New Forest Natural Area Profile

Transcription

1 New Forest Natural Area Profile Jonathan Cox March 1997 Jonathan Cox Associates Fig House, Poles Lane Lymington Hampshire SO41 8AB Tel/Fax:

2 Contents 1. Context: Natural Areas and the UK Biodiversity Action Plan The New Forest Natural Area The Nature Conservation Interest of the Natural Area Physical Features Tertiary deposits Evolution of the Solent River and the Quaternary environment Modern coastal geomorphology Wildlife features - habitats Coastal habitats The Avon Valley Crown Lands, Commons and Manorial Wastes The wider New Forest Wildlife features - species Coastal species The Open New Forest The Avon Valley Species of the Wider New Forest Influences on the Nature Conservation Interest Influences of the physical environment Influences of past land use Influences of present land use The Crown Lands, Commons and Manorial Wastes The coast The Avon Valley The wider New Forest The Future Six Conservation Objectives for New Forest Natural Area...24 Appendix 1: Key habitats in New Forest Natural Area...31 Appendix 2: Key Species in New Forest Natural Area...32 Bibliography...33

3 1. Context: Natural Areas and the UK Biodiversity Action Plan In June 1992 the Prime Minister and over 150 Heads of State or Governments signed the Convention on Biological Diversity at Rio de Janeiro. They did so to express a shared belief that action must be taken to halt the world-wide loss of animal and plant species and genetic resources. At the same time they agreed to draw up national plans and programmes and to share resources to help implement them. This resulted in the first UK Biodiversity Action Plan, published in 1994 (Box 1). The Plan commits the Government to the objectives of the Convention but, just as its production required a wide ranging and vigorous contribution from people and organisations who care about our natural environment, so delivering it will require active participation. The Government can take a lead and establish a framework but whether, in the end we and our children enjoy a country which is richer or poorer in species and habitats depends on all of us (Department of the Environment, 1994). English Nature, as the government s statutory advisors on nature conservation in England, have a key role to play in stimulating action. The development of the Natural Areas concept is an important part of that role. (Box 2). A Natural Area is not a designation, but an area of the countryside identified by its unique combination of physical attributes, wildlife, land use and culture. These features give Natural Areas a sense of place and a distinctive nature conservation character which we can seek to sustain (EN, 1993) the concept is based on wide participation and enables us to Think Globally, Act Locally. Box 1: UK Goals, principles and objective Overall goal 1. To conserve and enhance biological diversity (the variety of life) within the UK and to contribute to the conservation of global biodiversity through all appropriate mechanisms. Underlying principles 1. Where biological resources are used, such use should be sustainable. 2. Wise use should be ensured for non-renewable resources. 3. The conservation of biodiversity requires the care and involvement of individuals and communities as well as Governmental processes. 4. Conservation of biodiversity should be an integral part of Government programmes, policy and action. 5. Conservation practice and policy should be based upon a sound knowledge base. 6. The precautionary principle should guide decisions. Objectives for conserving biodiversity 1. To conserve and where practicable enhance: 3

4 a) the overall populations and natural ranges of native species and the quality and range of wildlife habitats and ecosystems. b) internationally important and threatened species, habitats and ecosystems. c) species, habitats and natural and managed ecosystems that are characteristic of local areas. d) the biodiversity of natural and semi-natural habitats where this has been diminished over recent decades. 2. To increase public awareness of, and involvement in, conserving biodiversity. 3. To contribute to the conservation of biodiversity in a European and global scale. Box 2: The Natural Areas concept A Natural Area is a tract of countryside which can be identified by its physical, wildlife and land use features. Physical features are determined by geology, landform, soils, climate and drainage. Wildlife features are determined by the pattern of habitats and mix of flora and fauna. Land use features are derived from past and present management activities. 2. The New Forest Natural Area New Forest Natural Area occupies the western side of the Hampshire Basin between Southampton and Bournemouth. Salisbury Plain and the west Wiltshire Downs are to the north, the Dorset Heaths to the west and the Solent to the south. The South Coast Plain and Hampshire Lowlands Natural Area and Southampton Water border the New Forest to the east. At the core of the Natural Area are the Crown Lands, commons and Manorial Wastes of the New Forest. These include the open grazed Forest of heathland, wood pasture and Forest lawns and the silvicultural inclosures from which stock are generally excluded. The Crown Lands, commons and Manorial Wastes are bounded by the New Forest perambulation. The perambulation has historical significance in being the limit to which medieval forest law had jurisdiction. Today, the perambulation delimits the area within which commoners stock are depastured and within which they are contained by cattle grids and fencing. The Natural Area extends beyond the perambulation to incorporate the Avon Valley to the west, much of the coastal plain between Christchurch and Calshot Spit to the south and the urban fringe of Southampton Water, known as the Waterside, which borders the Natural Area to the east. For much of its history, the pastoral economy of the open New Forest relied upon this much wider area to support the commoners stock. Evidence of these links occur throughout the Natural Area in the form of old drove roads, linear commons and greens. Although their physical links with the open Forest are have often been lost, these features remain as important components of the Natural Area s identity. The New Forest Natural Area is underlain by the clays and sands of Tertiary deposits. These consist of a series of marine, non-marine and estuarine deposits of clays, clay marls and 4

5 sands. Overlying these, particularly in the south of the Natural Area are extensive sheets of more recent gravel and Brick Earth. Apart from a few of the strata, including the clay marls, the series of deposits making up the New Forest Natural Area tend to produce base poor, acidic soils. In general the drainage pattern of the Natural Area is determined by the three main drainage basins into which surface water flows. To the west of the Natural Area, the broad valley of the River Avon is fed by six streams flowing westwards from the New Forest. To the east, two further streams (The Bartley Water and Cadnam River) flow eastwards to the River Test and the upper reaches of Southampton Water. On the southern side of the Natural Area, a further three rivers flow into the Solent (The Lymington River, Beaulieu River and Avon Water). The New Forest Natural Area comprises a diverse and complex mosaic of landscape and habitat types. Open landscapes are provided by the broad flood plain of the River Avon, the open coastal marshes and extensive tracts of heathland. More intimate enclosed landscapes are provided by the countryside of villages, hedged lanes, small fields, and coppice woodlands, grazed wood pastures and forestry plantations. Within the open New Forest, the complex of heathland, mire and pasture woodland do not occur anywhere else on so large a scale and nowhere else do they occur in combination. Although it may appear to be wild, the area owes its character to the historic common grazing system that creates a landscape of unique identity and survives here in one of the last places in lowland Europe. Settlements within the open Forest are linked by a network of enclosed and unenclosed roads. Typically straight unenclosed roads cross the open heathland whilst complex networks of enclosed lanes are characteristic of the countryside around villages and hamlets. Wide, tightly grazed, grassy verges are a feature of both the enclosed and unenclosed roads in the open New Forest with commoner s stock roaming widely along enclosed country lanes, often several miles from the Crown Lands. The hinterland of the open New Forest has a varied settlement pattern. To the east, the Waterside has been heavily developed over the last 50 years and contains extensive new housing estates, power stations and the oil refinery at Fawley that dominates the skyline in the south-east of the Natural Area. These have been superimposed on an ecologically rich and varied countryside, relicts of which still remain. West of Key Haven, mid 20th century, cliff-top, bungalow style housing dominates the villages and towns that now extend to the edge of the Natural Area at Christchurch. 3. The Nature Conservation Interest of the Natural Area The nature conservation interest of New Forest Natural Area is concentrated in certain key physical and wildlife features, but is also derived from the great diversity of wildlife habitats and physical features that merge from one to another. Many of the key habitats and features are also important within Britain and Europe, (see appendix). To help define policies for the conservation of the New Forest, the key elements of the Natural Area must first be defined. 5

6 3.1 Physical Features Tertiary deposits The New Forest Natural Area forms part of a broad and shallow syncline (geological basin) known as the Hampshire Basin. The overall structure of the basin evolved during the Tertiary period (65-5 million years ago) in response to the stresses created by the building of the Alps. The Tertiary deposits were layed down in a variety of environments including shallow seas, estuaries, brackish lagoons and freshwater marshes and rivers deltas. These varied conditions resulted in the deposition of a wide variety of sediment types including clays, clay marls and sands. Those within the New Forest are mainly of Eocene age (approximately million years). Many of these are rich in fossils including bones of crocodiles, various other reptiles and early mammals. The marine deposits include a sequence of clays of international importance, including the Barton Formation, exposed in the cliffs between Highcliffe and Barton on Sea. The Barton on Sea locality gives its name to a division of the upper Eocene known at the Bartonian. This division is recognised globally and the rich molluscun and associated fossil faunas of the areas are therefore of very great importance to geological science Evolution of the Solent River and the Quaternary environment Gravels and other deposits of more recent Quaternary age (formed during the last 2 million years) cover the Tertiary deposits to a variable depth over much of the New Forest. These include wide spreads and terraces of river gravels deposited by ancient river systems such as the Solent River. This river, now drowned by the modern-day Solent and Southampton Water, once rose near Dartmoor and flowed eastward across the Natural Area before discharging into the English Channel. Sea level rise has now drowned the course of the river, allowing the sea to separate the Isle of Wight from the mainland. The terrace gravels deposited by the Solent River are rich in archaeology and have yielded evidence of early human occupation in the form of Palaeolithic (early stone-age) flint implements Modern coastal geomorphology The Natural Area contains many classic examples of coastal features and valuable opportunities to study modern coastal processes at work. Although much modified by coast defence works, the entrance to the Solent is guarded by the archetypal shingle feature of Hurst Spit, whilst further well developed coastal shingle features occur along Solent shore, for example at the entrance of the Beaulieu River and Southampton Water. On the more sheltered coasts, found in the lee of Hurst Spit and the shores of the Lymington River, Beaulieu River and Southampton Water, examples of saltmarshes of differing age and state of erosion occur. The low cliffs to the west of the Natural Area within Christchurch Bay and between the Beaulieu River and Southampton Water, provide important examples of an eroding coastline and act as a valuable source of sediment, feeding Hurst Spit and the sediment shores of the Solent. 6

7 Box 3: Key Physical Features Tertiary deposits. The exposures of these rocks, particularly those in the cliffs between Highcliffe and Milford-on -Sea, are of international importance. The study of these rock exposures provides an opportunity to understand the environment of the Natural Area some million years ago. The fossils found in these rocks are also of great interest and include fossil molluscs, mammals, birds and fish. Evolution of the Solent River and the Quaternary environment. River gravel terraces, deposited during the Quaternary period (last 2 million years) occur widely in the south of the Natural Area with nationally important exposures in the low cliffs between the Beaulieu River and Southampton Water and gravel pits in the open New Forest. These show features of the former Solent River and its tributaries and provide evidence of the environment and human occupation of the Natural Area in this period. Coastal processes. Sedimentary features such as shingle spits, beaches and saltmarshes and eroding coastlines, such as those in Christchurch Bay, provide classic examples of these features and opportunities to study modern coastal processes. 3.2 Wildlife features - habitats By necessity this review of the key wildlife habitats in the New Forest focuses on the those that are of greatest importance in a national and international context. These are concentrated in three particularly important regions of the Natural Area; The coast, The Crown Lands, commons and Manorial Wastes of the New Forest, The Avon Valley. In addition to these concentrations of important habitats, the wider countryside linking these regions also contains many important habitats, some of national importance, others of more regional or local significance Coastal habitats Fine examples of coastal grazing marshes occur within the Natural Area at the entrance to the Beaulieu River and between Hurst Spit and the Lymington River. Coastal grazing marshes were created by enclosure of estuarine saltmarsh and mudflat for agricultural purposes. Subsequent management by extensive grazing, without the application of herbicides or fertiliser, has created an intimate mix of grassland and saltmarsh vegetation types. These are characterised by the presence of several nationally rare and scarce plant species such as bulbous foxtail, divided sedge and a number of species of saltmarsh-grass. These flat, low-lying grasslands are drained by a network of brackish or freshwater drainage ditches and are important for aquatic invertebrates. Like the grassland vegetation, this fauna contains species of both fresh and brackish water environments and includes several species, particularly of water-beetle, that are virtually confined to this habitat. The wet grasslands associated with coastal grazing marshes are also important for breeding birds, particularly waders, whilst in winter they attract large numbers of waterfowl and wading birds. 7

8 Saline lagoons consist of shallow, open bodies of brackish or saline water, partially separated from the adjacent sea by a shingle, sand or artificial structures such as a sill or sea wall. Although all retain water at low tide, they exchange water with the sea via percolation, overtopping or via a direct inlet to the sea. The often widely fluctuating salinity levels found in saline lagoons create a habitat in which only a specialised group of plants and animals can survive. This includes a remarkable number of rare and scarce species given specific legal protection under the Wildlife and Countryside Act. Saline lagoons are a nationally and internationally rare and vulnerable habitat. They are listed as a priority habitat under Annex I of the EU Habitats Directive and as a key habitat of conservation concern in the UK Biodiversity Action Plan. The New Forest Natural Area contains one of the most important concentrations of this habitat in Britain. Many are manmade features derived from old oyster beds and saltworks whilst others are natural depressions within shingle beaches. Their important flora and fauna includes the foxtail stonewort, the shrimp Gammarus insensibilus, the worm Armandia cirrhosa and the starlet sea-anemone Nematostella vectensis. All four species are nationally rare and legally protected although Armandia cirrhosa has not been seen for several years and may now be extinct in Britain. Vegetated shingle features are rare and specialised habitats listed in Annex I of the EU Habitats Directive. Vegetated shingle features, are also key habitats of conservation concern in the UK Biodiversity Action Plan. Shingle spits and beaches are a characteristic habitat of the New Forest coast. The most extensive and well developed occur at the mouths of the main estuaries with particularly fine examples at the entrance to the Beaulieu River and on Hurst Spit, Calshot Spit and the relatively undisturbed shoreline between Lepe and Stanswood Bay. The vegetation of these shingle features is composed of a characteristic flora containing many nationally important species. The vegetation shows a distinct zonation related to the age of the shingle deposit. Nearer the sea, open shingle vegetation is often characterised by the presence of yellow-horned poppy, sea kale and the nationally rare little robin (a close relative of the common herb Robert). As the shingle becomes more stable acid grassland and heathland vegetation develops, these shingle heaths are also rich in lichens. Fine examples of this mature shingle vegetation occurs within the North Solent National Nature Reserve at the entrance to the Beaulieu River. The invertebrate fauna of shingle is also highly specialised and includes many species that are confined to this habitat. Disturbance from people and their dogs seriously limits the use shingle by nesting sea birds in the Natural Area. Where access to the public is controlled, as within the North Solent National Nature Reserve, the shingle beaches support nationally important populations of breeding sea birds including populations of four species of tern (all of which are internationally threatened and listed on Annex I of the EU Birds Directive) and nationally important populations of breeding black-headed gulls. Saltmarshes develop in the intertidal zone where there is an accumulation of fine sediments. Some degree of shelter is required for this accumulation, so saltmarshes are found in the 8

9 estuaries and within the lee of Hurst Spit. Saltmarshes support internationally important vegetation types, listed as being of Community Interest on Annex I of the EU Habitats Directive. Saltmarshes are also one of the 38 key habitats of special conservation importance listed in the UK Biodiversity Action Plan The largest saltmarshes in the Natural Area are found at the entrance to the Lymington River and within the lee of Hurst Spit. These saltmarshes are dominated by the cord-grass Spartina anglica. This relatively new species developed from the hybridisation of two other cordgrasses at the end of the last century. It was first discovered in Southampton Water and has since spread widely throughout the Britain. The longer established mixed vegetation of the mid and upper saltmarshes are much less common, but are well developed along the Beaulieu River and the upper reaches of Southampton Water near Marchwood. These mixed saltmarshes support the nationally scarce glasswort Salicornia pusilla. Sea level rise (both natural and man-induced) has caused much erosion of the saltmarshes in most of the Solent s estuaries, leaving them with characteristically eroded cliff edges. Further areas of saltmarsh have been lost as a result of marina development, port activities and associated infrastructure development. Saltmarshes have a vital role to play in the ecology of the estuaries. The high productivity of saltmarshes, in terms of biomass, can contribute a primary source of material for the complex food chains within an estuary. This is of particular importance to the internationally important populations of migratory wildfowl and waders attracted to overwinter on the highly productive mudflats found in the estuaries of the Natural Area. In summer, saltmarshes are also important for nesting birds, particularly waders. The highest densities of breeding redshank in Britain have been recorded from the saltmarshes of the western Solent. The inland edge of many of the Natural Area s saltmarshes are marked by transitions to reed beds. Although none of these are very extensive, they support populations of typical reed nesting birds including bearded tits, reed warblers and the secretative water rail. Some of the best developed areas of reed bed are found on the Beaulieu river and along the Avon Water at Keyhaven. The intertidal mudflats and sediment shores of the Natural Area are also of international importance to nature conservation. They support a rich flora including extensive beds of eel grass. These are composed of three Zostera species, all of which are nationally scarce. Sheltered brackish mudflats at the head of the Beaulieu River and within Christchurch Harbour also contain localised populations of the nationally rare dwarf spike-rush. The rich invertebrate fauna of the intertidal is also of considerable nature conservation importance, both in its own right and for the internationally important populations of wintering and migratory wildfowl and wading birds it supports. 9

10 Estuaries and eel-grass beds are included in the list of key habitats in the UK Biodiversity Action Plan. Estuaries and intertidal mudflats are also habitats of Community Interest, listed on Annex I of the EU Habitats Directive The Avon Valley The chalk river of the Avon is internationally important to nature conservation. In its upper reaches it is fed with clear, unpolluted spring water rising from Salisbury Plain. Lower down its course, it receives water from the acid catchments of the New Forest and Dorset heathlands. This range of water chemistry supports a very rich aquatic flora and fauna. The Avon also contains important examples of floating water-crowfoot vegetation, an internationally threatened habitat listed on Annex I of the EU Habitats Directive. Chalk rivers, such as the Avon, are included on the list of habitats of conservation concern in the UK Biodiversity Action Plan. The fauna of chalk rivers is important and includes several nationally rare invertebrate species, an important fish fauna containing internationally threatened species such as the Atlantic salmon and bullhead and internationally important species such as the otter. Although undergoing a rapid decline, the flood plain grasslands of the Avon valley are still nationally important for breeding wading birds and internationally important for wintering widlfowl. They also support a rich invertebrate fauna including many nationally rare and scarce species. Outside of the Crown Lands and commons of the New Forest, further areas of acid grassland occur, particularly on gravel terraces and areas of wind blown sand along the Avon valley and on mature shingle deposits on the coast. These acid grasslands also support a number of nationally rare and scarce species dependent upon grazing by stock and rabbits Crown Lands, Commons and Manorial Wastes The Crown Lands, commons and Monorial Wastes of the New Forest are of international importance to nature conservation. They contain large areas of four habitat types that are now fragmented and rare in lowland western Europe: Lowland heathland Valley and seepage-step mires Acid to neutral grasslands, including Forest lawns and greens Ancient wood pasture The New Forest Natural Area contains approximately 14,400 ha. of lowland heathland, one of the largest areas of this habitat in Europe. The New Forest heathland forms complex mosaics of vegetation type and includes grass heaths and acid grasslands, the botanical composition of which is related to soil structure, permeability and the effects of grazing. Dry heath, dominated by heather and bristle bent-grass occurs mainly on better drained hill tops and plateau s. This grades into humid heathland on more slowly permeable soils where cross-leaved heath and purple moor-grass are the predominant species. Unlike other lowland heaths in Britain, this humid heathland is extensive in the New Forest and forms the dominant heathland vegetation type. On the wetter peaty soils, where drainage is more impeded, 10

11 heather becomes less abundant and a mix of rushes and bog mosses become important components of the vegetation. The fauna associated with the New Forest s heathlands is rich and diverse and the extent of this habitat is probably large enough to ensure the long term survival of its characteristic fauna with a wide range of heathland micro-habitat types, whilst smaller, isolated and fragmented examples are more liable to biological impoverishment. Heathland is an internationally important habitat listed on Annex I of the EU Habitats Directive and a key habitat in the UK Biodiversity Action Plan. The New Forest contains about 90 clearly defined valley mires or bogs, within 20 different valley systems. More of this habitat survives in the New Forest than in the remainder of Britain and western Europe put together. This complex of mires sits within a relatively natural catchment largely unaffected by water abstraction and is of international importance to nature conservation. Valley mires are formed along the floor of valleys where drainage is impeded, resulting in the development of often deep peat deposits. The valley mires show an interesting transition of wetland vegetation types and associated flora from the edge of the mire through to its central core and from the head of the valley downstream. These transitions are related to level of alkaline chemicals and plant nutrients (bases) that accumulate in the core of the mire. The zonation from base enriched fen vegetation along the axis of the valley mires to acid mire at the outer margins, gives rise to a great diversity of plant species including many nationally rare, scarce and locally distributed species. Seepage-step mires are found on the valley sides where springs emerge, often at the junction of two underlying rock strata. Seepage-step mires often form complex mosaics of vegetation with associated wet and humid heathland and valley mire. The New Forest seepage-step mires are also very rich in plant species, again related to the level of base enrichment. In the south of the Forest, water arising at the junction of clay marls and overlying gravel deposits gives rise to a few strongly base enriched mires supporting a specialist fen vegetation whilst more commonly, acid mire vegetation occurs, dominated by bog mosses, sedges and rushes and insectivorous plants such as the sundews and butterworts. The mix of vegetation types found in seepage-step and valley mires includes several habitat types that are internationally rare and threatened and included on Annex I of the EU Habitats Directive. The New Forest contains extensive areas of agriculturally unimproved grassland occurring on broadly neutral to often strongly acidic soils. Most of the neutral grassland is concentrated in Forest lawns and village greens. The lawns form linear strips along streamsides and road verges whilst greens occur within and around settlements and as glades within pasture woodlands. The Forest lawns and greens are typically tightly grazed and often seasonally poached. A wide range of nationally rare and scarce plant species are associated with these grasslands, typically including extensive mats of the nationally scarce and threatened chamomile and nationally rare penny-royal mint. On more acid soils, a further range of grassland types is found. These occur on both wet and drier soils. As with the neutral grasslands, these are invariably tightly grazed and support a rich flora typified by species able to withstand the constant grazing pressure or which are unpalatable. 11

12 The woodlands of the New Forest Natural Area are of outstanding importance. Within the open New Forest, this includes about 4,600 hectares of grazed pasture woodland, dominated by oak, beech and holly, scrub and alder carr. The long history of traditional management of much of the New Forest s wood pasture has created an area that is considered one of the finest remnants of comparatively undisturbed deciduous forest in the lowlands of western Europe. Their ecological characteristics which give them national and international importance have been summarised as: Structural diversity, with a wide range of age class from saplings to fully developed, senile and dead trees. A wide range of density of trees from closed high canopy forest to open lawns and glades and the presence of extensive riverside woodlands. Relative lack of human interference with no consistent history of systematic harvesting of timber trees resulting in a continuity of structural diversity. An exceptionally rich lichen flora. An exceptionally rich invertebrate fauna. An exceptionally rich breeding bird fauna. An exceptionally rich bryophyte flora. An exceptionally rich fungal flora. Wood pasture is listed as one of the 38 key habitats of conservation concern in the UK Biodiversity Action Plan. Internationally important examples of lowland beech woodland, old oak woods on acid soils and riverine woodland on alluvial soils, occur within the New Forest s wood pastures. All these woodland types are rare and threatened in Europe and listed on Annex I of the EU Habitats Directive. The grazed, semi-natural (unplanted) woodlands of the New Forest are often termed Ancient and Ornamental (A&O) woodlands. This term, which is unique to the New Forest, is used to describe both ancient woodland, that has remained under woodland cover for at least the last 400 years and non-ancient secondary woodland that has developed in more recent times. Although much emphasis is often placed on the distinction between these two woodland types these are less important in the New Forest. Here the complex mosaic of open unwooded and wooded land allows plants and animals that are normally confined to ancient woodland to colonise more recent woodlands in a relatively short space of time. The term Ancient and Ornamental woodland therefore provides a better description of this collection of woodlands that display the range of characteristics listed above. In addition to the four key habitat divisions described above, the New Forest also contains nationally important examples of several other habitats. The streams and rivers draining the open New Forest, such as the Highland Water, are relatively undisturbed by river management and human disturbance and show a rich diversity of natural riverine features and processes. The combination of water from acid and more base enriched strata feeding these streams gives rise a rich plant diversity and a plant community which is restricted almost exclusively to the New Forest. The aquatic fauna of the New Forest s streams is also rich and includes twenty species of fish, a wide diversity of invertebrates including a thriving population of the internationally rare and threatened southern damselfly. This species is listed on Annex II of the EU Habitats Directive and is a key species of conservation concern in the UK Biodiversity Action Plan. Otters also use some of the New Forest streams. Of the many ponds in the Forest, the less acidic support important populations of amphibians, including the internationally threatened great crested newt. Temporary or ephemeral ponds 12

13 that dry out in summer provide specialist conditions for a number of nationally rare invertebrates including the only locality in Britain for the tadpole shrimp. The silvicultural inclosure woodlands, which occupy some 8,400 ha. of the Crown Lands, commons and Manorial Wastes, contain approximately 40% broadleaved woodland. This includes some significant fragments of relatively intact former pasture woodland, now trapped within the inclosure fences. Much of the remaining broadleaved woodland in the inclosures consists of mature oak plantation dating from the 17th century. Where these occur in proximity to ancient unenclosed woodlands, they are rapidly developing many of the attributes of pasture woodland. The broadleaved inclosure woodlands contrast with the Ancient and Ornamental woodlands in being subject to much lower grazing pressures. This allows the development of a contrasting ecology which includes a greater abundance of woodland butterflies The wider New Forest Outside of the Avon Valley and the open Forest and inland from the coast, there is a zone of countryside which is rich in many important wildlife habitats, species and features. This wider countryside also has important links with the ecology and land-use economy of the open New Forest. Outside of the open Forest, several important areas of heathland survive, particularly in the west of the Natural Area. Most of these heathlands were once linked to and grazed as part of the open Forest. Separation and lack of stock grazing now threatens some of these fragmented heathlands with scrub invasion and loss of micro-habitat, although recent initiatives have attempted to reverse this trend. In contrast to the heavily grazed grasslands of the open New Forest, enclosed meadows, in and around the Forest are quite numerous, if scattered and often isolated. As with the unimproved grasslands within the open Forest, these enclosed meadows show a great variety of type related to differences in soils and management regime. They include species of typical hay meadows such as green-winged orchids, wet marshy grasslands dominated by purple moor-grass and acid wet acid grasslands containing elements of a heathland flora. The woodlands, particularly the ancient semi-natural woodlands surrounding the open New Forest area also of considerable nature conservation value. Like the heathlands, these woods include several extensive areas of former wood pasture, particularly to the north of the Forest, that have been fragmented from the open New Forest in recent decades. By contrast to these former wood pastures, the countryside surrounding the open Forest includes many typical ancient coppice woodlands. These have been traditionally managed with the exclusion of stock grazing to promote the growth of regularly cut coppice. The flora and fauna of these copses is typically rich and includes a number of woodland plants and animals that are rare or absent from the grazed woods. Some of outstanding examples of these ancient coppice woodlands occur fringing the saltmarshes of the Beaulieu River and Southampton Water. They show remarkable transitions from ancient woodland through saltmarsh to mudflats which are of considerable nature conservation interest and form components of a suite of such woodlands that fringe the estuaries of the Solent. 13

14 Concentrations of rare and uncommon plants and animals are found within the semi-natural habitats described above but these habitats do not exist in isolation. The quality of the landscape in which they occur is important in ensuring their conservation. Moreover, the wider countryside also supports a wealth of wildlife within the complex of hedges, permanent pastures and arable farmland that occurs within the Natural Area. This includes populations of several species, such as the brown hare, skylark and grey partridge, that are in national decline, mainly due to the effects of agricultural intensification. Box 4: Key wildlife features - habitats Coastal Habitats: The coast of the Natural Area is extremely diverse and includes examples of several internationally important habitats including significant areas of saltmarsh, saline lagoons, vegetated shingle and coastal grazing marshes. This diversity of coastal habitats supports a rich fauna and flora including many nationally rare and scarce species. The coastal habitats of the Natural Area often fringe extensive intertidal sand and mudflats. This combination of estuarine and marine habitats is of outstanding nature conservation importance. The Avon Valley: The River Avon is a chalk river of international importance. It supports a rich aquatic flora and fauna including several nationally rare and declining species. The River Avon is also of importance for several key wetland and aquatic species. The flood plain of the River Avon supports some extensive areas of agriculturally unimproved flood plain grassland whilst the freely draining gravel terraces support examples of nationally important areas of acid grassland with rich floras that include several nationally rare plant species. The Open New Forest: The open Forest includes extensive areas of lowland heathland, valley and seepage-step mire, Forest lawns and greens and ancient pasture woodland. These are all internationally important and threatened habitats. Nowhere else in lowland western Europe do they occur on such a large scale or in combination. In addition the New Forest contains nationally important examples of ponds, rivers and acid grassland. The wider New Forest: The wider countryside that links the three regions of the Natural Area described above contains many important semi-natural habitats including; lowland heath, former wood pasture, ancient coppice woodlands and many agriculturally unimproved grasslands. In addition, the enclosed countryside within and around the open Forest is rich in wildlife dependent upon the mix of hedges and hedgerow trees, ponds and streams, permanent pastures and even arable fields. 3.3 Wildlife features - species The wide range of wildlife habitats within New Forest Natural Area provides a home for a large number of plants and animals, both common and rare. Appendix 2 lists those species that are subject to special legal protection, are internationally important or included on the short list of species in the UK Biodiversity Action Plan. This section aims to highlight just a few of the species and groups that are characteristic of the Natural Area Coastal species On the coast, one of the greatest concentrations of rare species is found in the saline coastal lagoons. Eight Acre pond, near Lymington, is a particularly rich example containing the nationally rare foxtail stonewort. The invertebrate fauna is also rich in specialist and nationally rare species including the starlet sea-anemone, the shrimp Gammarus insensibilis and the globally rare worm Armandia cirrhosa (last recorded at Eight Acre Pond in 1992) 14

15 The wide diversity of other coastal habitats present in the Natural Area are also important for a number of rare and uncommon plants. The nationally rare little robin is found on shingle beaches whilst the equally rare small spike-rush can be found in the Mill Pond at Beaulieu on brackish mudflats. Within coastal grazing marshes nationally uncommon plants include the annual beard-grass and sea barley and on sea walls plants such as slender hares-ear and curved hard-grass. The coastal habitats are also of national and international importance for birds. The intertidal mudflats and their fringing saltmarshes and coastal grazing marshes attract internationally important populations of wintering and passage wildfowl and wading birds. In summer the secluded shingle shores of the Natural Area, such as at the mouth of the Beaulieu and Lymington Rivers, attract nationally important populations of breeding sea birds, including the internationally threatened common tern, little tern, roseate tern and sandwich tern. Vegetated shingle and saltmarshes also support a specialist invertebrate fauna that includes many nationally rare and endangered species The Open New Forest The open New Forest contains probably the most important concentration of rare, scarce and locally distributed species in Britain. This is summarised below: Pasture woodland Rich fungi flora including species that are specific to pasture woodland Richest woodland lichen flora in lowland Europe, including rare species such as Catillaria laureri and Parmelia minarum Rich bryophyte flora including rare species such as Bassania trilobuta and Saccogyna viticulosa. Rich vascular flora including at least 60 species considered indicative of ancient woodlands. Exceptionally rich dead-wood invertebrate fauna including nationally rare species such as stag beetle Only population of the New Forest cicada Cicadetta montana in Britain High densities of hole and crevice nesting woodland birds Important bat roosts including the rare Bechstein s bat. Heathlands Rich lichen flora on dry heath includes nationally scarce Cladonia incrassata Important fungi including nationally rare nail fungus Poronia punctata Bracken stands on the edge of the heathland supports wild gladiolus in its only location in Britain, other rare vascular plants include heath lobelia. Nationally rare sand lizard and smooth snake occur in areas of mature dry heath 15

16 Internationally important breeding bird populations include largest number of breeding Dartford warbler in Britain and nationally important populations of breeding nightjar and woodlark. Other species listed on Annex I of the EU Birds Directive include breeding Montagu s harrier and wintering hen harrier. Grasslands Important flora including nationally rare: penny royal mint, small fleabane, slender bedstraw and nationally scarce yellow century, chamomile and all-seed. Valley and seepage mires Rich flora including nationally rare slender cotton-grass and nationally scarce pillwort, bog orchid, bog hair-grass, brown beak-sedge, marsh gentian and marsh clubmoss. Important assemblage of breeding waders, including snipe, redshank, curlew and lapwing. Important invertebrate fauna including the nationally rare bog ant. Ponds and streams Includes populations of internationally threatened southern damselfly, tadpole shrimp and nationally rare fairy shrimp and medicinal leech The Avon Valley Rich flora including nationally rare Hampshire purslane Rich fish fauna with over 20 species recorded. Breeding kingfisher, a species listed on Annex I of the EU Birds Directive Otters still occur within the Avon Valley, nationally and internationally the otter is a threatened and vulnerable species. It is listed on Annex II of the Habitats Directive as a species of community Importance and is given full legal protection in Britain being listed on Schedule 5 of the Wildlife and Countryside Act. Water voles are still widespread on the River Avon but nationally they have undergone a rapid decline. Like the otter, the water vole is also listed in the UK Biodiversity Action Plan as being of conservation concern. The River Avon supports important populations of internationally threatened fish species including Atlantic salmon, bullhead, sea lamprey, brook lamprey and river lamprey. All are listed on Annex II of the EU Habitats Directive as species requiring specific conservation measures. The wintering bird fauna of the Avon Valley is internationally important and includes internationally important populations of wintering Bewick s swan and gadwall, nationally important numbers of wintering European white-fronted geese and important populations of breeding redshank, snipe, lapwing and Cetti s warbler. The invertebrate fauna of the valley has only been superficially studied but is know to support an important mollusc fauna including the nationally rare Valvata macrostoma and Psidium tenulineatum. 16

17 The flora of the Avon Valley is also rich, particularly that associated with the gravel valley terraces and areas of wind-blow sand. These support populations of the nationally rare brown galingale around grazed pond margins and small fleabane on cattle poached tracks. Nationally scarce species are also abundant with particularly important populations of suffocated clover and mossy stonecrop Species of the Wider New Forest In the wider New Forest a further group of important key species occur. This mixed landscape of hedges, small fields and copses still supports strong barn owl populations. In addition, the more base enriched ponds often contain great crested newts. The ancient coppice woodlands are important for the nationally rare and protected dormouse. These ungrazed woodlands, particularly on the larger private estates also retain a rich butterfly fauna including nationally threatened species such as the pearl-bordered fritillary. Nationally declining species such as brown hare, grey partridge and skylark are all still widespread in the wider countryside. Box 5: Key wildlife features - species (see also Appendix 2) Mammals: The river Avon and streams within the open New Forest support otter populations. Several of the rivers in the Natural Area also support populations of water vole whilst the ancient semi-natural woodlands, particularly those on the fringes of the open Forest retain populations of dormice. Birds: The coastal habitats of the New Forest are internationally important for wintering and passage wildfowl and wading birds. In addition, the coastal wetlands and shingle deposits are of international importance for breeding terns. The open New Forest supports internationally important heathland breeding bird populations including nightjar, woodlark and Dartford warbler. The Avon Valley and wetlands within the open Forest are nationally important for breeding waders of wet grassland. The Avon Valley also attracts internationally important populations of wintering waterfowl. Invertebrates: The coastal saline lagoons are of outstanding importance for rare invertebrate species. The open New Forest has an outstanding invertebrate fauna, particularly associated with its pasture woodlands, heathlands, ponds and streams. The Avon Valley has a rich aquatic fauna although this is very under-recorded. Plants: The Natural Area is rich in nationally and internationally rare plant species. The lower plant flora of the pasture woodlands includes the richest woodland lichen flora in lowland Europe and nationally important bryophyte and fungi floras. The vascular flora of the Forest s heaths, mires and grasslands are particularly rich in nationally rare and scarce species. On the coast important habitats for rare and scarce plants include areas of vegetated shingle, saline lagoons and grazing marshes. The Avon Valley is also rich in important plant species, particularly the gravel terraces and areas of windblown sand that fringe the valley sides. 4. Influences on the Nature Conservation Interest The nature conservation interest of New Forest Natural Area is a product of its physical environment and its long history of human settlement and exploitation. The physical features of the Natural Area, such as its climate, geology, drainage and topography, have influenced the vegetation and its associated flora and fauna. Humans have influenced, and continue to influence, the vegetation and species through agricultural, forestry, recreation and commercial activities. 17

18 4.1 Influences of the physical environment The location of the Natural Area within the warm climate of central southern England has a significant influence on the range of plants and animals it supports. Here, species from the mild and moist west of Britain reach the eastern limit of their range whilst others from the drier continental climate of the east of Britain reach the western edge of their range. The biodiversity of the Natural Area is also influenced by the variety of soil type and coastal features it contains. In the open New Forest this includes the acid sands, gravels and stagnogleys and the more base enriched soils associated with the marl clays of the Headon Beds. The ground water levels associated with these differing soils and the development of podsols and forest brown earth soils in undisturbed conditions adds even further diversity to the range of soil conditions and associated habitats that can be found. On the coast, differing influences of salinity combined with variations in substrate age and types creates a wide range of habitats. In the Avon Valley further curious soil types and habitats occur as gravels and wind-blown sands merge into valley alluvial deposits. These are flushed with water of differing chemistry ranging from the chalk river water to the acid water arising from the gravel terraces and streams draining the New Forest and Dorset heaths. The distribution and maintenance of coastal habitat diversity is dependent upon the continual effects of coastal erosion, sediment transport and deposition. The interruption of these natural coastal processes with sea defences seriously threatens the diversity of coastal habitats and species. Rising sea levels also represent a key threat to the future of coastal wildlife. As sea levels rise, coastal habitats would naturally migrate inland to replace terrestrial habitats. With the widespread development of sea walls and other coast defence structures, this natural response is seriously constrained so that intertidal habitats are becoming squeezed out between rising sea levels and an immovable line of coast defences. The importance of the River Avon is dependent upon the continual supply of unpolluted chalk spring water arising from the huge underground reservoir or aquifer held under Salisbury Plain. Exploitation of the aquifer to supply drinking water and threats to water quality from agricultural run-off and sewage effluent discharges threatens this natural resource. Box 6: Influences of the physical environment. Climate: The warm sunny summers and mild, frost free winters of central southern England are critical factors in the ecology of many rare and scarce plants and animals found in the Natural Area. Geology, soils and drainage: The Natural Area contains a wide range of geology and drainage system resulting in a wide variety of soil types. These support many different habitats ranging from heathland and valley mire on acid soils to the calcareous fen habitats associated with marl clays. In the New Forest many of the soils have remained undisturbed for many centuries, allowing further soil types to develop within woodlands and in valley mires and seepages that are of nature conservation importance in their own right. Coastal features: Natural coastal features include estuaries, shingle spits and beaches, grazing marshes and their associated sea walls and low eroding cliffs. These features all support a characteristic range of plants and animals, many of great nature conservation importance. 18