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Home , A690 road, Bishop Middleham Quarry, Cassop, Cassop Vale, Castle Eden, Castle Eden Dene

MAGical meadows and the Durham Magnesian Limestone Marsden old quarry local nature reserve Preface

The is blessed with landscapes celebrated nationally and internationally for their beauty and biodiversity. Many are protected and enhanced, others, including Durham’s Magnesian Limestone areas, have been given relatively little protection and have been exploited with scant consideration as a result.

This book tells a story of a landscape of great rarity. It is also a story of crude exploitation of minerals, habitats and over many years, culminating in the great ecological and visual damage caused by coal mining, quarrying and waste disposal in former quarries.

It is a story about both the fragility and resilience of the area and tells how it has survived and is being restored following belated recognition of its unique importance. The Turning The Tide Millennium Project, which accelerated the recovery of the after more than a hundred years of colliery waste tipping on clifftops and beaches, is evidence of the scale of restoration required.

The purpose of this publication is to further increase awareness of the importance of this limestone landscape and show how it can be handed on to future generations in a state that reflects well on our stewardship.

David Miller

DURHAM

photo: www.wildstock.co.uk Contents Thrislington NNR Introduction

Introduction 01 The vast areas of limestone laid down beneath Caribbean-like shallow warm seas about 290 million years ago, in what is now northern Europe, have been the basis for prosperous agriculture and rich resources of wildlife and minerals. These lime-rich bedrocks provide fertile soils, which are home to widely diverse Geological History 02 habitats and species, abundant water in aquifers and quarried stone for building and chemical processes. Where limestone exists, settlements have thrived as local people have benefited from the exploitation of this rich resource. Social History 10 Limestone, however, is not a uniform material. It exists in many forms, depending on the fineness of its grains and its chemical content. The Magnesian Limestone of is one of the rarest and most valuable and the Current Status 14 coastal cliffs are unique in the British Isles, home to communities not seen together anywhere else in the country. Because as much as two thirds of the national resource of Magnesian Limestone grassland occurs in the North-East of and plant communities 18 , it is seen as the jewel in the crown of the region’s biodiversity. This has counted for little in the past and the crude exploitation of mammals, plants and minerals has diminished the area’s natural diversity. This book records Durham coastal cliffs 24 the loss of several species of mammal and many plant species. Agricultural practice, as is the case almost everywhere in the country, has been a major factor in further depredation. It is, however, the existence of the many limestone quarries on the escarpment, once so crucial to the steel and refractory industries Invertebrates 28 of the North-East, that has provided the refuge for threatened wildlife. Indeed, many of the best sites to explore the wildlife and geology of the area are old quarries.

Butterflies 30 A further threat to this fragile balance came from pressure to fill the quarries with household and industrial waste. Many have been filled and it is unknown what effect this will have long-term on the quality of water supplies taken from Mammals, amphibians and reptiles 36 the primary aquifer that underlies the area. Much of this threat has now been contained as regulations for new and extended quarries have become more tightly drawn.

Birds 40 The conservation of the area’s resources is a matter of considerable importance and there are yet more uncertainties in the face of climate change that could have a dramatic impact if temperatures rise according to current predictions. The Future 44 Nevertheless, for many years to come the Magnesian Limestone needs to be protected and its wildlife conserved. The recognition by local people of the importance of caring for their unique natural environment is crucial if their communities are to be truly sustainable. Ten Places to Visit 48

photo: www.wildstock.co.uk Carboniferous Rocks - Fig 2. Horizontal section through Durham Coalfield the world’s great deserts in which sand, Geology of the Durham formed by the wearing away of the hills, The Coal Measures accumulated as long belts of dunes. We see these today as the ‘Yellow Sands’, Magnesian Limestone Most of the coal worked in County that are extensively worked for building Durham occurs within a group of rocks sand in quarries around Quarrington, known to geologists as the Coal and (Fig 3). Evidence of Measures. The coal occurs as thin layers, their wind-borne origin may be seen in by Brian Young or seams, sandwiched between beds of the huge dune-bedding so clearly other rocks such as shale and visible in quarry faces, and in the sandstone. perfectly rounded ‘millet seed’ shape of individual grains. The sands continue at These rocks date back to the later part of the Carboniferous Period of earth history, roughly 316 to 295 million years by enormous rivers carrying sand and Coal Measures rocks lie beneath the Fig 3. Permian Yellow Sands, fossilised sand dunes, being worked for building sand at As the area described in this book ago. At this time, the area that was to silt from uplands in the area now Magnesian Limestone and crop out at Introduction Crime Rigg Quarry, Sherburn comprises the eastern part of the become Great Britain lay almost astride occupied by the Scottish Borders and the surface immediately west of the

The special landscape of the Durham YoungBrian Photo: Durham Coalfield, before looking more the equator. Vast, low-lying, forest- northern North Sea. The forests Magnesian Limestone escarpment Magnesian Limestone, with its closely at the Magnesian Limestone covered tropical swamps were crossed contained enormous primitive trees, (Fig 2). Apart from in the banks of the distinctive flora and fauna and itself, and in order to understand the including ancestors of the modern club- River Wear at , interesting social and economic history, coal mining industry that has mosses and conifers, together with and in an old quarry near , they reflects events and processes that been so important in shaping giant ferns and horsetails (Fig 1). True are rarely exposed in the area, but have shaped this area many millions of years the area, we need to look briefly flowering plants had not yet evolved. been worked in numerous collieries. ago. In order to properly appreciate the at these coal- bearing rocks. Animal life included huge newt-like The best places to see examples of the area as we see it today, we need to amphibians and giant dragonflies. Thick full range of Coal Measures rocks are understand something of the accumulations of peat and leaf litter on old colliery tips and on the beaches of fascinating story of the rocks the forest floor became compressed, the Durham coast, where large amounts beneath our feet. when buried beneath silt and sand, to of spoil were once dumped. form the coal seams we know today. Fossilised leaves and roots from these forests are commonly found in beds of Permian Rocks shale within the Coal Measures. Some The episode of earth history that fine specimens of large petrified logs of followed the Carboniferous is known as a tree known as Cordiaites were found the Permian Period. This lasted from several years ago in an opencast coal pit about 295 to 250 million years ago. It at Priors Close, near . was during this time that the Durham Magnesian Limestone was formed, Near the end of the Carboniferous although a few other events were to Period, as this part of the earth’s crust affect the area before the limestone Fig 1. Artist’s reconstruction shifted northwards, great earth itself was deposited. of the type of lush tropical movements squeezed and folded the forest in which the vegetation The landscape created at the end of that formed the area’s coal coal seams and other rocks, pushing Carboniferous times drifted further seams was deposited, about them up to form hills and mountains. 310 million years ago Weathering and erosion of this new northward to between 10 to 30 degrees landscape set the scene for the next north of the equator during Permian Painting: Elizabeth Pickett period of earth history. times. Northern Europe was then one of 2 3 Photo: Brian YoungBrian Photo: This desert landscape was eventually Above the Marl Slate occurs a rather YoungBrian Photo: Areas of land and sea during Permian times flooded as the waters of the Zechstein complex succession of limestones of Sea, a precursor of the modern North different compositions and textures, Sea, spread rapidly across the area, formed in rather varying conditions ZECHSTEIN SEA reaching as far as the present day beneath the waters of the Zechstein ROCKY HILLS eastern edge of the (Fig 4). Sea, and collectively termed the

PENNINE RIDGE County Durham Unlike the present-day North Sea, this Magnesian Limestone (Fig 7). Barrier Reef was a warm sea that dried up almost Whereas true limestone consists completely on several occasions. almost entirely of the mineral calcite (CaCO3), many of the limestones here The earliest limestone to be deposited, in east Durham contain large probably about 270 million years ago, amounts, or may consist almost was a thin bed of dark grey bituminous exclusively, of the magnesium-rich ROCKY HILLS shaly limestone, known in North-East mineral dolomite (CaMg(CO3)2). Such England as the Marl Slate (Fig 5). The Fig 5. The Marl Slate (the thinly-bedded grey rocks are often called dolomitic composition and fossil content of this rock above the hammer) resting on Yellow limestones or magnesian limestones. rock indicate its deposition in stagnant Sands. Old Quarrington Quarry, County Durham. It is important here to differentiate water, perhaps between 200 to 300 between the rock type ‘magnesian Fig 4. Extent of the Zechstein Sea metres deep. The Marl Slate is limestone’ and the formal geological internationally famous for its locally unit called the Magnesian Limestone depth beneath the limestone where, abundant fauna of beautifully Ferryhill and elsewhere. which, although including much because they are so porous and preserved fish, especially species of Quarry is famous for specimens of early magnesian limestone, also includes typically contain huge quantities of Palaeoniscus (Fig 6) together with rarer reptiles such as Protosaurus and other less magnesium-rich water, they presented major problems reptile, amphibian and plant fossils. Adelosaurus and Eppleton Quarry, near limestones. It is almost certainly this in sinking colliery shafts. Beneath parts Numerous magnificent specimens have Hetton-le-Hole, yielded one of only a abundance of magnesium that of the North Sea, these same sands, are been collected from quarries in the handful of European specimens of the accounts for the area’s characteristic important reservoirs for oil and gas. Sunderland area, at Quarrington, early gliding reptile Coelurosaurus. Magnesian Limestone flora.

Being rather more resistant to erosion than most of the underlying Coal Measures rocks, the Magnesian Limestone typically forms a prominent west-facing escarpment overlooking the central part of County Durham (Fig 8).

Fig 7 (top inset). Limestone typical of the Fig 6. Palaeoniscus longissimus - a fossilised lower part of the Magnesian Limestone, fish from the Marl Slate, collected at Chilton Quarry, Ferryhill. YoungBrian Photo: Thrislington, County Durham. Engraving from King W. 1850. Monograph of the Permian Fig 8 (right). The Magnesian Limestone Fossils of England. Palaeontographical Society Monograph escarpment overlooking the Coal Measures reproduced by courtesy of the Palaeontographical Society. outcrop, Houghton Cut, Sunderland

4 5 Photo: www.wildstock.co.ukPhoto: Fig 11 (top inset). Reef Limestone exposed YoungBrian Photo: at Humbledon Hill, Sunderland during the widening of the A690 road in the 1970s. Now unfortunately concealed beneath a retaining wall.

Fig 12 (bottom inset). Typical ‘Canon Ball’ Limestone exposed in Fulwell Quarries Sunderland.

Fig 13 (right). Star-shaped groups of calcite crystals in the Concretionary Limestone exposed at Marsden Old Quarry LNR.

original limestone, commonly consists of masses of spherical concretions which vary in size from a small pea to a small football. In places, the concretions occur as fan-shaped aggregates of narrow rods or as star-shaped groups of calcite crystals. Spectacular sections of this rock are exposed at Marsden Old Quarry LNR Fig 9. Vertical limestone cliffs and sea stacks near Marsden and on the coast at Hendon, south of Sunderland, with smaller exposures in On the coast, the Magnesian Limestone of hills extending from Downhill at West the sea cliffs near Crimdon. typically forms vertical cliffs, commonly Boldon, through Humbledon and with caves and sea stacks reflecting in Sunderland, to Beacon Many parts of the Magnesian Limestone differing degrees of resistance to Hill at Easington and Blackhall Rocks on have been worked as a local building erosion (Fig 9). the modern coastline. In places, a stone, but larger quarries continue to be variety of reef-forming animals are quarried to supply limestone and

The details of the Magnesian Limestone strikingly preserved, though in many dolomite to the construction and YoungBrian Photo: succession need not concern us here. places recrystallisation of the limestone chemical industries However, the lower beds of limestone, has destroyed or obscured these. exposed in numerous quarries and road Periodic evaporation of water in the cuttings on the escarpment, show clear Other distinctive limestones include the Zechstein Sea caused minerals dissolved roughly horizontal bedding. Although ‘Flexible Limestone’ exposed on the in the water to crystallise, forming thick fossils are generally scarce in most of coast north of Sunderland, so called beds of anhydrite (CaSO4), gypsum these rocks, a feature of the Durham because its very thin layers can often be (CaSO4.2H2O) and, more rarely rock salt Magnesian Limestone is the presence of bent like cardboard. The Sunderland (NaCl) and potash (KCl). These minerals a well-preserved barrier reef, formed area is also famous for the are collectively known as evaporites. close to the Zechstein coastline. Unlike ‘Concretionary Limestone’, often Anhydrite was formerly mined at most modern reefs, this was built not of Fig 10. Fenestella retiformis - a fossilised referred to locally as the ‘Cannon Ball and , for making corals, but of the skeletons of ‘moss-like bryozoan from the Magnesian Limestone reef, Limestone’ (Fig 12 ). This odd-looking cement and chemicals. Rock salt is still animals’ known as bryozoans, together collected at Humbledon Hill, Sunderland. rock, which is believed to have formed worked by pumping brine from Engraving from King W. 1850. Monograph of the Permian with a wealth of shells (Figs 10 & 11). Fossils of England. Palaeontographical Society Monograph by complex recrystallisation of the boreholes in the Hartlepool area, and The reef today forms a conspicuous line reproduced by courtesy of the Palaeontographical Society. potash is mined at Boulby, south of the Photo: www.wildstock.co.uk

6 7 area. Near the surface these soluble occasions, scouring the landscape and Fig 15. The ‘Raised Beach’ exposed in the cliffs from across the North Sea. A prominent 38000 year old shells, preserved about JOHNSON, G.A.L. 1970 (compiler). Geology of minerals normally dissolved millions of leaving great spreads of glacial debris in above Shippersea Bay, Easington belt of rather hummocky country 30 metres above the modern beach at Durham County. Transactions of the Natural years ago, causing the overlying their wake. Between long cold spells the YoungBrian Photo: between Easington and Hartlepool has Easington (Fig 15) and the submerged History Society of Northumberland, Durham limestone to collapse. The rubble-like climate became at least as mild as it is been interpreted as a morainic deposit forest of 8-9,000 year old tree trunks and , Vol. 41, No. 1. appearance of much of the limestone today, only to be followed by a return to that may have formed near the meeting about 15 metres below present sea JOHNSON, G.A.L. 1995 (editor). Robson’s exposed on the Durham coast is a result cold conditions. of two ice streams. Whereas boulder level near Hartlepool. geology of . Transactions of this process of ‘collapse brecciation’. clay covers large parts of the area, it is of the Natural History Society of Northumbria, Most widespread and conspicuous of most clearly seen as the brown stony The comparatively sudden release of Vol. 56, Part 5. From late Permian times until as the deposits formed at this period is till clay capping the limestone in the huge amounts of meltwater, combined recently as two million years ago, the or boulder clay. This comprises a coastal cliffs (Fig 14). A wide selection of with the gradual rise in the land, cut the MILLS, D.A.C. and HULL, J.H. 1976. Geology of story of this part of County Durham heterogeneous mixture of boulders, ‘erratic’ blocks can be collected from deep canyon-like gorges we see today the country around . Memoir of falls largely silent. sand and clay dumped by the ice these beaches. as the coastal denes. Other channels, the Geological Survey of Great Britain, Sheet 32 sheets. Boulders of distinctive rock cut by meltwaters, may be seen inland (England & Wales) types, known as ‘erratics’, reveal the Deposits of sand and gravel, and locally near (Fig 16) and at Ferryhill. Quaternary Geology direction of ice flow. Over much of east pockets of silt and clay deposited in SMITH, D.B. 1994. Geology of the country around Sunderland. Memoir of the British Roughly two million years ago, a Durham there is evidence of ice temporary lakes, also occur locally Geological Survey, Sheet 21 (England & Wales) worldwide episode of global cooling bringing rocks from the Cheviots, either resting upon, or inter-bedded, caused ice sheets more than one Pennines and Lake District although, with boulder clay. SMITH, D.B. 1995. Marine Permian of England. kilometre thick to extend southwards close to the coast, distinctive References Geological Conservation Review Series No. 8. across northern Europe on several Scandinavian rock types reveal ice flow Over time, the land surface became Because the Durham Magnesian Limestone Chapman & Hall, London depressed by the enormous weight of and adjoining areas have long been the ice. As this finally melted, about 11,000 subject of geological research, a very large SMITH, D.B. and FRANCIS, E.H. 1967. Geology Fig 14. Boulder Clay forming the upper grass-covered slopes above the Magnesian Limestone near Blackhall Rocks technical literature exists. In a publication of Photo: www.wildstock.co.uk years ago, the land rose. Combined with of the country between Durham and West the release of vast quantities of glacial this sort it is appropriate to list only a Hartlepool. Memoir of the Geological Survey of handful of the most important or most meltwater this resulted in fluctations in Great Britain, Sheet 27 (England & Wales) readily accessible of these texts. The reader sea level and repeatedly changed the interested in accessing more specialised position of the Durham coast. descriptions is directed to the very Distinctive deposits formed at this time substantial reference lists contained in the include the ‘raised beach’ containing publications listed below. Fig 16. Glacial meltwater cut channel near Kelloe Photo: www.wildstock.co.uk

8 9 farmsteads were built. This allowed The Social and farmers to concentrate on the type of farming best suited to a particular location. Once the coal industry began Economic Development to develop in east Durham, then its requirements, particularly fodder and summer grazing for pit ponies, led to of the Magnesian Seaton Holme, a medieval manor house in the specialisation of some farms. the agricultural settlement of Easington, c1950 The other group of settlements are (DCRO D/CL 5/1026) Limestone characterised by the more formalised terraces of nineteenth and twentieth found to have buildings which pre-date century housing and are the colliery the nineteenth century, with, usually, a villages of the east Durham plateau. In by David Butler medieval parish church. These much of County Durham, coal seams lie settlements came into existence as close to the surface and were relatively agricultural villages, and largely still retain easy to exploit. However, in the east of To understand the history of the area, working of the land was established, an agricultural base, although the map the county, the ‘concealed coalfield’, the an understanding of its geology and with large arable town-fields will also show evidence of agricultural seams are overlaid by the Magnesian ecology is also necessary. The often subdivided into unfenced strips which villages which have not survived, such as Limestone, and for many years there bleak and windswept Magnesian changed hands regularly and a Yoden, which had become deserted by were doubts that coal existed beneath Limestone plateau is geologically population largely living in clearly the sixteenth century. distinct from the area to the west, and defined settlements. the limestone. From the end of the Horden tipping point for colliery waste, near Warren House Point, c1950 (DCRO URA 133/5) although its social and economic In many cases the distinctive ridge-and- eighteenth century, however, it was A map of the Magnesian Limestone development broadly mirrored the furrow ploughing pattern, often cutting generally accepted that coal would be Colliery in 1822. With proof of the companies. With the demise of the coal plateau reveals a landscape of relatively remainder of the county, in the east across modern field boundaries, can be found although it was believed that it existence of good quality coal, collieries industry went the closure of the small settlements, falling into two broad developments occurred at different found near these settlements. The would be low grade and expensive to began to spread over the plateau. The railways, and all that now remains is the categories. On one hand there are those times and followed different routes, seventeenth century saw the dispersion obtain. general trend was eastwards and, in the coastal line, completed in 1905. The old with an irregular layout and central of the population with the change to a thus giving the area a uniqueness Eventually, declining production in the twentieth century, deep coastal pits railway routes have often survived as village greens, such as Easington, pattern of individually owned and which persists today. exposed coalfield and increasing were sunk which worked eight walk-ways or simply as undeveloped which, if studied on the ground, will be worked holdings on which isolated kilometres out under the North Sea. corridors and as such, provide refuges In prehistoric times, the plateau was demand for coal directed interest to east Durham, at a time when These pits represented the final phase for the unique flora and wildlife of the covered with a forest in which different Aerial photograph of the earthworks of Yoden deserted village at , 1968 (DCRO CC/X 172/44 no.428) of the coal industry in Durham, and the plateau, and reservoirs from which that types of trees predominated as technological developments provided solutions to the problems of ventilation county’s last colliery, Wearmouth, flora can begin to re-establish itself. conditions changed. Because the soils closed in 1993. were relatively dry and easy to work, and drainage and made it possible to There was no pool of labour available the clearance of the forest preceded work at greater depths. The capital Coal only becomes saleable if it can be locally to work in the growing coal other areas of the county and by Roman requirements for these new sinkings moved economically to its markets, and industry, and the need to house the times the plateau was probably an area were beyond the capacity of individual this meant cheap transport to the coast. immigrant mining families led to the of relatively intensive arable farming on landowners, and this led to the This was accomplished by railways with growth of the ubiquitous pit village, the better soils, with widespread establishment of joint-stock mining a mix of locomotive and rope haulage, with terraces of houses constructed by pastoral activity. Woodland would have companies with greater financial as used on the Hetton Colliery Railway, the colliery company, chapels, been mainly restricted to the steep resources. The first successful attempt the first railway in the world designed allotments and basic shops. The east slopes of the denes and to areas of to breach the Magnesian Limestone to be operated by steam locomotives. Durham pit villages tended to be larger heavier, wetter soils. capping came with the Hetton Coal The growing number of collieries meant than those in the west and more Company’s sinking of Hetton Lyons the development of a network of lines, systematically laid out, but since they By 1000 AD a pattern of communal mostly owned by individual colliery had no rationale for their existence

10 11 which, perversely, had the effect of protecting the Magnesian Limestone cliffs from erosion. One of the benefits of the cessation of deep mining has been the chance to restore the coast to its former state, and the Turning the Tide project has removed some of the spoil and the sea is dealing with much of the remainder. The project has also reclaimed the colliery sites and permitted the acquisition, for the benefit of the public, of areas of cliff top arable land, much of which had been meadow before the demands of World ‘Castle’, built in the mid-eighteenth century for Rowland Burdon the elder, 1886 (DCRO D/CL 5/491) War II for food production led to its Harbour, with the 3rd Marquis of Londonderry’s original dock of 1831 in the foreground, ploughing-up. It is now being returned anti-tank blocks which were erected to centuries; the areas which they c1950 (DCRO D/CL 5/1984) to pasture with regimes which encourage the re-establishment of the protect the area from invasion. preserved for their own enjoyment have survived and are reservoirs for the unique Magnesian Limestone flora. Coal is not the only extractive industry other than the colliery, the closure of additions to colliery villages. natural flora of the plateau. The Burdon Another legacy from World War II can which has flourished on the Magnesian the latter inevitably led to economic family purchased land at Castle Eden in The coastal collieries did not create pit be found in the surviving pill-boxes and Limestone plateau. The limestone itself problems. One response, which was 1758, including which heaps but dumped their waste at sea. was, and remains, a useful raw material suggested in Easington Rural District World War II pill-box at they landscaped and laid out with Until World War II the sea was able to www.wildstock.co.ukPhoto: and the surface of the plateau is Council’s 1946 publication, Farewell promenades (such as Miss Mary’s Walk) deal with this waste and an equilibrium dissected by large quarries. Much of the Squalor, was the creation of Peterlee, a which could be enjoyed from The was broadly achieved, but with limestone has been despatched to new town named after the Durham Castle. This ensured the preservation of increased output and mechanisation Teesside to be used in the iron and steel miners’ leader, to provide better the Dene and its unique collection of the balance could not be maintained, industry, as a flux in the furnaces and centralised social and cultural facilities habitats, but also provided an area and the result was 12 kilometres of the for furnace lining. It is also used for than could be achieved by piecemeal which was open to the public from coast devastated by colliery waste, constructional purposes (road stone, around 1850. The Andersons then the hardcore and aggregate), and in Pembertons occupied the Hawthorn chemical and pharmaceutical Estate, with Hawthorn Dene, from the manufacture. In the past, it has been 1830s and were responsible for some of used as a building material and also the woodland planting which still converted into slaked lime for The head gear and surface structures of Easington survives. Hawthorn Towers was agricultural use in limekilns. On a Colliery sunk in 1899 and closed in 1993 demolished in 1969, but its site can still (DCRO D/CL 5/1046) smaller scale, and less disruptive to the be appreciated. The influence of the landscape, the overlying glacial Londonderry family was more in what deposits have been worked for clay, they built than what they preserved. sand and gravel at a number of The 3rd marquis had grandiose plans www.wildstock.co.ukPhoto: locations. for his new town of Seaham, most of Major elements in the East Durham which did not materialise, but the town landscape owe their survival to the and harbour are his memorial, and the large landowners who acquired estates family remained major landowners in Quarrying operations at in the eighteenth and nineteenth the area until theThrislington second Quarry half of 2006 the (Right) twentieth century. 12 13 Within the North-East there are four in the central area around the National Current Status National Nature Reserves on the Nature Reserves at Thrislington Magnesian Limestone, and . It is at these Plantation, Cassop Vale, Castle Eden two sites, together with the nearby by Julie Stobbs Dene and the Durham Coast. Of these, Town Kelloe Bank SSSI, that the best all except Cassop are also designated as examples of primary Magnesian Special Areas of Conservation under the Limestone grassland occur, areas of European Union’s Habitats Directive. original agriculturally-unimproved Limestone areas tend to be of special broader belt covering eastern County herb-rich grassland on shallow Natural England has also designated 48 interest for wild plants and the Durham Durham and a significant part of Magnesian Limestone soils. Here the Sites of Special Scientific Interest (SSSIs), Magnesian Limestone Natural Area is no Sunderland and . conditions are most appropriate for a exception. Within Britain the solid which are in varying ownership but In excess of 90% of the Magnesian remarkable assemblage of plant geology of Magnesian Limestone have legal protection under the Wildlife Limestone is overlain by “drift” deposits species, many of which are highly underlies an area of about 1,200 square and Countryside Act 1981. Of the 307 from later periods of geological history. attractive when in flower during the kilometres. This extends in a narrow hectares of Magnesian Limestone The depth of the drift determines how summer months. band, no greater than eight kilometres grassland in the North-East, 279 far the Magnesian Limestone can wide, from Nottinghamshire up to hectares are protected in this way. At The assemblage seen at sites such as influence plants growing on the surface. Yorkshire, and where it reaches least 132 further sites are designated as Thrislington Plantation is particularly it fans out into a much As much as two thirds of the UK “second tier” Sites of Nature significant because it includes plants of resource of Magnesian Limestone Conservation Importance (SNCIs), an northern affinities, which tend to occur grassland occurs in North East England unusually high density. SNCIs normally on the older Carboniferous limestones and because of its internationally have some protection through the local of areas like the and recognised importance, it can be seen authority planning system. , growing with plants of as a “jewel in the crown” of the region’s southern origins, which are more biodiversity. A large number of Grasslands typical of the chalk and limestones of organisations with nature conservation southern England. The Magnesian Within the North-East, the grasslands of interests are working together to ensure Limestone can, therefore, be seen as greatest interest are scattered that the best sites are protected and something of an “ecological bridge” throughout the Magnesian Limestone that others are enhanced through between these two types of plant Natural Area with the better sites on the appropriate management. community. Examples of northern west-facing escarpment on the coast or species include Blue Moor Grass photo: www.wildstock.co.ukphoto: Herb-rich grassland at Hawthorn Dene

location of Magnesian Limestone in Britain Carpet of Rockrose Thrislington NNR photo: www.wildstock.co.uk 14 15 photo: www.wildstock.co.ukphoto: ( caerulea), Bird’s Eye Primrose (Primula farinosa) and Mountain Everlasting (Antennaria dioica) while some of the southern species growing near the northern limit of their distribution, include Upright Brome (Bromopsis erecta) and the rare and beautiful blue Perennial Flax (Linum perenne). The latter is one of the most striking components of Thrislington National Nature Reserve and was protected “in situ” from quarrying when other parts of the herb-rich grassland were only saved through a transplantation scheme in the 1980s. Rather more numerous than the primary grasslands are secondary grasslands, Town Kelloe Bank photo: www.wildstock.co.uk most of which owe their origins to the recolonisation of old quarry workings photo: www.wildstock.co.ukphoto: but which can also occur on habitats be essential to the maintenance of a baccata) is an interesting additional North-East, characterised by the such as roadside verges and former herb-rich sward. component at Castle Eden Dene. presence of Blue Moor Grass (Sesleria railway lines. Many have developed an The ground flora of the denes contains caerulea) (so called because of its interesting flora of species which Coastal Denes many species which are indicators of amazing blue sheen in the early flourish on the rudimentary soils and their ancient status and species normally csummer) and the delicate Small orchid displays can be spectacular. It is Within the coastal strip the east-west more common in the West, such as Scabious (Scabiosa columbaria). critical that appropriate management is aligned coastal denes support some of Hart’s Tongue fern, flourish in the humid Bearing in mind that geological features carried out to conserve them and arrest the most natural woodland in North dene bottoms. the process of natural succession. On East England. The denes were created such as the fossil reef and Cannon Ball both primary and secondary Magnesian by glacial meltwater at the end of the Uniqueness Limestones are also unique to the area, Limestone grassland, management last ice age and are steep-sided and the claim for its importance is certainly requirements such as scrub removal, relatively inaccessible. Typically, Ash Not only is Magnesian Limestone justified. Both Magnesian Limestone cutting and introduction of grazing can (Fraxinus excelsior) and Wych Elm (Ulmus grassland unique to Britain but one of its grassland and lowland Ash woodland have been identified as habitats Birds-eye primrose glabra) flourish while Yew (Taxus main plant communities is unique to the photo: www.wildstock.co.ukphoto: deserving of special conservation photo: www.wildstock.co.ukphoto:

photo: Ian Armstrong photo: measures in action plans produced for Small scabious the area of old County Durham. Given the special interest of the Magnesian Limestone grasslands, it is fair to say that the best of the grasslands, such as Thrislington, display a degree of interest that makes them “more than the sum of their parts”. Many local people, with due justification, consider it a Bird’s eye primrose Cassop Vale privilege to live in close proximity to Early purple orchid Hawthorn Dene these special habitats and to be involved 16 in their conservation. 17 photo: Keith Cunningham Keith photo: Large woodlands only survived at the of Parnassus, and Yellow Flag Iris. Blue moor grass Flora and Vegetation coast, where the rugged terrain of the Drier areas support Round-leaved denes made farming impractical. This is Wintergreen and Juniper. where most of the characteristic of the Magnesian woodland plants are still to be found. Characteristic flowers The coastal denes are the main habitat of the Magnesian Limestone for many of our native woodland plants, including trees such as Yew and Small- Limestone include leaved Lime, shrubs such as Spindle and by John Durkin Spurge Laurel, and flowers such as Lily Blue Moor Grass (Sesleria caerulea), is of the Valley, Bird’s Nest Orchid and the characteristic grass of the Magnesian Herb Paris. Limestone. It flowers and sets seed early in the season and is able to grow in very The character and history of the Wetlands thin soils that dry out later in the Magnesian Limestone has produced summer. It is able to colonise new sites, special grassland, woodland, wetlands The porous nature of the limestone so it is found both in original grasslands and coastal areas that support a range reduces the likelihood of ponds and and in man-made habitats such as of uncommon plants. marshes forming on its surface. Only roadside verges and disused quarries. It the presence of glacial boulder clay also grows on the Carboniferous Grasslands here and there creates a waterproof limestones of Upper . The liner for wetlands. Consequently, ponds Durham limestones support about one There are very few original areas of are very scarce on the limestone, and quarter of the British populations of Magnesian Limestone grassland most are in old clay pits. They often this nationally scare plant. remaining. Those that survive are some have a richer flora than ponds on the of the richest grasslands and are mostly coal measures. Particularly important Time and place to see it - April to protected within SSSIs. Secondary are “flushes”, which are grasslands on September at any of the inland nature Bee orchid grasslands are much more numerous, sloping banks, with calcareous water reserves. It is less frequent at the coast. and, although they lack some of the trickling downhill, the main habitats for Sea Spleenwort (Asplenium marinum), notable plants of the original Butterwort, Grass of Parnassus, Bird’s grows only in the sea spray zone on the

grasslands, they are often quite rich in Eye Primrose, and Lesser Clubmoss. Magnesian Limestone cliffs. It is an www.wildstock.co.ukphoto: other special species. Some of these evergreen fern related to the Hart’s secondary grasslands originate from Coast Tongue, adapted to grow in these land affected by quarrying, road difficult conditions. Its preferred habitat construction or other developments. The coast is a particularly interesting is rocks soaked with spray at every high Others are original grasslands that have habitat, contrasting with the inland tide, where even Thrift and Sea been ploughed for arable crops then limestone. It has a milder, wetter, more Mayweed cannot grow. It particularly allowed to revert to pasture. frost-free climate, and the limestone likes the harder limestone layers with photo: www.wildstock.co.ukphoto: habitats are less fragmented than pits and hollows, where young plants Woodlands inland. can establish themselves. The rapid The cliffs and headlands have a mixture erosion of our coastal cliffs in recent The first farmers cleared most of the of coastal and limestone species, years has resulted in the loss of some of Bridges John photo: woodland from the Magnesian including Sea Spleenwort, Dropwort the colonies of this fern, but its Limestone escarpment, leaving only and Thrift. Small flushes on the sea preference for harder rocks ensures that small woods on the steepest slopes. banks support Bird’s Eye Primrose, Grass some will survive. Perennial flax Northern marsh orchid 18 19 photo: John Bridges John photo: photo: www.wildstock.co.ukphoto: photo: www.wildstock.co.ukphoto: Time and place to see it - At any time of lowland sites. Bridges John photo: the year, in the bays north of the caves Time and place to see it - May and June at Blackhall Rocks, and on the north at Town Kelloe Bank, Thrislington and side of Shippersea Point. Blackhall Rocks. Perennial Flax (Linum perenne), is one Butterwort (Pinguicula vulgaris) grows of the rarest and most beautiful of the on very poor damp soils, even on almost flowers of the Magnesian Limestone. bare rock, because it supplements its The blue flowers are at their best at the Birds eye food supply by catching insects. Sticky same time as yellow Rockrose and Butterwort primrose Thrift glands on the leaves trap the insects, the purple Thyme, making a colourful soft parts of which are then dissolved display. It is easy to find when in flower and absorbed by the plant. The yellow- at its two remaining sites, as it usually green rosettes of leaves are distinctive. flowers prolifically. Occasional plants Butterwort can be found with white flowers. Time and place to see it - L.N.R, from May to July. Perennial Flax has declined from six sites in the 1960s, down to two now. Cowslip (Primula veris). Most of the

photo: www.wildstock.co.ukphoto: The other sites were lost due to the flowers of the Magnesian Limestone encroachment of gorse and hawthorn bloom in mid summer, but cowslips, scrub, and by burning of the scrub. common on all of the reserves, are one However, it is abundant in its two of the earliest spring flowers. They flower remaining sites, which are both at the same time as the Blue Moor Grass, protected as nature reserves. and, on some reserves, Early Purple Recently, it has begun to spread to Orchids. Cowslips are much more neighbouring sites. adaptable than their relative, the Bird’s Eye Primrose, and can commonly be Time and place to see it - In June and seen on roadside verges, especially July, at Harton Down Hill near South along the A19. The Cowslip is the Shields and at Thrislington. grassland relative of the woodland Birds Eye Primrose (Primula farinosa). Primrose. These two flowers can be Named for the bright yellow centre of found together on some reserves, such its rose-pink flowers, this small primrose as Cassop Vale, together with hybrids of has its main habitat on the limestone intermediate form and colours. hills of the north Pennines. Like many Time and place to see it - Any of the other plants of the northern limestone, Magnesian Limestone reserves, in April it also grows on the lowland Magnesian and May. Limestone. Here it prefers original grasslands, especially where there is Common Rockrose, (Helianthemum www.wildstock.co.ukphoto: some flushing of water in the soil. This is nummularium). The bright yellow flowers one of the scarcest of the Magnesian of this small perennial shrub can be seen Limestone habitats, and the one that in most of the reserves, in rough has declined the most in the twentieth grassland, disused quarries and scrub. It century. Birds Eye Primrose is now a is very important in Durham, because it scarce plant found in only a handful of is the foodplant of the caterpillar of the Cowslip Northern Brown Argus butterfly. Rockrose

20 21 photo: www.wildstock.co.ukphoto: www.wildstock.co.ukphotos: photo: Dave Mitchell Dave photo: photo: Dave Mitchell Dave photo: Common spotted Sheltered sites with large amounts of Burnet moth on orchid Rockrose provide the main remaining Greater knapweed habitats for this butterfly, so some reserves have managed to increase the amount of rockrose. Time and place to see it - Any of the Magnesian Limestone reserves, from late May through to September. Frog Hart’s tongue fern orchid Greater Knapweed (Centaurea photo: www.wildstock.co.uk scabiosa). One of the tallest and most striking of the summer flowers on the Magnesian Limestone, found in a mixture of habitats including roadside verges and quarries. The tall, purple-red flowers are often accompanied by the Northern marsh orchid blue-violet flowers of Field Scabious, (Knautia arvensis). Fragrant orchid photo: Michelle Appleby photo: Time and place to see it - Any of the nature reserves, from June to August. Hart’s Tongue (Phyllitis scolopendrium). with rocks and very little soil, so it is characteristics are to assist in This evergreen fern covers the ground well suited to growing in the disused pollination by insects. The numbers of in large areas of the coastal denes. It is quarries. It is not as showy as the more orchids that flower in any given year unusual for a fern in having an colourful orchids, at first sight, but it can vary enormously, from a few dozen undivided, strap-shaped frond, instead repays closer inspection. to many hundreds, depending upon the weather. of the finely divided fronds of the other Time and place to see it - From June to Dark red woodland ferns. Some of the Hawthorn August in the Time and place to see them - Any of the helleborine Dene plants have Y-shaped, forked reserves at Quarry Magnesian Limestone reserves that fronds. The spores are produced from and . include disused quarries or limestone photo: the “sori”, brown lines on the underside grasslands. Most orchids flower in June of the fronds. Orchids are very common on the and July. Magnesian Limestone, particularly in Time and place to see it - all year the disused quarries. Some of these round, close to the streams in the orchids, such as the Common Spotted coastal denes. and the Northern Marsh, are frequent in Dark Red Helleborine (Epipactis other habitats. Special to the limestone atrorubens). Of all the flowers of the are three less common species, the Magnesian Limestone, this orchid is Fragrant, Pyramidal, and Bee orchids. very special because most of its British These are very well named, Fragrant population is in Durham Wildlife Trust having a strong sweet scent, Pyramidal reserves. These populations are having a cone shaped flower, and Bee carefully monitored each year. The Dark Orchids having florets that are said to Red Helleborine prefers bare ground resemble bees. All of these Typical Magnesian Limestone meadow photo: www.wildstock.co.uk 22 23 all plant photos: Dave Mitchell (unless credited) (unless Mitchell Dave photos: plant all are exposed to the full might of the Spleenwort (Asplenium marinum). Buck’s horn plantain Sea plantain The Durham Coast North Sea and a highly specialised flora has developed in response to the harsh Sheltered coastline conditions. at Castle Eden Dene, Horden by Dave Mitchell Plants with thick fleshy leaves, In direct contrast to the previous site, resembling those of succulents, cling to much of the Durham sea cliffs are the cliffs where few others can survive. protected behind artificial raised photo: Dave Mitchell Dave photo: The leaves help to reduce water loss in Sea beaches formed after the dumping of the salty soils and are less vulnerable to spleenwort colliery wastes into the sea last century. wind damage. Most obvious are the

beautiful carpets of Sea Pink or ‘Thrift’ Mitchell Dave photo: (Armeria maritima), which derives its names from its colour and habitat and from the fact that it ‘thrives’ or remains green throughout the year. Unique sea cliff Another evergreen specialist is Common vegetation at Marsden Bay Scurvygrass (Cochlearia officinalis) which Common scurvygrass Thrift is not actually a grass but a small The Durham Coast is unique in terms of member of the cabbage family. It has a Britain’s flora and vegetation. high content of vitamin C and, before Sea cliffs protected behind Although it only covers a 30-kilometre the discovery of citrus fruits, was eaten foreshore wastes at the mouth of section of coastline from by sailors on long sea voyages to Castle Eden Dene, Horden to Crimdon, it supports one third of all prevent them developing scurvy, a

Magnesian Limestone grassland in this Mitchell Dave photo: country and is the only place where This helps to shelter the vegetation Magnesian Limestone rock creates from the direct effects of the sea and plants find further shelter in the coastal outcrops. The area is also Common rockrose Wild thyme Greater knapweed located on a divide between the numerous gills and denes that dissect photo: www.wildstock.co.uk photo: www.wildstock.co.uk warmer drier south of Britain and the the coastline. The largest and most cool, wet north. These factors have accessible of these is at the mouth of resulted in a unique and internationally- Castle Eden Dene. important assemblage of plants and Its sheltered conditions help support a habitats that can be readily observed as diverse and robust grassland described in the following sections. Exposed sea cliffs vegetation, including Black Knapweed at The Leas, (Centaurea nigra), Greater Knapweed Exposed sea cliffs South Shields (Centaurea scabiosa), Devil’s Bit at The Leas and Whitburn Scabious (Succisa pratensis) and Wild Thyme (Thymus polytrichus), all of which disease caused by vitamin C deficiency. Coastal Park, South Shields support diverse insect life. Of particular Other salt-tolerant specialists to be seen note are the patches of common Some of the most exposed sea cliffs here include Sea Plantain (Plantago Rockrose (Helianthemum nummularium) along the Durham Coast occur here. maritima), Buckshorn Plantain (Plantago that support important coastal colonies Battered by gale force winds and winter coronopus) and the locally rare fern Sea storms laden with salt spray, the cliffs of the Northern Brown Argus butterfly photo: www.wildstock.co.uk Sea stacks and limestone cliffs, Marsden bay photo: www.wildstock.co.uk 24 25 photo: Dave Mitchell Dave photo: all plant photos: Dave Mitchell Dave photos: plant all all plant photos: Dave Mitchell Dave photos: plant all (Aricia artaxerxes). Flowered Rush (Juncus subnodulosus), Sea rocket Fleabane (Pulicaria dysenterica), Hemp Occasional slippages on the slopes of Agrimony (Eupatorium cannabinum) and the dene and adjacent cliffs create Greater Horsetail (Equisetum telmateia). spaces into which smaller plants can Other species of interest include some of germinate and survive. These include the last surviving bushes of Juniper several species of orchids as well as tiny (Juniperus communis) in lowland north short-lived representatives of the east England as well as small populations gentian family such as Common of Brookweed (Samolus valerandi), Grass of Parnassus Centaury (Centaurium erythraea), Pyramidal orchid Bloody cranesbill normally associated with dune slacks. Autumn Gentian (Gentianella amarella) and Yellow-wort (Blackstonia perfoliata). Sea cliff hollow with rare vegetation, Blackhall Rocks Sand dunes Burnt Lyme grass In contrast, areas of cliff top adjacent to orchid the dene are characterised by more at Crimdon Dene acidic soils and support unusual coastal Leaved Wintergreen (Pyrola rotundifolia) This represents the southernmost point communities of Heather (Calluna and Common Butterwort (Pinguicula on the Durham Coast and the only place photo: Dave Mitchell Dave photo: vulgaris). The latter species is one of the Common centaury on this coast where extensive sand few British plants that can capture and dunes can be found. digest insects on its sticky leaves to On the beach in front of the dunes, a Heather provide extra nutrients in difficult Purple milk vetch growing conditions. Such plant small pink-flowered representative of the assemblages are now rare and give us cabbage family known as Sea Rocket an idea of what the early vegetation of (Cakile maritima) forms fragmented Britain must have been like after the ice patches, surviving on decayed fragments melted at the end of the last ice age. It of washed-up seaweeds. Its seeds can vulgaris) and associated vegetation. is living history. float around the coast in the sea and colonise sandy beaches like coconuts on Unusual seepage In contrast, where the soils are thicker tropical islands. Immediately behind and rich in nutrients, species usually these patches, an extensive system of Juniper flushes at Blackhall Rocks associated with fen habitats of southern mobile sand dunes has been built up by England occur here, including Blunt- several drought-tolerant grasses, The southernmost cliffs on the Durham particularly Marram (Ammophila Coast are characterised by peculiar

photo: Dave Mitchell Dave photo: arenaria) and Lyme Grass (Leymus Hawthorn Dene, one of the numerous armchair-shaped hollows, which receive arenarius). Further inland, these give way denes that dissect the coastline calcium-rich seepage waters where Fleabane to species-rich fixed dune vegetation glacial deposits meet the underlying where colourful plants such as Bloody Magnesian Limestone bedrock. At Cranesbill (Geranium sanguineum), Spiny Blackhall Rocks, a very unusual Restharrow (Ononis spinosa) and Lesser assemblage of plants can be seen. For Meadow Rue (Thalictrum minus) grow in example, where the soils are thin and profusion. Of particular interest are poor in nutrients, species usually plants of southern England, such as associated with harsh upland habitats Burnt Orchid (Orchis ustulata) and of the North-East occur, including Grass Pyramidal Orchid (Anacamptis of Parnassus (Parnassia palustris), Bird’s pyramidalis), which are at, or near, their Eye Primrose (Primula farinosa), Round- northern limit. They grow alongside the Dunes at Crimdon Dene photo: www.wildstock.co.uk photo: www.wildstock.co.uk rare Northern Purple Milk Vetch 26 (Astragalus danicus), which is near its 27 southern limit. photo: www.wildstock.co.ukphoto: photo: Tedphoto: Benton Terryphoto: Coult Shrill carder Blomer’s Rivulet named after Captain Glow worm with an increase in the species to be Invertebrates of bumblebee Blomer who discovered it. Originally found in the county. In recent years, the found only in Castle Eden Dene and Ruddy Darter, Brown Hawker and Four then the nearby Hesleden Dene, the Spotted Chaser have colonised the the Magnesian moth was thought to be unique to county, and species like the Black Darter Durham. Since then, it has been found and Southern Hawker have become sparingly in other parts of the country much more abundant. All of the above Limestone and has become extinct in Hesleden can now be found on ponds across the Dene; Castle Eden Dene however, Magnesian Limestone. remains a stronghold. by Terry Coult The Durham grasslands, coast and

Burnet moth Fletcher Charles photo: coastal denes have always been rich, sound of bumblebees, but again the happy, hunting grounds for sensitive specialists like the Great Yellow entomologists and as the grasslands Bumblebee and the Shrill Carder Bee The flower-rich grasslands of the Gatekeeper and Grayling butterflies hum with insect life in the summer it’s have disappeared from Durham, in line Durham Magnesian Limestone, along were 19th Century extinctions in easy to believe that all is well. Taking a with a national decline in bumblebees. with the coastal grasslands and denes, Durham, which are only now beginning closer look however, shows just how support a wealth of invertebrate life to make their way back into the county. The coast and the Magnesian much has been lost and how great the and are one of the most productive Another butterfly with changing Limestone grassland support the two task is to restore first the flower rich habitats in the whole of the county. fortunes, which can still be found on common grasshopper species, grasslands and the limestone However, looks can be deceptive some of the Magnesian Limestone Blomer’s rivulet Common Green and Field Grasshopper, woodlands, and then the invertebrates because, although the common grasslands and along the coast, is the as well as the much less common that depend on them. Mottled Grasshopper. The Common invertebrates still abound, subtle but Dingy Skipper. In the first half of the 20th The Magnesian Limestone has two Ground Hopper is very rare in the adverse changes in the environment Century, it was on the increase but today other important, but threatened, North-East but has in the past been have seen the long-term decline or loss it is under threat and colonies are endemic moths, the Least Minor and found on the Magnesian Limestone and of the specialists which are most becoming extinct across the county. the Chalk Carpet, both are day flying in Castle Eden Dene. The only cricket sensitive to change. and are rarely recorded. Common Rockrose is the food plant of record for Durham is for the Grey Bush Since it was first described in 1831, the the caterpillars of both the “Durham” Anyone searching for moths at night on Cricket from Castle Eden Dene in 1833. “Durham” or “Castle Eden” Argus Argus and the, brilliant metallic green the Magnesian Limestone grasslands As grassland diversity has declined, butterfly, now called the Northern day-flying moth the Cistus Forester. might find their way lit by the light of then so have the grasshoppers. Brown Argus, has been the most Historically recorded from Sherburn Hill the glowworm. Rarely found in Durham, On a more positive note, the famous insect in Durham. Castle Eden and along the Durham coast, the Cistus its distribution on the coast has dragonflies of Durham are doing well, Dene in the 19th century became the Forester is still occasionally found on the declined to only two known locations, hunting ground of many entomologists coastal grasslands. Related to the Cistus

Thrislington Plantation and Warren Dover Keith photo: seeking the “Durham Argus” and other Forester, but much more common and House Gill. Snails, the food of the butterflies, which once lived in and very easy to see, are the day-flying, Six glowworm, still abound on the around the dene. Collectors came for Spot and Narrow Bordered Five Spot, Magnesian Limestone but even the photo: Rob Petley Jones Petley Rob photo:

photo: www.wildstock.co.ukphoto: butterflies such as Silver Washed Burnet moths, the latter introduced to snails are in decline with losses of Least minor Fritillary, Marsh Fritillary, Small Blue, Durham at Blackhall from Scarborough specialist snails such as the Eccentric , Speckled Wood and in 1891 by John R. Robson of Hartlepool, Grass Snail, the Moss Chrysalis Snail and Ringlet, all of which were lost to a famous local entomologist. the Heath Snail. Durham more than a hundred years Castle Eden Dene was also a popular ago. The late 20th Century saw the On a summer’s day, the limestone resort for moth collectors. In 1832, a new return of the Speckled Wood and the grasslands are alive with the sight and UK moth was found there; Captain Cistus forester Field grasshopper Ringlet. Similarly, on the coast, the photo: www.wildstock.co.uk 28 29 photo: www.wildstock.co.ukphoto: photo: www.wildstock.co.ukphoto: photo: John Bridges John photo: Marbled white grass feeders are all ‘browns’ with their Comma Butterflies of distinctive eyespots, including the Meadow Brown, Ringlet, Small Heath and Wall. The Small Heath prefers fine- the Magnesian leaved grasses like the fescues whereas a sparse sward with bare ground is more important for the Wall. The Wall is Limestone a species in serious decline in southern England, but is still abundant here. by Sam Ellis and Dave Wainwright As well as the Northern Brown Argus,

three other species feed on the leaves Bridges John photo: Clouded yellow of flowers. Both the brightly coloured Common Blue and the unfortunately photo: www.wildstock.co.ukphoto: photo: John Bridges John photo: Meadow brown Only 59 butterfly species are regularly Foodplants for caterpillars and flowers named Dingy Skipper feed on Common recorded in the British Isles, many of for nectar are abundant. Sites on steep Bird’s-foot-trefoil, but the latter only which are confined to the warmer, slopes and those with some scrub also breeds in a short, sparse sward and is southern counties of England. County provide the shelter loved by butterflies. consequently scarcer. Also seen in small Durham only sees just over half the Only one species, the Northern Brown numbers is the beautiful Small Copper, British butterflies (32 since 1995), but Argus, a member of the blue family, is whose caterpillars feed on sorrels. Large Skipper nearly all these are encountered either restricted to this habitat in Durham photo: John Bridges John photo: regularly (20 species) or occasionally because the caterpillar foodplant, Green-veined white (8 species) in the Durham Magnesian Common Rockrose (Helianthemum Dingy skipper Limestone Natural Area. nummularium) is not found elsewhere. Flower-rich chalk and limestone Butterflies are what they eat, or at least grasslands produce the best habitat what their caterpillars eat! The wide for butterflies. The range of grasses present on Magnesian Magnesian Limestone Limestone grassland support different

grasslands of Durham butterflies, often in some abundance. Bridges John photo: are no exception. The golden Small and Large Skippers both prefer quite tall grassland where their respective foodplants, Yorkshire The other main groups present on the Fog and Cock’s-foot grow. The other flower-rich grasslands are the ‘whites’ and ‘vanessids’. The whites include photo: www.wildstock.co.ukphoto: Small copper Small, Large and Green-veined Whites and the aptly named Orange-tip. The vanessids include the familiar Red Admiral, Painted Lady, Small Tortoiseshell, Peacock and Comma, all of which you are just as likely to see nectaring on buddleias in the garden. These species are usually seen in small numbers, because their foodplants (e.g. Brassicas, nettles, thistles) are not Painted Lady Speckled wood photo: www.wildstock.co.uk 30 31 photo: www.wildstock.co.ukphoto: Common Blue Common Blue abundant in this habitat. several species have colonised or recolonised the region in recent (female) Some butterflies are only seen very decades, almost certainly due to a occasionally, including the two ‘yellows’, warming climate. These include the the Brimstone and the migrant Clouded Small Skipper and the returning Ringlet Yellow. The rare Dark Green Fritillary has and Comma in the late 1980s and been recorded only a few times and the 1990s, together with the Speckled Marbled White is found at just one site, Wood in the new millennium. Both the having been introduced as part of a Grayling and the Gatekeeper have been Gatekeeper scientific experiment on climate change seen again in the county and it is to test whether or not Durham was now photo: John Bridges photo: www.wildstock.co.uk possible they might become re- warm enough to support this butterfly. established. Unfortunately the other In contrast to the grasslands, limestone extinct species are declining nationally Northern brown argus photo: www.wildstock.co.uk woodlands support relatively few and their nearest localities are too far species. The occasional Holly Blue can away to have a realistic chance of be seen, but close inspection of canopy recolonisation. Conservation efforts are confused with female Common Blues, trees might reveal two of our more now focused on ensuring the habitats which have some blue at the base of of remaining scarce species like the the forewings but the Northern Brown

photo: www.wildstock.co.ukphoto: Northern Brown Argus and Dingy Argus is smaller and has a characteristic Orange Tip Skipper are not lost. silvery appearance when in flight caused by the reflection of light on the photo: www.wildstock.co.uk underwings. In Scotland the butterfly Northern Brown has a distinctive white spot in the centre of the forewing, a feature Argus butterfly normally absent or scarce in northern The Northern Brown Argus butterfly is England, although it is present in about one of only five resident British species 5% of individuals on the Durham coast. Holly blue with a northern distribution, with The butterfly flies in June, July and into populations in both Scotland and August, occurring on both inland and elusive butterflies, the Purple Hairstreak northern England. This butterfly is coastal sites. This is a sedentary on oaks and the White-letter Hairstreak restricted to four distinct areas in butterfly with most adults flying on elms. The latter is under threat from northern England, with the Durham together in clearly defined colonies. On Dutch Elm Disease, but happily breeds Magnesian Limestone Natural Area the the coast it can be recorded from north on suckering elms, making it a bit more south-eastern edge of its British range. of Seaham to north of Hartlepool, with visible to the lepidopterist! Until recent genetic studies clarified the 23 colonies. The 11 inland colonies are Butterflies are the fastest declining position, the northern England nearly all located on the western edge wildlife group in the country. In the populations were often referred to as a of the escarpment between High past, when woods were more open, separate subspecies, the Durham or and Bishop Middleham. More with bigger clearings and wider rides, Castle Eden Argus. than half the sites are small, supporting more species were recorded but as The Northern Brown Argus is a member less than 0.1ha of suitable habitat, photo: John Bridges John photo: woodland management changed in line of the ‘blue’ family, but unlike all but the where the populations are less than 100 with modern forestry practices butterfly closely related Brown Argus, neither the adults. Conversely, Thrislington NNR has numbers declined and some Durham male nor female has any blue on the over 10ha of habitat and supports a Small tortoiseshell species became extinct. Fortunately, upperwings. They are sometimes population of up to 2000 adults.

32 33 photo: www.wildstock.co.ukphoto: 4. Little Wood LNR. This site supports a large COMMON NAME SCIENTIFIC NAME STATUS With the exception of a single sand dune Dingy skipper site, the butterfly is restricted to Dingy Skipper colony and a small Northern Small Skipper Thymelicus sylvestris Poda Regularly recorded Magnesian Limestone grasslands in Brown Argus population is also present. Recent Durham. The common feature of all sites habitat creation works are likely to increase the Large Skipper Ochlodes sylvanus Esper Regularly recorded abundance of both in future years. is the presence of the caterpillar Dingy Skipper Erynnis tages L. Regularly recorded foodplant, Common Rockrose 5. Wingate Quarry LNR: Dingy Skipper numbers seem to be rising at this site, possibly in Clouded Yellow Colius croceus Geoffrey Occasional (Helianthemum nummularium) growing in a lightly grazed or ungrazed sward. response to increased Common Bird’s-foot- trefoil abundance. The Marbled White occurs Brimstone Gonepteryx rhamni L. Occasional The distinctive white eggs are laid on the here well to the north of its natural range, upper leaf surface and larger thicker Large White Pieris brassicae L. Regularly recorded which extends only to the Yorkshire Wolds. The leaves towards the shoot tip are butterfly was released as part of a scientific Small White Pieris rapae L. Regularly recorded preferred. Like other ‘blue’ butterflies, the experiment into the impact of climate change. caterpillars produce a sugary secretion Although a population has become Green-veined White Pieris napi L. Regularly recorded attractive to ants. Caterpillars are established, the Marbled White has not yet colonised other nearby sites. Orange-tip Anthocharis cardamines L. Regularly recorded protected by ants from attack or infection in exchange for the sweet 6. Blackhall Rocks: This site supports the largest Green Hairstreak Callophrys rubi L. Occasional secretion, though this has been area of Common Rock-rose on the coast centred on Blue House Gill and is therefore a Purple Hairstreak Neozephyrus quercus L. Occasional observed only infrequently. bask on bare ground or stones and is crucial if the butterfly’s future within key site for Northern Brown Argus. Dingy There have been eleven recorded White-letter Hairstreak Satyrium w-album Knoch Regularly recorded occasionally feeding on various flowers. the county is to be ensured. Skippers can be found wherever Common extinctions since the early 1980s, all but County Durham is an important region Bird’s-foot-trefoil grows, sometimes in Small Copper Lycaena phlaeas L. Regularly recorded one on small sites. Losses are usually for the butterfly. More than 80 inland TEN BEST BUTTERFLY SITES high numbers. attributable to either overgrazing or Northern Brown Argus Plebeius artaxerxes Fabricius Regularly recorded sites support it and it is also 1. Thrislington Plantation NNR: This site 7. Castle Eden Dene NNR: The Northern Brown agricultural abandonment leading to widespread along the coast between supports one of the largest Northern Brown Argus was first described from the Castle Eden Common Blue Polyommatus icarus Rott. Regularly recorded scrub invasion. During the 1990s Hartlepool and Seaham. Argus populations in northern England. The Dene coast, hence the early name of Castle conservation effort focussed on scrub population has steadily increased since 1990. Eden Argus. Two coastal colonies are still Holly Blue Celastrina argiolus L. Occasional removal and the introduction of light The butterfly requires a combination Several large exclosures, where grazing is present, but the small population at the grazing regimes appears to have halted of bare ground interspersed with taller light, help maintain suitable habitat for the western end of the dene became extinct again Red Admiral Vanessa atalanta L. Regularly recorded the decline. At the landscape scale, it is vegetation. The main caterpillar butterfly. Dingy Skippers are present in the late 1990s despite a reintroduction attempt. Dingy Skippers occur here in good Painted Lady Cynthia cardui L. Regularly recorded no coincidence that all extinctions have foodplant is Common Bird’s-foot-trefoil, although rarely in high numbers and White- numbers and White-letter Hairstreak butterflies occurred on inland sites which are more although Greater Bird’s-foot-trefoil and letter Hairstreak can also be found here breeding on elm trees. can also be found breeding on elm trees. Small Tortoiseshell Aglais urticae L. Regularly recorded fragmented and isolated than coastal Horseshoe Vetch are occasionally used. 8. Warren House Gill: Another good coastal site Peacock Inachis io L. Regularly recorded colonies, making recolonisation much These requirements restrict the 2. . This site less likely. The effect of climate change is butterfly to two main habitat types supports large populations of both Northern supporting populations of both Northern Comma Polygonia c-album L. Regularly recorded within County Durham: brownfield Brown Argus and Dingy Skipper. The warm Brown Argus and Dingy Skipper. Suitable an unknown quantity but it may be that habitat occurs in both the gill and on t e sites and Magnesian Limestone microclimate means the quarry usually has Dark Green Fritillary Argynnis aglaja L. Occasional global warming may make some the earliest records of the year. The seaward cliffs. grassland. The number of inland Durham sites unsuitable for this species. vegetation grows slowly on the thin soil so 9. Tunstall Hills LNR. Dingy Skippers are present Speckled Wood Pararge aegeria L. Occasional colonies has declined by around a the habitat remains good for butterflies for in fairly good numbers. Main colonies are third since 1990 and most of these many years. Wall Lasiommata megera L. Regularly recorded losses have arisen through located within the disused quarry and around The Dingy Skipper Maiden Paps. redevelopment of brownfield sites, 3. Cassop Vale NNR. A small Northern Brown Marbled White Melanargia galathea L. Occasional Argus population occurs here and Dingy The Dingy Skipper is a drab grey and 10. Marsden Old Quarry. Dingy Skippers have with few if any of the colonies on Skippers are occasionally reported, usually in not been seen at this site as yet, although Meadow Brown Maniola jurtina L. Regularly recorded brown butterfly that looks very much Magnesian Limestone grassland having ones or twos. Light grazing by cattle and recent habitat creation work by South Tyneside like a moth. It is on the wing during May gone extinct. Continued protection and sheep help maintain suitable conditions for Ringlet Aphantopus hyperantus L. Regularly recorded Council has improved habitat condition and and June and is often seen making rapid enhancement of this important habitat the butterflies. the butterfly is likely to colonise in due course. Small Heath Coenonympha pamphilus L. Regularly recorded flights close to the ground, preferring to 35 carnivore the Otter seems to have Wild boar Badger Mammals, Reptiles and survived the depredations of the gamekeeper, hanging on in the county until almost completely disappearing Amphibians of the Durham during the England otter population crash of the 1950s and 60s, which was caused by pesticide pollution in rivers Magnesian Limestone and streams.

Today, the Otter is recolonising the by Terry Coult rivers and streams of County Durham, even as far as the and into the urban conurbations of Polecat Stockton and Middlesborough. Whether photo: www.wildstock.co.uk it ever permanently occupies the denes and coast of east Durham remains to be Wild cat Mammals east of Durham, mainly due to seen, but there have been a handful of All photos www.wildstock.co.uk deforestation, but lingered in very small recent tenuous otter records on the The dramatic changes undergone by numbers in the west of the county and Durham coast. the area’s mammals was illustrated by on the Northumberland border. Today, an incident in 1878. Quarrymen it has spread back to its former haunts, The most ubiquitous large carnivore of working the limestone of the Cleadon recolonising the larger coastal denes them all, the Fox, made it all the way Hills, near Whitburn Lizards, uncovered during the 1960s. through despite intensive persecution, a cave in which were found human the reason almost certainly being that bones along with numerous gnawed By the end of the 19th Century, the after the crash in deer numbers it was bones of native mammals and birds, unrelenting massacre of carnivores by promoted to a beast of the chase and including the remains of the now gamekeepers caused the demise in was preserved on some sporting extinct flightless seabird the Great Auk. Durham of the Pine Marten, the Wild estates so that it could be pursued by Wild mammal bones found in the cave Cat, and Polecat, one of the last of hounds, a paradox of the hunting were Wild Boar, Red and Roe deer, Fox, which was reported by the Rev. G. C. psyche. The smaller carnivores Stoat and Badger, Pine Marten, Weasel, Hedgehog, Abbes, of Cleadon, in his garden. The Weasel are still present across the whole Mole and abundant Water Vole bones; Wild Cat became confined to the far of the county. no doubt the remains of various north and west of Scotland and the carnivorous feasts. By the time the cave Polecat to Wales. Water Vole bones were found by the was quarried in 1878, the Wild Boar was quarrymen in 1878 as well, which may extinct in Britain, the Pine Marten In 1895, Sir Alfred Pease, the badger- have much to do with the local confined to the wilds of Scotland and digging MP for Cleveland, wrote that geography. The River Don flows into the the Badger, Red and Roe deer almost the Badger was extinct in Durham. Tyne at Jarrow and its extensive extinct in the North-East. Whether this was true is uncertain, but tributary system drains the flatlands of it was certainly the nadir in the fortunes South Tyneside, bordered to the east by Red deer became extinct in the wild in of the Badger in Durham; since that the Magnesian Limestone escarpment Durham, probably, during the 17th date the Badger has expanded in both at Cleadon Hills. It is quite likely that the Century and now exist in the county numbers and range and can once again Water Vole bones found in the Whitburn only in a private park. By the early 18th be found in the woods and denes of the cave were the remains of meals caught Pine marten Century, the Roe was gone from the east of the county. That other large by predators in the streams and ditches photo www.wildstock.co.uk 36 Water vole 37 which feed the Don. Once common Like the Grey Squirrel, many mammals UK mainland, including the rivers and www.wildstock.co.ukphotos All Weasel Grey seal on all streams and rivers in the North- found in Durham are aliens, which streams of east Durham. The first East, the Water Vole has suffered a arrived by hitching a lift on ships or reports appeared on the River Wear massive population crash across the were deliberately introduced. The in 1977. UK and is threatened with national Brown Rat reached the UK in the 18th extinction. The Don and its tributaries Century, eventually displacing the The immediate future is likely to however, still remain a home to the Black or Ship Rat, which had been here herald another change in the form Water Vole, but for how long? much longer. Mostly associated with of Chinese Muntjac, a tiny deer the coast, the Black Rat disappeared introduced into southern Britain Otter All photos www.wildstock.co.uk Of the smaller mammals, the Bank from North-East ports during the latter which have recently spread north and Field Vole along with the half of the 20th Century. For example, across the Tees and are colonising Woodmouse are ubiquitous across six Black Rats were killed on ships in parts of Durham. Stoat Field vole the region but the Harvest Mouse is Hartlepool docks in 1965, whereas in rarely recorded. The only Magnesian 1928 the number was 1,771. No doubt Amphibians Limestone record is a possible from black rats continue to occasionally Hawthorn Dene in 1975. Distribution arrive on board ship but are unable to and reptiles of the shrews is not well known, colonise our ports and harbours. The although it is likely that Common and Brown Rat is now widespread and The Tyne to Tees coast has no Pygmy Shrew are ubiquitous. Water common in Durham. Similarly the credible recent records of snakes but Shrew has been recorded from ubiquitous House Mouse is an alien, the legless, snake-like lizard the Bank vole Hawthorn Dene and a few other dependent on man to transport it Slowworm is occasionally recorded scattered localities across the county. around the world. from the coastal denes. The Common The other insectivores the Hedgehog Lizard has been recorded along the and Mole remain widespread in It is thought that the Normans coast, including most of the denes, the county. introduced Fallow Deer and Rabbits to Blackhall Rocks and Hart Warren. the UK as food; the latter were kept in Common Frog, Common Toad, Bat records for east Durham include, specially constructed enclosures called Smooth, Palmate and Great Crested Brown hare Noctule, Pipistrelle, Brown Long Eared warrens, the word often appearing in Newt are all present in ponds on the and Daubenton’s. place names, as at Hart Warren. In the Magnesian Limestone. The Palmate 19th Century, there were a number of Newt however, is very scarce, being Common Seals still breed on Seal deer parks around the county, more a N ewt of the western uplands. Sands at Teesmouth and both they including one at Wynyard with Fallow and Grey Seals can be seen off the Deer. Today, Fallow Deer are only coast and in the river estuaries. found in two parks in central Durham. Similarly the brown hare, which Great crested newt The most recent native mammal to be displaced the native Mountain Hare lost from the east of Durham is the over most of the UK, was introduced, Red Squirrel, still present in a few possibly in the Iron Age for food and places across the county including for sport. some of the coastal denes. Up to the turn of the 21st Century, the red The most recent coloniser is the squirrel had been almost completely American Mink; escaping from fur replaced in Durham by the introduced farms during the mid 20th Century the American grey squirrel, which is now Mink had now colonised most of the Roe deer Fox widespread in the county. Common toad Slowworm

38 39 All photos: www.wildstock.co.ukphotos: All The Birds of the Durham Heron Magnesian Limestone by John Olley

When it comes to birdlife, the area That birds have survived and thrived on supports one of the richest diversity of the coast is down, in part, to the species in Britain. The reason is that it dramatic improvements in habitats over offers many habitats, everything from recent years. For years, the Durham the open sea, cliffs, coastal grassland coast was blighted by coal spoil closely and you will see Cormorant, and denes to inland farmland, deposits but today, after the success of Fulmar, Kittiwake, Gulls, Jackdaws and woodland, hedgerows, wetlands and the Turning the Tide clean-up project, a Rock Pipit. valley streams. Some of Britain’s most huge change is occurring, making it Also good for birds are the coastal Bullfinch important species are to be found more attractive to birds. One of the grassland, scrub and farmland areas, across the area. But even though some features is the return, coming in from supporting large populations of Skylark, are scarce, whatever time of year you the open sea during winter and spring, Meadow Pipit, Reed Bunting, wander this area there is always of large populations of Common Scoter, Yellowhammer, Stonechat and Short something of interest to see. Red Breasted Merganser, Eider, Eared Owls, which abound over the cliff Red Throated Diver and various terns. and scrub interface. There is always a chance of a rarity over the sea, including Black Throated, Great Northern Divers, Storm Petrel and Leaches Storm Petrel, Shearwaters, Gannet, Long Tailed Duck and Skuas. Patience is certainly well rewarded on the Durham coast. The cleaned-up shoreline and beaches are also busy with waders scurrying for food and setting up nesting territories, including Oystercatcher and Ringed Plover, which now regularly breed, and Redshank, Knot, Sanderling and Turnstone all returning for the autumn and wintering in increasing numbers. Limestone cliffs form prominent features along the coast and provide nesting and foraging areas at all times of the year for a variety of species. Look Greater-spotted woodpecker All photos: www.wildstock.co.uk 40 41 All photos (unless credited): www.wildstock.co.ukcredited): (unless photos All Dunn Richard Photo: Merlin www.wildstock.co.ukcredited): (unless photos All farmed areas, we see a change; here the main land use emphasis is on food production so farmland birds tend to dominate. Important populations of species such as Grey and Red legged Partridges, Corn Bunting and Tree Sparrow are found here. Some areas still hold small populations of Lapwing and Curlew and important wetland sites Bee-eaters Nuthatch are to found at Bishop Middleham and Hurworth Burn reservoir with smaller Chaffinch and Goldfinch being ponds near Village. The Bishop Middleham complex has developed Yellowhammer common. Also adding colour are Blue, Great, Willow and Marsh tits. Warblers through minewater subsidence and such as Common Whitethroat , these wetlands are of local significance, supporting large flocks of wildfowl Willow warbler Blackcap, Chiffchaff and Willow Warbler all have high populations. including Wigeon, Teal, Shoveler, Gadwall and Mallard in their hundreds. The Green and Greater Spotted And waders such as Golden Plover, Woodpecker are very much at home Lapwing and Redshank can be here with the acrobatic Nuthatch and impressive as well. Treecreeper in the more mature sites. Breeding populations of birds in the Also, Buzzards are becoming a regular Photo: Allan Jones Waxwing Photo: Allan Jones area are high with Yellow Wagtail, species over the denes with Merlin in Little Ringed Plover and grebes doing the winter and Sparrowhawk and well. Old and working quarries provide Kestrel regularly breeding. refuges for Sand Martins, the declining Tree Pipit, Yellowhammer Sparrowhawk The coastal area is also very and continental breeding grounds. As we move inland to the more open important in providing a refuge and various warblers. Because the coastal denes are valuable for global travellers and sometimes remnants of once-larger blocks of In 2002, though, a very different visitor you can see large movements of woodland, they are very important for arrived in the form of a pair of Bee- common and rare passage birds in common woodland birds such as the Eaters, which were well off their normal spring and autumn. Among species finches and titmice. Bullfinches are breeding area and took up residence at which can gather in large numbers are found in scrubby areas with Greenfinch, Redwings, Fieldfares, finches and Grey partridge geese, moving inland during the autumn. You can also enjoy the sight of Great Grey Shrike, Icterine, Barred, and the tiny Pallas's and Yellow Browed Warblers. Birds of prey do not miss out either and Honey Buzzard, Hen Harrier and Montagues Harriers are rare spring visitors as they return to their upland Tree sparrow Lapwing Kestrel Bishop Middleham Quarry, the first UK 42 breeding for more than 50 years. 43 In many cases a reduction in make up the traditional and highly Mitchell IDave photo: the consistently warmer temperatures Juniper The Future biodiversity (the overall wildlife, both attractive Magnesian Limestone now predicted. plant and animal that the area grasslands. Old accounts show that In contrast, some species of southern supports) can be linked to what nature many areas that are now un-grazed, affinity may now be becoming more conservationists would call such as the grasslands along the by Julie Stobbs and Michelle Appleby widespread in their distribution. This inappropriate management. Durham Coast, were in the past certainly seems to be the case for Applications of fertiliser, over-grazing, grazed, and formerly supported more Upright Brome which is becoming more

photo: www.wildstock.co.ukphoto: or equally, neglect and an absence of diverse and abundant plant and common and is even somewhat of a This publication describes the unique grazing can dramatically change the invertebrate communities. intensively problem at several Magnesian nature of Durham's Magnesian managed farm wildlife value of grasslands but, as the All is not lost, however. In recent years Limestone grassland sites including Limestone, charting its history from the landscape agricultural sector has historically there has been a significant shift in geological legacy of the Zechstein Sea adapted to changing markets and New conflicts can still occur, of course. agricultural subsidies with the emphasis to the effects of human influences on government policies, the intrinsic value New quarrying, development of moving from maximising production to Southern hawker the landscape and the wildlife it of wildlife has rarely been top of the previously-used land, "brownfield" in sustainable management of land. This supports. The effects have included farm agenda. developers’ language, and the growth new approach is a direct recognition of harvesting crops from the surface of the in recreational use of the countryside An absence of grazing can soon lead to the biodiversity value of our landscape, ground and exploiting the mineral all bring their unique and sometimes encroachment with coarse grass species and the importance of the Magnesian wealth below. Despite this long history cumulative pressures. Brownfield and the development of scrub, both of Limestone grassland to the overall of use of the resource, there remains a development is the Government's which out-compete the more delicate biodiversity of the UK. Agri- unique historic and wildlife legacy that fertilisers and herbicides have all had a attempt to take pressure away from grasses and broad-leaved species which environment schemes administered by can be found nowhere else in the UK. negative impact on the grasslands and greenfield sites but, where brownfield wildlife of the Magnesian Limestone. Natural England specifically target From the second half of the 20th has lain undisturbed for many years, it Century onwards concern for the often has more value for wildlife than photo: Ian Armstrong photo: natural environment and its Ian Armstrong photo: the surrounding intensively Hebridean sheep at Crow Trees farmed landscape. conservation has grown apace and, as Local Nature Reserve public awareness of the natural Although many sites now enjoy nature environment has increased, it might be conservation designations, as explained assumed that the worst is over and that in the chapter on “Current Status”, there there is cause for optimism. The 21st is nevertheless always a threat from Century brings its own new threats, road construction, housing and other however. built developments and the need for Like many other habitats that are targeted and effective nature important in nature conservation terms, conservation continues. Magnesian Limestone grassland now Increasingly now, the native flora and has a highly fragmented distribution. Magnesian Limestone grasslands, fauna of Magnesian Limestone This isolation makes it vulnerable to making funding available to manage grassland can be affected by warming Thrislington National Nature Reserve. many pressures that can lead to its sites appropriately for their climate. This is particularly significant There are similar parallels with piecemeal loss. Over the past two conservation value. The opportunity for some of the ‘northern’ elements of invertebrate species; for instance hundred years the most significant now exists to re-introduce grazing on these unique communities like bird’s dragonflies such as the Southern amongst these threats has been areas like the Durham coast, using eye primrose, grass of Parnassus and Hawker have been extending their agricultural intensification. Ploughing traditional breeds such as belted juniper, which were hitherto more ranges northwards for several years, and reseeding of unimproved Galloway cattle and Hebridean sheep, widespread on the Magnesian now that warmer summers are grassland, conversion of pasture to which are suited to less intensive becoming the norm. Highland cattle are sometimes used for conservation grazing Limestone, particularly on the coast, arable land and increased use of agricultural practices. but are less likely to be able to tolerate

44 45 photo: www.wildstock.co.ukphoto: www.wildstock.co.ukphoto: photo: Dave Mitchell Dave photo: conserved, formerly important sites can been produced; Common Blue (male) Grass of Parnassus either be restored or enhanced and, l the Durham Biodiversity Partnership, perhaps most importantly, through which has identified a variety of targets appropriate spatial planning, and implemented actions for key important habitats can be linked. species and habitats within the Durham Perhaps in the future land use planners, area including Magnesian Limestone rather than nature conservationists, will Grassland; have the greatest role to play in conserving the unique character of the l the Durham Heritage Coast Magnesian Limestone areas of County Partnership, which has continued much Hoary Durham. Combining “habitat creation”, of the good work originally set up by plantain Global warming poses many questions which is used to develop new habitats the Millennium Commission-funded for nature conservation. If the in suitable areas, with the concept of “Turning the Tide” project; environment is changing to such an “connectivity” may well be the tool l the Grazing Animals Project, which extent that the plants and animals that which allows these two groups to work works to promote links between land once thrived are no longer able to together. A modern and integrated owners and managers with the owners tolerate the warmth, then what can be approach to land management relies of grazing animals to ensure that done and is it our place to attempt it? greatly on a strategy that will often grazing regimes are developed which Perhaps nature should be left to take its allow plants and animals to move are most advantageous for nature course, but can it really do so in a through the landscape. conservation. landscape so markedly changed by As humankind seeks to adapt to human activities? How can the plants There is now a growing awareness of

changing environmental conditions Mitchell Dave photo: and animals of fragmented habitats the importance and interest of the it is vital that we continue to record our move through a landscape where the North East’s Magnesian Limestone native flora and fauna and to monitor distance to a suitable site for occupancy grassland, promoted in part through any changes in their relative abundance can be many kilometres? Recent the interpretative and educational work which may be taking place. In order for conservation initiatives are increasingly carried out by organisations such as this work to be undertaken properly by looking to landscape-scale projects Natural England, Durham Wildlife Trust trained individuals it is essential that which allow these movements to take and the various local authorities. It is the necessary funding is found for place by creating habitat links. hoped that this publication will go surveys, monitoring and research, some way to further raising the profile which will inform future land Protecting and of this habitat type. photo: Dave Mitchell - management decisions. Frog Enhancing the Resource Predicting the future is impossible but, orchid On a positive note, it is appropriate to with good planning and the will to With the appropriate will, knowledge highlight the work of some of the many

grasp new opportunities when they www.wildstock.co.ukphoto: and resources, important sites can be excellent partnerships that are doing so arise, it will be possible to harness the Silver-y moth much to ensure that the unique interest energy of all sectors of the community of the Magnesian Limestone Natural to achieve a common conservation aim. Area is appropriately conserved and Working with groups such as planners, managed. Notable amongst these are: www.wildstock.co.ukphoto: farmers, quarry companies, highway l the MAGical Meadows Project lead officers, schools and colleges, together by Durham Wildlife Trust, funded by the with local interest and community MAGical Meadows Aggregates Levy Sustainability Fund, groups, many opportunities will exist to survey work under whose auspices this booklet has help benefit the biodiversity interest of Upright brome this important habitat. Striving to Rockrose on limestone 46 achieve our conservation goals requires 47 a flexible, pragmatic and often

Ten Places to Visit www.wildstock.co.ukphoto:

Publicly accessible places to visit and get to know the Magnesian Limestone flora and fauna are well distributed between the Tyne and the Tees. Below are ten sites where access on foot is unrestricted and it is possible to learn about and enjoy the unique habitats and species of the Magnesian Limestone as well as important geological features. Thrislington

Thrislington The site has been rated the UK’s best Least Minor Moth, and Glow-worm. Managed by Natural England full details of example of Magnesian Limestone the site can be found on the NE website. Location map showing ten sites that you can visit Plantation grassland and further designated as a Location National Nature Reserve Special Area of Conservation. Visit the Entrance to the reserve is via a public site between May and August to see the footpath leading off the minor road Wingate Quarry Description Magnesian Limestone grassland in full between West and Ferryhill Local Nature Reserve Thrislington Plantation supports the bloom. Thrislington supports the full Station. Parking is in the lay by adjacent largest stand of primary Magnesian range of Magnesian Limestone to the reserve sign, one mile south of Description Limestone grassland in Britain, having grassland species and the nationally West Cornforth and opposite the A limestone quarry abandoned in the survived attempted afforestation in scarce plants Perennial Flax, Blue Moor- Thrislington works, at grid reference 1930s, the site is now important for its Victorian times, scrub encroachment Grass and Dark Red Helleborine. NZ309325. exposures of limestone, secondary after grazing animals were removed limestone grassland, neutral grasslands from the site in the 1950s and a The site also has a wealth of General Information with associated flora along with scrub, proposed quarry extension in invertebrates including Northern Brown Grid Ref: NZ316325 woodland and wetland. Invertebrates the1980s. Argus Butterfly, Dingy Skipper Butterfly, OS Explorer Map No. 305 include marbled white butterfly and chalk carpet moth.

photo: www.wildstock.co.ukphoto: Location Off the B1278 minor road between Old Thornley and Trimdon Colliery, parking is at the reserve entrance.

General Information Grid Ref: NZ371374 OS Explorer map no. 305

Managed by Durham County Council. Full details of the site are available from DCC and from the DCC website.

48 Wingate Quarry 49 the DWT website. Blackhall Rocks

photo: www.wildstock.co.ukphoto: National Nature Reserve, Durham Wildlife Trust Nature Reserve

Description A natural exposure of reef limestone, Marsden Old Quarry topped by boulder clay with a total cliff height of 60 feet, the southern end of

photo: www.wildstock.co.ukphoto: the site has the largest caves on the extensive areas of Common OS Explorer Map No. 305 Durham coast. Marsden Old Quarry Rockrose, the latter being the food Local Nature Reserve Bishop Middleham plant of the caterpillar of the Managed by Durham Wildlife Trust. The cliffs support an internationally Northern Brown Argus butterfly Details of the site can be found on

Quarry www.wildstock.co.ukphoto: unique grassland community with a Description which can also be found in the very rich flora including Quaking Grass, A small site with excellent exposures of Durham Wildlife Trust quarry. Bishop Middleham Quarry concretionary limestone and a range of Nature Reserve Common Rockrose, Salad Burnet and Bloody Cranesbill. The wet gullies limestone grassland types including The site is best seen between April contain rare plants such as Butterwort, areas dominated by blue moor grass. Description and July for the orchids, June and Round Leaved Wintergreen, Grass of Small scabious, common rockrose, carline A limestone quarry abandoned in the July for Northern Brown Argus Parnassus, Brookweed and Birds Eye thistle, fairy flax and autumn gentian are 1930s and since that time colonised by a butterfly and July, for Dark Red Primrose. The locally rare fern Sea also present. The quarry is a renowned variety of limestone flora, producing a Helleborine. location for migrant birds in the autumn secondary Magnesian Limestone Spleenwort grows on the cliffs. with a regular show of common migrants grassland. This rare habitat supports a Location Northern Brown Argus butterfly and and the occasional rarity. range of orchids such as Pyramidal, Situated half a mile north of the Cistus Forester moths can be found on Common Spotted, Bee and Fragrant village of Bishop Middleham on a the cliff slopes. orchid and most importantly a large minor road linking Bishop number of Dark Red Helleborines. The Middleham to the A177. Car parking Marsden Old Quarry The beaches at Blackhall suffered from a sparse grassland of the quarry floor also is restricted to two lay-bys on the century of dumping of colliery spoil supports Blue Moor Grass, Moonwort, west side of the road. from the undersea deep coal mines of Autumn Gentian and Fairy Flax along with General information Location Grid Ref: NZ331326. Parking and access at the north end of Lizard Lane in Marsden opposite the www.wildstock.co.ukphoto: caravan park.

General Information Grid Ref: NZ395645 OS Explorer map no. 316

Managed by South Tyneside Council. Full details are available on the South Tyneside Council website.

50 Marsden Old Quarry Bishop Middleham Quarry 51 photo: www.wildstock.co.ukphoto: can be seen in the stream bed near www.wildstock.co.ukphoto: Crimdon sand dunes the railway viaduct where the Magnesian Limestone is exposed. The wooded sides are an example of ancient semi- natural coastal woodlands characterised by their by Ash and Wych Elm canopy domination. Unfortunately, many of the elms have succumbed to Dutch elm disease in recent years However, a few can still be seen along the Blackhall meadow stream sides. The grasslands in the base of the valley are maintained for Blackhall Rocks recreational use.

The coastal slopes comprise a mosaic the Durham coast. Since dumping Grid Ref: NZ470392 DWT website. Wort, Saw-Wort and Dropwort. of habitats including the nationally ceased the natural currents of the OS Explorer Map No. 308 important paramaritime Magnesian coast have begun the process of Managed by Durham Wildlife Trust full Location Limestone grasslands that support a gradually moving the pit waste. details of the site can be found on the The Leas Access and car parking are off the Coast rich variety of wildlife. Notable Description Road between South Shields and Souter photo: www.wildstock.co.ukphoto: species here include Sea Plantain, Location Lighthouse. A large cliff top site showing classic Thrift and Bloody Crane’s-bill. East of . From the examples of coastal erosion including crossroads on the A1086 at Blackhall General Information stacks, arches and wave cut platforms. The sand dunes are of particular Rocks village, follow the minor road OS Grid Ref: NZ395657 It is the largest area of semi-natural interest for their species-rich flora and under the railway bridge and down OS Explorer map no. 316 grassland in South Tyneside ranging include many nationally scarce towards the beach. There is a large car from neutral to limestone. species including Rush-leaved Fescue park on the right of the road or taking Managed by the National Trust further A particularly rich area known as Rocket and Spring Cinquefoil. The beach the left hand fork leads to a very small information is available from the Green (opposite the old limekilns) holds supports an internationally important car park just above the cliff tops. National Trust website. many typical Magnesian Limestone breeding population of Little Tern grassland species plus rarer wild flowers during late spring and summer. General information Common Rockrose like Bee and Pyramidal Orchid, Yellow- Crimdon Dene Location photo: www.wildstock.co.uk Description Crimdon Dene can be accessed from Crimdon Dene contains a variety of the A1086 between Hartlepool and special habitats ranging from the Blackhall Rocks at grid reference NZ ancient semi-natural woodlands in the 478 372. Ample car parking can be Dene to the sand dunes and found at the promenade overlooking paramaritime Magnesian Limestone the beach. grasslands found on the coastal slopes. General information The Dene itself is a wide valley cut Grid ref NZ478372 through boulder clay into the OS Explorer Map no. 306 Magnesian Limestone and the overlying The Leas boulder clay drift deposit. Both layers The dene is managed by Council and further 52 53 photo: Dave Mitchell Dave photo: photo: www.wildstock.co.ukphoto: for butterflies such as Dingy Skipper and Common Blue. Location About 2 miles south of Sunderland city centre and accessible on foot from Ashbrooke, Grangetown, Ryhope and Tunstall.

photo: www.wildstock.co.ukphoto: Car parking is reached by turning up the track to Tunstall Hills allotments from Leechmere Road, and parking at the Changing Rooms car park. Cassop Vale Castle Eden Dene General Information Grid ref NZ395543

photo: John Bridges John photo: OS Explorer Map no. 308 information is available on Easington Globe Flower. Northern Brown Argus the ancient trees can be found Yew, DC website. Butterfly can also be found. Oak, Ash and Wych Elm along with an Tunstall Hills are managed by Location understorey of Hazel, Guelder Rose, Sunderland City Council and further Cassop Vale The reserve is five miles south east of Privet, Dogwood and Spindle. details can be obtained from their National Nature Reserve Durham City on the edge of Cassop website. village. The reserve entrance is The dene also supports Blomer’s Rivulet Description immediately opposite the Cassop village moth. Cassop Vale offers a unique opportunity post office with parking in the village. Castle Eden Dene to see primary Magnesian Limestone National Nature Reserve The dene mouth has calcareous to grassland, scrub, ancient limestone General information neutral grasslands with Bloody woodland and wetland on one site. Grid Ref: NZ335387 Description Cranesbill on the slopes and Pale St The woodlands have Bird’s Nest Orchid, OS Explorer map no. 305 Castle Eden Dene is the largest John’s-wort in the meadow. The two Bluebell and other typical woodland area of semi-natural woodland in famous historical colonies of the plants; the grasslands support the full Managed by Natural England. North East England. It occupies a Northern Brown Argus butterfly are still range of Magnesian Limestone grassland Full details can be found on the NE steep-sided ravine cut through glacial present and Slowworms have recently species, with Moonwort, Frog Orchid and website. deposits deep into the Magnesian been recorded. Limestone. The dene vegetation is a photo: www.wildstock.co.ukphoto: Tunstall Hills survivor of the wild wood which once Location Globe flower covered most of Britain. Car parking and visitor centre are at Local Nature Reserve Oakerside Dene Lodge in Peterlee, the Over 450 species of plant have been reserve is sign posted from the A19 and Description recorded in the wood, many of which from Peterlee town centre. Thes prominent hills mark the outcrop of are typical of ancient woodlands that the ancient barrier reef and include date back to pre-medieval times. Spring General Information internationally famous exposures of flowers include Bluebell, Primrose, Wood Grid Ref: NZ428393 fossiliferous reef limestones. They support Anemone, Ramsons and Early Purple OS Explorer map no. 308 a typical limestone flora including, Blue Orchid. Rare and unusual plants found Moor Grass, Common Rockrose, Small in the dene are Birds Nest Orchid, Herb The reserve is managed by Natural Scabious, Frog Orchid, Bee Orchid and Paris and Lily Of The Valley. Amongst England and further details can be Tunstall Hills Autumn Gentian. The reserve is also good 54 55 Photography Natural England Durham County Council District of Easington Quadrant Durham County Council Council Offices www.wildstock.co.uk contact: Darin Smith Newburn Riverside County Hall Seaside Lane email: [email protected] Newcastle upon Tyne Durham Easington NE15 8NZ DH1 5UL Co. Durham John Bridges SR8 3TN Tel: 0191 2295500 Tel: 91 3834567 www.northeastwildlife.co.uk www.naturalengland.org.uk www.durham.gov.uk Tel: 0191 5270501 www.easington.gov.uk National Trust South Tyneside Council Souter Lighthouse Town Hall & Civic Offices Durham Wildlife Trust Coast Road Westoe Road Whitburn South Shields Chilton Moor Sunderland Houghton-le-Spring Tyne and Wear NE33 2RL Tyne & Wear SR6 7NH DH4 6PU Tel: 0191 4271717 Tel: 0191 5293161 www.southtyneside.info Tel: 0191 5843112 www.nationaltrust.org.uk www.durhamwildlifetrust.org.uk Sunderland City Council Durham Heritage Coast Civic Centre Durham Biodiversity Partnership C/O Environment Burdon Road Rainton Meadows Durham County Council Sunderland Chilton Moor County Hall SR2 7DN Houghton-le-Spring Durham DH1 5UQ Tyne & Wear Tel: 0191 5205555 DH4 6PU Tel: 0191 383 3351 www.sunderland.gov.uk www.durhamheritagecoast.org Tel: 0191 5843112 www.durhambiodiversity.org.uk

Magnesian Limestone cliffs near Crimdon photo: www.wildstock.co.uk

56 57 photo: www.wildstock.co.uk

DURHAM

Wingate Quarry LNR

58 MAGical meadows and the Durham Magnesian Limestone

ISBN - xxxxxxxx-xxxxx-xxxxxx-xx Published by Durham Wildlife Trust © 2007

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