TRANSACTIONS THE HEATHLANDS OF THE EAST SUFFOLK SANDLINGS PATRICK H . ARMSTRONG
Introduction The Sandlings region is the strip of country underlain by Pleistocene and Pliocene Crag deposits, about five miles in width, extending from Ipswich to just north of Lowestoft. For centuries it has consisted of a mosaic of several distinct land use types—open heathland, arable, and the drained marshland pasture in the Valleys of rivers flowing eastwards across the region (the Aide and Blyth, for example) and close to the shore. These three types of land have long complemented one another; thus the Sandlings heaths, although their soils are often acid and of no great fertility, have had an important part to play in the economy of the region for many centuries. There has been a number of changes in the ecology of these heaths in recent years. The populations of many species of heathland birds have declined spectacularly. The stone curlew was breeding in appreciable numbers in almost every coastal parish from the Orwell estuary to Covehithe in 1956, but in recent years only about four pairs have bred. Other species—the nightjar, stonechat, whinchat, woodlark, and wheatear—have also decreased. The populations of several reptiles and an amphibian (the natterjack) have been reduced, and some heathland insects such as the silver-studded blue now have a much reduced distribution. These changes may be most clearly understood in the context of the complex of inter-related changes in the East Suffolk countryside as a whole. Origin and land use history Although evidence is mounting to support those who maintain that the contribution of Mesolithic man to the clearance of Britain's forests was by no means negligible (Dimbleby, 1962), it is still widely believed that the heathlands of lowland Britain date from the Neolithic. Professor Godwin's (1944) study of the pollen succession of Holkham Mere showed that a striking change in the Vegetation of Breckland from a closed mixed oak forest Community to one in which non-tree species predominated—ericoids, grasses, and bracken—coincided with the beginnings of Neolithic culture in the area, suggesting that the clearance of the forest had resulted in the formation of the heath Community. More recently the work of Perrin and others (1964) in dating the organic material in Breckland soils by residual radiocarbon has given additional support to this view.
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The proximity to the surface of layers of flints in the Upper Chalk in Breckland facilitated their exploitation with the antler axe-picks of the early Neolithic, and there have been a large number of Neolithic finds in this part of western Norfolk and SufFolk. The pall of sandy material that overlies much of the area, which although of limited fertility, is easy to work, enabled these earliest farmers of East Anglia to practise a primitive agriculture. Maps, such as those prepared by Sir Cyril Fox (1933, 1952), of the distribution of prehistoric sites and finds (e.g., round barrows, bell beakers) show an important concentration of localities in Breckland for the Neolithic and Bronze Ages. While the clay area of high Suffolk is almost devoid of any Neolithic or Bronze Age material, another concentration appears in the Sandlings. A number of Neolithic axes have been found near the heads of the Orwell and Deben estuaries, and there are about fifty Bronze Age barrows in the coastal sands region, particularly in the parishes of Martlesham, Brightwell, Waldringfield, and Foxhall. The similarity of the present day Vegetation of the Sandlings to that of Breckland, together with analogies in the proven prehistoric occupance of the area, suggest that the heathlands originated at about the same time and in the same way. Certainly the isolated fragments of ancient woodland, such as Staverton Thicks, are of the oakwood type. The archaeological evidence strongly suggests that the southern Sandlings was an "entrance area" for newcomers from the continent in Neolithic and Bronze Age times and in the later Bronze Age there was a relatively dense population (Clarke, 1960). It may well be that these early farmers fanned out from estuaries, Clearing patches of the closed forest for their crops on the sandy plateaux. When these were abandoned, the non-tree plant species that characterise the heathlands today established themselves. Unfortunately, there have as yet been no pollen studies or radiocarbon determinations that might confirm this hypothesis. Other invasions followed; thus about A.D. 500 the "Ipswich People", a group of warriors with Scandinavian affinities, moved into the Sandlings. They speedily dominated the region, making Rendlesham their royal seat. Their royal cemetery has been found close by at Sutton Hoo. However, the impact on the landscape of some of these groups may have been small, for there seems to have been some continuity of agricultural practices from the later prehistoric period through to the Dark Ages. The Domesday record reveals a striking contrast between the heavily wooded Boulder Clay upland and the Sandlings; several upland vills had pannage for upwards of 800 swine in 1086. The largest area of woodland in the coastal belt was at Leiston, where
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there was food for 200. At Thorpe there was pannage for twenty swine and at Westleton seven; in most places there is no mention of woodland. The figure for the density of plough-teams per Square mile, which might be expected to give an indication of the proportion of arable land is also lower near the coast than inland (Darby, 1957). If the proportion both of woodland and arable was substantially less than in high Suffolk, quite large areas must have been uncultivated waste, in all probability supporting heath Vegetation. Support comes from Domesday references to bee-keeping in the Sandlings region. Two hives of bees are recorded at Westleton and seven at Leiston; renderings of honey are mentioned from elsewhere, e.g., from Blythburgh and Ipswich. T h e comparison with Breckland is perhaps again of interest; as many as twentyseven hives are recorded for Methwold in the Norfolk Breck, irnplying that in the eleventh Century, as today, hives were set out so that nectar could be collected from expanses of heather. Sheep grazed the heaths at this time; the entry for Leiston records 112 sheep on the demesne lands, at Westleton there were sixty sheep and at Chillesford 100. Goats, too, were quite abundant in the Sandlings, and herds of up to sixty are mentioned —there were twenty-four alongside the sheep at Westleton. Sheep and goats between them would have prevented the recolonisation of the heaths by tree seedlings. Although frequent references to cattle occur in Domesday and in very many later documents (Armstrong, 1970), it is with sheep that the heaths of the Sandlings have been particularly associated. A 1576 document reveals there were 500 sheep on the lord's heath near Benacre (Suckling, 1848), and a set of accounts preserved in the Ipswich and East Suffolk Record Office (Ref. HA 30: 30/50/ 22/27.3) showing the management of flocks at Westwood, near Blythburgh, in the years 1646-7 indicates that there were about 1,000 sheep pastured on the heaths of that manor in the summer of 1646. Other documents, now in the British Museum (Add. MSS. 22249), reveal that a flock of similar size existed on the Friston Hall estate in the parishes of Aldeburgh, Friston, Snape, and Hazlewood in the later y e a r s of the seventeenth C e n t u r y . In 1795 Arthur Young wrote: " T h e dry heaths are to be profitably managed only by sheep being made the principal object, and all the tillage of the farm absolutely subservient to them". T h e landed estate of the time was a closely integrated system; each estate contained some heathland ("sheepwalk"), some arable land, some drained marsh or lowland pasture, and sometimes an expanse of saltmarsh. T h e flocks would graze over the heaths for part of the year—often the early summer—clover being grown on some of the arable for fodder later in the season and turnips cultivated as
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winter food for the sheep. These crops were generally grazed from the fields, the sheep dung fertilising the ground prior to the taking of wheat crops. T h e marshland pastures of the Valleys were often used when the other sources were not available, particularly in very cold weather. A typical property was Westwood Lodge Farm, which in 1767 was made up of 402 acres of drained marshland, 622 acres of arable, and 1,526 acres of heath or sheepwalk (Ipswich Record Office HA 30: 30/50/22/5.1). When Arthur Young visited the estate in 1795 1,600 sheep were kept, and documents reveal that under the terms of his lease the tenant had to keep at least 800 sheep and "to fold them at all reasonable times with the usual number of hurdles upon some part of the farm most likely to be benefited thereby". Actually, it seems as though this approach to land management, the integration of arable and sheep enterprises, was, even by the time that Young wrote, a long-established practice; in the sixteenth and seventeenth centuries sheep flocks had grazed for part of the year over the Sandlings heaths, while at other times they were folded on the arable prior to its being "ploughed for barley" or some other cereal. A nineteenth Century observer shows that the continuity was maintained: "Whins, fern and ling grow . . . along most of these heaths . . . Large flocks of sheep are fed on these heaths and folded on adjoining land" (Raynbird, 1849), and Evans (1956) has shown how entwined were the traditions and social structure of the Sandlings village with the management of the sheep flock until within living memory. Indeed, as recently as the First Land Utilisation Survey in the 1930s the pattern does not seem to have been very different; Butcher (1941) wrote: ". . . sheep are the mainstay of the arable farmers . . . T h e sheep run for the most part on the heaths and poor grassland in the summer, are folded in the green crops in the autumn and stall fed on the roots in the winter". Certainly for about a thousand years, and perhaps for a great deal longer, the farmers of East Suffolk have depended on the sheepwalks for their stock's summer grazing. T h e heaths were therefore as carefully managed as the arable lands and lowland pastures that they complemented. T h e aim was, as Arthur Young put it, to secure "a good covering of furze and ling". With this in view, the heaths were regularly cut and burnt. There were yet other pressures maintaining the open character of the heaths. T h e rabbit was probably introduced in about the twelfth Century (there is no mention of coney-warrens in Domesday). "Warren" and "coney" are quite common place-name elements in the Sandlings, and certainly by the very early 1400s there were warrens on many of the heaths of the region. T h e court rolls of many manors include mentions of punishments meted out to those who poached; thus in Walton-cum-Trimlev in 1406
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a jury f o u n d " . . . that John Brownings did trespass in the warren of the L o r d in taking conies there with one dog. T h e r e f o r e amerced 3s. 4 d . " (Ipswich Record Office H B 8: 1112). T h e r e was a coney-warren on the heath at Benacre in 1576 (Suckling, 1848) and a lease exists of another near Blythburgh at about the same time. Old game books reveal that the warrens were carefully cropped until well into the present Century, and leases sometimes speit out the management policies to be adopted in some detail. T h e history and ecology of the rabbit in Suffolk will be described in a f u t u r e paper (Armstrong, in preparation) and it suffices to say here that grazing by rabbits on the Sandlings heaths has supplemented that of stock for at least six centuries. T h e Sandlings heath is t h u s a far f r o m natural Community; if it is ungrazed and u n b u r n t scrub soon develops. T h e heathland plagioclimax is the result of an equilibrium being maintained between the normal seral change—scrub invasion—and the pressures described above. The
fluctuating
extent of the heaths
Although this continuity in the use of the heaths has been maintained, changes in emphasis have occurred. T h e boundary between the heaths and t h e adjoining ploughed land has long been a fragile one. T h e r e have been periods of advance of arable into the heaths, times of food scarcity, such as the Napoleonic W a r s and the First and Second World Wars, interrupted by short phases of retreat when agricultural prices feil, as in the later years of the nineteenth Century, or between the two World Wars. T h u s the T i t h e Survey of Benacre (Public Record Office Ref. No. I R 18/9586), made in the early 1840s reveals that at that time substantial acreages had been withdrawn f r o m the plough and were falling back to heathland. While m u c h of T i n k e r ' s Walks, between Walberswick and Blythburgh, is shown on early O r d n a n c e Survey m a p s as farmland, some of it is clearly shown as heath on the First L a n d Utilisation Survey m a p of the 1930s; but by 1949 a substantial tract had again been ploughed. N o t far distant f r o m this locality, part of East Hill, in Walberswick parish, is shown as farmland on Ordnance Survey maps m a d e before 1946. T h e 1956 edition, however, shows some of it to have reverted to heath and it now supports a considerable growth of young conifers. M a n y other examples could be instanced. Unquestionably, however, the overall trend has been one of reduction in the area of heathland. A m a p m a d e by Faden in 1783 suggests that there was an almost continuous block of heathland between the Aide and the Deben, and the accounts of contemporary travellers such as Y o u n g confirm this impression. By the 1840s it had already been broken into a n u m b e r of fragments.
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T h e 1889 Ordnance Survey maps show that there were about 19,000 acres of heathland in the Sandlings. Only about 40% of this total remains, and its disappearance continues. In fact, the greatest assault on the heaths has come in the last two or three decades; between 1949 and 1964 some 3,000 acres of heathland in the south Sandlings parishes were reclaimed (Trist, 1969). Changes in land u s e T h e striking reduction in the nuinbers of sheep in this traditionally sheep-arable district is principally responsible for the recent acceleration of this long-continued decline. Whiting (1967) showed that the number of sheep per 100 acres of crops, grass, and rough grazing in twenty-four Sandlings parishes feil from 42-8 in 1938 to 12-1 in 1962. T h e war-time policy for the eastern counties was to emphasise arable crops for human consumption, and other factors were the extremely high labour costs involved in folding flocks on arable land under the conditions of the depressed agriculture of the period befoie the Second World War, together with the Virtual impossibility of obtaining shepherds. T h e introduction of new fodder crops (e.g., swedes, beet, mangolds), causing a reduction in the flocks' dependence on the heathland grazings in the early nineteenth Century, as well as an increased demand for cereal food through continuing population growth, account for the gradual reduction, albeit with occasional temporary readvances, in the area of heath over the last two hundred years. T h e quite abrupt disappearance of the sheep—the ecological link between the heaths and the nearby arable and pasture—resulted in the isolation of the heathland. T h e heaths now no longer have a function within a larger agricultural system and so are being rapidly taken over for other uses. T h e severance of this link coincided closely with a number of other developments, some technical, some economic. It was a Sandlings farmer who in 1947 was the first in Britain to use summer irrigation; Penman (1952) noted substantial increases in the yield of sugar beet per acre at Kesgrave, near Ipswich, when this technique was used, and it is now quite widely employed in this district of light sandy soils and low rainfall. Trace element deficiencies (boron, magnesium, and copper) were recognised on the highly acid heathland soils and the means found of correcting them; also developments in liming techniques enabled the acidity of the heathland to be corrected more satisfactorily than had been possible previously. Moreover, agricultural subsidies operate so that there are financial incentives to landowners to reclaim heathland; contributions may be obtained towards the cost of lime and fertilisers as well as grants for ploughing "difficult" land. Although margins are not large, these factors taken together have meant that recently it has become more profitable to put heathland under the plough (Field, 1966).
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Although reclamation for agriculture has been most responsible for the inroads to the heathland, large areas have been taken for forestry. The Forestry Commission occupies some 8,646 acres in the region—Aldewood Forest—and almost all of this is now planted; much, but by no means all, of this land was heath when acquired by the Commission. The main planting effort was in the first two decades of the Commission's existence; 3,798 acres had been afforested by 1930 and 5,723 by 1940. Virtualiy no planting was done during the Second World War, but the pace increased again about 1950. Most of the early plantations were of Scots pine, but now Corsican pine is almost exclusively used as it has been found to give greater yields in a shorter time, although small areas are planted with broadleaved species (oak, beech, and poplar) for experimental and amenity purposes (Searle, 1967, 1968). About 1,250 acres of heath have been developed as golf courses; significantly the main periods of links construction were the 1880s, 1890s, and the 1920s, periods of agricultural depression when land was reverting from arable to heath and the price of land had fallen. Included in the same category of recreational use of land would be the fifty acres of Foxhall Heath acquired for a motor racing circuit, in Operation since 1952. Defence uses have claimed over 1,000 acres of heath. Several hundred acres were acquired for Martlesham airfield before the Second World War (but this area has been declared surplus to Ministry requirements and has been disposed of to a property Company) and war-time and post-war requirements led to the establishment of R.A.F. Woodbridge and Bentwater. This involved some heathland, conifer plantation, and farmland being taken over. Smaller acreages of heath have disappeared through urban development, particularly near Ipswich, and for sand and gravel working. The ecological eftects of the changes The ploughing up of the heathland and the application of lime and fertilisers result in the destruction of most of the podzolic soil profile, including, sometimes, the iron-humus pan by deep ploughing methods, and there are few heathland organisms able to survive such disturbance. The com bunting and possibly the meadow pipit are almost the only vertebrate species regularly found in both arable land and heathland habitats. It is, perhaps, significant that the com bunting appears to have extended its ränge in Suffolk slightly since 1930 (Payn, 1962). In a study of the ecological effects of changes in land use of the Dorset heaths, Moore (1962) noted that strips of gorse, bracken, and scrub may be
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left as hedges, and other heathland plants and animals survive within these strips for a decade or so. Such strips were left less frequently in the Sandlings, but as in Dorset, gorse and the heathers were eventually displaced by characteristic hedgerow species such as hawthorn and bramble. T h e intermingling of cereal fields and heaths renders the input of agricultural chemicals into the fragmented heathland communities more likely. The red-backed shrike, close to the end of a food-chain has been adversely affected; an egg from a nest on heathland at Minsmere, in 1963, in which four out of five eggs failed to hatch was found on analysis to contain quantities of D . D . T . and chlordane (R.S.P.B. documents at Sandy, Bedfordshire). There are few changes in the first five years or so following the planting of an area of heathland with conifers; but as the pine trees overtop Vegetation heathland species are phased out. The stonechat and the red-backed shrike soon disappear. Heathland insects such as the grayling, and reptiles, e.g., the adder and lizard, may survive in the broader forest rides even when these are bordered by trees over 30 feet in height. The heathers and gorse are amongst the species to persist longest. T h e ecological effects of a change in land use from open heathland to golf course vary. Patches of grass-heath and gorse may be retained as "rough", and here typical heathland species of insect and reptile may be found. Grazing and buming may be eliminated and there is a tendancy for gorse to grow up to form what is almost a single-species Community. fleavy trampling tends to eliminate the ericoids and almost continuous disturbance may result in the avoidance of golf courses by species of birds for which the habitat might otherwise be suitable. Many of the coastal heaths were used by the army during the Second World War. The microtopography of many of the heaths has been modified by the digging of trenches, as on East Hill, Walberswick and the use of tracked fighting vehicles; air photographs taken twenty years after the use of heaths by the military revealed traces of track marks. Destruction by building airfields and other installations is much more extensive. Military training may have the effect of turning over leached surface material and bringing up of fresh mineral nutrients for the Vegetation (Simmons, 1964). Where gravel is dug drastic changes occur. However, after the quarries have been worked out or abandoned, re-invasion by heathland species occurs. Three sand pits on Westleton Heath were abandoned during the war, and air photographs taken in 1945 show quite substantial areas of bare ground, about half of which
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had been invaded by bracken by 1955. Small pits dug on Walberswick Common in the early 1950s had both heather species well established in them within three years and provided a habitat for several species of heathland lepidoptera and reptiles. It was argued by Moore that mineral workings provide a greater ränge of microhabitat, and therefore show a more varied assemblage of organisms than undisturbed heathland. The heathland r e m n a n t s Arthur Young wrote of the Sandlings sheepwalks in 1795: "All these heaths will disappear in time". Perhaps it has taken longer than he anticipated, because, as explained above, there have been cycles of reclamation; periods of rapid advance into the heaths have been interspersed with phases of consolidation or retreat. But probably within a generation there will be little heathland outside specially protected reserves. Areas of heathland at present conserved in this way include the 117 acres of Westleton Heath purchased by the Nature Conservancy from the Forestry Commission in 1953 and designated a National Nature Reserve in 1956 and areas of heathland within the R.S.P.B. reserves at Minsmere and near Aldeburgh. Adjoining Minsmere is an area of 214 acres of heathland and cliff which has been the property of the National Trust since 1967, when it was bought from the Dunwich Town Trust as part of the Neptune Appeal. Certain other areas of heathland have been designated Sites of Special Scientific Interest (e.g., Snape Warren). Designation of an area as a S.S.S.I. does not involve any change in ownership of the land, but places a duty on the Local Planning Authority to consult with the Conservancy if any change in the use of the land is envisaged. The disappearance of stock from the heaths in the inter-war years did not end the cropping of the heaths. T h e rabbits remained, and their grazing prevented the invasion of the heathland communities by scrub. However, myxomatosis was first reported in East Suffolk from Easton Bavents on 2nd December, 1953 (Haslam, 1955) after appearing in K.ent in October of that year. It spread throughout the Sandlings in 1954. An examination of game books for several Sandlings estates reveals that where several thousand rabbits were taken on an estate in the 1953 season, only a dozen or so were shot the following year. T h e almost complete extermination of a species so important in the heathland ecosystem as the rabbit had far-reaching ecological repercussions. Thus the average annual kill of hares on one sporting estate in the district was 213 for the ten years prior to myxomatosis, and 692 for the ten years following the outbreak. Game records also reveal that the stoat almost completely disappeared, although there is evidence that an early effect of the rabbits' disappearance was the deflection of food-chains and there were reports that in
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both 1954 and 1955 there was increased stoat predation on groundnesting birds such as the wheatear. T h e effects on the plant communities were equally immediate; as early as 1955 the absence of rabbits had resulted in a more vigorous growth of grasses, and many species were flowering and seeding where in previous years grazing has been extremely heavy and few grasses had ever flowered (Conder, 1955). Many heaths that had supported an open heather Community in 1954 now became tangles of birch, bramble, and eider. A number of heathland bird species, such as the stonechat, depend on the open areas for food, and myxomatosis may have contributed towards their decline. While the total area of unenclosed open heathland has decreased spectacularly over the last three decades, recreational pressures on what remains have increased strikingly. It is difficult to quantify this increase, but figures from the Road Research Laboratory automatic traffic counter, in use since 1956 on the B1387, a road that runs from the A12 to the populär holiday village of Walberswick, give some indication of its magnitude. The average number of vehicles per day rose from 413 in 1956 to 821 in 1968. T h e average traffic for the month of August now runs at a little over 1,500 per day, up to 2,500 on Sundays, and nearly 3,500 on fine summer Bank Holidays. Locally, therefore, the Problems of trampling, litter scattering, the picking of plants, and disturbance of wildlife are very real. (Before the ceremony marking the handing over of Dunwich Heath to the National Trust in 1968, fourteen sacks of litter had to be removed.) Another consequence of the increasing use of the heathlands for recreation has been the intermittent starting of quite serious fires; the average number of heath fires per annum in East Suffolk since 1962 has been ninety-five. About 230 acres of heath are destroyed each year by burning (I pswich and East Suffolk Fire Service statistics). Fires are often caused by visitors throwing down lighted cigarettes or abandoning picnic fires before they are completely extinguished. Such a heath fire was started on 15th April, 1968 (Bank Holiday Monday) on Dunwich Heath. About twenty-five acres were burned before the fire spread to the Minsmere Bird Reserve. This reserve has in fact sustained several quite serious fires, the most devastating in 1956, when the conflagration burned for four days and three nights. It has been suggested that burning is detrimental to the heathland ecosystem as it results in the loss of plant nutrients from the system. However, work on heathlands in Dorset has recently shown that burning losses of such nutrients such as sodium, potassium, calcium, and magnesium were probably more than
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compensated by an input of nutrients dissolved in rainwater. Only in regard to nitrogen and phosphorus did an overall loss result (Chapman, 1967). Regulär, controlled burning of the heaths is a management technique which has been used to maintain the open character of the heaths for grazing for generations. However, severe burning tends to reduce the variety of species in the heathland Community; litter and decomposer organisrns are destroyed, as well as the layer of grasses and bryophytes covering the soil, although heather, bracken and gorse roots may survive underground. This may render the whole system unstable as bare soil is exposed and made liable to wind erosion. Although "blowouts" on the scale of those in Breckland do not occur in the Sandlings, the fine material of the topsoil may be blown away leaving a pavement of bleached white flint pebbles. Several examples may be seen on heathland near Westleton. Scottish experience suggests that when heather over fifteen years old is burnt, the woody stems generate sufficient heat to damage the roots. Regeneration then has to take place from seed, and bracken, in particular, may well invade and become established before the heather can grow up again (McNaughton, 1959). However, Nature Conservancy experiments at Westleton Heath seem to suggest that autoscything of heather of comparable age followed by burning of the cuttings did not, in the Sandlings heathland Situation, hasten bracken invasion (Nicholson, 1968). The problem, may therefore be quite complex, grazing and burning interacting in a number of subtle ways, the effects varying with the compositum of the flora and the age of the stands. Certainly on a number of Suffolk heaths there has been considerable spread of bracken in the last decade or so. Whether this is the result of the cessation of grazing by stock and/or rabbits, the discontinuance of controlled burning, the increased incidence of fierce uncontrolled fires, or even a climatic change, or a combination of several of these factors is difficult to say. One might add that very recently a paper has appeared describing decline and death of bracken on a Sandlings heath (Garrett-Jones, 1969). T h e problem is of considerable complexity. The efTect of a serious heath fire on the animal communities can be devastating. As long ago as 1932 Ticehurst deplored the consequences of these burnings on the wildlife of East Suffolk. The populations of certain heathland specialists, such as the stonechat and red-backed shrike amongst the birds, may be fewer than a dozen or so pairs and confined to two or three of the region's heaths, and thus a single fire could virtually eliminate a species. Fires probably contributed to the extinction of the Dartford warbler from the Sandlings heaths in the 1930s (Payn, 1962). Some invertebrates, such as the silver-studded blue butterfly similarly have highly restricted distributions and are equally vulnerable.
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Summary and conclusion Although t h e reclamation of heathland in the Sandlings has been a long-continued p h e n o m e n o n , with the graduai disappearance of the sheep f r o m the heaths since about 1920, and the resulting ecological isolation of the sheepwalks f r o m the surrounding land use types, the rate a t w h i c h the total areaof heathland has been declining has recently accelerated. As well as reclamation for arable and afforestation, substantial acreages have been converted into gravel pits and golf-courses, acquired by the D e f e n c e d e p a r t m e n t s or used for u r b a n development. Grazing pressure, already reduced with the cessation of stock grazing on the heaths, was virtually eliminated (for a time at least) w h e n myxomatosis removed the rabbit in 1954. Invasion by scrub and other ecological changes have ensued. In addition the Sandlings heaths have experienced growing recreational pressure, particularly since the early 1950s. T h i s has resulted in intermittent catastrophic fires and has led to serious wildlife disturbance. T h e s e changes have been accompanied by alterations in the pattern of agriculture such as the g r u b b i n g of hedges and the use of chemical pesticides on a wide scale. Simultaneously there has occurred a significant change in climate which may have affected a n u m b e r of heathland birds indirectly (Kalela, 1949). F r o m the conservation Standpoint it is u n f o r t u n a t e that so many t r e n d s have coincided. Fluctuations in the population of organisms, as t h e result of climate, for instance, are of the normal order of things, and n u m b e r s are usually speedily m a d e u p . But w h e r e several pressures—habitat destruction and change, partial sterility due to pesticides, increased predation, for example— coincide with a long-term change in climate, recovery may be impeded. W i t h birds special considerations apply: as the specialised heathland habitat becomes f r a g m e n t e d and the small heaths widely spaced breeding may be restricted by the fact that individuals have difficulty in finding mates, and while a single heath may not supply sufficient food for a brood of young, movem e n t between several heaths would be very wasteful of energy; also where a very low population density exists, the level of social Stimulation may be insufficient to induce breeding. T h u s while some of the changes in land use, etc., detailed above m a y marginally have improved an environment for particular species of organisms, almost u n d o u b t e d l y the result of the sum total of t h e m has been to reduce t h e ecological variety and biological interest of the Sandlings heathland zone. Only speedy
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d e s i g n a t i o n o f a r e a s of h e a t h l a n d of s o m e s i z e a s a r e a s f o r s p e c i a l protection can prevent further biological i m p o v e r i s h m e n t of the r e g i o n . A t t e m p t s should be m a d e to secure areas containing a variety of microhabitats, a n d there m i g h t b e a case for the re-introduction of sheep grazing on s o m e of these on a n experim e n t a l b a s i s in a n a t t e m p t to p r e s e r v e t h e m o s a i c o f p l a n t c o m munities that h a s characterised the S a n d l i n g s for m a n y centuries.
References Armstrong, P. H. (1970). The Heathlands of the Suffolk Sandlings in their settmg: a Systems Approach to Landscape Study. Unpublished thesis, College of Arts and Technology, Cambridge. Armstrong, P. H . (in preparation). in Suffolk. Butcher, R. W. (1941). London. Chapman, S. B. (1967). the south of England.
T h e history and ecology of the rabbit
The Land of Britain—Suffolk
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Patrick H. Armstrong, School of Geography, Technology, Collier Road, Cambridge, CB1 2A Cottenham, Cambridge.