APPENDIX 15.6 DORMOUSE SURVEY

Transcription

1 APPENDIX 15.6 DORMOUSE SURVEY

2 Picket Piece - Dormouse Nut Search Report Wates Development Limited December Dormouse report

3 QM Issue/revision Issue 1 Revision 1 Revision 2 Revision 3 Remarks Draft for issue Revision For issue Date November 2009 November th December 2009 Prepared by Angela Bond Angela Bond Angela Bond Signature Checked by Liat Wicks Liat Wicks Liat Wicks Signature Authorised by Jo Gough Jo Gough Jo Gough Signature Project number File reference WSP Environment & Energy Mountbatten House Basing View Basingstoke Hampshire RG21 4HJ Tel: +44 (0) Fax: +44 (0)

4 Contents 1 Introduction 1 2 Methodology 2 3 Results 3 4 Discussion 4 5 Conclusions 6 References 7 Figure 1 Results of 2004 Survey 8 Figure 2 Results of 2009 Survey 9

5 1 Introduction 1.1 BACKGROUND A new residential development is proposed at Picket Piece, Andover. The development area includes hedgerows, grassland fields, residential gardens and a poultry farm. An extended Phase 1 habitat survey has been undertaken of the site by WSP Environmental Ltd (WSPE), to identify potential ecological constraints to development at the site, and further descriptions of the site can be found within the Phase 1 habitat report (WSPE, July 2009). Figure 1 shows the extent of the ecological survey area 1, hereafter referred to as the site During the extended Phase 1 habitat survey and the associated desk study, the potential for the site to support dormice was assessed to be low, primarily due to the absence of any connectivity between the site and any woodland habitat. Although some of the hedgerows on site were recognised as being outgrown and species rich, and therefore potentially suitable for dormouse; these are scattered across the site and appear to exist in isolation from any sizeable reserve of suitable habitat. A dormouse record was returned from Harewood Forest approximately 1km to the south-east of the site. This large block of ancient woodland habitat is not connected to the application site in any way, being separated by large agricultural fields without boundary hedgerows In September 2009 WSPE were made aware of a previous dormouse survey that had been undertaken on the site in 2004, this survey identified the presence of dormice in three separate parts of the site, as shown on Figure Due to the time of year (September), it was not possible to initiate a nest tube survey of the site. Such surveys should be started during April or May and the nest tubes inspected monthly until October or November, when the tubes can then be collected in. WSPE have therefore undertaken a nut search with the aim of determining whether dormice are still present on the site. 1.2 THE APPLICATION OF DORMOUSE NUT SEARCHES Dormice feed on hazel nuts in a very different way from other small rodents, meaning that it is possible to confidently identify hazel nuts that have been gnawed by dormice. Nut searches are therefore an excellent way of determining dormouse presence in areas where fruiting hazel is frequent (Natural England, 2006). However, information relating to abundance or range cannot be inferred from this type of survey. Neither can the survey be undertaken where hazel is absent. 1 Since the exact red-line application boundary had not been determined at the onset of the ecological field survey, an ecological survey area has been identified. This area represents the maximum extent of any potential application boundary at the site Dormouse report 1

6 2 Methodology The survey methods followed guidance within the dormouse conservation handbook (Natural England, 2006) as far as was possible. Although nut searches can be conducted year round, the optimal season for nut searches is between August (when hazels begin to fall) and December (before the nuts begin to degrade). The survey was undertaken on the 1 st October 2009, which is in the middle of the optimal season. Weather conditions were dry and sunny during the survey. The survey covered all areas of the site in which dormice had been recorded in The ground was searched beneath areas of fruiting hazel for the presence of nuts showing the characteristic signs of being gnawed by dormice. Each survey was undertaken for 20 minutes. If no dormouse nuts were found, the process was repeated in a different location until a total of five such areas had been searched The standard survey methods have been developed primarily for surveys in woodland, and as such the guidance suggests a search area of 10m x 10m for is adopted for each 20 minute search (Natural England, 2006). At Picket Piece, the fruiting hazel is located along hedgerows and is patchily distributed. It was therefore necessary for the size of the search areas to be defined by the areas of fruiting hazel, this meant that search areas were approximately 3x5m in size An additional measure of appropriate search effort for dormouse nuts can be undertaken by counting the total number of nuts gathered that show signs of being opened by small mammals of any kind (except squirrels). This total was recorded. 2 Research by Bright, Mitchell and Morris (1994) has shown that if five squares fail to yield dormouse nuts, it is about 90 per cent certain that dormice are not present Dormouse report 2

7 3 Results Two hazel nuts were found that had been opened by dormouse, thereby confirming that dormouse is present on the site. These were found along the railway line in the north of the site at Target Note (TN) 1, on Figure 2. There is a large amount of fruiting hazel along these hedgerows and a total of four 20 minute searches were conducted here (stopping when presence of dormouse was confirmed) A total of 111 hazel nuts were gathered that had been gnawed by a small mammal (excluding squirrels). This represents a suitable level of survey effort 3. Of these, 2 were positively confirmed as being gnawed by dormouse. The nuts in question were this year s crop, proving presence within the past few months. 104 were gnawed by mice or voles, and the remaining 5 were considered likely to have been gnawed by dormouse, but were more than a year old and therefore identification was not certain No fruiting hazel is present in the centre of the site (TN 2), and only a single, small hazel shrub is present in the south-east of the site (TN 3), under which only one hazel nut could be found. Therefore, it is not possible to confirm that dormice are currently present on these two parts of the site. 3 It is suggested in the dormouse conservation handbook that if 100 such nuts are gathered, and no nuts have been opened by dormice then there is a high probability that dormice are not present (W. Cresswell, pers. comm. In Natural England, 2006) Dormouse report 3

8 4 Discussion 4.1 EVALUATION Dormice are confirmed to be present along the railway line at the northern boundary of the site. It should therefore be assumed that this species occurs within all suitable habitat linked to this location (TN1, Figure 2) No assessment of presence can be made within the other two areas of the site (TN2 and TN3, Figure 2), since insufficient fruiting hazel is present. Therefore, no current presence or absence data are available for dormouse in these two areas. It is recommended that dormice are assumed to be present in these two locations, in keeping with the precautionary principle, The approximate size of suitable habitat in each of the three areas is as follows; Site location TN reference (see Figure 2) Approximate size (Ha) By Railway TN1 1 Centre of site TN2 0.6 South-east TN3 0.5 Total =2.1 hectares There is no obvious link between the three habitats on site, and it would seem unlikely that dormice can currently move freely between these three areas. The habitat at TN1 is connected to potentially suitable dormouse habitat along the London Exeter railway line and a small (5 hectare) copse to the north of the railway line (immediately north of Picket Piece). Approximately 4.7km east of Picket Piece the railway line does connect to Cowdown Copse, which is a circa 60 hectare woodland Current knowledge of dormouse ecology as set out within Natural England, (2006) suggests that individuals occur at a low density (an average of adults per hectare). Based on the upper end of this range, a hypothetical population of approximately 5 adults could be expected across the site. Even assuming these adults can travel between the three areas, this is still less than the 20 adults suggested as a minimum viable population (Natural England, 2006; 19). The long-term viability of the dormouse population on site therefore appears to be threatened Dormice are legally protected under European legislation due to their threatened conservation status. Their numbers and distributional range have declined by at least half during the past 100 years and this decline is thought to be continuing (Natural England, 2006; 9). In addition to direct habitat loss, dormice are particularly sensitive to habitat deterioration, fragmentation and inappropriate habitat management as well as weather and climate, and this makes them highly vulnerably to local extinction (Natural England, 2006; 9). 4.2 IMPLICATIONS FOR THE MASTERPLAN The existing habitat links between the three dormouse areas as identified in the 2004 survey are poor. The introduction of new development should seek to improve links if possible and enhance existing dormouse habitat. This could be achieved through new native hedgerow planting, augmentation of the existing hedgerows with native species that produce food for dormice (such as wayfaring tree, hazel, oak, and honeysuckle) and the adoption of a 3-5 year management regime that is on a rotational basis, to maximise the amount of food that is available to dormice at any one time, Prior to designing a detailed mitigation strategy for dormice, further information about the dormouse population on site should be obtained through monitoring surveys in 2010 (using nest boxes to monitor the population density) and the information obtained from the surveys should be used to inform future conservation efforts on the site. 4.3 LEGISLATION AND TRANSLOCATION Dormice are fully protected under the Habitat Regulations (1994) and the Wildlife and Countryside Act, (1981). This means that they are protected against killing, injury and disturbance, and their habitat is protected against damage or destruction Dormouse report 4

9 4.3.2 A European Protected Species (EPS) licence will be required in order to implement parts of the site clearance phases of any development of Picket Piece (specifically to undertake translocation of dormice or clearance within the areas that support dormice). Natural England are the licensing body and they will grant licences to deviate from the legislation, provided that it can be demonstrated that there is a) an imperative reasons of overriding public or economic interest to do so, and b) the conservation status of the dormouse population will be maintain (or enhanced). A dormouse mitigation strategy should be developed, describing all of the measures that will be adopted with respect to the conservation of dormice. This normally takes the form of a Method Statement which can then be submitted to Natural England alongside the licence application Furthermore, in order to grant planning permission for a site that will impact upon an EPS, the local authority must also be satisfied of these two criteria. Therefore, it will be necessary to ensure that these two conditions are addressed within the planning submission Once construction activity has begun in areas that affect the dormouse habitat (i.e. those areas for which an EPS licence will be required), monitoring surveys should be undertaken periodically throughout the construction and early operational phases of the development, to identify whether mitigation measures have been successful and to allow the mitigation and management measures to be adapted in response to the monitoring results, if necessary Dormouse report 5

10 5 Conclusions Previous surveys undertaken in 2004 have identified presence of dormice within hedgerows at 3 separate locations on site The findings of the 2009 nut search confirmed that dormice are still present within one of these locations (along the northern boundary with the railway line). The 2009 nut search technique was not applicable to the other two areas of potential dormouse habitat due to a lack of hazel nuts. Therefore, no current presence or absence data are available for dormouse in these two areas Following the precautionary principle, it is recommended that dormice are assumed present at all three locations in which they have been previously recorded The dormouse habitat across the site is small and fragmented and the long-term viability of the dormouse population on site therefore appears to be threatened, even in the absence of development The landscape strategy for the new development should seek to retain existing dormouse habitat and improve the connectivity and suitability of the habitat for dormice. This could be achieved by new native hedgerow planting and a sympathetic management regime Dormice are a European Protected Species. In order to grant planning permission for a site that will impact upon dormice, the local authority and Natural England must also be satisfied that there is a) an imperative reason of overriding public or economic interest, and b) the conservation status of the dormouse population will be maintain (or enhanced) A dormouse mitigation strategy will therefore be required at the reserved matters stage to describe what provisions will be put in place for dormice. This should be approved by Natural England prior to submission and is likely to involve the retention and expansion of dormouse habitat in a dedicated region of the site, followed by translocation of dormice into the dedicated area Dormouse report 6

11 References Bright, Mitchell and Morris (1994) Dormouse distribution: survey techniques, insular ecology and selection of sites for conservation. Journal of Applied Ecology. 31: Natural England (2006) The Dormouse Conservation Handbook. Paul Bright, Pat Morris and Tony Mitchell-Jones. WSP Environmental (July 2009) Picket Piece Phase 1 habitat Survey WSP Environmental (November 2009) Picket Piece Hedgerow Report Dormouse report 7

12 Figure 1 Results of 2004 Survey Dormouse report 8

13 Results of 2004 Dormouse Survey Figure 1 Key Ecological Survey Area Dormouse Distribution Reproduced from the Ordnance Survey maps with the permission of the Controller of Her Majesty's Stationery Office Crown Copyright WSP Environmental Ltd Licence No. AL PROJECT: PROJECT No: CLIENT: Picket Piece, Andover Wates Development Ltd DRAWN: GH CHECKED: AB APPROVED: CR REVISION: A DATE: December 2009

14 Figure 2 Results of 2009 Survey Dormouse report 9

15 Results of 2009 Dormouse Survey Figure 2 Key Ecological Survey Area Suitable Dormouse Habitat Target Note (Refer to text within the report) TN1 TN3 TN2 Reproduced from the Ordnance Survey maps with the permission of the Controller of Her Majesty's Stationery Office Crown Copyright WSP Environmental Ltd Licence No. AL PROJECT: PROJECT No: CLIENT: Picket Piece, Andover Wates Development Ltd DRAWN: GH CHECKED: AB APPROVED: CR REVISION: A DATE: December 2009