The editorial feature ‘Quality counts’, in White Admiral 49, referred to the current and ongoing Suffolk Parish Hedgerow Survey, which aims to provide a detailed and accurate picture of the county’s hedges in terms of form (overgrown, well managed, laid etc) and the woody species (trees and shrubs) they contain. Data collected in the survey, which is to be analysed at the Suffolk Biological Records Centre, will provide an up to date baseline measurement for the amount of hedgerow in the county, as well as the number or length of hedgerows, which are ancient and / or species rich – information that is vital for their conservation (Suffolk Biodiversity Action Plan, 1998).
Countywide support is being given to this project by The Suffolk Coastal Greenprint Forum, a partnership between a wide range of organisations, business and interest groups, all with a concern for environmental issues. The SWT, RSPB, FWAG, and English Nature also support the project. The project is organised by the Hedgerow Subgroup of the Greenprint Forum, who report that, to date, over sixty parishes are taking part.
The Bentley Parish Hedgerow Survey, which is part of this project, was started in 2001. Twenty-eight volunteers were involved and by the end of the year 20% of the field/hedgerow boundaries had been completed. It is anticipated that a further 20% will have been completed by the end of 2002.
In September 2002, a variety of hedgerows in Bentley, from well managed to overgrown and species-poor to species-rich, were also surveyed for dormice Muscardinus avellanarius. Suffolk is on the edge of the dormouse’s range and they have never been common in the county. There is an isolated population in Bradfield Woods but dormice are thought to be largely confined to South Suffolk, particularly on the border with Essex (Suffolk Biodiversity Action Plan, 1998). They are known to be present in several of the Bentley woodlands. Dormice are closely associated with ancient semi-natural woodlands but they do occur in hedgerows provided that these meet the specialized needs of this resident mammal. In a Mammal Society Dormouse Survey (Hurrell and McIntosh, 1984) 16% of the records were from hedgerows. Surveys in Kent (P.A. Morris and P. Mitchell, unpublished data) and Somerset (P.W. Bright and P.A. Morris, unpublished data) found evidence of dormice in many species-rich hedgerows.
To determine whether dormice in Bentley are using any of the hedgerows and, if so, which types, Tammy Gray, a student at Wye (Imperial College, University of London) placed dormouse nest tubes in selected hedgerows during July and returned to examine them in September. Predictions suggested that if dormice were found they would be in unmanaged, species-rich hedgerows, especially if these contained the animals’ favoured food plants – honeysuckle Lonicera periclymenum (nectar), bramble Rubus fruticosus agg. (berries) and hazel Corylus avellana (nuts), and not in hedges that were over managed or species-poor.
This turned out to be the case. Dormice, and evidence of dormice in the form of 13 their nests were found in several hedgerows, all of which were overgrown, speciesrich and contained the favoured food plants. There was no evidence of dormice using over managed or species-poor hedges. Dormice and dormouse nests of woven grass were present in several tetrads, both in the north of the parish (TM1038) and in the south (TM1036). They were also found just outside the Bentley parish boundary in East Bergholt (TM0834).
The Common or Hazel Dormouse, as it is sometimes known, has suffered a dramatic decline over the past century. Evidence indicates that it has disappeared from about half its geographical range in Britain (Bright and Morris, 1996). In Suffolk, it seems to have declined recently (Roughton, 1988), ‘suggesting that a range contraction may be in progress in East Anglia’ (Bright and Morris, 1996).
Fragmentation, deterioration and loss of specialized habitat, including hedgerows, have played a major part in bringing about the decline. Like ancient woodland, hedgerows in Britain have been severely depleted – a quarter (126,000 miles) have been lost to intensive agriculture since 1945 (Hawes, 1994); additionally, many of those which remain are over managed or species-poor and quite unsuitable for dormice.
In Bentley, the next step is to find out exactly where dormice still occur in other hedgerows, so that all such sites can be protected. Equally important we need to know about areas where dormice are absent from potentially suitable hedgerows, so that their management can be improved for the benefit of these small, attractive, nocturnal mammals.
The Common Dormouse is listed on Schedule 6 of the Wildlife and Countryside Act, 1981. It was granted full protection as a Schedule 5 species in 1986. It was targeted as a major component of English Nature’s ‘Species Recovery Programme’ in 1992.
Bright, P.W. & Morris, P.A. (1996). Why are Dormice rare? A case study in conservation biology. Mammal Review, 26, 157-187. Mammal Society.
Bright, P.W. & Morris, P.A. Unpublished data: In Bright, P.W. & Morris, P.A. (1996).
Hawes, C.J. (1994). Hedging again – a new Government measure. White Admiral, 28, 1-2.
Suffolk Naturalists’ Society.
Hawes, C.J. (2001). Quality counts. White Admiral, 49, 1-2. Suffolk Naturalists’ Society.
Hurrell, E. & McIntosh, G. (1984). Mammal Society Dormouse Survey, January 1975- April 1979. Mammal Review, 14, 1-18.
Mitchell-Jones, A. (2001). The Great Nut Hunt 1993. Mammals UK. Summer 2001.
People’s Trust for Endangered Species.
Morris, P.A. & Mitchell, P. Unpublished data: In Bright, P.W. & Morris, P.A. (1996).
Roughton, J. C. (1988). Suffolk Dormouse Survey. Unpublished Report for Suffolk Wildlife Trust.
Sanderson, F. (2002). Dormice and Climate Change. Mammals UK. Spring 2002. People’s Trust for Endangered Species.
Suffolk Biodiversity Working Group. (1998). Suffolk Local Biodiversity Action Plan.
Woodroffe, G.L. (2002). Wildlife Reports: Mammals. British Wildlife, 13, 428.
I wish to thank Dr Simone Bullion for putting me in touch with Tammy Gray and suggesting that the Bentley Parish Hedgerow Survey could be linked with the hedgerow search for dormice. I thank her, too, for providing a copy of the paper written by Bright & Morris (1996). I am indebted also to Tammy Gray for inviting me to take part in her survey.
Colin Hawes
Bentley Parish Hedgerow Survey Co-ordinator
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