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A review of horseshoe bats flight lines and feeding areas.

G. Billington & M.D Rawlinson

CCW Science Report No. 755

© CCGC/CCW 2006

You may reproduce this document free of charge for non-commercial and internal business purposes in any format or medium, provided that you do so accurately, acknowledging both the source and Countryside Council for Wales's copyright, and do not use it in a misleading context.

This is a report of research commissioned by the Countryside Council for Wales. However, the views and recommendations presented in this report are not necessarily those of the Council and should, therefore, not be attributed to the Countryside Council for Wales.

Report series: CCW Science Report

Report number: No. 755

Publication date: September 2006

Contract number: FC 73-01-406

Contractor: Greena Ecological Consultancy

Contract Manager: Liz Halliwell

Title: A review of horseshoe bat flight lines and feeding areas

Author(s): G. Billington, M.D Rawlinson Restrictions: None

Distribution list (core): CCW HQ Library, Bangor CCW North Region Library, Mold CCW North Region Library, Bangor CCW S&E Region Library, Cardiff CCW S&E Region Library, Llandrindod CCW West Region Library, Aberystwyth

National Library of Wales British Library Welsh Assembly Government Library Joint Nature Conservation Committee Library Scottish Natural Heritage Library Natural England Library

Distribution list (others): Jane Garner, CCW South & East Wales Region Steve Lucas, West Wales Region Matthew Ellis, CCW North Wales Region Liz Halliwell/Jean Matthews – HQ Clive Hurford - HQ Tony Mitchell-Jones, EN Jessa Battersby, JNCC David Bullock - National Trust

Richard Dodd, Bat Conservation Trust Vincent Wildlife Trust Peter Smith Peter Andrews Geoff Billington Bob Stebbings

Recommended citation for this volume: Billington, G., Rawlinson, M.D. 2006. A Review of horseshoe bat flight lines and foraging areas. CCW Science Report No: 755, 23pp, CCW, Bangor.

CCW Natural Science Report No. 755

CONTENTS CONTENTS __________________________________________________________________i

CRYNODEB GWEITHREDOL _________________________________________________ ii

EXECUTIVE SUMMARY______________________________________________________iii

1 Introduction _____________________________________________________________ 4

1.1 Evolution/ Ecology_______________________________________________________ 4 1.1.1 Greater horseshoe bats _________________________________________________ 4 1.1.2 Lesser horseshoe bats__________________________________________________ 5 1.1.3 Flight morphology ____________________________________________________ 5

1.2 Roosting Ecology ________________________________________________________ 6

1.3 Key threats to bats_______________________________________________________ 8

1.4 Legislation _____________________________________________________________ 8 1.4.1 The Bern Convention __________________________________________________ 8 1.4.2 1981 Wildlife and Countryside Act _______________________________________ 8 1.4.3 The Habitats Directive _________________________________________________ 8

1.5 Guidelines for the selection and notification of Bat SSSIs and SACs _____________ 9

1.6 Relationship of SACs to SSSIs ____________________________________________ 10

2 Aims __________________________________________________________________ 10

3 Methods________________________________________________________________ 10

4 Results_________________________________________________________________ 11

4.1 Habitat fragmentation _______________________________________________ 11

4.2 Hedgerows ____________________________________________________________ 12

4.3 Topography ___________________________________________________________ 13

4.4 Foraging ______________________________________________________________ 13 4.4.1 Lesser horseshoe bats_________________________________________________ 13 4.4.2 Greater horseshoe bats ________________________________________________ 14

4.5 Artificial lighting _______________________________________________________ 16

4.6 Climate _______________________________________________________________ 16

4.7 Insecticides and Pesticides _______________________________________________ 16

5 Discussion______________________________________________________________ 17

6 Acknowledgements _________________________________________________________ 19

7 References ________________________________________________________________ 20

APPENDIX: Guidance for the identification/ management of horseshoe flight lines and foraging areas_______________________________________________________________ 23

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CRYNODEB GWEITHREDOL Mae’r prosiect yma’n ymwneud â phennu canllawiau ar gyfer staff y Cyngor Cefn Gwlad o ran adnabod ffiniau llwybrau hedfan ystlumod a’r mannau a ddefnyddir gan ystlumod pedol mwyaf ac ystlumod pedol lleiaf (Rhinolophus ferrumequinum a Rhinolophus hipposideros) i chwilio am fwyd. Caiff yr wybodaeth yma ei defnyddio wrth ystyried hysbysu ac ymestyn Safleoedd o Ddiddordeb Gwyddonol Arbennig (SoDdGA) ac Ardaloedd Cadwraeth Arbennig (ACA) yn y dyfodol. O fewn y DU, caiff ystlumod pedol mwyaf ac ystlumod pedol lleiaf eu gwarchod dan Gytundeb Bern, Deddf Bywyd Gwyllt a Chefn Gwlad 1981 a Rheoliadau Cadwraeth (Cynefinoedd Naturiol ac ati) 1994, sy’n rhoi Cyfarwyddeb 92/43/EEC ar waith er mwyn nodi nifer o fesurau ar gyfer diogelu’r rhywogaethau a restrir yn Atodiad II. Mae’r Atodiad yma’n cynnwys yr ystlum pedol mwyaf a’r ystlum pedol lleiaf, yn ogystal â’r ystlum du, y daethpwyd o hyd yn ddiweddar i’r gytref fagu gyntaf o’i bath y gwyddys amdani yng Nghymru (Billington 2001d). Mae gofynion y Rheoliadau’n cynnwys dewis, dynodi a gwarchod rhwydwaith o safleoedd a adnabyddir fel Ardaloedd Cadwraeth Arbennig (ACA). Mae’r rhan fwyaf o’r safleoedd yma wedi eu hysbysu eisoes fel Safleoedd o Ddiddordeb Gwyddonol Arbennig (SoDdGA). Sefydlwyd y rhain yn gyntaf yn 1947 (Anhysbys, 1992). Er mwyn pennu’r meini prawf cefndir ar gyfer adnabod ffiniau safleoedd, fe gynhaliwyd adolygiad o’r llenyddiaeth gyhoeddedig ac anghyhoeddedig a geir, yn ogystal â’r canllawiau sy’n ymwneud â dewis a hysbysu SoDdGA ac ACA ystlumod. Rhoddwyd cryn bwyslais ar y mannau a ddefnyddir gan ystlumod ar gyfer chwilio am fwyd, yn ogystal â llwybrau hedfan. Mae gwaith ymchwil wedi tanlinellu pwysigrwydd canopïau a mannau lle ceir llystyfiant o amgylch clwydi magu ystlumod pedol, yn enwedig llecynnau mawr sy’n cynnwys coetiroedd. Mae rhwydweithiau da sy’n cynnwys ffiniau caeau wedi hen ddatblygu, fel gwrychoedd, llinellau coed a llecynnau o brysgwydd, yn nodweddion cynefin pwysig sy’n cysylltu’r clwydi â’r mannau bwydo. Nid ar hap a damwain y mae dwy rywogaethau y Rhinolophus yn dewis eu prae, os nad yw’r hinsawdd yn mynnu’n wahanol (Jones, 1990). Gwelir bod mannau bwydo sy’n cynnwys porfeydd wedi eu pori, sydd am y ffin â gwrychoedd aeddfed, yn bwysig i’r ddau fath o ystlum pedol. Ar y dechrau, mae ystlumod pedol mwyaf ieuainc yn hela o fewn radiws o 1 cilomedr i’r glwyd fagu (Jones et al., 1995, Ransome, 1996) wrth i’w sgiliau hedfan a chwilio am fwyd ddatblygu. Fe ddangoswyd eu bod yn ddibynnol iawn ar borfeydd a gaiff eu pori gan wartheg (Randsome, 1996). Darganfuwyd bod pryfed teiliwr yn brae pwysig i ystlumod pedol lleiaf sydd angen glaswellt byr ac amgylchiadau llaith. Mae larfa dyfrol rhai rhywogaethau’n awgrymu pwysigrwydd cyrsiau dŵr, corsydd a glannau afon yng ngoroesiad y rhywogaeth yma, ac felly yn y defnydd a wna’r ystlumod o gynefinoedd (McAney & Fairley 1988).

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EXECUTIVE SUMMARY This project is concerned with establishing guidelines for CCW staff in the identification of boundaries for bat flight lines and foraging areas of the greater and lesser horseshoe bats (Rhinolophus ferrumequinum and Rhinolophus hipposideros). This information will be used in the consideration of future notifications and extensions of Sites of Special Scientific Interest (SSSIs), and Special Areas of Conservation (SACs). Within the UK both greater and lesser horseshoe bats are protected under: The Bern Convention, the Wildlife and Countryside Act (1981) and the Conservation (Natural Habitats, &c.) Regulations 1994, which implement the Council Directive 92/43/EEC specifies a range of measures for the protection of species listed on Annex II. This includes not only the greater and lesser horseshoe bats, but also the barbastelle bat for which the first known maternity colony has recently been found in Wales (Billington 2001d). The requirements of the Regulations include the selection, designation and protection of a network of sites known as Special Areas of Conservation (SACs). The majority of these areas have already notified as Sites of Special Scientific Interest (SSSIs), these were first established in 1947 (Anon, 1992). To establish the background criteria for the identification of site boundaries, a review has been carried out of the literature currently published and unpublished and the guidelines for selection and notification of bat SSSIs and SACs. Particular emphasis has been placed on bat foraging areas and flight lines. Research has highlighted the importance of canopy and vegetation cover area around horseshoe maternity roosts particularly large areas of woodland. Good networks of well-developed field boundaries such as hedgerows, tree lines and areas of scrub are important habitat features linking the roosts to feeding areas. The choice of prey items is non random for both Rhinolophus species, unless climatic conditions dictate otherwise (Jones, 1990). Feeding areas containing grazed pasture bounded by mature hedgerows are important for both the horseshoe species. Greater horseshoe juvenile bats initially hunt within a 1km radius of the maternity roost (Jones et al., 1995, Ransome, 1996) as they develop there foraging and flight skills, they have been shown to be highly dependent on cattle-grazed pasture (Ransome, 1996). Tipulids have been found to be an important prey item for lesser horseshoe bats and require short grass and damp conditions. The aquatic larvae of some species indicate the importance of water courses, marshes and river banks in the survival of this species, and therefore in the habitat usage of the bats (McAney & Fairley 1988). On emergence bats utilise regular flight paths, which can extend over considerable distances. Movement along these flight paths show individuals flying close to the ground, and wherever possible under or close to vegetation cover. Whenever they come across the presence of gaps within vegetation both species actively reduce the flight height, particularly the lesser horseshoe bat. Horseshoe bats actively avoid foraging in, or crossing, illuminated areas and the provision of culverts can assist them in crossing roads more safely (Cresswell 2001). A series of guidelines to evaluate important features around horseshoe roosts has been included in the Appendix.

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1 INTRODUCTION The government, and hence CCW is required to notify a series of SSSIs and SACs for the protection of certain species. In Wales this includes greater and lesser horseshoe bats and also barbastelle bat, for which the first known breeding colony has recently been located (Billington 2001). Historically, the approach has been to notify maternity roosts meeting the appropriate criteria, sometimes including a small foraging area or flight lines immediately around the roost. However, the Habitats Regulations (and the Directive from which they are taken) require the protection of all the features essential for the species’ survival and thus it is important to include not only roosts but also flight lines and foraging areas. In doing so it is necessary to identify site boundaries. This report will review published and unpublished literature to provide guidelines on the identification of site boundaries for both SSSIs and SACs for greater and lesser horseshoe bats.

1.1 Evolution/ Ecology British bats belong to two families, the Vespertilionidae (of which 16 species occur within the UK), and Rhinolophidae. The two families can be readily distinguished from one another in almost all features of their anatomy, but especially by their noses. Vespertilionids have simple muzzles, whereas Rhinolophus have a complex series of skin flaps, including a horseshoe-shaped piece, around the nose (Yalden, 1993). The nose leaf is very variable in form and complexity. It is believed to serve as an acoustic lens, focusing the nasally emitted echolocation calls. The genus Rhinolophus includes about 69 species and is found through out most of the Old World, including temperate regions (Yalden, 1993, Altringham, 2001). Five species of Rhinolophus are found in Europe, and only two, greater horseshoe bat Rhinolophus ferrumequinum and lesser horseshoe bat Rhinolophus hipposideros occur within the UK. Both greater and lesser horseshoe bats are rare species that display restricted distribution patterns throughout the UK.

1.1.1 Greater horseshoe bats On mainland Europe the greater horseshoe bat is found in Belgium, Luxemburg and the south of Germany, Poland, Ukraine and Russian Federation. It is also found on many of the larger Mediterranean islands belonging to mainland European states and on Cyprus and Malta. Within the UK, the greater horseshoe bat is one of the rarest species in the UK Entwistle et al. (2001) with the distribution restricted to southwest England and South Wales. Originally a cave roosting bat, they have adapted and utilised many man made structures, with many maternity colonies in Europe now found in buildings particularly older larger houses and farm buildings. Dietary studies have found that they are selective feeders preferring larger insect prey such as moths and beetles with crane flies (Tipulidae), caddis flies (Trochoptera) and parasitic wasps (Ichneumonoid) being secondary and tertiary items of choice. Beetles constitute the greatest proportion of the bats’ dietary intake are mainly from the family of largest insects Scarabaeidae, cock chafer (Melolontha melolontha), small dung beetle (Aphodius sp.) and various types of large dung beetles (Geotrupes sp.) (Duvergé 1996, Ransome 1996, 1997 & 1997b). Radio-tracking studies for many colonies over several years show a consistent specialised hunting technique for greater horseshoe bats (Ransome 1996 Duvergé 1996) and the use of foraging areas with a similar structure. Observations have shown foraging greater horseshoes bats fly close to and within physical clutter, where they were observed hawking, perch-feeding, flying close to hedges, landing on the ground and/ or gleaning to catch prey (Jones and Rayner

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1989, Duvergé, 1996). This is supported by theoretical predictions, based on their wing morphology and echolocation techniques (Altringham 2001). Some findings of studies of lesser horseshoe bat have shown they travel quickly from the roost to a foraging area at approximately 1 - 2m above grassland, alongside linear features such as tall hedgerows and woodland edge (Bontadina, Schofield, Naef-Daenzer 2002). Research by Billington has shown this to only be the case in completely open areas, in several studies bats have been recorded and observed flying 2-5m above ground level (beside vegetation) and in some cases several metres up at canopy level (Billington 1999, 2000 & 2001c). It appears that ancient woodland (Bontadina et. al. 2002) and permanent pasture are two key habitats for this species (Ransome 1996). These habitats provide the bats with insect food and linear features such as woodland edges and hedges, which they use as flight paths. Studies in the southwest of England showed that greater horseshoe bats generally preferred ancient semi-natural woodlands and cattle grazed pastures as foraging sites and that juveniles needed foraging sites within a much smaller radius of the roost than adults (Duvergé 1996).

1.1.2 Lesser horseshoe bats In central and southern Europe lesser horseshoe bats are widespread extending as far eastwards as the Middle East but its status is rare. Distribution of the lesser horseshoe within the UK is restricted. Populations are centred in Western Ireland, Wales, and southwest England. Lesser horseshoe bats are one of the smallest bats in the UK, displaying slow highly manoeuvrable flight patterns and echolocation adapted for detecting insect wing beats in cluttered environments. These behaviours, together with, together with dietary studies, support the importance of woodland and canopies in its foraging activity. Lesser horseshoe bats feed mainly in dense broadleaved woodland and areas of wet woodland, bank side vegetation and parkland. They actively avoid open areas and instead use tree lines, woodland edges over grown hedges and vegetated banks of streams to move between roosts and woodland feeding areas (Schofield & Bontadina 1999). The high importance of semi or unimproved wet pasture bounded by hedgerows has been found in the main foraging areas of one of the largest European colonies at Glynllifon in Gwynedd (Billington 2001a & 2002a).

1.1.3 Flight morphology Bats of the Rhinolophus family are specialised having broad wings with narrow tips with low wing loading resulting in a generally slow but highly manoeuvrable flight they also have high and constant frequency echolocation calls with a high duty cycle (Altringham, 2001, Bontadina et al. 2002). They detect and take insects at close range, using constant frequency calls (CF) to detect fluttering insects. Greater horseshoe bats produce an echolocation call that is dominated by a CF component of 50ms, preceded and followed by short frequency modulated pulses (FM) (<5ms). The use of CF calls starting and terminating in FM pulses is typical of bats flying close to and within foliage.

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Comparison of feeding behaviour of the lesser and greater horseshoe bats shows although both have flexible foraging styles, the lesser horseshoe bat is predominately an aerial hawker, whereas the greater horseshoe can spend much of its time fly catching (Duvergé & Jones 1994). Perch hunting, or fly catching, is where the bat feed by hanging from a perch, intercepting passing prey. They use echolocation techniques like those feeding in vegetation but have variable aspect ratio and wing loading, since flight performance may be dictated by factors other than foraging.

1.2 Roosting Ecology Bats spend a large period of their life within the roost. Their roosting habits influence local and global distribution, densities, foraging and mating strategy, social structure and seasonal movements and even the morphology and physiology of bats. By choosing a suitable roost, bats can gain many advantages:

• Protection from the weather. • Protection from predators – ‘The selfish herd’. (Hamilton, 1971) • Cheaper thermoregulation – energetic savings during roosting. • Reduced commuting to foraging sites. • Improved mating opportunities. • Information transfer – knowledge of foraging and roosting sites • Competition avoidance – few other vertebrates can make use of most bat roosts.

Similarly foraging behaviour can also be divided into a number of different aspects:

• Selection of foraging areas • Prey selection • Competition for resources • Predator avoidance

However, the processes involved in roost selection and foraging behaviour are complex, with many mutually dependent interactions (Altringham, 2001). The availability of suitable roosts will influence foraging behaviour, but roosting behaviour itself may be influenced by the abundance and dispersal of food, which in turn are influenced by the habitat types present and habitat management. Existing maternity roosts are of the utmost importance, where the reproductively active female bats for the colony gather to rear their young, often sharing these roosts with non-breeding females and males. The bats are strongly attached to these traditional maternity sites, and the loss of them through either roost disturbance; removal of animals for research purpose; exclusion; remedial timber treatment; vandalism and habitat change (Stebbings and Griffith, 1986) could be detrimental to the population. Both Rhinolophus sp. use night roosts usually located on the boundaries of foraging sites (Duvergé 1996, Schofield 1996, Jones et al. 1995, Billington 1999, 2000, 2001a, 2001c & 2002a). These are important in a number of ways, they reduce intra-specific competition as they enable individuals to diverge and forage further afield and occasionally it may be advantageous for bats to remain in these satellite roosts during the day to conserve energy levels rather than return to the maternity roost that same night.

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When pronounced changes of weather occur reduction in temperature, heavy rainfall or gales may cause bats to remain at these roosts instead of returning to the main roost. For females, as pregnancy progresses, satellite roosts become more important and their value cannot be overestimated as they enable heavily pregnant females to forage in areas that would otherwise be denied (Schofield, 1996). The loss of satellite roosts can result in increased competition for suitable foraging sites close to the maternity roost and this may reduce the productivity of the colony. Furthermore, the regular usage of satellite roosts over a number of years could promote the establishment of new maternity roosts as more individuals use them (Schofield, 1996). If the number of adults in the maternity roost increases to the point at which the surrounding habitat is close to its capacity, then it may be more beneficial and energetically advantageous for some of the colony to remain permanently in the satellite roost (Schofield, 1996). Over a period of years the female young of the bats roosting in the satellite roost would remain and a new maternity colony would become established. So, not only is the identification and conservation of maternity roosts important, but also that of satellite roosts (Schofield, 1996, Billington 1999, 2000, 2000a, 2001c & 2002a). Since night roosts are mainly used at night, they can be any structure that provides fairly waterproof shelter, including open structures that are brightly lit in the daytime, but so long as they provide a safe sanctuary to consume and digest food at night, bats will use them. In general, lesser horseshoe bats tend to use more sheltered enclosed buildings than do greater horseshoes. Open sided farm buildings, barns, chimneys of derelict buildings, stables, garages, eaves of houses, branches of large trees, even climbing ivy can be used as night roosting places (Billington 1999, 2000, 2001a, 2001c & 2002a, Ransome and Hutson 2000, Schofield et al., unpub 2003). The more sheltered and dimly illuminated night roosts are also used during the day. Research has also highlighted the importance of canopy and vegetation cover area around the roost (Schofield, 1996, Ransome, 1996, Schofield, et al., unpub 2003.). Vegetation at winter roosts may encourage winter foraging to be more successful in mild winter spells when windy and wet conditions often occur. Emergence times have been linked to ambient light levels (Ransome, 1996, Racey et al., 1987) At higher latitudes the duration of darkness is reduced, which will limit the foraging time available, however with the presence of vegetation around the roost exit, individuals will exit at a time closer to dusk as they provide shelter and protection from flying predators (Ransome 1996, Racey et al. 1987, Schofield 1996, Jones et al. 1995). Schofield (1996) found that the clearing of a line of trees used as a commuting route from a church to woodland had a marked effect; it was shown that emergence times were delayed by 30-40 minutes. The main maternity roost, satellite roosts and suitable foraging habitat tend to be all linked by linear structures such as hedgerows, tree-lines and riparian vegetation.

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1.3 Key threats to bats The main threats to bats today consist of:

• Loss or degradation of habitat. • Habitat isolation through fragmentation, including access denied to key foraging areas

due to the construction of new road systems (Lode, 2000), or urban areas. • Decline in insect diversity and abundance. • Loss or damage to roosts. • Loss of linear linkage from roosts to foraging sites. • Changes in stock management. • Increase usages of insecticides/pesticides can build up through the food chain, one effect

is to sterilise dung through the use of worming compounds, preventing dung beetles from breeding.

1.4 Legislation Under British and European legislation it is an offence to deliberately capture or kill any bat species, to deliberately, or recklessly disturb the animal, or to damage or destroy a breeding site or resting place used by these animals. There is an equivalent legislation in Northern Ireland under The Wildlife (Northern Ireland) Order 1985. Bats are protected under:

1.4.1 The Bern Convention Bats receive protected status by their listing on Appendix II of the Council of Europe Bern Convention. This listing and the UK’s Accession to the convention resulted in the Wildlife and Countryside Act being passed into the UK law.

1.4.2 1981 Wildlife and Countryside Act Protects bats and their roosts in England, Scotland and Wales.

1.4.3 The Habitats Directive All European bat species are protected under The Council Directive 92/43/EEC of May 1992 on the conservation of natural habitats and of wild fauna and flora (the Habitats Directive). This Directive became effective in June 1994 and serves to ensure that rare species and their habitats receive strict protection and that appropriate monitoring of populations will be undertaken. There are twenty-four articles in the Council Directive. Article III, Conservation of natural habitats and habitat species, deals with Special Areas of Conservation (SACs). “Member States shall endeavour to improve the ecological coherence of Natura 2000 (sites) by maintaining and where appropriate, developing, features of the landscape which are of major importance for wild flora and fauna as referred to in Article 10. “…..to encourage the management of feature of the landscape which are of major importance for wild flora and fauna. Such features are those which by virtue of their linear and continuous

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structure (such as rivers with their banks or the traditional systems for marking field boundaries) ……are essential for the migration dispersal and genetic exchange of wild species” (Article 10). The main objectives of the habitats directive are to contribute towards ensuring biodiversity through the conservation of natural habitats and of wild fauna and flora in the European territory of the member states to which the treaty applies (Article 2.1) The Greater horseshoe bat Rhinolophus ferrumequinum is listed on Schedule 5 of the Wildlife and Countryside Act (1981), Annexes IIa and IVa of the European Habitats and Species Directive, and Appendix II of the Bern Convention. The Lesser horseshoe bat Rhinolophus hipposideros is also listed on Schedules 5 and 6 of the Wildlife and Countryside Act (1981), Annexes IIa and IVa of the European Habitats and Species Directive, and Appendix II of the Bern Convention.

1.5 Guidelines for the selection and notification of Bat SSSIs and SACs The 24 articles of the Habitats Directive “specify a range of measures, including conservation of features in the landscape that are important for wildlife, the protection of species listed in the annexes from damage, destruction or over exploitation, the surveillance of natural habitats and species, and ensuring that introductions of non-native species are not detrimental to naturally occurring habitats and species. The most stringent obligations relate to the selection, designation and protection of a network of sites – Special Areas of Conservation (SACs).” Article 4.1 of the Habitats Directive requires stages of approach, on the basis of the criteria stated in Annex III (stage 1), that each Member state shall propose a list of species indicating which species in Annex II that are native to its territory the sites host. For animal species that have large distribution ranges these sites shall correspond to the places within the natural range of such species, which present the physical or biological factors essential to the life and reproduction. The criteria to be employed in stage one can be summarised for both the habitat and species present For the habitat as:

1. Degree of representativity. 2. Area. 3. Degree of conservation of habitat structure and functions and restoration possibilities. 4. Global assessment of conservation value, (an overall assessment based on the three

above). For the species as:

1. Population size and density. 2. Degree of conservation of the features of the habitat that are

important for the species, and restoration possibilities. 3. Degree of isolation of the population in relation to the species

natural range. 4. Global assessment of conservation value.

Annex III (stage two), requires the assessment of the overall importance of the sites in the biogeographical regions and the EU as a whole.

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Criteria for stage two assessments may be summarised as:

1. Relative value of the site at national level. 2. Relationship of the site to migration routes, or its role as part of an ecosystem on both

sides of one or more community frontiers. 3. Total area of the site. 4. Number of Annex II species present. 5. Global ecological value of the site at the level of the biogeographical region, and or EU

as a whole.

Annex III of the Habitats Directive is concerned with criteria for selecting sites eligible for identification as sites of community importance and designation as special areas of conservation. In 1915 the UK produced a provisional list of 273 areas, worthy of protection as nature reserves. This work helped to prepare the ground for the first official strategy for nature conservation, set out in 1947 and led to a selection of national series of sites notified as site of Sites of Special Scientific Interest (SSSIs) (Anon, 1992).

1.6 Relationship of SACs to SSSIs It is not appropriate to assume, that all of the UK’s SSSIs should be put forward as candidate Special Areas of Conservation (cSACs). Many SSSIs have no Annex II species present or any significant numbers, and so cannot be regarded as of Community importance within the meaning of Directive. Even where sites do have habitat types and species listed in a Directive they may not qualify for selection when assessed against the criteria set out in Annex III of the Directive and other principals established (Anon, 1992). 2 AIMS This project is concerned with the greater and lesser horseshoe bat species. To review the guidelines for selection and notification of bat SSSIs and SACs and

established background criteria. To review the literature currently published and unpublished, particularly that relating to

bat foraging areas and flight lines. To develop guidelines for CCW staff for the identification of boundaries for bat flight

lines and foraging areas 3 METHODS Papers, reports and journals published and unpublished on horseshoe bats were collated from organisations, individuals, libraries and by searching the world wide web. Sources of information were obtained from: British Library Boston Spa British Library London John Rylands Library Manchester Internet English Nature Country Council for Wales

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Papers collected by the authors Vincent Wildlife Trust Leeds and Bristol Universities 4 RESULTS

4.1 Habitat fragmentation Habitat fragmentation may affect the abundance and diversity of bats, and it is possible it could affect their population numbers in the long run (de Jong 1995 Quoted in Duvergé 1996). Fragmentation of lesser horseshoe flight routes occurred when the A487 road south of Caernarfon in Gwynedd was built (Billington 2001a & 2003a) and numbers of bats crossing the A477 in Pembrokeshire have reduced following road improvements (Wyatt pers. com.). In an environment where there is an increasing loss or fragmentation of habitats due to agricultural advancements or urbanisation, it is important to find out what efforts are required for effective conservation of the bats Rhinolophus species. To a certain degree fragmentation can be beneficial to Rhinolophus sp. as this increases the ratio of edges present within the area; if hedgerows or tree lines are established and maintained between the junction of the two habitats, improving the diversity of both flora and fauna (Schofield, 1996). Rhinolophus sp. usually hunts within 5 metres of woodland edge or hedgerows (Ransome and Hutson 2000) and therefore the more linear habitat available the great the area of habitat available for potential usage by bats. However on a negative side fragmentation can also be damaging to these two species. The creation of large fields with little linear content will deny many areas within and beyond to the bats, as it has been shown that they will actively avoid crossing or foraging in open areas (Billington 1999, 2000, 2001a, 2001b, 2002a & 2003a, Ransome 1984 and Schofield, 1996), putting greater pressures on the surrounding habitat and its population numbers. Reduced dispersal, inbreeding and other problems associated with the creation of genetically isolated populations through fragmentation can effect a population (Duvergé, 1996). Greater horseshoe bats have been recorded flying up to 12km from their roosts in Somerset (Billington 2001c), and over 14km in Pembrokeshire (Duvergé 1997). Jones has found through DNA research the Pembrokeshire greater horseshoe colony appears to be genetically isolated from those in Somerset and Gloucestershire (Jones pers. com.). It is possible with the loss of linear linkage systems this genetic flow could be permanently lost. When flight paths are intersected by road systems, bats usually cross established roads at points where the gaps in canopy or vegetation are at a minimum (Matthews pers. comm.). Where traditional routes are intersected by newly created roads bats will initially continue to cross despite gaps in vegetation cover being far greater than usually tolerated, but within months the number of bats using these routes will decrease as fragmentation occurs along other flight routes (Billington 2001b & 2003a). This enables emergence as close to dusk as possible providing both protection from diurnal aerial predators and unfavourable environmental conditions such as strong winds and heavy rainfall. Horseshoe bats never fly directly into the open unless there is no alternate route for them to take. (Jones et al. 1995).

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4.2 Hedgerows Rhinolophus sp. is noted for having their summer and winter roosts relatively close, often within a few kilometres of each other (Billington 2001a & 2001b). However, whether occupancy is either within a maternity roost or a hibernaculum, bats must be able to commute to their foraging areas safely. Ransome and Hutson (2000) report they do so by using well defined sheltered flight lines. In contradiction to this, important lesser horseshoe hibernation sites have been recorded in North Wales one at 380m altitude on the side of an exposed mountain side devoid of any vegetation cover, but with dry stone walls present (Billington 2001a & 2003b). Alterations or poor management of the habitat associated with these flight lines are likely to reduce or prevent access to certain foraging areas and so restrict food supply. If large enough, gaps formed within hedgerows can actually prevent the movement of certain species (Billington 1999). Greater horseshoe bats flying across gaps in hedgerows were shown to alter the height at which they flew as light levels dropped. Schofield (1996) found that lesser horseshoe bats started crossing gaps when light levels reached 21.0 lux. The height at which they flew remained below 1m until light levels had dropped to about 4.0 lux after this point bats flew slightly higher, up to 1.5m. He found that as light levels dropped below 1 lux, bats were recorded flying up to 4m above the ground. Through radio telemetry it has been shown that bats ‘roam’ a lot between different foraging sites throughout the night, using linear structures as their key communication routes (Billington 1999, 2000, 2001a. 2001c & 2002a, Ransome and Hutson 2000). A study carried out by Schofield (1996) showed the importance of hedgerows and woodland edges as commuting routes for the lesser horseshoe bat, and recorded that bats actively avoid foraging in and crossing open areas, with individuals choosing longer routes along linear structures against crossing shorter more direct routes across open fields (Schofield, 1996, Ransome 1984). As well as roaming between foraging sites, individuals visit a number of night roosts - even at an early age greater horseshoe bats carried out two to three foraging bouts per night and visited two to three night roosts. Adults often visited 7 feeding areas and 8 satellite roosts per night (Duvergé 1996).

Not only do high hedgerows provide important corridors between sites (Schofield et al. 2003), but they also provide refuge shelters for prey items, livestock, and the bats themselves, particularly in bad weather conditions. They can assist in acting as shelters from the wind, reducing wind speeds for economical hunting flight and areas insects themselves will congregate in. They can discourage soil erosion and can protect crops from wind damage. Livestock tend to rest near or below hedgerows or woodland edges, resulting in a concentration of their dung along these sites. It is possible accumulations of dung can form in such places increasing the concentration of dung beetles, and other insects living in or attracted to dung. These are likely to be near sites favoured by hunting or perching bats, or even those that are just ‘commuting’ between sites (Ransome and Hutson 2000). Cattle can also influence the shape of the hedgerow’s growth in a beneficial way. They graze the lower hedge levels creating an umbrella shape and expose bare twigs at about 2 metres height. These twigs provide suitable perching places for the bats, and the umbrella shape provides overhead protection from aerial predators and also shelter from rainfall for both bats and the insects they prey upon. The bare twigs, (in the range of 5 -10mm diameter) used by Rhinolophus

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sp. for perching may be chosen for several reasons, for their safety from predators, as well as their size and position in relation to good-prey capture opportunities. The perch may also be used whilst a large prey item is dismembered and consumed, after a successful hunt (Ransome and Hutson 2000). Tall thick hedgerows have been found to be particularly important foraging sites for both horseshoe species harbouring insect prey species (Billington 1999, 2000, 2001a, 2001c & 2002a). Schofield (1996), highlighted the fact that bats do not use fence lines to commute along, however this has been proven not to be the case by Schofield himself in subsequent work and recorded by other fieldworkers (Kaczanow pers. com.), but it is strongly recommended that existing fence lines be replaced with hedgerows, or scrub vegetation not only for the use by bats but for other mammal species.

4.3 Topography Topography is shown to be a significant factor to consider in conservation of habitats for foraging horseshoe bats. Steep-sided valleys are shown to be superior to flat land in promoting earlier births (Ransome 1997). Ransome’s (2002) findings state that conservation efforts should be directed towards regions that are sheltered from high winds, and on south, or southwest facing slopes. Billington (1999) found the Cheddar greater horseshoe foraging grounds to mainly be on the warm south facing slopes of the Mendip Hills. A mile north of these slopes the temperature can be over 3C lower and the ground flora up to 3 weeks behind. The unique warm climate is utilised for growing soft fruit and vines.

4.4 Foraging Research has proven that after emerging from the roost, individuals linger close by before moving off to distant foraging areas (Billington 1999 & 2000, Jones et al. 1995 and Schofield 1996 & 1999) often moving out to within 2-3km radius.

4.4.1 Lesser horseshoe bats Lesser horseshoe bats have repeatedly been found ranging 1.5km and 6km from two separate roosts in Gwynedd and at times over 10km (including a juvenile). These pronounced differences between the foraging ranges will be affected by the colonies’ size, roost suitability, proximity of foraging habitat, weather and possibly other factors as well (Billington 2001a, 2002a & 2002b). Billington (2001a) recorded lesser horseshoes foraging along watercourses in coniferous plantations particularly during inclement weather. Schofield et al. (2003) recorded three of their study animals using conifer plantations for short periods of time. However, the close proximity to broadleaf woodland may generate suitable insect prey that may be migrating through the plantation (Schofield et al. 2003) and therefore the importance of coniferous plantations in lesser horseshoe foraging areas should not be over estimated. The majority of the most important foraging areas around Glynllifon have been found to be associated with wet semi-improved pasture bounded by hedgerows or scrub (Billington 2001a & 2002a).

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4.4.2 Greater horseshoe bats Adults greater horseshoe bats were identified to have a foraging range of three kilometres from radio telemetry studies at three sites in southwest England (Duvergé 1996 & Jones et al. 1995). Stebbings (1982) reported that one female flew from Carew Castle to Stackpole, Pembrokeshire in one night a distance of over 10km. Duvergé (1997) radio tracked bats in Pembrokeshire from a maternity roost, adults ranged up to 11.4km and juveniles 8km to foraging grounds. Billington (1999, 2000 & 2001c) has frequently found bats foraging 3 – 7km from the roost, individuals have been recorded foraging up to 10.2km away and bats were regularly recorded foraging up to 6km from their roost. Jones et al. (1995) recorded many individuals flying distances of 10km to hibernate. Popular foraging sites are those with overgrown mature hedgerows particularly around cattle or horse grazed pasture, scrub, woodland and wooded watercourses (Billington 1999, 2000 & 2001c and Duvergé 1996). Juvenile bats initially hunt within a 1km radius of the maternity roost (Jones et al., 1995 and Ransome 1996) and are highly dependent on cattle-grazed pasture (Ransome 1996). The foraging distance gradually increases with age (Duvergé 1996, Ransome 1996 and Jones et al. 1995). The need for juveniles to familiarise themselves with their surroundings upon leaving the maternity roost may be one possible explanation as to why juvenile bats remain within close proximity and explore the areas they can reach although they are not able to fly very far (Duvergé 1996). This limitation in flight upon first emergence may be due to a lack of ossification of the bones, and incomplete growth (Altringham, 2001, Jones et al., 1995). After 55 – 60 days juveniles are recorded foraging up to distances of 2-3km from the maternity roost, matching that of the adults within the colony (Jones et al., 1995). Billington (2001c) recorded juvenile bats (<60days old) foraging 4.5km from the roost and Duvergé (1996) had recorded them up to 3.6km from the same colony in north Somerset. By 30-40 days growth of the forearm ceases; however the fingers continue development until 60days. Hence not only maternal quality influences the development of the juvenile but also the young’s foraging capabilities influence the final growth of the skeleton and other body tissues (Jones et al. 1995 and Ransome & Hutson 2000). Considering that the initial foraging success for these bat species influences its subsequent survival potential, the provision of favourable feeding habitat close to the maternity roost should significantly increase population levels (Jones et al. 1995). Greater horseshoe bat populations are believed to be influenced by roost foraging habitat quality since the higher the levels of key prey generated the early the births will be (Ransome 1996). On average the young do not feed independently at all until they are 29 days old. At this point their diet normally consists of Aphodius rufipes, which is therefore a key prey species (Ransome 1997). There are 19 species of Aphodius occurring in the UK. Aphodius rufipes is the main one utilised by greater horseshoe bats. It is a large, profitable food item (10-13mm in length, 93mg wet mass; 30mg dry mass). It is truly nocturnal and if ambient temperatures permit flight (>9C) (Ransome 1966) it will fly through out the night. Long lived, readily available to feeding bats in large quantities from late July until October, with a peak in early August at a time when young bats start to feed, and female bats are in the their last third of lactation. Females usually feed upon moths from June to late August (Ransome 1996 & 1997). Aphodius is a dung dependent insect. It utilises fresh dung which it leaves within a day or two therefore it is essential that grazing cattle be kept close to the maternity roosts, particularly as Aphodius is such a key prey item for juveniles and lactating females. However the productivity

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of insect numbers within a season can be affected by climatic conditions (Ransome 1996 &1997). Droughts can cause cow pats to dry quicker and become unsuitable for usage more rapidly. Therefore the provision of shaded habitats acts as a refuge from the suns rays. Dung in forests is protected from heavy rains and/or high levels of sun exposure compared to dung in exposed habitats. Jones (1990) found that approximately 29% of the diet by volume consisted of beetles associated with cow pats, however horse and sheep dung is also beneficial particularly when excreted in sheltered environments, as it dries out rapidly if exposed and soon becomes unusable by the Aphodius spp. In investigations carried out by Taylor, French, and Waiwood (1978) (statement made by Ransome 1996) on the effects of moth species, their findings show that on a grading of woodland to urban habitats (range: woodland, gardens, arable land, buildings) moth numbers decline dramatically from thousands to hundreds across this series, and that the diversity index though more stable also showed declining trends. Ransome (1996) again states that Waring (1989) upon the comparison of a conifer plantation and fresh coppice, with adjacent dense deciduous coppice, found that the former two had lower moth populations than the dense deciduous coppice. However, the habitat requirements of a key prey item, and the animals own morphology support the importance of both cattle grazed pasture and mixed woodland within the initial 3km radius of the maternity roost and pasture or wooded watercourses within 5km of the roost. It is not only the habitat requirements of Aphodius sp. that indicates the importance of cattle-grazed pastures and mixed deciduous woodland but that of other insect species too. Ransome (1996) found through dietary analysis that the same three key prey items; moths (Lepidoptera) Melolontha melolontha and Aphodius Sp. (Coleoptera; Scarabidae) dominate the diets of bats. Other prey items include Geotrupes, Hymenoptera, Tipulidae, and small dipeterans. These findings are supported by other studies carried out by Ransome 1997, 2000 & 2002 and Jones 1990. Winter feeding comparison studies on lesser horseshoe bats (Ransome 2002), have shown that key prey items (Ophion wasps, Aphodius beetles and Scatophaga stercoraria dung flies) over a two year period of 1997/1998 are the same in both winters (though not their proportions). When compared to other sites, the same prey items were found to be present in faecal samples, though again not in the same proportions, which can be put down to habitat differences. In Ransome’s report (2002) eight prey items were identified through dropping analysis. They are Ophion, wasps; Aphodius; Geotrupes; Tipulidae; small dipterans, moths, dung fly and a small proportion of unidentified prey items. Other studies have shown that the choice of prey items is a non random occurrence for both greater and lesser horseshoe bats, unless climatic conditions dictate otherwise (Jones 1990 and Ransome 1997, 2000 & 2002). Geotrupes is a genus of dung beetle. They are a seasonal insect, present in spring and autumn and relatively scarce when compared to Aphodius sp. Geotrupes can be found in numbers of 1-2 adults per cow pat, whereas 1 cow pat can support up to 9 adult Aphodius species. Dietary findings indicate that Geotrupes may be a more important food source in winter (Ransome 1996 & 1997) when other prey items are not in fly; further supporting the need for cattle grazed pasture near hibernation roosts. The cockchafer (Melolontha melolontha), is a large nutritious profitable prey item. (20 – 25mm long, males mean mass 872mg wet mass, range 695 – 1055mg (n-11) females even large (Ransome 1996). The adults are active May to June, for a brief few weeks. They feed on deciduous tree leaves, and the females are dependent on pastures with short grass to oviposit in, returning to woodland to feed.

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4.5 Artificial lighting Street lamps do not benefit all bats equally. (Rydell & Racey 1995 and Blake et al., 1994). Bats whose echolocation pulses are adapted for cluttered situations such as the Rhinolophus do not seem to exploit insects around street lights, they actively avoid such areas, and the erection of artificial lighting within foraging regions or along flight lines can be damaging to the foraging activities of both horseshoe species. However, other species, such as the, Nyctalus, Vepertilio, Eptesicus and Pipistrellus, who frequently use aerial-hawking techniques to hunt, take advantage of the congregation of insects around artificial lighting, and use them to their advantage (Rydell & Racey 1995 and Blake et al. 1994).

4.6 Climate The nightly range of individual bats from roosts varies greatly according to many factors, including light levels at time of emergence, proximity of roost exit / entrance to the nearest vegetation, needs of the bat, availability of insects and the weather. Insect density usually peaks at or just before dusk, and as temperatures decrease rapidly so too do insect numbers. The sooner the bats can begin foraging the higher their success rates will be (Schofield 1996 and Ransome 1997). Studies have shown that the deterioration in the weather affects flight activity (Billington 2001a) temperatures below 80C at dusk emergence time have shown a marked reduction in flight activity, which could be a direct result of a decrease in insect diversity due to bad weather conditions. If weather is permitting the pregnant females will forage every night during pregnancy and lactation to feed their young (Altringham 2001), therefore emphasising the importance of vegetation for the encouragement of foraging in bad weather, through the protection it provides (Ransome & Hutson 2000). It is important for bats to emerge and feed as soon as dusk falls, as a peak of insect intensity occurs then.

4.7 Insecticides and Pesticides The introduction of pesticides and insecticides to agriculture, and changes in agricultural grazing regimes, can have detrimental effects on the insect populations on which the bats feed. Ivermectin is an antiparasitic drug, usage of this should be avoided in areas where greater horseshoe bats feed. Ivermectin excreted by cattle may reduce the density of Coleoptera found in cowpats (Jones 1990). Rumenal bolus designed to release ivermectin slowly over 120 days would produce unsuitable manure for the life cycle of dung beetles and other dung dwelling insects. It could potentially do enormous damage if used in livestock herds on a widespread programme (Jones 1990), particularly around horseshoe bat maternity roosts, or foraging ranges. Rotation of cattle with sheep and the usage of alternate drugs such as the milbemycin moxidection (sold as Cydectin ®, Cyanamid) the benzimidazoles fenbendazole (sold as Panacure®, Hoechst) or oxibendazole would help prevent the creation of nematode parasitic infections and control parasitic loads. Livestock rotation would also reduce the need for drug treatment (Jones 1990).

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5 DISCUSSION Observations show that horseshoe bats leaving to forage use regular flight paths, which can extend for considerable distances. They fly close to the ground, mostly close to, or beneath, vegetation cover. They avoid flying directly into open areas upon exiting roosts unless there is no alternative route, a behavioural trait that is possibly a result of predation pressures. Existing maternity roosts, where reproductively active female bats gather to rear their young, are of the utmost importance. Deterioration of colonies can occur through roost loss or disturbance; exclusion; remedial timber treatment; vandalism or habitat change (Stebbings & Griffith, 1986). Hedgerows, woodland edges around grazed pasture, wooded/tree lined watercourses, marshes, and scrub areas have proven to be the most valuable foraging environments. Bats have been shown to forage up to 10km away from the roosts. Key radial zones are: 1km Lesser and greater horseshoe bats – it is vital to retain wooded areas and vegetation cover (including scrub), and habitat links i.e. woodland, tree lines, hedgerows and possibly even limited sections of walls and fences.

All woodland and enclosed vegetation within a few hundred metres of virtually every roost is likely to be important to the bats.

1-3km Lesser and greater horseshoe bats – it is vital to maintain hedgerow systems, scrub, wetland or marsh areas, and habitat links. Areas of thick hedgerows or scrub adjacent to cattle grazed pasture are of the highest significance for greater horseshoe bats as hedgerows adjacent to semi improved damp or wet ground are for lesser horseshoe bats.

Virtually all areas containing extensive hedgerows (particularly higher overgrown ones), scrub especially surrounding pasture and or wet ground will be important to the bats.

3-7km Lesser horseshoe bats; this zone is only liable to be important for some of the larger colonies of a few hundred bats the aim is to maintain habitat links through the areas. Greater horseshoe bats; areas with thick hedgerows around grazed pasture and pronounced habitat links should be maintained, although not all areas will be used.

Some areas of extensive hedgerows (particularly higher overgrown ones), scrub and wet woodland - especially surrounding pasture and or wet ground, will be important to the bats.

7-10km Lesser and greater horseshoe bats; only a small part of this area is likely to be used for foraging but flight routes may lead further connecting to other roost sites. The aim should be to maintain habitat links through the area.

Some areas of extensive hedgerows (particularly higher overgrown ones), scrub and wet woodland - especially surrounding pasture and or wet ground, will be important to the bats. Some of the most pronounced areas of extensive hedgerows (particularly higher

overgrown ones), scrub and wet woodland - especially surrounding pasture and or wet ground will be important to the bats.

Before any major developments are allowed within 10km of any greater horseshoe roost or large lesser horseshoe roost details studies should be made to consider potential impacts. Sustaining existing hedges, and linear linkage systems within a radius of 10km from the roost will ensure

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successful access to forage sites. There will be a number of important areas within 5km of any horseshoe roost. Encouraging the expansion of linear linkage increases the edge effect. This in turn creates an high concentration of fauna at the intersection of any two habitats and helps maintain links to feeding areas or other roost sites. Tall thick hedges close to cattle grazing pastures create not only suitable foraging habitat for the bats, but also safe flight passages between foraging bouts. Both species of Rhinolophus within the UK have been shown to ‘roam’ between sites throughout the night at some times of the year. Hedgerows and woodland edges can influence the microclimate within the immediate vicinity that will affect invertebrate populations. They can act as blockades against the wind, reducing wind speeds and making flight more energetically economic. Woodland areas can protect against the cold elements, and the rain, encouraging flight activity to continue in conditions that otherwise would not be suitable for bats. In general, the future planting of native broadleaf trees instead of conifers should be encouraged, not only for the benefit of bats but also for the survival of other native species. The continuity of existing hedgerows should be maintained, as it has been found that gaps within them can have a marked effect upon the behaviour of the bats, forcing them to alter the height at which they cross over such gaps, or indeed avoid crossing them altogether. Although it is beneficial to bats if hedgerows are allowed to become overmature. The planting of more hedgerows and tree lines across large tracts of fields and pastures will not only assist preventing soil erosion due to the elements, but will also create smaller fields so that hawking bats can utilise a large proportion of the field area and provide links to further feeding areas or roost sites. The combination of creating new linear linkage system, the maintenance of existing ones, and the replacement of wire fences with hedgerows tree lines or scrub vegetation will be beneficial not only to bat species but other wild fauna too. They encourage and assist the migration of animals between sites that would otherwise be isolated populations, in turn encouraging the genetic flow of a species, reducing the risk of inbreeding and other problems associated with the creation of genetically isolated populations. Lesser and greater horseshoe bats; only a small part of this area is likely to be used for foraging but flight routes may lead further connecting to other roost sites. The aim should be to maintain habitat links through the area.

Some areas of extensive hedgerows (particularly higher overgrown ones), scrub and wet woodland - especially surrounding pasture and or wet ground, will be important to the bats. Some of the most pronounced areas of extensive hedgerows (particularly higher

overgrown ones), scrub and wet woodland - especially surrounding pasture and or wet ground will be important to the bats.

Before any major developments are allowed within 10km of any greater horseshoe roost or large lesser horseshoe roost details studies should be made to consider potential impacts. Sustaining existing hedges, and linear linkage systems within a radius of 10km from the roost will ensure successful access to forage sites. There will be a number of important areas within 5km of any horseshoe roost.

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Encouraging the expansion of linear linkage increases the edge effect. This in turn creates an high concentration of fauna at the intersection of any two habitats and helps maintain links to feeding areas or other roost sites. Tall thick hedges close to cattle grazing pastures create not only suitable foraging habitat for the bats, but also safe flight passages between foraging bouts. Both species of Rhinolophus within the UK have been shown to ‘roam’ between sites throughout the night at some times of the year. Hedgerows and woodland edges can influence the microclimate within the immediate vicinity that will affect invertebrate populations. They can act as blockades against the wind, reducing wind speeds and making flight more energetically economic. Woodland areas can protect against the cold elements, and the rain, encouraging flight activity to continue in conditions that otherwise would not be suitable for bats. In general, the future planting of native broadleaf trees instead of conifers should be encouraged, not only for the benefit of bats but also for the survival of other native species. The continuity of existing hedgerows should be maintained, as it has been found that gaps within them can have a marked effect upon the behaviour of the bats, forcing them to alter the height at which they cross over such gaps, or indeed avoid crossing them altogether. Although it is beneficial to bats if hedgerows are allowed to become overmature. The planting of more hedgerows and tree lines across large tracts of fields and pastures will not only assist preventing soil erosion due to the elements, but will also create smaller fields so that hawking bats can utilise a large proportion of the field area and provide links to further feeding areas or roost sites. The combination of creating new linear linkage system, the maintenance of existing ones, and the replacement of wire fences with hedgerows tree lines or scrub vegetation will be beneficial not only to bat species but other wild fauna too. They encourage and assist the migration of animals between sites that would otherwise be isolated populations, in turn encouraging the genetic flow of a species, reducing the risk of inbreeding and other problems associated with the creation of genetically isolated populations. 6 ACKNOWLEDGEMENTS The Countryside Council for Wales for funding this study, particularly Liz Halliwell and Jean Matthews for collating and providing information. The following people and organisations for providing information : - John Altringham Geoff Billington Bob Haycock Gareth Jones Jean Matthews Annie Poole Len Wyatt Liz Halliwell Marie Dee Rawlinson Countryside Council for Wales English Nature Publications Vincent Wildlife Trust The British Library Boston Spa The British Library London

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APPENDIX: GUIDANCE FOR THE IDENTIFICATION/ MANAGEMENT OF HORSESHOE FLIGHT LINES AND FORAGING AREAS Key radial zones are: 1km Lesser and greater horseshoe bats – vital to retain wooded areas and vegetation cover (including scrub), and habitat links i.e. woodland, tree lines, hedgerows and possibly even limited sections of walls and fences.

All woodland and enclosed vegetation with a few hundred metres of virtually every roost is likely to be important to the bats. The vegetation immediately around the roost must be maintained at all cost. All woodland, wooded watercourses, hedge lined lanes or even small roads are likely to

be key features bats use. To cross some open areas bats may use fences or walls but the use is liable to be limited –

most likely where habitat features have been removed in the past The maintenance of cattle grazed pasture around greater horseshoe roosts and damp/ wet

ground around lesser horseshoe roosts should be considered vital in this area. 1-3km Lesser and greater horseshoe bats – vital to maintain hedgerow systems, scrub, wetland or marsh areas, and habitat links. Areas of thick hedgerows or scrub adjacent to cattle grazed pasture are likely to be of highest significance for greater horseshoe bats and hedgerows adjacent to semi improved damp or wet ground for lesser horseshoe bats.

Virtually all areas containing extensive hedgerows (particularly higher overgrown ones), scrub especially surrounding grazed pasture and/ or wet ground will be important to the bats. The maintenance of these significant areas is vital to maintain the bats foraging areas. Habitat links – woodland, hedgerows, wooded watercourses must be maintained to

ensure bats can commute further out of this zone 3-7km Lesser horseshoe bats; only liable to be important for some of the larger colonies of a few hundred bats, maintain habitat links through the areas. Greater horseshoe bats; areas with thick hedgerows around grazed pasture and pronounced habitat links should be maintained, not all areas will be used.

A significant proportion of the most pronounced areas of extensive hedgerows (particularly higher overgrown ones), scrub and wet woodland - especially surrounding pasture and or wet ground will be important to the bats.

7-10km Lesser and greater horseshoe bats; only a small part of this area is likely to be used for foraging but flight routes may lead further connecting to other roost sites, maintain pronounced habitat links through the area.

Some of the most pronounced areas of extensive hedgerows (particularly higher overgrown ones), scrub and wet woodland - especially surrounding pasture and or wet ground will be important to the bats. These will be difficult to predict without carrying out radio tracking studies.

All zones Removal of habitat features or increase in night lighting may stop bats from using some routes.

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Documents

A review of horseshoe bats flight lines and feeding areas ...apps.fdean.gov.uk/_Assets/docs/Allocations examiner/Examination D… · Greater horseshoe juvenile bats initially hunt