south of the county, European Codes were assigned based on available data, Ground Truthing level designated Special Areas of Conservation (SAC) Mesotrophic standing water Lowland dry acid grassland including site survey information generated via other contain prime examples of lowland beech and yew Eutrophic standing water Calcareous grassland habitat classification systems such as National woodland and in the north of the county the Bracken Lowland calcareous grassland NVC/PH1 Survey Vegetation Classification (NVC) and Phase 1 (PH1). concentration of lowland fens and the Milton Keynes Arable and horticulture Improved grassland The IHS package includes a 'translation' tool allowing reedbeds are of particular significance. Grass and grass-clover leys Neutral grassland data capture from these systems into IHS. A record Ordnance Cereal crops Lowland meadow was made of the original data sources in the database Survey Map together with newly assigned IHS codes. Non-cereal crops incl woody crops Grassland Intensively managed orchards Dwarf scrub heath Aerial Photography Each polygon has an associated attribute table which Vineyards Wet heaths provides information about the polygon. This table Whole field fallow Lowland heathland includes the IHS codes assigned, data sources used to Geology Arable headland or uncultivated strip Broadleaved, mixed and yew woodland assign the codes, level of confidence in code Fen, marsh and swamp Mixed woodland assignment as well as interpretation and general comments. Swamp Scrub woodland Reedbeds Broadleaved woodland Marginal and inundation vegetation Beech and yew woodland Fens Lowland beech and yew woodland Lowland fens Wet woodland Lowland mixed deciduous woodland Land Cover Coniferous woodland

Page 6 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 7 Overview Methodology Overview Buckinghamshire and Milton Keynes Habitat Types

Page 6 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 7 Part 2: Results - Habitats Lowland Calcareous Grassland Results - Habitats Lowland Calcareous Grassland

than 1% of the habitat extent in England but the Buckingham Milton Keynes 2.76 1% occurrence of much of the grassland in association with mosaics of scrub and woodland make it of high South Bucks 5.29 2% Winslow conservation value. Wycombe 199.55 58% The majority of this habitat occurs in the Chilterns Total 344.18 100% Area of Outstanding Natural Beauty, notably on the Chilterns escarpment. Smaller fragments of habitat Ludgershall Pitstone Percentage coverage of resource within are occasionally found on the limestone in north Bucks and MK: 0.18% Aylesbury Bucks and Milton Keynes. The average parcel size of this habitat is 3-4ha. Haddenham Wendover South Bucks Chiltern Milton Keynes Outside Designated Area As a result of agricultural intensification operations, 2% <1% 1% Princes Risborough 4%

much of the remaining grassland is confined to steep Chesham slopes; with 55% found on slopes greater than 13 Amersham degrees. The habitat mapping project has also revealed Stokenchurch that the bulk of sites are located on westerly aspects, Aylesbury Vale Within LWS 39% 33% Within SSSI of which 64% occur on Middle Chalk overlain with High Wycombe Wycombe 63% shallow lime-rich soils (83%). Beaconsfield 58%

Chalfont St. Peter Marlow Marlow Gerrards 218ha (63%) are found within SSSIs, another 33% falls Farnham Common Cross within LWS's leaving only 4% outside these designated areas. The management and designation of the habitat is important in conserving the resource as much

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815ha calcareous grassland is present of which 344ha grassland has been lost to agricultural intensification Location of Lowland is confirmed species rich lowland calcareous grassland and abandonment / scrub encroachment. In the Calcareous Grassland Olney accounting for 0.18% of the total habitat resource. Chilterns, grazing has traditionally maintained these in Bucks and MK Distribution Despite making up less than 1% of total land-cover it areas, but in recent years a reduction in livestock Hectares Percentage represents an important international habitat numbers and agricultural manpower has resulted in a resource and supports a number of rare species negative impact on some sites. Formalised grazing and Aylesbury Vale 135.57 39% including Chiltern Gentian, Juniper and the Striped scrub clearance is now an important conservation Milton Keynes Chiltern 1.00 <1% Lychnis Moth. The county's resource amounts to less management tool for this habitat. than 1% of the habitat extent in England but the Buckingham Milton Keynes 2.76 1% occurrence of much of the grassland in association with mosaics of scrub and woodland make it of high South Bucks 5.29 2% Winslow conservation value. Wycombe 199.55 58% The majority of this habitat occurs in the Chilterns Total 344.18 100% Area of Outstanding Natural Beauty, notably on the Chilterns escarpment. Smaller fragments of habitat Ludgershall Pitstone Percentage coverage of resource within are occasionally found on the limestone in north Bucks and MK: 0.18% Aylesbury Bucks and Milton Keynes. The average parcel size of this habitat is 3-4ha. Haddenham Wendover South Bucks Chiltern Milton Keynes Outside Designated Area As a result of agricultural intensification operations, 2% <1% 1% Princes Risborough 4% much of the remaining grassland is confined to steep Chesham slopes; with 55% found on slopes greater than 13 Amersham degrees. The habitat mapping project has also revealed Stokenchurch that the bulk of sites are located on westerly aspects, Aylesbury Vale Within LWS 39% 33% Within SSSI of which 64% occur on Middle Chalk overlain with High Wycombe Wycombe 63% shallow lime-rich soils (83%). Beaconsfield 58%

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species such as Sheep's-bit and Hornet Robberfly. Forty percent is located in SSSI's, with 47% located Buckingham Milton Keynes 1.97 6% There is clear evidence that the distribution of the within LWS, leaving 13% outside designated areas and grassland type is declining as historic maps indicate potentially vulnerable to further degradation. The South Bucks 0.97 3% Winslow much larger extents of this habitat in the past. main threat is encroachment by bracken and invading Wycombe 0.92 3% gorse and birch, making grazing and scrub clearance a Lowland dry acid grassland is mainly found in the primary tool in management efforts. Total 32.21 100% Greensand Natural Area located in the north of Aylesbury Vale and extending into Ludgershall Pitstone Percentage coverage of resource within Milton Keynes. Small areas are Bucks and MK: 0.02% Aylesbury also found in south Buckinghamshire. The average Haddenham size of this habitat is 2.3 ha Wendover South Bucks Milton Keynes Outside Designated Area which combined with its 3% 6% 13% Princes Risborough restricted distribution Wycombe Chesham 3% emphasises the vulnerability of Amersham this habitat type and the Stokenchurch species within it. Within SSSI Aylesbury Vale 40% High Wycombe 88% Beaconsfield Within LWS 47% Chalfont St. Peter Marlow Marlow Gerrards Farnham Common Cross

Page 10 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 11 Results - Habitats Lowland Dry Acid Grassland Results - Habitats Lowland Dry Acid Grassland

Lowland dry acid grassland is extremely rare and Results show that 46% is found on westerly facing Location of Lowland represents 0.02% of the total habitat resource in the aspects with a further 28% on south/south easterly Dry Acid Grassland Olney county, covering only 32ha in total. There is an in Bucks and MK aspects and a mean slope of 7 degrees. It occurs Distribution estimated 20,142ha of this habitat in England, mainly predominantly on Woburn Sand Formations with Hectares Percentage occurring in upland areas, of which the county total freely draining slightly acid sandy soils; elsewhere it is contributes less than 1%. Despite its low coverage in associated with gravels in the Thames Valley and Aylesbury Vale 28.34 88% relation to the national distribution, this habitat is other glacial deposits. Milton Keynes Chiltern 0 0% very important locally as it supports a number of rare species such as Sheep's-bit and Hornet Robberfly. Forty percent is located in SSSI's, with 47% located Buckingham Milton Keynes 1.97 6% There is clear evidence that the distribution of the within LWS, leaving 13% outside designated areas and grassland type is declining as historic maps indicate potentially vulnerable to further degradation. The South Bucks 0.97 3% Winslow much larger extents of this habitat in the past. main threat is encroachment by bracken and invading Wycombe 0.92 3% gorse and birch, making grazing and scrub clearance a Lowland dry acid grassland is mainly found in the primary tool in management efforts. Total 32.21 100% Greensand Natural Area located in the north of Aylesbury Vale and extending into Ludgershall Pitstone Percentage coverage of resource within Milton Keynes. Small areas are Bucks and MK: 0.02% Aylesbury also found in south Buckinghamshire. The average Haddenham size of this habitat is 2.3 ha Wendover South Bucks Milton Keynes Outside Designated Area which combined with its 3% 6% 13% Princes Risborough restricted distribution Wycombe Chesham 3% emphasises the vulnerability of Amersham this habitat type and the Stokenchurch species within it. Within SSSI Aylesbury Vale 40% High Wycombe 88% Beaconsfield Within LWS 47% Chalfont St. Peter Marlow Marlow Gerrards Farnham Common Cross

Page 10 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 11 Results - Habitats Lowland Beech and Yew Woodland Results - Habitats Lowland Beech and Yew Woodland

Lowland beech and yew woodland extends over 1196 Historically, many of these woodlands were a product Location of Lowland ha or 0.64% of the county and accounts for 4% of the of selective management regimes which favoured the Beech and Yew Olney resource nationally. The importance of these retention of maiden beeches, resulting in artificially Woodland in Distribution woodlands has been recognised at a European level dense stands of beech high forest. Through the late Bucks and MK Hectares Percentage and a number in the Chilterns are designated as 19th and 20th centuries a general decline in the SAC's. This type of woodland is particularly important demand for traditional wood products, changing Aylesbury Vale 186.85 16% for fungi and saproxylic invertebrates. In total, 36% of workforces, and the fluctuation in timber prices have Milton Keynes Chiltern 113.37 9% this habitat resource is located in SSSI's and another further influenced woodland management. Some have

51% in LWS, leaving 13% without any form of nature been converted to conifer plantations, some have Buckingham Milton Keynes 0 0% conservation designation. been abandoned, whilst others have maintained their character as mature stands of beech or 'hangars' for South Bucks 165.76 14% Winslow In Buckinghamshire this woodland type is which the Chilterns is famed. Policy in recent years concentrated across the Chilterns and south of the has once again begun to favour mixed broadleaved Wycombe 730.35 61% species through management schemes, thus county, including Burnham Beeches which is famed for Total 1196.33 100% its ancient pollards. The average size of the habitat is encouraging the re-emergence of less heavily managed 14ha with some of the smallest woods just 0.25 ha; beech and yew woodlands; although not necessarily of Ludgershall Pitstone Percentage coverage of resource within the habitat often being interspersed with other their former stature due to increased predation by Bucks and MK: 0.64% Aylesbury broadleaved woodland types and coniferous Grey Squirrel, Edible Dormouse and deer species. plantations. The mean Haddenham Wendover slope on which the South Bucks Aylesbury Vale Outside Designated Area habitat is found is 12 14% 13% Princes Risborough 16% degrees. Upper Chalk Chiltern Chesham 9% makes up 39% of the Amersham underlying geology Stokenchurch Within SSSI and 39% of woodlands 36% are found on shallow High Wycombe Beaconsfield Within LWS lime-rich soils over Wycombe 51% Marlow Chalfont St. Peter 61% chalk or limestone. Marlow Gerrards Farnham Common Cross

Page 12 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 13 Results - Habitats Lowland Beech and Yew Woodland Results - Habitats Lowland Beech and Yew Woodland

Page 12 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 13 Results - Habitats Lowland Meadow Results - Habitats Lowland Meadow

Neutral grassland covers 3,469ha with 11% of this The majority (56%) of lowland meadow is situated on Location of Lowland recognised as lowland meadow (382ha). Lowland slowly permeable seasonally wet slightly acid but Meadow in Olney base-rich loamy and clayey soils. meadow comprises 0.2% of the total county land area Bucks and MK Distribution and 3.6% of the total habitat resource in England. 89% Hectares Percentage of lowland meadow is located in the Vale, much of which is found in association Aylesbury Vale 340.76 89% with the floodplains of the Ray and Milton Keynes Chiltern 16.08 4% Upper Thames catchments.

Buckingham Milton Keynes 9.91 3% The average size of this habitat is around 7ha with the largest sites covering over South Bucks 6.69 2% Winslow 18ha and the smallest at less than 0.2ha. Wycombe 8.33 2% 14% of this grassland is designated as SSSI and a further 73% as LWS. These Total 381.77 100% designations act to prevent the loss of habitat through agricultural Ludgershall Pitstone Percentage coverage of resource within intensification and the change from Bucks and MK: 0.2% Aylesbury traditional practice of haymaking with aftermath grazing to silage production. Haddenham Wendover Species associated with this habitat type Milton Keynes Outside Designated Area Within SSSI South Bucks 3% include the rare Green-winged Orchid 13% 14% Princes Risborough 2% and several species of butterflies, such as Chesham Wycombe the Forester Moth. Amersham 2%

Stokenchurch Chiltern 4% High Wycombe Aylesbury Vale 89% Beaconsfield Within LWS

Chalfont St. Peter 73% Marlow Marlow Gerrards Farnham Common Cross

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Stokenchurch Chiltern 4% High Wycombe Aylesbury Vale 89% Beaconsfield Within LWS

Chalfont St. Peter 73% Marlow Marlow Gerrards Farnham Common Cross

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type is exemplified by their small size with some on slowly permeable seasonally wet slightly acid but Buckingham Milton Keynes 3.96 6% being less than 0.2ha. base-rich loamy and clayey soils. The underlying geology differs between numerous types but key are South Bucks 3.60 5% Winslow Ten percent of lowland fen fall outside designated glacial deposits formed during the ice age when areas, with 77% located within LWS and 13% in SSSIs. glaciers moved material to points beyond their Wycombe 0.42 1% Aylesbury Vale holds the majority of the county's original location. Total 67.10 100%

Ludgershall Pitstone Percentage coverage of resource within Bucks and MK: 0.04% Aylesbury

Haddenham Wendover Wycombe South Bucks Milton Keynes Outside Designated Area Within SSSI 1% 5% 6% 13% Princes Risborough 10%

Chesham Chiltern Amersham 4%

Stokenchurch

High Wycombe Aylesbury Vale Within LWS 77% Beaconsfield 84%

Chalfont St. Peter Marlow Marlow Gerrards Farnham Common Cross

Page 16 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 17 Results - Habitats Lowland Fen Results - Habitats Lowland Fen

Extending over only 67ha lowland fen represents less resource with 84% found mainly in the north east of Location of Lowland Fen than 1% of the national resource and covers less than the district. The lowland fens in the county support a in Bucks and MK Olney 0.05% of the total land area in the county. Lowland number of uncommon vascular plant species such as Distribution fen has been under considerable pressure from Bog Pimpernel. Hectares Percentage agricultural operations; their former extent is thought to have been far greater and notably drainage is a Fens form in areas which are difficult to drain. 31% of Aylesbury Vale 56.59 84% major contributing factor to their limited distribution fens are found on lime-rich loamy and clayey soils Milton Keynes Chiltern 2.53 4% across the county. The vulnerability of this habitat with impeded drainage and another 30% are found type is exemplified by their small size with some on slowly permeable seasonally wet slightly acid but Buckingham Milton Keynes 3.96 6% being less than 0.2ha. base-rich loamy and clayey soils. The underlying geology differs between numerous types but key are South Bucks 3.60 5% Winslow Ten percent of lowland fen fall outside designated glacial deposits formed during the ice age when areas, with 77% located within LWS and 13% in SSSIs. glaciers moved material to points beyond their Wycombe 0.42 1% Aylesbury Vale holds the majority of the county's original location. Total 67.10 100%

Ludgershall Pitstone Percentage coverage of resource within Bucks and MK: 0.04% Aylesbury

Haddenham Wendover Wycombe South Bucks Milton Keynes Outside Designated Area Within SSSI 1% 5% 6% 13% Princes Risborough 10%

Chesham Chiltern Amersham 4%

Stokenchurch

High Wycombe Aylesbury Vale Within LWS 77% Beaconsfield 84%

Chalfont St. Peter Marlow Marlow Gerrards Farnham Common Cross

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upon which this landscape type is found. Wood- Buckingham Milton Keynes 121.62 23% The loss of grazing and traditional tree management pasture and parklands are often remnants of former techniques and agricultural improvements has led to a medieval hunting forests, some with subsequent 16th South Bucks 41.97 8% Winslow decline of this habitat type. In contrast to other to 19th century designed landscapes incorporated, of habitats it is under represented and afforded little which many have now been converted to arable and Wycombe 96.15 18% recognition through existing processes. Only 8% and improved grassland. Total 529.91 100%

Ludgershall Pitstone Percentage coverage of resource within Bucks and MK: 0.28% Aylesbury

Haddenham Wendover Wycombe South Bucks Within SSSI Within LWS 8% 8% Princes Risborough 18% 4%

Chesham Chiltern Amersham 6%

Stokenchurch

High Wycombe Milton Keynes 23% Beaconsfield Aylesbury Vale Outside Designated Area 45% 88% Chalfont St. Peter Marlow Marlow Gerrards Farnham Common Cross

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Wood-pasture and parkland amounts to 529ha and 4% are designated as SSSI and LWS respectively, Location of Lowland makes up 0.28% of the county area and a significant leaving 88% without any formal nature conservation Wood-pasture and Olney 9% of the total habitat resource in England. 45% of designation. The disappearance of this habitat Parkland in Distribution the habitat is found within Aylesbury Vale while Milton threatens associated species such as the rare Oak Bucks and MK Hectares Percentage Keynes holds the second largest proportion at 23%. Polypore fungi which inhabits ancient trees. Wood-pasture and parkland is often defined by the Aylesbury Vale 236.11 45% presence of veteran trees and Burnham Beeches in Data reveals that lime-rich and clayey spoils with Milton Keynes Chiltern 34.05 6% south Bucks is a fine example of this landscape type. impeded drainage represents 33% of the substrate upon which this landscape type is found. Wood- Buckingham Milton Keynes 121.62 23% The loss of grazing and traditional tree management pasture and parklands are often remnants of former techniques and agricultural improvements has led to a medieval hunting forests, some with subsequent 16th South Bucks 41.97 8% Winslow decline of this habitat type. In contrast to other to 19th century designed landscapes incorporated, of habitats it is under represented and afforded little which many have now been converted to arable and Wycombe 96.15 18% recognition through existing processes. Only 8% and improved grassland. Total 529.91 100%

Ludgershall Pitstone Percentage coverage of resource within Bucks and MK: 0.28% Aylesbury

Haddenham Wendover Wycombe South Bucks Within SSSI Within LWS 8% 8% Princes Risborough 18% 4%

Chesham Chiltern Amersham 6%

Stokenchurch

High Wycombe Milton Keynes 23% Beaconsfield Aylesbury Vale Outside Designated Area 45% 88% Chalfont St. Peter Marlow Marlow Gerrards Farnham Common Cross

Page 18 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 19 Results - Habitats Lowland Heathland Results - Habitats Lowland Heathland

Although the county is not renowned for heathland Three quarters of lowland heathland is found on Location of Lowland on a national scale this is recognised locally as a rare Ancestral Thames River Terrace Deposits in the Heathland in Olney and important habitat. 83ha of lowland heathland has south of the county. The remaining areas are to be Bucks and MK Distribution been recorded, making up 0.04% of the land cover in found sporadically in the Chilterns on Clay with the county. This habitat is mainly found in small Flints and on the Greensands close to the Hectares Percentage isolated patches, reflecting its local rarity status. Bedfordshire border. The underlying soil is primarily Aylesbury Vale 8.71 10% Formerly more widespread across the county the (75%) slowly permeable, seasonally wet, acid loam Milton Keynes Chiltern 1.30 2% remaining areas receive special management attention; and clays. declines locally mirror those at a national scale with Buckingham Milton Keynes 0.51 <1% 84% of heathland in England lost since 1800. Several characteristic species are associated with the habitat South Bucks 62.43 75% including Heather and Gorse as well as a number of Winslow breeding birds such as Woodlark and Nightjar. Wycombe 10.44 13% Total 83.39 100% The majority of lowland heathland (95%) is found Ludgershall Pitstone Percentage coverage of resource within within SSSIs, another 2% is Bucks and MK: 0.04% Aylesbury associated with LWS leaving 3% outside designated areas. Haddenham Former areas of heathland Wendover Milton Keynes Chiltern Aylesbury Vale Within LWS Outside Designated Area have been lost due to 2% 10% 2% 3% Princes Risborough <1% woodland development and Chesham reflect the decline in Amersham traditional grazing and Wycombe Stokenchurch management practices in the 13% 20th century. High Wycombe Beaconsfield South Bucks Within SSSI 95% Chalfont St. Peter 75% Marlow Marlow Gerrards Farnham Common Cross

Page 20 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 21 Results - Habitats Lowland Heathland Results - Habitats Lowland Heathland

Page 20 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 21 Part 3 Results - Administrative Areas: Aylesbury Vale Results - Administrative Areas: Aylesbury Vale

Key Features Broad Habitats (ha) in Aylesbury Vale District (AVD) Lowland fen is a scarce resource Calcareous Dwarf Coniferous throughout the county, which in total Standing and Priority Habitat Type Area (ha) % of % of county total grassland shrub heath woodland only holds 67ha, with 57ha found in running water AVD present in district Bracken 303.87 1.83 514.05 474.05 Aylesbury Vale. 6% of the lowland fen 23.96 Chalk rivers 0 0 0 situated in the district falls outside Broadleaved, mixed Fen, marsh designated areas, with 6% and 88% and yew woodland and swamp Coastal and floodplain grazing marsh 226.62 0.25 62 83.52 located within SSSIs and LWS respectively. 4377.87 Eutrophic standing waters 19.86 0.02 100

Acid grassland covers 95ha with over Lowland beech and yew woodland 186.85 0.21 16 28% considered species-rich lowland Lowland calcareous grassland 135.57 0.15 39 dry acid grassland, and is found mainly Arable Improved grassland 34292.89 38618.39 Lowland dry acid grassland 28.34 0.03 88 on the Greensand Ridge. 31% of lowland dry acid grassland is situated inside SSSIs, Lowland fens 56.59 0.06 84 with another 53% found within LWS. Lowland heathland 8.71 0.01 10 Lowland meadow 340.76 0.38 89 226ha of floodplain grazing marsh exist here, making up 62% of the total county resource. Lowland mixed deciduous woodland 641.44 0.71 38 Acid grassland The majority of this habitat type is found in Neutral grassland Lowland wood-pasture and parkland 236.11 0.26 45 95.54 association with the Upper Ray catchment. 2220.51 Purple moor grass and rush pasture 3.92 <0.01 22

Much of the district is of a rural nature with the Reedbeds 7.93 0.01 32 Lowland wood-pasture & parkland Percentage of priority habitats within designated majority of the land cover being arable (38%) and Lowland heathland sites in Aylesbury Vale District Wet woodland 5.53 0.01 17 improved grassland (over 46%). Lowland fen Lowland meadow Lowland beech & yew woodland Total 1898.24 2.10 39 Outside Lowland dry acid grassland Designated Area Within SSSI Lowland calcareous grassland 25% 28%

Within LWS 47%

Page 22 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 23 Part 3 Results - Administrative Areas: Aylesbury Vale Results - Administrative Areas: Aylesbury Vale

Within LWS 47%

Page 22 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 23 Results - Administrative Areas: Chiltern Results - Administrative Areas: Chiltern

Key Features Broad Habitats (ha) in Chiltern District (CD) Broadleaved and coniferous woodland account for Priority Habitat Type Area (ha) % of % of county total nearly 15% land cover in Chiltern, of which 1.7% Calcareous Coniferous Dwarf Standing and is species-rich woodland, made up of lowland grassland woodland shrub heath running water CD present in district mixed deciduous (220ha) and lowland beech 33.97 388.42 1.30 61.30 Chalk rivers 25.63 0.13 35 and yew woodland (113ha). Fen, marsh and swamp Coastal and floodplain grazing marsh 0 0 0 2.53 Lowland mixed deciduous woodland Broadleaved, mixed Eutrophic standing waters 0 0 0 equates to 13% of the county resource and yew woodland Lowland beech and yew woodland 113.37 0.58 9 of which only 3% is found outside protected 2501.07 areas, with 44% located in SSSIs and 53% in LWS. Lowland calcareous grassland 1 0.01 0

Arable Improved grassland Lowland dry acid grassland 0 0 0 21% of lowland beech and yew woodlands are 5188.16 6462.88 4 located outside designated areas, none are found Lowland fens 2.53 0.01 within SSSIs and 79% are designated as LWS. Lowland heathland 1.30 0.01 2 Lowland meadow 16.08 0.08 4 Although major concentrations of specific habitats are absent, several types of priority habitat are Lowland mixed deciduous woodland 219.75 1.12 13 represented including lowland fen, lowland Acid grassland Neutral grassland Lowland wood-pasture and parkland 34.05 0.17 6 heathland and lowland meadow. 11.84 104.60 Purple moor grass and rush pasture 0 0 0

Of particular importance are the chalk rivers; Reedbeds 0 0 0 Lowland wood-pasture & parkland Percentage of priority habitats within designated both the Chess and the Misbourne run though 0 Lowland heathland sites in Chiltern District Wet woodland 0 0 the area, resulting in 35% of the total chalk river Lowland fen habitat resource in the county being located here. Lowland meadow Total 413.71 2.11 9 Lowland beech & yew woodland Outside The majority of land is under arable and improved Lowland dry acid grassland Designated Area Within SSSI grassland which accounts for 26% and 33% Lowland calcareous grassland 20% 26% respectively of total land cover. Within LWS 54%

Page 24 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 25 Results - Administrative Areas: Chiltern Results - Administrative Areas: Chiltern

Page 24 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 25 Results - Administrative Areas: Milton Keynes Results - Administrative Areas: Milton Keynes

Key Features Broad Habitats (ha) in Milton Keynes (MK) Milton Keynes holds a diverse mix of habitats, including a high proportion of species-rich habitat. Calcareous Coniferous Dwarf Standing and Priority Habitat Type Area (ha) % of % of county total 49% of all reedbed habitat in the county is found Bracken grassland woodland shrub heath running water MK present in district here, the majority of which is located outside 5.94 51.90 277.02 0.51 556.79 Chalk rivers 0 0 0 protected areas (88%). However, overall this Broadleaved, mixed Fen, marsh is a scarce habitat type covering only 12ha. and yew woodland and swamp Coastal and floodplain grazing marsh 84.43 0.27 23 1162.61 22.70 Eutrophic standing waters 0 0 0 23% of floodplain grazing marsh in the Lowland beech and yew woodland 0 0 0 county is found here and is primarily Improved grassland associated with the River Ouse. The entire 5837.91 Lowland calcareous grassland 2.76 0.01 1 extent of this habitat falls outside protected Arable Lowland dry acid grassland 1.97 0.01 6 areas. 13033.11 Lowland fens 3.96 0.01 6 120ha of lowland wood-pasture and parkland Lowland heathland 0.51 <0.01 <1 is located here and represents 23% of the Lowland meadow 9.91 0.03 3 total county resource, none of which is Neutral Lowland mixed deciduous woodland 257.82 0.83 15 covered by nature conservation designations. grassland Acid grassland 648.50 Lowland wood-pasture and parkland 121.62 0.39 23 Generally, arable land accounts for the majority of 2.42 Purple moor grass and rush pasture 3.99 0.01 22 land in rural Milton Keynes, second by improved Reedbeds 11.99 0.04 49 grassland. Woodland cover is low; at less than 4% Percentage of priority habitats within designated it is well below the county average of 9%. sites in Milton Keynes Wet woodland 0.87 <0.01 3

Lowland wood-pasture & parkland Lowland heathland Total 499.85 1.60 10 Lowland fen Outside Designated Area Lowland meadow 59% Lowland beech & yew woodland Within SSSI Lowland dry acid grassland 6% Lowland calcareous grassland Within LWS 35%

Page 26 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 27 Results - Administrative Areas: Milton Keynes Results - Administrative Areas: Milton Keynes

Page 26 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 27 Results - Administrative Areas: South Bucks Results - Administrative Areas: South Bucks

Key Features Broad Habitats (ha) in South Bucks District (SBD) South Bucks is of particular importance for heathland. The habitat is rare across the Coniferous Dwarf Standing and Priority Habitat Type Area (ha) % of % of county total woodland shrub heath county and the district holds 75% of the running water SBD present in district 169.65 62.44 184.56 total lowland heathland resource, the Calcareous grassland Chalk rivers 24.83 0.18 33 majority of which is found within Burnham 7.56 Fen, marsh Beeches, Stoke Common and Black Park and swamp Coastal and floodplain grazing marsh 0 0 0 13.32 Country Park. All lowland heathland is Eutrophic standing waters 0 0 0 included within SSSI's. Broadleaved, mixed Lowland beech and yew woodland 165.76 1.17 14 and yew woodland 59% of wet woodland in the county is 2643.05 Lowland calcareous grassland 5.29 0.04 2 found here and covers less than 20ha Improved grassland 4602.24 Lowland dry acid grassland 0.97 0.01 3 making it an extremely restricted habitat Lowland fens 3.6 0.03 5 type. Virtually the entire habitat is Arable located within LWS (62%) and 1756.66 Lowland heathland 62.43 0.44 75 SSSIs (35%) leaving only 3% outside Lowland meadow 6.69 0.05 2 protected areas. Lowland mixed deciduous woodland 275.49 1.95 16 A number of high value lowland wood- Acid grassland Neutral grassland Lowland wood-pasture and parkland 41.97 0.30 8 39.58 219.93 pasture and parkland sites are located in the Purple moor grass and rush pasture 5.27 0.04 29 southern part of the district associated with old Reedbeds 4.44 0.03 18 common land, heathland and parklands. Percentage of priority habitats within designated sites in South Bucks District Wet woodland 19.31 0.14 59 12% of the land cover is arable compared to the average county distribution of 34%, while Lowland wood-pasture & parkland Within LWS Lowland heathland 14% Total 616.06 4.36 13 improved grassland accounts for 34% Lowland fen Lowland meadow Broadleaved woodland occupies 19% and is well Lowland beech & yew woodland Within SSSI Outside Lowland dry acid grassland above the 9% county average for this habitat type. 78% Designated Area Lowland calcareous grassland 8%

Page 28 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 29 Results - Administrative Areas: South Bucks Results - Administrative Areas: South Bucks

Page 28 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 29 Results - Administrative Areas: Wycombe Results - Administrative Areas: Wycombe

Key Features Broad Habitats (ha) in Wycombe District (WD) With over 5000ha of broadleaved woodland, Priority Habitat Type Area (ha) % of Wycombe is of particular importance for this Calcareous grassland Coniferous woodland Standing and % of county total habitat. Lowland beech and yew woodland totals 418.21 613.81 running water WD present in district 730ha making the district a stronghold with over 166.72 Chalk rivers 23.60 0.07 32 60% of the total habitat resource found here, a Bracken Fen, marsh 25.23 and swamp Coastal and floodplain grazing marsh 52.03 0.16 14 proportion of which is included in the Chilterns 6.44 Beechwood SAC. Eutrophic standing waters 0 0 0 Broadleaved, mixed Lowland beech and yew woodland 730.35 2.25 61 Wycombe contains half of all calcareous grassland and yew woodland 5285.43 in the county (419ha); of which 200ha is species- Lowland calcareous grassland 199.55 0.61 58 Improved grassland rich lowland calcareous grassland. 9195.48 Lowland dry acid grassland 0.92 <0.01 3 Lowland fens 0.42 <0.01 1 At a county level, 58% of all lowland calcareous Arable grassland is found here making it an important 9148.74 Lowland heathland 10.44 0.03 13 stronghold for this habitat. The majority of sites Lowland meadow 8.33 0.03 2 are located along the Chiltern escarpment and on steep valley side slopes in the Radnage and Lowland mixed deciduous woodland 300.24 0.93 18

Bradenham Valleys. Acid grassland Neutral grassland Lowland wood-pasture and parkland 96.15 0.30 18 21.16 275.85 Purple moor grass and rush pasture 4.83 0.01 27 Almost half of the lowland calcareous grassland is found within SSSIs, with another 48% located in Reedbeds 0.32 <0.01 1 Lowland wood-pasture & parkland Percentage of priority habitats within designated LWS, leaving only 5% outside designated areas. Lowland heathland sites in Wycombe District Wet woodland 7.17 0.02 22 Lowland fen Overall, arable and improved grassland make up Lowland meadow Lowland beech & yew woodland Total 1434.36 4.42 30 the majority of land cover with 56%. Outside Within SSSI Lowland dry acid grassland Designated Area 30% Lowland calcareous grassland 24%

Within LWS 46%

Page 30 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 31 Results - Administrative Areas: Wycombe Results - Administrative Areas: Wycombe

Within LWS 46%

Page 30 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 31 Part 4: Using Bucks and MK Habitat Mapping Further Information Contents of Technical Appendices Acknowledgements

Possible Applications Technical methodology and appendixes are available via the This report was written and produced by Mai Nielsen and Environment pages on Buckinghamshire County Council’s Andrew McVeigh. The project is indebted to a number of organisations and individuals who kindly offered their web site. Appendix 1 Project Methodology Detailed description of project method Buckinghamshire Landscape Information Climate change monitoring assistance. System (BLIS) Habitat change can be recorded and monitored for Full dataset and further background information are held The data forms an important baseline within BLIS, the purpose of identifying changes due to climate with the Natural Environment Team, Buckinghamshire We would like to thank BMERC for their involvement in the which aims to collate information on the county's change. Appendix 2 Data Tables Breakdown by habitat type and district County Council. Contact: preparation of the project, especially Martin Harvey for his environment in one, easily accessible place. development of the data-capture tool. Liz Biron at Somerset Environmental education Natural Environment Team, Environmental Record Centre for assistance and support in Development control and strategic planning The projects outcomes can be utilised in the class County Hall, Appendix 3 Data sources List of data used in creation of the habitat map the use of IHS. An instant source of habitat information, the data room and serve as a general information source for Aylesbury, offers a tool for development control and planning the public about their local environment. HP20 1UY Milton Keynes Council and Natural England provided funding purposes. Appendix 4 Attribute table Content of attribute table in GIS layer without which the project would not have been able to go E-mail: [email protected] ahead. Green infrastructure planning Provide a basis for planning of green infrastructure in We would also like to express our gratitude to the GIS team connection with development. Appendix 5 IHS codes List of codes utilised in the project Further details about IHS can be obtained from the SERC at Buckinghamshire County Council for their help in the website at http://ihs.somerc.co.uk/ various IT related challenges encountered throughout the Ecosystem service assessment project. In combination with other datasets it will enable in- depth analysis of the benefits and services provided Importantly, a special thanks to the people who carried out by our environment. the data collection and input, notably Anna Humphries, Sarah Illustration Acknowledgements and Copyright Wright, Catherine Whormsley and the team at Jacobs. Biodiversity action planning The GIS maps produced in this booklet Ordnance Survey © Crown Copyright. All rights reserved Informs action planning and underpins identification © Also, we wish to thank the many individuals who have kindly Buckinghamshire County Council Licence No. 100021529 2010 Imagery © GeoPerspectives.com and establishment of coherent and resilient ecological shared their knowledge of the county's habitats and wildlife. networks. Copyright and contributors of photographs and images are as follows: Phil Irving, Natural England, Julia Carey, Jez Elkin, Michelle Dublon, Mark Bailey, Matt Dodds, Andrew McVeigh, Form a basis for research Chilterns Conservation Board, ESRI, Terry Longley and www.seeing.org.uk. All other photographs and images The habitat map can stimulate and inform further © Buckinghamshire County Council research into the environment including land cover change and opportunity mapping. Text: Mai Nielsen and Andrew McVeigh © Buckinghamshire County Council

Page 32 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 33 Part 4: Using Bucks and MK Habitat Mapping Further Information Contents of Technical Appendices Acknowledgements

Page 32 Buckinghamshire and Milton Keynes Habitat Mapping Project Buckinghamshire and Milton Keynes Habitat Mapping Project Page 33 Lavendon

Olney

Hanslope Sherington

Milton Keynes

Buckingham

Little Brickhill

Winslow

Aylesbury Aston Clinton

Wendover Haddenham

Ellesborough Dunsmore

Princes Risborough Chesham Prestwood

Amersham Walters Ash

Stokenchurch Hazlemere Chalfont St Giles High Wycombe

Beaconsfield

Chalfont St Peter Bourne End Marlow Farnham Common Stoke Poges Burnham Iver