Recent changes in the land use and ecology of the East Suffolk Sandlings

RECENT CHANGES IN THE LAND USE AND ECOLOGY OF T H E EAST SUFFOLK SANDLINGS PATRICK H .

ARMSTRONG

In the late 1960s, I undertook a programme of research on the heathlands of the East Suffolk Sandlings. One of the objectives of that study was to establish the manner in which changes in the land use of this coastal area were related to changes in the ecology of the heaths, and, in particular, to alterations in the status of characteristic heathland 'indicator' organisms.

The results of these researches were recorded in these pages (Armstrong, 1971) and elsewhere (Armstrong, 1970,1972,1973,1974 and 1975). Much of my time since the early 1970s has been spent overseas, but a visit to eastern England during 1982-1983 gave me an opportunity to review more recent changes in the land use and ecology of the region and to prepare a brief report.

The Sandlings heaths up to 1970: a summary At the time of my earlier study the Sandlings region was defined as the 'strip of country underlain by Pleistocene and Pliocene Crag deposits, about five miles (8km) in width, extending from Ipswich to just north of Lowestoft'. It was shown that it comprised a mosaic of land use types - open heathland, arable and drained marshland pasture - that had complemented each other for many centuries. Sheep were the vital link that maintained the integrity of a tightly-knit structure. For many generations the flocks had grazed over the heaths for some months, and over arable land (upon which clover and turnips were grown to be grazed from the fields) and the drained marshes along the coast and in the Valleys, for other parts of the year. In 1795 Arthur Young had advised: 'The 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'. Half a Century later Raynbird (1849) observed 'whins, furze andlinggrow. . . along mostof these heaths . . . large flocks of sheep are fed on these heaths and folded on adjoining land.' Each holding thus had areas of heathland ('sheepwalk'), lowland pasture and arable: sometimes to maintain the 'good covering of furze and ling' the heathlands were cut or burnt (Young, 1795).

The open character of the Sandlings heaths was also maintained by the heavy grazing of rabbits (Oryctolagus cuniculus): certain areas of heath were specially set apart and carefully managed as coney-warrens. Some of these warrens had been in existence at least since the fourteenth Century. There is evidence that sheep and rabbits grazed the same areas, and to some extent took different plant species. Certainly a rabbit warren would provide an additional source of income for an estate, and, in emergencies, of animal protein for the peasantry, and thus contributed further to the level of integration displayed by the Sandlings area land use system.

From the time of the First World War onwards, sheep husbandry declined.

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Economic returns feil, and it became difficult to obtain shepherds. This quite abrupt severance of the links between the heaths, and the pasture and arable land, resulted in the ecological isolation of the former, and hence a fall in their monetary value and their being taken over by other uses. This change coincided with, or was closely followed by, a number of other social, technical and economic changes that caused the trend to accelerate during the period 1920-1970. These included: 1. The S o l u t i o n o f t h e t r a c e e l e m e n t problem f o r l i g h t - s o i l e d , arable l a n d .

2. The development, since 1947, of summer irrigation.

3. The U . K . agricultural subsidy structure which provided incentives for heathland reclamation.

4. The establishment of the Forestry Commission in 1919, and its subsequent aggressive land-acquisition policies.

5. Expansion of the region's population, with a resulting increased demand for building land and for sand and gravel.

6. An increase in leisure and affluence creating a demand for recreational land, such as golf courses.

FĂźll details of these changes were given in the publications mentioned above and will not be repeated. Suffice it to say that the area of heathland had been gradually (but fluctuatingly) declining for at least two centuries: it was reduced from about 7700 ha (19,000 acres) in 1889 to about 3000 ha in 1966; between 1949 and 1964 some 1200 ha (3000 acres) were reclaimed in the southern Sandlings alone.

Another important change followed the arrival of myxomatosis in Suffolk in December 1953 and the Virtual elimination of the rabbit population in the summer of 1954. Grazing of the heaths, already reduced by the disappearance of the sheep, virtually ceased. Already, by the late 1960s, invasion of the heathland by scrub and bracken was changing the character of the Sandlings landscape.

The reductions in the heathland area, and the associated changes were linked with a decline in the number of heathland organisms, and significant changes in the ecology of the heathland remnants.

An account of the developments in the land use of the region since about 1970 now follows.

Forestry Forestry remains one of the most important land uses in the Suffolk Sandlings: the Forestry Commission now (late 1982) occupies about 3075 ha (7500 acres); 2897 ha of this are under plantation: Table I gives an indication of the changes over the last 15 years. There has not been a major change in composition - conifers remain predominant (Table II) - but there have been changes of emphasis in the management of the holdings, partly as the result of the aging of the plantations. In the late 1960s, the m a j o r concern of the Commission was the thinning of the maturing stands, and with the occasional use of 'clear-fell and replant' techniques in stands that were found to be maturing unsatisfactorily. Much of the maritime pine (Pinus pinaster) and

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Suffolk Natural History, Vol. 20 Table I Plantation areas, Sandlings area (i. e. part Aldewood F (hectares) 1967 1981 5 Pre 1895 A 7 1896-1900 1901-1910 DU 1911-1920 38 1912-1930 1534 1242 557 1931-1940 778 1941-1950 242 144 1951-1960 542 449 1961-1970 93 237 1971-1980 195 1981 23 Uneven aged 32 To be planted 68 14 Non-forest land 149 164 3075 3597 -

-

-

Source: Forestry Commission District Office, Woodbridge: personal communication.

Notes: 1. The data are not strictly comparable, as Forestry Commission recording procedures changed between 1967 and 1981, and as can be seen from th totals, the area from which the data are available also differed.

2. The Forestry Commission began planting in 1920; the small areas shown as older than this, represent, in the main, pre-existing shelter belts.

poorer 'Ursuline' Corsican pine was felled; this amounted to a mean of approximately 20 ha per annum, and the cleared areas were replanted wi Corsican pine (Pinus nigra). From about 1976 onwards, however, substan parts of 'Aldewood Forest' (the Commission's name for its holdings in the region) were sufficiently matured for rotational felling to be planned. It was

Table II Species Composition: Aldewood Forest (approximate perce 1967

Scots pine Corsican pine Other conifers Broadleaved (oak, beech, poplar) Felled, awaiting replanting

%

%

44 41 3 7 5 100 100 Source: Forestry Commission District Office, Woodbridge: personal communication

Trans. Suffolk Nat. Soc. 20

45 40 5 10

1981

-

55

RECENT CHANGES IN LAND USE AND ECOLOGY

Table III Timberproduction: 1967 Sawlogs Pulp and boardmill material Pitwood Posts, stakes, rails Wood wood Firewood and misc.

Aldewood Forest, Suffolk % 32 36

18 6 2

6 100

1982 Special poles (e.g. Telegraph poles) Sawlogs Pulp, fibre, chip material Firewood and misc.

% 1 62 33 4

100 Source: Forestry Commission District Office, Woodbridge, Suffolk: personal communication.

expected that rotations of 50 years would be employed in the best stands of Corsican pine, and 65 year rotations would be found suitable for the poorest plantations of Scots pine (Pinus sylvestris). These plans were frustrated by extensive windthrow on the 2 and 3 January 1976. This felled some 30,000 cubic metres (1 million hoppus feet) of middle-aged to old pine, in a haphazard fashion throughout the forest, and much effort in the succeeding 18 m o n t h s had to be spent ' C l e a r i n g up the m e s s ' , and m a r k e t i n g the t i m b e r .

The 'clear-fell and replant' programme therefore restarted in earnest in 1978, with about 60 ha being cleared each year. The programme was revised in 1982, and Clearing is expected to increase to about 90 ha per annum in the short-term, decreasing towards the end of the Century. Thinning rates are to remain static. Corsican pine will be the main species used for replanting, although some 60 ha have been allowed to regenerate with Scots pine 'naturally': these areas were about two years old in 1982. The products have altered as management policies have changed: production is now running at 34,000 cubic metres per annum, and the composition is as shown in Table III. Perhaps unfortunately the forest workers' holding concept (whereby Forestry Commission employees were guaranteed work in the plantations for a certain fraction of the time, being free to work their holding for the remainder) has lapsed, although one parcel of land is still classed as such a holding. This system had the advantage of providing some ecological (and economic) variety in an otherwise rather homogenous environment, as well as constituting a link between the forests and nearby land uses. Forest work is now full-time and year-round.

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Agriculture The surge in the reclamation of heathland for arable agriculture which resulted in so much of the heath in the southern Sandlings being ploughed between 1949 and 1964 has abated. This has been stated as being partly because of the lack of profitability, but as a result of pressures from the conservation lobby. T h e r e are certain exceptions: part of Toby's Walks, near Walberswick was ploughed in 1971, and about 12 ha near Sailor's Path, Snape, has also come under the plough. In the latter case it was suggested to me that the reclamation was in part due to the ground being 'left in a disgusting State by the public'. Old bicycles, prams and iron bedsteads had been abandoned there, and heavy pressure by visitors constituted a fire-risk (see below).

Recreation Recreation pressure remains high on some areas of heathland. Table IV, showing traffic density as measured by an automatic traffic-counter on the B1387, near Blythburgh, East Suffolk, in the heart of the heathland district provides evidence of continuing visitor pressure on the area, although it does seem that the recent recession and high fuel prices have moderated this.

Littering and the abandonment of larger items of rubbish, including vehicles, remain problems, although I understand the provision of skips for bulky items of refuse in centres such as Ipswich, Southwold and elsewhere has eased the householder's difficulty of disposal of an unwanted bedstead or mattress! Fires on heaths continue to pose problems: Rushmere and Foxhall Heaths near Ipswich, particularly those parts covered with gorse (Ulex europaeus) are affected almost every year; heathland in the Walberswick area is burnt every three to four years and a very serious fire occurred in 1972.

Wenhaston is also regularly affected - there was a fire in September 1982. A t North W a r r e n the last m a j o r burning was in September 1970: at that time the conflagration burned for two days, and destroyed appreciable areas of bracken, grassland, gorse and a small reed-bed. A t Minsmere a small fire occurred on 14 April 1980, and although seven fire appliances were needed, and a fence was burnt, this was a mixed blessing: The Reserve Warden reported: The Scots pine and silver birch was badly damaged but this will probably prove helpful in that it will provide better nightjar habitat potential. The heather was burned right back. Not a bad thing as it was suffering from heather beetle very badly. The signs of regeneration are helpful.

(R.S.P.B, documents at Sandy Lodge.)

Fortunately, a little surprisingly, the region was relatively free from fires during the severe drought of 1976. T h e reasons for this may include the fact that the drought was slightly less severe close to the coast compared with inland: dew may have lowered the fire risk. Also a system of careful wardening was used to draw the attention of recreationists to the dangers.

And restrictions were placed on access via footpaths in some areas: this

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RECENT C H A N G E S IN L A N D USE A N D ECOLOGY

59

policy had no basis in law, but was apparently accepted by the public. No heathland reserves were badly burnt in that year.

The southward expansion of the Kessingland Holiday Camp was compared with 'a sinister oil-slick' (D. R. Moore, 1981), and it was asserted that 'campers were encouraged to go out and pick wildflowers and then enter their drooping posies in a "Wild Flower Competition"'.

Minor acts of vandalism have been reported - for example a damaged padlock on a Royal Society for the Protection of Birds (R.S.P.B.) reserve in 1978. Horseriders and uncontrolled dogs from time to time occasion damage or wildlife disturbance. Despite many decades of Publicity by conservation organisations such as the R.S.P.B., egging and the capture of birds for 'the fancy' remain problems.

Urban and related development Although the designation of Ipswich as an 'expansion town' in the late 1960s did not proceed, there has occurred the development of a new village, partly on former heathland, at Martlesham: 240 ha of land is involved. There has also been industrial development at Nacton and gravel working at Kesgrave.

Under this heading I should perhaps mention the proposal of the Central Electricity Generating Board to build a second nuclear power Station in the heart of the area - Sizewell B - at a cost of about ÂŁ1000 million.

Planning and Conservation strategy One of the conclusions of my 1960s investigation was that a continuation of the deterioration in the conservation status and ecological diversity of the heaths could be expected in the face of the 'piecemeal' approach to land management that had developed. Whereas heathlands had, until just after the First World War, been a component of a tightly integrated land use system, with the abandonment of sheep husbandry, links between the heaths and other nearby ecosystems had withered. The ownership of the freehold of some of the heaths had changed, and nearby landowners, conservation agencies and Government departments were prosecuting policies that were sometimes at odds with one another. Two developments, therefore, are to be particularly welcomed: the publication of the Suffolk Heritage Coast Plan in November 1978, amended in March 1982, and the formation of the Sandlings Group in 1980.

The Heritage Coast concept was given the imprimeur of Her Majesty's Government in an official circular from the Department of the Environment (12/72) in 1972. This supported the designation of stretches of coast of high scenic quality as Heritage Coasts as the result of joint action between the Countryside Commission and local authorities. The thrust of such an enterprise is to be four-fold: land use planning, conservation, management and interpretation. A pilot scheme for the coast from Kessingland to Felixstowe was inaugurated in January 1974, which aimed to identify and resolve conflicts of interest between those living on or managing the coast, those who visited the area for their recreation and the requirements of landscape and

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nature conservation. As the result of this experiment it was hoped that firm policies might be developed for inclusion in a Heritage Coast Plan. The Plan itself was produced in 1978 (May, 1978), by Suffolk County Council, but with the active co-operation of the Suffolk Coastal District Council and the Waveney District Council. Besides identifying the parts of the region subjected to the greatest recreational pressure and other damage, the report listed a number of most constructive suggestions for landscape improvement and amenity. These included the improvement of footpaths, the elimination of eyesores, tree planting, rationalisation of car parking, and the erection of interpretive signs. The programme is being implemented, and a further Programme of Works for the period 1982-1985 and beyond was produced in March 1982 (Barritt, 1982).

The Sandlings Group was formed in 1980 as an ad hoc committee with a particular interest in the management of the Sandlings heaths. It has representation from the Suffolk County Council, Suffolk Coastal District Council, the Suffolk Trust for Nature Conservation, the Royal Society for the Protection of Birds and the Nature Conservancy Council, all of whom are directly or indirectly responsible for substantial areas of heathland. An early task of the Group was the careful mapping of the Vegetation communities on the remaining areas of heathland in the district. It is to be hoped that co-operation in the management of the coastal heaths will be possible.

Experiments in heath land management Amongst the most pressing problems in the management of the heaths that once occupied thousands of hectares in East Suffolk is the rapid invasion of grass and heather (Calluna vulgaris and Erica cinerea) communities by bracken (Pteridium aquilinim), self-sown pine from nearby plantations, and a variety of other scrub species including eider (Sambucus nigra) and birch (Betula pendula) which are locally well established (e.g. in the Walberswick and Blythburgh areas).

The pressure that maintained the open character of the Sandlings heaths for generations was grazing (Armstrong, 1971, 1973) and it is interesting to note that this has been re-established on an experimental scale. Forty ha (100 acres) have been fenced for sheep grazing at Westwood Lodge near Walberswick. Preliminary results of the experiments suggest that it represents a useful technique on acid grassland, but is less suitable for other plant communities. Experimental enclosures for the investigation of the differences between the effects of sheep and rabbit grazing have also been established on the Walberswick National Nature Reserve (N.N.R.), as well as, since July 1979, on the R.S.P.B, reserve at North Warren.

Another useful experiment on the Walberswick N.N.R. has been, in the last few years, the use of a forage harvester to remove the bracken litter: this has been done, with permission, by a local nurseryman to obtain litter for growing azaleas. In places the action of the harvester has been sufficiently vigorous to allow heather seedlings to germinate.

More conventional types of cutting have been used locally - for example in the clearance of scrub and the elimination of invading pine saplings. Job-

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c r e a t i o n schemes, f u n d e d b y the M a n p o w e r Services C o m m i s s i o n , and C o m m u n i t y E n t e r p r i s e Programmes p r o v i d e d l a b o u r f o r some of this activi t y . ( T h e l a b o u r factor is i m p o r t a n t as some of the sapling c o n t r o l can o n l y p r o p e r l y be d o n e b y hand: o n 29 M a r c h 1980 some 1500 pine trees were r e m o v e d f r o m the heather at M i n s m e r e ( R . S . P . B , documents at Sandy).) A t N o r t h W a r r e n a 15-year cycle o f h e a t h l a n d c u t t i n g has been established; the c u t t i n g is n o r m a l l y done d u r i n g the p e r i o d January t o M a r c h .

A n e x p e r i m e n t a l c o n t r o l l e d b u r n i n g p r o g r a m m e has been c a r r i e d out at the W e s t l e t o n H e a t h N . N . R . since the 1960s. Since a 20-year r o t a t i o n has been devised, it w i l l be a few years b e f o r e the effectiveness of this can be f u l l y assessed. T h e reason f o r this is that some stands o f heather at W e s t l e t o n were e x t r e m e l y aged a n d 'leggy'. W h e n these plants are b u r n t , great heat is generated, a n d it may be five years before heather g r o w t h recovers. I t w i l l not be u n t i l w e l l i n t o the second cycle of r o t a t i o n that the benefits o f the e x p e r i m e n t w i l l become a p p a r e n t . T h e Situation is a c o m p l e x o n e , as some scientists argue t h a t the existence o f some heather 30 years o l d , o r even m o r e , i n a h e a t h l a n d C o m m u n i t y , is an advantage as i t c o n t r i b u t e s t o the diversity o f insects. C e r t a i n l y ecological precepts w o u l d suggest that the maintenance o f a mosaic o f p l a n t c o m m u n i t i e s - stands o f d i f f e r e n t species and o f v a r y i n g ages - s h o u l d c o n t r i b u t e t o the stability of the system. T h e p r e l i m i n a r y impression of some o f those i n v o l v e d i n Sandlings h e a t h l a n d m a n a g e m e n t is that there is n o t a great deal t o choose between c u t t i n g and b u r n i n g as m a n a g e m e n t techniques f o r ericaceous heathland. A recent i n n o v a t i o n has been the use o f chemical sprays as g r o w t h retardants t o i m p e d e b r a c k e n invasion. T h e herbicide asulam has recently been f o u n d e x t r e m e l y efficacious, r e d u c i n g b r a c k e n f r o n d density by 9 6 % , f r o n d height by 8 5 % a n d t h e Standing c r o p by 9 9 % ( M a r r s & L o w d a y , 1980). I t has been used since a b o u t 1978 by the R . S . P . B , at N o r t h W a r r e n : spraying i s i n J u l y o r A u g u s t . Several herbicides have also recently been m a r k e t e d f o r scrub c o n t r o l : some o f t h e m have disadvantages i n that they are slow-acting or d a m a g i n g t o c e r t a i n h e a t h l a n d species. I t is p r o b a b l e that ' K r e n i t e ' , a brush c o n t r o l agent m a r k e t e d by d u P o n t , w i l l eventually p r o v e the most satisfact o r y f o r b i r c h scrub c o n t r o l f o r conservation purposes i n English l o w l a n d heath e n v i r o n m e n t s , f o l l o w e d by t r i c h l o r p y r . 2,4,5 - T (sometimes m i x e d w i t h 2,4 - D ) has been suggested b u t its t o x i c i t y , together w i t h difficulties alleged t o be associated w i t h its d i o x i n i m p u r i t i e s render its use controversial.

Use o f these c h e m i c a l technqiues i n the management o f Sandlings heaths is in its earliest stages, b u t they are being considered i n a j o i n t research Programme o f the I n s t i t u t e o f T e r r e s t r i a l E c o l o g y and the N a t u r e Conservancy C o u n c i l ( M a r r s & L o w d a y , 1980).

H e r b i c i d e s m a y be e m p l o y e d t o k i l l scrub, b u t t o m a i n t a i n the a t t r a c t i v e , o p e n character o f h e a t h l a n d , dead stumps have t o be r e m o v e d . A n alternat i v e is f o r the scrub t o be cut first, and t h e n herbicide a p p l i e d t o cut stumps t o p r e v e n t r e g r o w t h . T h i s last is especially necessary w i t h b i r c h ; pine seldom regenerates f r o m cut stumps, a n d so herbicide t r e a t m e n t is not necessary.

T h e damage caused t o h e a t h l a n d ecosystems by fires. w i l d l i f e disturbance, l i t t e r i n g a n d careless p a r k i n g has been briefly m e n t i o n e d above. T h e object i v e o f local a u t h o r i t i e s a n d conservation organisations alike has been t o

Trane. Suffolk

Nnt. Snc 20

Suffolk Natural History, Vol. 20 concentrate recreational pressure on to areas where provision can be made and to discourage access and trespassing elsewhere. To quote an example: Toby's Walks, an area of heathland, scrub and old gravel workings nea Blythburgh, a limited area of parking has been provided, along with rusti picnic tables andfirebrooms.A toilet block has been built, and an interpre tive sign explains the origin of local place-names, the Heritage Coast concept, and something of the natural history of the area. The sign is one 40 erected in January 1979 as part of the Heritage Coast Scheme. Vehicula access to this and other nearby reserves (other than at designated car parks is discouraged by barriers and ditches.

Of course many of the recreationists visiting the area are birdwatchers and other categories of amateurfield-scientist.Special consideration is afforded them - for example through the provision of nature trails and special facilities for school visits. A nature trail opened at North Warren in 1978: 17 schoo visited the reserve in June and July of that year. One can expect many these visitors to be alert to the conservation value and amenities of the Sandlings region, but exceptions exist. A singlefigurewill indicate the magnitude of the problem: in 198129,602 visitors visited the R.S.P.B, nature reserve at Minsmere; this represented an increase of 19% on 1980, and followed the publicity given to the reserve in a BBC 'Birdwatch' TV Programme (R.S.P.B, documents at Sandy Lodge), see Figure 1.

Rabbits, although present in far lower numbers than before the advent o myxomatosis, and notwithstanding their contribution towards the maintenance of the open character of the heaths, are regarded as pests both by t Forestry Commission and farmers with land adjoining the heaths, and have to be controlled. For example, the R.S.P.B., since their purchase of the freehold of the Minsmere Reserve (formerly leased to them) in 1977, no

62

30 OOO-i

w ol 5 20 000 o

0) -O E 10 000

o

1974

1975

1976

1977

1978 1979 1980 1981 Years Fig. 1 Numbers of visitors to Minsmere Reserve (R.S.P.B.)

Trans. Suffolk Nai. Soc. 20

63 longer allow the shooting of rabbits, but do allow some trapping and ferreting, and at North Warren 293 were caught in this way in 1978-1979, and 165 in 1979-1980. Gassing with a Cyanide Compound is also practised.

RECENT CHANGES IN LAND USE AND ECOLOGY

Ecological changes The changes in the heathlands, and in their environment, mentioned above, have had a considerable effect on the ecology of the region. The complex, interconnected nature of ecosystems makes it difficult to discuss these succinctly, but a few brief examples will be followed by notes on the changes that have occurred in the status of a number of indicator organisms, that provide clues as to the 'ecological viability' of the heathland ecosystem as a whole. This was the approach used at the time of my earlier Sandlings study (Armstrong, 1970-1975) and has also been used in investigations of similar communities elsewhere, for example, by Moore (1962), in his study of the Dorset heaths.

Significant changes have occurred with the maturing of the conifer plantations. Immediately after the planting of heathlands with young conifers, and for some years, the essential character of the heath remains, but as the Minsmere Reserve Warden reported in 1976: Nightjars, as with tree pipits, will breed in young pine plantations for a number of years, but when the trees attain some height, and thefieldlayer becomes dense, they will cease to breed. (R.S.P.B, documents at Sandy Lodge.)

A number of heathland birds, reptiles, insects and plants are shaded out in this way. On the other hand the clear-felling of mature stands, which commenced recently, opens up the sombre plantations for the reestablishment, at least temporarily, of heathland organisms (see the notes on the woodlark and tree pipit below). In general, however, the expansion of Single species conifer plantations has tended to impoverish the ecological variety of the region, although a mature pine forest may yield a rieh harvest of fungi. Fallow, red and muntjac deer live in the forests: the Commission's district officer reported numbers 'static' in May 1982.

Other changes in status that may or may not be linked with land use changes include the decline in the red squirrel (now unfortunately subject to virus disease) and the increase in the grey. Mink, originally released from fĂźr farms have locally become a menace on some heathland reserves. R.S.P.B, records show that six young nightjars were destroyed by mink at Minsmere in 1979.

The nightjar, however, also provides an example of how careful management of the heathland environment may have been successful. The 1979 Minsmere report described the method of thinning out silver birch scrub on heathland, by cutting off the trees at ground level and then chemically treating the stumps (see above), and continued: The success of the nightjar management undertaken in 1978 exceeded all expectations during the 1979 breeding season - this type of management of Trans. Suffolk Nat. Soc. 20

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Suffolk Natural History, Vol. 20 lowland heathland for nightjars does work. In all . . . three pairs of nightjars used five managed nest sites. In Compartment 15, where work is still continuing, opening up an area of 30 year old birches, heather is already starting regrowth, and a pair of nightjars, which held territories several hundred metres to the north use it as a feeding area. (R.S.P.B, documents at Sandy Lodge.)

Contamination by pesticides continues to be a possible factor influencing the abundance of heathland organisms. An unhatched red-backed shrike's egg was found in the 1960s to contain chlordane. The decline of many species of heathland butterflies has similarly been blamed on 'chemical sprays' sometimes, however, on rather meagre analytical evidence. Birds of prey, the end members of food-chains, were especially hard hit in the 1950s and 1960s, in both heathland and farmland regions. Pearson (1973), writing of the Walberswick area reported a decline in the Kestrel to 'only two known pairs in 1963-1964. Thereafter increased to the numbers of the late 1950s'.

The improvement in the numbers of this and other species may be due to the placing of restrictions on the use of some of the more persistent pesticides in the later 1960s.

The data, including the graphs that follow, are based on a number of sources, including published reports in Suffolk Natural History, Suffolk Birds, R.S.P.B, and Nature Conservancy Council records, and personal enquiries.

Stone curlew (Burhinus oedicnemus). This bird was quite a common breeding species 'in every coastal parish' until 1956. By 1968 only 8 pairs were nesting on the coast, and this total had fallen to 4 in 1976. 'A distinct improvement' - to 7 pairs - was noted in 1975, but by 1977 the number of pairs breeding in Sandlings parishes had again fallen to 3. The same figure was noted for 1980, with the annotation 'As usual the number of breeding records is obviously incomplete' ( S u f f o l k Birds). Maybe this comment will prove to have been unduly optimistic, for the 1981 report declares only that 'Singles were noted at 4 coastal sites'. I was informed in the late summer of 1982 that two pairs were nesting in farmland areas.

Nightjar (Caprimulgus europaeus). A decline had already been noticed by 1967, but as late as 1969 at least 34 pairs were noted in the heathland belt.

Numbers were described as 'low and probably decreasing' in 1970, but the species' status was described as 'static' in 1973. A 'slight further decline' was reported in 1974, and in 1977 it was stated that there were only 9 + pairs along the coastal belt. Numbers recorded were 20 in each of 1979 and 1980, so it may be that the Statement in Suffolk Birds in 1977 that the species was 'grossly under recorded' was accurate. The 1981 report quotes the British Trust for Ornithology census (see Berry, 1979) of the species as recording 34 churring males in the coastal heathland zone: 'These figures are far beyond any recent estimate, and show how the breeding population of a specialist and retiring species can be misrepresented without a thorough census'. I was informed that in 1982,20 pairs were breeding on the coastal heaths. (See the notes above on efforts being made to improve heathland habitats for this species and Figure 2.)

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RECENT CHANGES IN LAND USE AND ECOLOGY

65

\Tree pipit

Nightjar''•••..

'Stonechat

1975

1976

1977

1978 1979 1980 1981 Years Fig. 2 Numbers of nesting pairs of tree pipits, nightjars and stonechats at Minsmere Reserve (R.S.P.B.)

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Suffolk Natural History, Vol. 20 Woodlark (Lullula arborea). There is some evidence that this species making a 'comeback'. The following extracts from the Suffolk Bird Reports (in Suffolk Natural History and Suffolk Birds) teil the story: 1967 Numbers continue low 1968 4 pairs 1969 (nodata) 1970 Perhaps a dozen 1971 5 sites in coastal belt; at two breeding took place 1974 4 places 1973 Numbers very low 1974 Breeding population very low; 6 singing birds in coastal area 1975 12 pairs in coastal belt 1976 Numbers very low 1977 3 areas near coast 1978 10 pairs at 3 sites, including a new area 1979 Species hopefully making a comeback 1980 Data obviously incomplete: 10 pairs from 6 sites on coast 1981 In all (of Suffolk) 20 pairs were reported, but it is anticipated that this only represents a part of the total population.

It is likely that the species has benefited from Forestry Commission clearfelling.

Tree Pipit (Anthus trivialis). The pattern seems to be very similar to that the woodlark, and similar factors are probably at work; afforestation tends to destroy suitable habitats, but recent felling has provided open areas with scattered trees. The following extracts summarise the position: 1968 Appears to be declining everywhere 1969 Small and declining numbers 1970 Very much down in numbers 1971 Status now rather uncertain . . . numbers probably rather low . . . rapidly declining (Very few records for the mid-1970s.)

1977 Scattered records from coast; probably very much under recorded.

1978 Breeding sparsely in coastal belt 1979 32 singing males in the whole county 1980 Breeding probably grossly under-recorded 1981 Up to 45 pairs in the breeding season ... (in the whole county) . . numbers. . . increasing.

Stonechat (Saxicola torquata). This species has been remarkably constan through the last 15 years, but there has been some evidence of a recent increase.

Whinchat (Saxicola rubetra). This species seems to have virtually disappeared from the coastal heaths. Numbers were consistently described as 'low' throughout the late 1960s and early 1970s. In 1977 it was said to have bred at 2 sites, there was a pair at Walberswick in 1978, but few, if any record since. There have been no Minsmere breeding records for about 10 years.

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RECENT CHANGES IN LAND USE AND ECO LOG Y

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Wheatear (Oenanthe oenanthe). Numbers on the Sandlings heaths have been low, but fluctuating. There does seem to have been a recovery in the late 1970s, and indeed the species nested at Minsmere in 1980 for the first time since 1967. The improvement may turn out to be short-lived. The wheatear is ecologically closely associated with the rabbit, utilising burrows for nesting, and requiring open, grazed areas for feeding. It may also have suffered more than other species with the decline of rabbit numbers through the deflection of food-chains, as ground-nesting species are vulnerable to mammalian predators.

Red-backed shrike (Lanius cristatas). This species was reported in 1967 to be 'continuing to decrease', but in 1969 24+ pairs were noted along the coast.

Throughout the 1970s 12-15 pairs were recorded on the coastal heaths in most years. This number increased to '27+' in 1977, but 'an unfortunate disastrous crash' followed in 1978, with only 15 pairs in the whole county.

Numbers have remained fairly low with 8 pairs on the coastal heaths in 1980.

In 1981 and 1982 very few pairs were proved to have bred. It last nested (a Single pair) at Minsmere in 1975. The species has almost gone as a Sandlings heathland species. This fact has to be considered in the context of its spectacular decline, both in numbers and its geographical ränge, over much of north-west Europe for over 50 years (Bibby, 1973). Although habitat destruction and pesticide contamination may be contributory factors, the trend is so universal and long-continued that climatic change has been cited as a possible explanation.

Adder (Vipera berus). Remains in appreciable numbers on Sandlings heaths. No evidence of recent decline. A reddish form of female was noted at Walberswick in July 1979.

Common lizard (Lacerta vivipara). As with the adder, widespread on the coastal heaths.

Natterjack toad ( B u f o calamita). Extinct in the Sandlings region for some years.

Emperor moth (Saturnia pavonia). Not common, but still occurs on Sandlings heaths.

Silver-studded blue (Plebius argus). In the immediate post-war period, this insect was recorded on many coastal heaths including those at Blythburgh, Foxhall, Martlesham, Purdis Heath, Wenhaston and Westleton, and although there appears to have been a decline, with sometimes several seasons passing without a record from some localities, the species does seem persistent. Although the casual reader of the annual reviews of Suffolk lepidoptera published in these pages in the 1970s might have been forgiven for believing the species was confined to one or two sites (e.g. Wenhaston), in 1979 it was reported that 'it had a good season in all its old habitats around Ipswich', and was 'also seen in one of its old haunts on East Hill, Walberswick'. And 'a flourishing colony' was discovered near Dunwich in 1973.

Separate populations may behave differently, for in 1971 'a search of the known habitat at Wenhaston on 22 July failed to reveal any' yet the butterfly 'was still quite plentiful on one of the heaths near Ipswich'. The species does seem to be holding its own.

Grayling (Eumenis semele). An erratic species, sometimes almost disTrans. Suffolk Nat. Soc. 20

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Suffolk Natural History, Vol. 20

appearing for several years. At Walberswick, in spite of the fire in 1972, reasonable numbers were recorded in 1973. In this area low numbers were recorded during the period 1976-1978, with a substantial increase in 1979 In 1982 this attractive and characteristic heathland butterfly was said to be 'increasing'.

Meadow brown (Maniola jurtina). Substantial recent increase.

Hedge brown (Maniola tithonus). Substantial recent increase.

Summary and conclusion Although pressures on the Sandling heaths, and also upon other land use categories in the region, remain high, the very abrupt decline in the area of heathland has ceased. New institutions and policies have come into being to assist in the conservation of the heaths, and a number of experiments in heathland management are in progress. Efferts are being made by local authorities and conservation organisations to harness the increasing interest in conservation and natural history constructively, and there is some evidence of increased awareness of amenity values by some landowners, local government officials and recreationists. Some characteristic heathland indicator organisms have declined in numbers and in their distributions; a few have disappeared from the region. Careful conservation measures are in Operation to protect some of the others, and a few have increased. Complacency must be avoided, but my own view is that the outlook is nothing like as pessimistic as 12-15 years ago.

Acknowledgements I am deeply indebted to the following (amongst others) for information and suggestions, freely given in letters or interviews: Mr. E. E. Barritt, County Planning Officer, Suffolk County Council; Mr. J. Crudass, Reserves Officer, Royal Society for the Protection of Birds, The Lodge, Sandy, Bedford; Mr. E. Harris, Divisional Agricultural Officer, Ministry of Agriculture; Mr. J. Kember-Smith, Highway Traffic Division, Transport and Road Research, Crowthorne, Berkshire; Mr. C. J. D. Shackles, Assistant Regional Officer, Nature Conservancy Council; Mr. H. Searle, Divisional Officer, Forestry Commission.

Associate Professor A. J. Conacher kindly read a draft of this article, and made a number of constructive comments.

References Armstrong, P. H. (1970). The Heathlands ofthe Suffolk Sandlings in Their Setting: a Systems Approach to Landscape Study, Ph.D. Thesis, C . N . A . A . , College of Arts and Technology, Cambridge.

Armstrong, P. H. (1971). The heathlands of the East Suffolk Sandlings, Trans. Suffolk Nat. Soc. 15, 417.

Armstrong, P. H. (1972). The Rabbit in East Anglia, East Anglian Magazine, 31, 162.

Armstrong, P. H. (1973). Changes in the land use o f t h e Suffolk Sandlings: a study of the disintegration of an ecosystem, Geography, 51,1.

Trans. Suffolk Nat. Soc. 20

69 Armstrong, P. H. (1974). Some examples of the use of current ecosystem models as frameworks for land use studies, Geowest, 3, (Occasional Papers of the Department of Geography, University of Western Australia).

Armstrong, P. H. (1975). The Changing Landscape, Lavenham, Terrence Dalton.

Barritt, E. E. (1982). Heritage Coast, Suffolk Coast and Heaths A. O.N Programme of Works, Suffolk County Council Planning Office, Memorandum.

Berry, R. (1979). Nightjar habitats and breeding in East Anelia, British Birds, 72, 207.

Bibby, C. J. (1973). The Red-backed Shrike - a vanishing British species Bird Study, 20,103.

Marrs, R. H. and Lowday, J. E. (1980). Bracken and Scrub Control on Lowland Heaths, Interim Report to Nature Conservancy Council on N.C.C./N.E.R.C. Contract HF 3/03/142, TE Project 599, Monks Wood, Huntingdon, Institute of Terrestrial Ecology.

Moore, D. R. (1981). Observationson theornithological,topographical and other changes of Benacre-Covehithe, 1968-1980, Suffolk Birds 1980.

Moore, N. W. (1962). The heaths of Dorset and their conservation. J. Ecol 50, 369.

Raynbird, H. (1849). The Agriculture of Suffolk, London.

Way, A. (1978). Suffolk Heritage Coast Plan, Ipswich, Suffolk County Council.

Young, A. (1795). Ann. Agric. 23,18.

RECENT CHANGES IN LAND USE AND ECOLOGY

Dr. P. H. Armstrong, Department of Geography University of Western Australia, Nedlands, Western Australia, 6009.

Rocky Mountain Sage, Lanceleaf or Mint-weed Salvia reflexa Hรถrnern. (= S. lanceolata Brouss.)

A small specimen of Salvia from a Stowmarket garden in 1976, at that time determined as S. triloba L. f., has now been identified by Mr. E. J. Clement as S. reflexa Hรถrnern. A native of North America, it occurs in Britain as a casual on rubbish tips, in arablefieldsand gardens from waste bird-seed.

First recorded in Britain at Fritton, Norfolk in 1928. The plant is now a troublesome weed in Australia and elsewhere and is poisonous to livestock.

This Suffolk record is believed to be the first for the County.

F. W. Simpson.

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