results of a desk-study, habitat ‘truthing’ ryall’s

Report to:-

CEMEX UK Operations Ltd

Wolverhampton Road

Oldbury

Warley

West Midlands

B69 4RJ

October 2015

RESULTS OF A DESK-STUDY,

HABITAT ‘TRUTHING’ &

SURVEY FOR BATS AT

RYALL NORTH, RYALL’S

COURT FARM, RYALL COURT

LANE, UPTON-UPON-SEVERN,

WORCESTERSHIRE WR8 0PF

~~~~~~~~~~~~

CONTENTS

1. TECHNICAL SUMMARY...................................................................................... 1

2. INTRODUCTION..................................................................................................... 2

3. BAT APPRAISAL PROCESS................................................................................. 8

4. ROOST HABITAT ASSESSMENT...................................................................... 19

5. COMMUTING/MIGRATION HABITAT ASSESSMENT............................... 29

6. FORAGING HABITAT ASSESSMENT.............................................................. 38

7. THE SURVEY TEAM............................................................................................ 45

8. SURVEY METHODS: ROOST SURVEY........................................................... 48

9. ROOST SURVEY RESULTS................................................................................ 56

10. SURVEY METHODS: COMMUTING/MIGRATION & FORAGING

HABITAT SURVEY............................................................................................... 57

11. COMMUTING/MIGRATION & FORAGING HABITAT SURVEY

RESULTS................................................................................................................ 73

12. IMPACT ASSESSMENT: ROOSTING HABITAT............................................ 92

13. IMPACT ASSESSMENT: COMMUTING/MIGRATION & FORAGING

HABITAT................................................................................................................ 93

14. CONCLUSIONS..................................................................................................... 99

15. REFERENCES...................................................................................................... 100

APPENDIX A. A REVIEW OF THE COMMUTING RANGES OF BRITISH BATS USED TO

DEFINE AN APPROPRIATE RADIUS FOR SEARCHES OF HISTORIC DATA-SETS………..…. 111

APPENDIX B. RESULTS OF TREE ROOST MAPPING AT RYALL NORTH……................…..…. 115

APPENDIX C. PHOTOGRAPHS OF THE TWO TREES WITH SUITABLE POTENTIAL ROOST

FEATURES WITHIN RYALL NORTH………....................................................................................…. 120

APPENDIX D. CORRESPONDENCE WITH MS. JULIA HANMER; CHIEF EXECUTIVE OF THE

BAT CONSERVATION TRUST………......…............................................................................................ 126

__________________________________________________________________________

Report authors: Henry Andrews MSc CEcol MCIEEM & Leanne Butt BSc MSc ACIEEM.

Final proof: Leanne Butt.

This report has been prepared by AEcol (Andrews Ecology Ltd) with all reasonable skill and

diligence, within the terms agreed with the client.

No part of the report may be reproduced without prior written approval of AEcol.

No liability is accepted in respect of the use of data, conclusions or other material contained in this

report for any purposes other than those specific to this report.

© AEcol 2015

AEcol & Andrews Ecology Ltd are registered Trademarks.

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CEMEX UK OPERATIONS LTD BATS

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RESULTS OF A DESK-STUDY, HABITAT ‘TRUTHING’ & SURVEY FOR BATS

AT RYALL NORTH, RYALL’S COURT FARM, RYALL COURT LANE, UPTON-

UPON-SEVERN, WORCESTERSHIRE WR8 0PF

1. TECHNICAL SUMMARY

1.1.1 CEMEX UK Operations Ltd are seeking planning permission to extract sand and

gravel from c. 50.73 ha of land at Ryall North, Ryall’s Court Farm, Ryall Court

Lane, Upton-upon-Severn, Worcestershire WR8 0PF (hereafter referred to as ‘the

site’).

1.1.2 A Preliminary Ecological Assessment of the site performed by AEcol in April 2014

concluded that the site had the potential to be exploited by 12 species of bats. All bat

species and their roosts are legally protected under the Conservation of Habitats and

Species Regulations 2010 (& as amended) and the Wildlife & Countryside Act 1981

(& as amended). AEcol were therefore commissioned to undertake a bat survey at

Ryall North.

1.1.3 In order to satisfy ODPM Circular 06/2005, a ‘structure-based’ approach

(Lindenmayer et al. 2000) was taken to ‘scope-out’ habitats, the loss of which would

not be likely to materially affect bats. This ensured that resources were targeted

solely to habitats that have been demonstrated (within published white-papers) to be

of value to specific bat species.

1.1.4 The Ryall North bat survey comprised:-

Desk-study comprising a data-search and a structure-based habitat assessment of

roost habitat, commuting/migrating routes and foraging habitat;

Truthing of potential roost habitat (Potential Roost Feature (PRF) assessment),

commuting/migrating routes and foraging habitat; and

Survey of potential roost habitat (PRF climb and inspect surveys),

commuting/migrating routes and foraging habitat (the latter two using passive

ultrasound monitoring over 12 nights in three periods; July, August and

September 2014).

1.1.5 All aspects of the structure-based approach, truthing and subsequent survey for bat

roosts, commuting/migration routes and foraging habitat were evidence-supported

and performed to a high standard. Furthermore, the methods employed were both

proportionate to the level of risk, ensured all personnel involved adhered to the

Chartered Institute of Ecology and Environmental Management (CIEEM) Code of

Professional Conduct in all areas, and all aspects of the findings of the High Court in

the Morge judgment were satisfied.

1.1.6 An individual sporadically occupied tree-roost occupied by low numbers of either

Daubenton’s bat Myotis daubentonii or noctule Nyctalus noctula was recorded. A

detailed mitigation and compensation strategy has been provided to the Mineral

Planning Authority. Derogation under licence will be required, but there are no

grounds to suggest Natural England would refuse this licence.


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1.1.7 Commuting routes exploited by seven bat species were recorded. None of the

species recorded are absolutely reliant upon linear landscape elements, and none of

the linear landscape elements present are the sole communication between any

known or unknown bat-roost and core foraging areas. There are no grounds to

suggest the development would result in a barrier effect on any local population of

any bat species sufficient to require derogation under licence. A detailed restoration

strategy has been provided to the Mineral Planning Authority. This will reinstate the

network of commuting routes for all species recorded.

1.1.8 Seven bat species were recorded during the foraging habitat survey. There are no

grounds to suggest the site represents more than 5% of the foraging habitat resource

available to bats occupying known roosts outside the site. There are no grounds to

suggest any of the habitats within the site are part of a core foraging area of any

local colony of any bat species occupying any unknown roost, during the most

sensitive July lactation period. The loss of foraging habitats will be phased, and

therefore temporary. Abundant foraging habitat will exist in the locality for all the

species identified during the survey. There are therefore no grounds to suggest the

development would result in a disturbance affect sufficient to warrant derogation

under licence due to the loss of foraging habitat in respect of any bat species.

Nevertheless, the detailed restoration strategy submitted to the Mineral Planning

Authority for approval will result in a 57% increase in hedgerow length, and a 33.24

ha (10,980%) increase of suitable foraging habitat for all species recorded during the

survey.

2. INTRODUCTION

2.1 Development proposal

2.1.1 CEMEX UK Operations Ltd are seeking planning permission to extract sand and

gravel from c. 50.73 ha of land at Ryall North, Ryall’s Court Farm, Ryall Court

Lane, Upton-upon-Severn, Worcestershire WR8 0PF (hereafter referred to as ‘the

site’).

2.2 Site context

2.2.1 The site is centered upon Ordnance Survey (O.S.) grid reference SO852419 and is

located c. 0.8 km from Upton-upon-Severn, Worcestershire, on the east side of the

River Severn. The site is located in a wider area of residential housing, pastoral and

arable fields. The location and extent of the site is provided at Figure 1 on the

following page.

2.3 Habitats present

2.3.1 Habitats within the site in 2014 were broadly divided into 12 Phase 1 (JNCC 2010)

habitat types comprising:-

A2.1 – Woodland and scrub / Scrub / Dense/continuous (c. 0.2 ha);


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A3.1 – Woodland and scrub / Parkland/scattered trees / Broadleaved (c. 0.6 ha);

B2.2 – Grassland and marsh / Neutral grassland / Semi-improved (c. 5.45 ha);

B4 – Grassland and marsh / Improved grassland (c. 10.65 ha);

G1.1 – Open water / Standing water / Eutrophic (c. 0.07 ha);

G2 – Open water / Running water (c. 820 m);

J1.1 – Miscellaneous / Cultivated/disturbed land / Arable (c. 30.81 ha);

J2.1.1 – Miscellaneous / Boundaries / Intact hedge / Native species-rich (c. 2220

m);

J2.4 – Miscellaneous / Boundaries / Fence (c. 2360 m);

J2.6 – Miscellaneous / Boundaries / Dry ditch (c. 770 m);

J2.8 – Miscellaneous / Boundaries / Earth bank (c. 220 m); and

J4 – Miscellaneous / Bare ground (c. 0.8 ha).

© Crown copyright 2015. All rights reserved. Ordnance Survey licence number 100050075.

Figure 1. The location and extent of the site within the wider landscape.

2.3.2 A Phase 1 (JNCC 2010) plan showing the location and extent of broad habitat types

within the site is provided at Figure 2 on the following page.

2.4 Background

2.4.1 A Preliminary Ecological Assessment of the site performed by AEcol in April 2014

concluded that the site had the potential to be exploited by 12 species of bats

comprising:-

Serotine Eptesicus serotinus;

Bechstein’s bat Myotis bechsteinii;


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Brandt’s bat Myotis brandtii;

Daubenton’s bat Myotis daubentonii;

Whiskered bat Myotis mystacinus;

Natterer’s bat Myotis nattereri;

Leisler’s bat Nyctalus leisleri;

Noctule Nyctalus noctula;

Nathusius’ pipistrelle Pipistrellus nathusii;

Common pipistrelle Pipistrellus pipistrellus;

Soprano pipistrelle Pipistrellus pygmaeus; and

Brown long-eared bat Plecotus auritus.

Figure 2. The location and extent of Phase 1 (JNCC 2010) habitats within the

site.


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Legal status

2.4.2 All bat species and their roosts are legally protected under the Wildlife &

Countryside Act 1981 (& as amended) and the Conservation of Habitats and Species

Regulations 2010 (& as amended), which implements the provisions of EC

Directive 92/43 (‘Habitats Directive’), the latter of which has been subject to legal

interpretation within case law comprising (amongst others) Morge (FC) (Appellant)

v Hampshire County Council (Respondent): Hilary Term [2011] UKSC 2 On appeal

from: 2010 EWCA Civ 608. More generally, under the Natural Environment and

Rural Communities (NERC) Act 2006, a Planning Authority has a duty to conserve

biodiversity.

Planning Policy

2.4.3 Planning policy is set out in the National Planning Policy Framework and with

further guidance provided in ODPM Circular 06/2005, which defines the duty of

Planning Authorities when considering applications for developments that may

affect legally protected species. Additional consideration is required in respect of

UK Biodiversity Action Plan (BAP) and Local (LBAP) Priority Species.

2.5 Wildlife & Countryside Act 1981 (& as amended)

2.5.1 All bat species are listed on Schedule 5 of the Wildlife & Countryside Act 1981 (&

as amended) and receive legal protection under Part 1, Section 9, sub-section (4)(b

& c) which states:

Subject to the provisions of this Part, a person is guilty of an offence if intentionally

or recklessly—

(b) he disturbs any such animal while it is occupying a structure or place

which it uses for shelter or protection; or

(c) he obstructs access to any structure or place which any such animal

uses for shelter or protection.

2.6 Conservation of Habitats and Species Regulations 2010 (& as amended)

2.6.1 Part 3, regulation 41, paragraph (1) of the Conservation of Habitats and Species

Regulations 2010 (& as amended) states that:

A person who—

(a) deliberately captures, injures or kills any wild animal of a European

protected species;

(b) deliberately disturbs wild animals of any such species;

(c) deliberately takes or destroys the eggs of such an animal; or

(d) damages or destroys a breeding site or resting place of such an animal;

is guilty of an offence.


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2.6.2 Part 3, regulation 41, paragraph (2) states that disturbance of animals includes in

particular any disturbance which is likely:

(a) to impair their ability—

(i) to survive, to breed or reproduce, or to rear or nurture their young;

or

(ii) in the case of animals of a hibernating or migratory species, to

hibernate or migrate; or

(b) to affect significantly the local distribution or abundance of the species to

which they belong.

2.6.3 The offence in paragraph 2.6.1 applies regardless of the stage of the life of the bat.

2.6.4 Under the terms of the Habitats Directive, developments that would result in a

breach of the protection afforded to European Protected Species (EPS) may

nevertheless be allowed by derogation under Article 16 which is transposed by

Regulation 44 of the Conservation of Habitats and Species Regulations 2010 (& as

amended). By derogation, licences may be issued for certain prescribed purposes

listed in Regulation 44(2)(a)-(g) where the licensing authority is satisfied that two

tests are met, which are set out in Regulation 44(3):-

1. A licence must not be issued unless there is no satisfactory alternative; and

2. It must not be issued unless the action authorised by the licence would not be

detrimental to maintaining the population of the species concerned at a

favourable conservation status in its natural range.

2.7 Natural Environment and Rural Communities (NERC) Act 2006

2.7.1 Under the Natural Environment and Rural Communities (NERC) Act 2006, a

Planning Authority has a duty to conserve biodiversity. This duty is set out at

Section 40, which states:

“(1) Every public authority must, in exercising its functions, have regard, so far

as is consistent with the proper exercise of those functions, to the purpose of

conserving biodiversity.

(2) In complying with subsection (1), a Minister of the Crown, government

department or the National Assembly for Wales must in particular have

regard to the United Nations Environmental Programme Convention on

Biological Diversity of 1992.

(3) Conserving biodiversity includes, in relation to a living organism or type of

habitat, restoring or enhancing a population or habitat…”

2.8 National Planning Policy Framework (NPPF)

2.8.1 In the most basic terms, Paragraph 109 of the NPPF states that:


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“The planning system should contribute to and enhance the natural and local

environment by... minimising impacts on biodiversity and providing net gains in

biodiversity where possible...”

2.8.2 In addition, Paragraph 117 identifies the need for planning policies to identify and

map components of local ecological networks (both designated sites and stepping

stones in-between), and promote the preservation, restoration and enhancement of

UK Biodiversity Action Plan (BAP) Priority Habitats and ecological networks,

whilst also promoting the protection and recovery of Priority Species.

2.9 ODPM Circular 06/2005

2.9.1 ODPM Circular 06/2005 states that:

“The presence of a protected species is a material consideration when a planning

authority is considering a development proposal that, if carried out, would be likely

to result in harm to the species or its habitat.”

2.9.2 Therefore:

“It is essential that the presence or otherwise of protected species, and the extent

that they may be affected by the proposed development, is established before the

planning permission is granted, otherwise all relevant material considerations may

not have been addressed in making the decision.”

2.9.3 However:

“Bearing in mind the delay and cost that may be involved, developers should not be

required to undertake surveys for protected species unless there is reasonable

likelihood of the species being present and affected by the development.”

2.10 Biodiversity Action Plans (BAP)

2.10.1 The UK Biodiversity Action Plans were written in order to provide detailed

strategies for the conservation of the most threatened habitats and species at a

national level. Such habitats and species are known as ‘Priority Habitats’ and

‘Priority Species’. Lists of Priority Habitats and Species are updated regularly to

ensure they remain relevant to the true conservation situation.

2.10.2 Under Section 40 of the NERC Act 2006, Planning Authorities must “have regard”

for the conservation of biodiversity in England, when carrying out their normal

functions. In particular Local Planning Authorities will use it to identify the species

and habitats that require specific consideration in dealing with planning and

development control.

2.10.3 There are currently seven species of bat listed as UK BAP Priority Species

comprising barbastelle Barbastella barbastellus, Bechstein’s bat, noctule, soprano


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pipistrelle, brown long-eared bat, greater horseshoe bat Rhinolophus ferrumequinum

and lesser horseshoe bat Rhinolophus hipposideros.

2.10.4 In addition, some counties have BAP with locally specific objectives. The

Worcestershire BAP is reviewed within the data-search review at Sub-section 3.9.

3. BAT APPRAISAL PROCESS

3.1 General

3.1.1 The bat appraisal process typically comprises three stages:-

1. Desk-study;

2. Truthing; and

3. Survey.

3.2 Desk-study

3.2.1 The first stage in any ecological assessment in support of planning is the

performance of a thorough desk-study. The desk-study should establish whether

sufficient information already exists to provide a robust account of the likely bat

interest within the site prior to development, and confidently assess the probable

effects of the development proposal, both in terms of what the development will

comprise and how this will directly affect bats in terms of loss of the habitats that

are currently present, as well as indirectly, in terms of obstruction or displacement.

This is achieved by collating what is conclusively known and can reasonably be

predicted (by extrapolating what is known), but also what is unknown and cannot be

reasonably predicted. Data typically included within the desk-study comprise a data-

search of historic bat records within the site and stratified radii, results of botanical

and habitat surveys (i.e. Preliminary Ecological Assessment), and scientific accounts

of individual bat species.

3.2.2 If the desk-study concludes that sufficient information is available to confidently

establish that the development would be unlikely to result in harm to bats, and

satisfies legislative mechanisms and policy obligations, then no further action will

be required and the bat appraisal may conclude at this stage. If however the desk-

study concludes that insufficient information exists, it should establish exactly what

is needed and direct action accordingly.

The ‘structure-based’ approach

3.2.3 All stages of the Ryall North desk-study use a ‘structure-based’ approach using

habitat characteristics as an indicator of population parameters. This is not a new

concept, but although the principles pre-date 2000 they were only defined and

termed the ‘structure-based’ approach1 by Lindenmayer et al. (2000).

1 Structure-based indicators are stand-level and landscape level (spatial) features that can be predicted to be of

value to the target species. These include individual habitat and its structural complexity, plant species

composition, connectivity and heterogeneity etc. (Lindenmayer et al. 2000).


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3.2.4 Numerous studies have demonstrated that some habitats have wide ranging appeal to

a high number of bat species, some have specific appeal to individual species, and

some are avoided. Identifying habitats known to be closely associated with the

presence, distribution and abundance of specific bat species, and (if present)

evaluating their quality, is often used to direct bat appraisal effort and resources

(Hayes et al. 2009).

3.2.5 In addition, the structure-based approach means only the species likely to be present

and affected by changes are considered, but at the outset all those species are

identified and given equal weight. This is necessary because surveys simply

represent a snapshot of activity, and are not ‘closed’, as occupancy may change

between individual survey visits (Scott & Altringham 2014). The artificial

boundaries of a site do not represent the boundaries of a bat colony’s seasonal

territory or annual range. This can result in the failure to detect a colony even when

it is roosting within range of the site, but due to temporary emigration from the

locality, it remains within its home range but outside the bounds of the survey and

therefore not available for detection (Scott & Altringham 2014). The structure-based

approach is therefore used to identify the potential for all species to occur within a

site, thereby ensuring the potential importance of habitats within the site is

considered for all species known to occur within a locality, regardless of whether a

survey is performed or not and, if a survey is performed, regardless of whether the

species is recorded or not.

3.2.6 The structure-based approach is the most responsible balance between the need to

satisfy policy and legislative commitment, and the financial commitment a physical

survey represents to a developer. This approach is fundamental to the satisfaction of

ODPM Circular 06/2005.

3.3 Truthing

3.3.1 Although a broad habitat type may appeal to several species, additional factors may

make it more or less suitable. For example, the greater horseshoe bat favours pasture

surrounded by hedges, habitats which may be identified within a Preliminary

Ecological Assessment, therefore suggesting the species might exploit the site.

However, greater horseshoe bats favour cattle-grazed pasture surrounded by tall,

bushy and continuous hedges. Therefore, if the site actually contained horse-grazed

pasture surrounded by low and discontinuous hedges, there would be less grounds to

suggest the site is likely to be important for foraging greater horseshoe bats, and that

its loss would be likely to result in harm to the species.

3.3.2 Truthing is therefore a valuable tool, and typically comprises a daytime inspection

performed by a licenced bat ecologist to assess the qualitative characteristic of the

habitats present. While the example above relates to foraging habitat, truthing may

also be used to assess roost and commuting/migration habitat quality.


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3.4 Bat survey

3.4.1 Where the desk-study and truthing offer insufficient information, or where

derogation under licence is likely to be required in order for the development to

proceed legally, then a survey might have merit, particularly if the survey can be

predicted to provide information missing from scientific accounts, or fill-in missing

site-specific information (i.e. the conclusive identification of the bat species present,

the approximate numbers of bats that will be affected, the purpose a specific roost

serves etc.). However, this will depend on the specific circumstances; the desk-study

and truthing should define the question the survey is to answer, and to how

confident the surveyor is whether or not the methods and equipment currently

available will provide data that can be analysed to give a meaningful answer to that

question.

3.4.2 If however, the equipment, survey and analysis methods currently available can be

predicted to produce an inconclusive and subjective discussion, resulting in a

hypothesis that will be unlikely to significantly alter the conclusions already reached

at the desk-study stage, then careful consideration should be given to whether such a

survey would be worthwhile.

3.5 Due diligence framework for desk-study and truthing in respect of bat roost

habitat

3.5.1 The following sub-section sets out a due diligence ‘risk assessment’ process for the

desk-study and any subsequent truthing in respect of roosting habitat.

3.5.2 Part 3, regulation 41, paragraph (1) item (d) of the Conservation of Habitats and

Species Regulations 2010 (& as amended) states “A person who damages or

destroys a breeding site or resting place of [a bat or bats] is guilty of an offence. It

should be noted that this is an ‘absolute’ offence that does not require any fault

elements to be proved in order to establish guilt.

Risk Assessment

3.5.3 Referring back to ODPM Circular 06/2005, the first stage of the appraisal in respect

of roosting bats will logically comprise a risk assessment identifying whether or not

any potential roost habitat (i.e. buildings, caves, trees etc.) exists within the

development footprint and whether this is already known to be occupied (i.e.

whether the Local Records Centre (LRC) holds historic data on roosting bats within

that habitat).

3.5.4 If no potential roost habitat exists, the appraisal may be concluded at this stage and

no further action taken. If however roost habitat does exist, then its suitability can be

assessed by truthing which typically comprises a daytime inspection.

3.5.5 If the ground truthing concludes that the habitat is unsuitable, then the appraisal may

be concluded at this stage. If however the habitat is found to be suitable its presence

is identified and an evidence-supported appraisal performed to define which bat


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species might exploit it, when, and for what purpose (i.e. nursery, mating and/or

hibernation).

3.6 Due diligence framework for desk-study and truthing in respect of

commuting/migrating and foraging habitat

3.6.1 The following sub-section sets out a due diligence ‘risk assessment’ process for the

desk-study and any subsequent truthing in respect of commuting/migrating and

foraging habitat.

3.6.2 The legal protection given to bats under the Conservation of Habitats and Species

Regulations 2010 (& as amended) can be broadly broken down into that which

protects the bats themselves and that which protects their habitat. At first sight this

may appear straightforward; the bats themselves are protected against killing,

injuring and disturbance, and their roosts are protected against damage or

destruction. However, although commuting routes and foraging habitat are not

specifically protected, the judgement of the Supreme Court in the case of Morge

(FC) (Appellant) v Hampshire County Council (Respondent): Hilary Term [2011]

UKSC 2 On appeal from: 2010 EWCA Civ 608 was that the legislation afforded to

bats with regard to disturbance does give some degree of protection to wider habitat

in some (but not all) situations.

3.6.3 Deferring to the Guidance document on the strict protection of animal species of

community interest under the Habitats Directive 92/43/EEC (EUROPEAN

COMMISSION 2007), Morge v Hampshire County Council acknowledged that

“Disturbance is detrimental for a protected species e.g. by reducing survival

chances, breeding success or reproductive ability.” This is defined as “any

disturbing activity that affects the survival chances, the breeding success or the

reproductive ability of a protected species or leads to a reduction in the occupied

area.”

3.6.4 In defining disturbance, the Supreme Court therefore accepted that it encompassed

not just situations where the bats were directly disturbed by an intrusive change in

their immediate environment (such as a bright light being shone on them or loud

noise etc.), but also included changes in the wider environment that disturbed their

habitual routine. Such changes might, in some situations, include the severance of a

linear landscape element used for commuting/migrating to and from a roost resulting

in a fragmentation effect, and/or the loss of foraging habitat that formed part of the

territory of a colony thereby rendering the territory unviable and causing

abandonment (i.e. displacement).

3.6.5 Taking the disturbance legislation in isolation, Part 3, regulation 41, paragraph (1),

bullet (b) of the Conservation of Habitats and Species Regulations 2010 (& as

amended) states:

A person who deliberately disturbs wild animals of any such species is guilty of an

offence.


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(i) to survive, to breed or reproduce, or to rear or nurture their young,

or




which they belong.

3.6.7 The Supreme Court established definitions for: deliberate; and disturbance.

Deliberate

3.6.8 The definition of ‘deliberate’ is set out in paragraph 33 of Guidance document on

the strict protection of animal species of community interest under the Habitats

Directive 92/43/EEC (EUROPEAN COMMISSION 2007) which states:

“Deliberate actions are to be understood as actions by a person who knows, in light

of the relevant legislation that applies to the species involved, and the general

information delivered to the public, that his action will most likely lead to an offence

against the species, but intends this offence or, if not, consciously accepts the

foreseeable results of his action.”

Disturbance

3.6.9 Deferring again to the EUROPEAN COMMISSION (2007), it was concluded that

the disturbance offence is not limited to significant disturbances of significant

groups of animals, but covers all disturbance of EPS. However, although the

disturbance does not have to be significant, it must be certain (i.e. specific),

identifiable and real, and not fanciful.

3.6.10 In addition, the Supreme Court highlighted that a disturbing activity that affects bats

“…during the period of breeding, rearing, hibernation and migration is more likely

to have a sufficient negative impact on the species to constitute prohibited

“disturbance’ than activity at other times.” Furthermore, it must have a detrimental

impact so as to affect the favourable conservation status of the species at population

level. The Supreme Court cited Article 1 of The Habitats Directive in defining

favourable conservation status as a situation where “…the natural range of the

species is neither being reduced nor is likely to be reduced for the foreseeable

future, and there is, and will probably continue to be, a sufficiently large habitat to

maintain its populations on a long-term basis.”

3.6.11 Therefore, some degree of disturbance in terms of commuting route severance and

foraging habitat loss might be acceptable before it constituted an offence. The

Supreme Court set out that the proper approach should be to give consideration to

the effect on the conservation status of the species at population level and bio-

geographic level. It is stated that “the impact must be certain or real, it must be


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negative or adverse to the bats and it will be likely to be detrimental when it

negatively or adversely affects the conservation status of the species.”

Risk Assessment

3.6.12 Referring back to ODPM Circular 06/2005, the first stage of the appraisal in respect

of commuting/migrating and/or foraging bats will logically comprise a risk

assessment identifying:-

1. Whether data held by the LRC or the results of a site-specific survey have

established bat roosts exist within the site, or outside the site but within the

species typical nightly foraging range;

2. Whether or not any linear landscape elements that might be exploited by

commuting bats of species known to occur in the County exist within the site,

and will be severed as a result of the development, and this would represent

significant fragmentation within the wider network (i.e. the development might

represent an impassable obstruction). Particular attention should be given to

species known to occupy roosts within or outside the site; and

3. Which habitats within the site that will be lost as a result of the development, are

likely to be exploited by each bat species known to occur in the County, and to

what extent that habitat is represented in the wider locale (i.e. will there

“…continue to be a sufficiently large habitat to maintain its populations on a

long-term basis”). Again, particular attention should be given to species known

to occupy roosts within or outside the site.

3.6.13 Account should be taken of the guidance set out by the Supreme Court2:-

1. A species-by-species approach should be taken as different species will react

differently to potentially disturbing activities (for example, not all species are

reliant upon linear landscape elements for commuting);

2. Consideration should be given to any reduction in the area occupied by each bat

species (i.e. how much habitat will be lost to each species, and what proportion

of their overall foraging resource does it represent);

3. Greater emphasis should be given to actions that might affect breeding, rearing,

hibernation and migration3;

4. Consideration should be given to the rarity and conservation status of the species

and the impact of the disturbance on the local population of the species, with

rare species given greater consideration than more common species (even where

the latter may be more numerically abundant in that particular site); and

5. Greater emphasis should be attached to species that are declining in numbers

than species that are increasing.

3.6.14 If the development will not result in the severance of linear landscape elements that

might be exploited by commuting bats, then no further assessment of this aspect will

be necessary. If the opposite is true, truthing should be performed in order to inform

a reasoned and evidence-supported appraisal assessing to what extent this may be

2 Morge (FC) (Appellant) v Hampshire County Council (Respondent): Hilary Term [2011] UKSC 2 On appeal

from: 2010 EWCA Civ 608. 3 As set out under Article 12(1)(b) of the Habitats Directive which prohibits “deliberate disturbance of [EPS],

particularly during the period of breeding, rearing, hibernation and migration.”


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disturbing to local4 populations. If this assessment concludes the results will be

within acceptable limits, or that a more serious affect can be ameliorated by

alteration to the scheme design without compromising the integrity of the

development, the motive for performing a survey should be questioned. If however,

the conclusion is that there is a certain (i.e. specific), identifiable and real risk that

the development will result in a severance effect that might reasonably be predicted

to be detrimental to maintaining a population of any bat species at favourable

conservation status within its natural range, and this cannot be ameliorated to an

acceptable level within the confines of the development, a test of this hypothesis in

the form of a field-survey might provide greater confidence in the magnitude of the

effect. In this circumstance, the desk-study should identify exactly what information

is needed in order to support derogation under licence (i.e. the survey objective; the

question the survey is to answer) and whether there is sufficient confidence that the

methods and equipment available are likely to achieve the survey objective. If the

survey can be designed to achieve the objective, the desk-study should set out the

most effective method, and appropriate interval and intensity specific to the situation

(i.e. exactly which species are at risk and when in order that the way the survey will

achieve the objective is robustly demonstrated). Constraints to the methods

advocated should be clearly identified and all attempts to ameliorate them

considered and, where reasonable, acted upon.

3.6.15 In respect of loss of foraging habitat, all semi-natural habitats (and many artificial

habitats) have some value to foraging bats. The National Bat Survey found that

overall bats were widespread in Britain and recorded in 94% of the squares sampled

(Walsh & Harris 1996a). However, it should not immediately be assumed that a

survey will therefore be required in support of a planning application, or indeed

would have any merit if it was performed. To illustrate, The National Bat Survey

also established that improved grassland, arable land and moorland were strongly

avoided (Walsh & Harris 1996b). It can therefore be predicted that loss of these

habitat types would be unlikely to affect local bat populations in the absence of any

other disturbing affect. Reference to ODPM Circular 06/2005 confirms that in such

a situation, survey would not be justified. Therefore, the same risk assessment

process as set out at paragraph 3.6.14 should be followed and, where appropriate,

attempts made to anticipate predictable outcomes of habitat loss and ameliorate them

to acceptable limits within the scheme design.

3.6.16 If a survey is ultimately recommended, it should be designed to assess the effect

only upon the particular species for which there are grounds to suggest an

4 Locality will logically vary with species in line with their average commuting range. It is reasonable to

suggest that locality will encompass the territory typically visited, and in general terms, the average nightly

commuting range of the bats in a radius around a roost occupied in that particular season and for that particular

purpose. Therefore, the locality of a maternity colony of bats might be predicted to be larger than that of an

individual male, as the prey resource needed to sustain a group of bats will be larger than that of an individual

and there will be some degree of competition even within the same colony. At the most basic level, AEcol

define ‘local populations’ as those occupying known roosts within average commuting distance of the site for

that particular species. It is accepted that LRC may not hold a comprehensive record of all roosts that exist

within each species-specific Zone of Influence, however, this imperfect situation is in our opinion the only

rational way of assessing the situation (i.e. to produce a certain (i.e. specific), identifiable and real assessment,

some concrete facts (known knowns) have to be established). Where a species is present, but no roost is

identified, the impact assessment has therefore by necessity to include some hypothesis and subjective

judgment (i.e. known unknowns).


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unacceptable degree of risk and the particular habitat it exploits. Furthermore, the

survey should aim to establish whether the risk that the development will result in a

loss of foraging habitat that can be predicted to affect the survival chances, breeding

success or the reproductive ability of any bat colony, or lead to a reduction in the

occupied area (i.e. a colony might abandon a roost), and is certain (i.e. specific),

identifiable and real. The survey should therefore focus on the habitats known to be

favoured by the species potentially present, and likely to be of permanent and

consistent value, and therefore likely to be relied upon by colonies in the locality.

Particular attention should be given to the presence of colonies known to occupy

roosts within foraging range of the site. If such a survey objective cannot reasonably

be achieved, the motive for performing further survey should be questioned.

Summarising ODPM Circular 06/2005, EUROPEAN COMMISSION (2007) and

the Habitats Directive, it is essential that the extent to which protected species may

be affected is established. However, surveys should only be required where a

development would be likely to result in certain (i.e. specific), identifiable, real, and

not fanciful harm to the species. Therefore, providing there “…will probably

continue to be, a sufficiently large habitat to maintain its populations on a long-

term basis” the motive for performing a survey should be questioned.

Note: In the experience of AEcol, structural-approach assessments are, more often

than not, accurate. Careful thought should therefore be given in advance as to how

the development might be so designed to ensure that it is not detrimental to

maintaining bat populations at favourable conservation within their natural range.

The point being that money spent on a survey might yield a dividend in establishing

(within reasonable limits) that a particularly rare species is not in fact likely to be

affected, but equally the expense of the survey might be saved by not damaging the

habitat in the first place, or better spent in advance habitat creation, thereby

potentially avoiding the need for a survey at all.

3.7 Objectives of the Ryall North desk-study

3.7.1 The objective of the Ryall North desk-study comprised a risk assessment of whether

the development had the potential to:-

1. Damage or destroy a bat roost;

2. Be sufficiently disturbing to bats that it could reasonably be predicted that this

would be sufficient to impair their ability to:- a. Survive (by destruction of foraging habitat);

b. Mate (by destruction of roost and/or commuting/migrating habitat);

c. Rear young (by destruction of roost, commuting/migrating and/or

foraging habitat);

d. Hibernate (by destruction of roost habitat);

e. Migrate (by severance of linear landscape elements used for commuting

to and from a roost); or

3. Significantly affect the local distribution or abundance of any species (by

destruction of roost habitat, commuting/migrating habitat and/or foraging

habitat).


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3.7.2 The desk-study comprised:-

1. A data-search, comprising the identification of all known bat-roosts within a

pre-defined radius of the site;

2. A structure-based5 (Lindenmayer et al. 2000) habitat assessment comprising:-

a. Roost habitat, comprising the identification of all known and potential

bat-roost habitat within the site and its margins, an assessment of its

suitability and, if judged to be suitable, the definition of a hypothesis of

which species might occupy it, when and for what purpose;

b. Commuting route networks comprising the identification and mapping

of commuting habitat and, if commuting habitat is present and judged to

be suitable, an assessment of its quality and the definition of a hypothesis

of which species might exploit it and when; and

c. Foraging habitat comprising the identification and mapping of foraging

habitat, an assessment of its quality and the definition of a hypothesis of

which species might exploit it and when.

3. Identification of the conservation status of each species; and

4. Interpretation of the results, comprising a review of the data-search results,

habitat assessment results, and the conservation status of each species. Where

appropriate this information was combined with the results of the truthing to

demonstrate the need or lack of need for a field survey. Where survey is

advocated, the most appropriate method and equipment are identified, with

supporting evidence of their efficacy. Finally, predictable survey constraints are

identified and a description of how any such constraints might be ameliorated is

set out.

3.8 Data-search

3.8.1 Historic records of bat-roosts within a 5 km radius of the site were obtained from

Worcestershire Biological Records Centre (WBRC). The search radius requested for

bat-roosts are based on a review of typical nightly foraging ranges; a copy of the

review is provided at Appendix A. The results of the data-search were filtered to

remove incomplete species records and records outside an individual species typical

nightly commuting range comprising:-

Bechstein’s bat, Alcathoe’s bat Myotis alcathoe, Natterer’s bat and brown long-

eared bat – within a 1 km radius;

Soprano pipistrelle and lesser horseshoe bat – within a 2 km radius;

Whiskered bat, Brandt’s bat, common pipistrelle and grey long-eared bat

Plecotus austriacus – within a 3 km radius;

Greater horseshoe bat – within a 4 km radius; and

Barbastelle, serotine, Daubenton’s bat, Leisler’s bat, noctule and Nathusius’

pipistrelle – within a 5 km radius.

3.8.2 The data-search returned no records from the site itself but 174 records within a 5

km radius. Of these, 169 records were discarded due to incomplete information (lack

5 Structure-based assessments are accepted as a valuable tool, and may even be used for monitoring bat habitat

(Kunz & Parsons 2009).


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of species, status or inadequate location data) or were outside an individual species

typical nightly commuting range. Table 1 summarises the remaining five records.

Table 1. Bat records within species-specific radii, provided by WBRC.

SPECIES LOCATION DATE DISTANCE FROM SITE

Noctule

Nyctalus noctula SO887452

25/07/2013 4.43 km north-west

24/06/2013

Common pipistrelle

Pipistrellus pipistrellus

SO83998 44478 20/07/2010 2.21 km north-west

SO882429 26/06/2009

2.9 km west 02/06/2009

SO865404 08/06/1997 1.42 km south-east

Brown long-eared bat

Plecotus auritus SO854406 12/02/2007 0.69 km south

3.8.3 The location of roost records in relation to the site is provided at Figure 3. The

individual merits of the remaining species records are then discussed within the

relevant contextual sub-sections.


Figure 3. The location of known off-site bat roosts (provided by WBRC) in

relation to the site, stratified to include only those roosts within the typical

nightly foraging range of the species.


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3.9 Conservation status

3.9.1 The UK and Local conservation status of the 14 bat species known to occur in

Worcestershire is detailed in Table 2.

Table 2. The conservation status of bats in Worcestershire.

SPECIES UK BAP UK STATUS

(BCT 2014)

WORCESTER

BAP

WORCESTER

STATUS

Barbastelle

Barbastella barbastellus Y Rare Y Rare

Serotine

Eptesicus serotinus N Uncommon Y Rare

Bechstein’s bat

Myotis bechsteinii Y Very rare Y Very rare

Brandt’s bat

Myotis brandtii N Uncommon Y Very rare

Daubenton’s bat

Myotis daubentonii N Common Y Widespread

Whiskered bat

Myotis mystacinus N Uncommon Y

Widespread but

uncommon

Natterer’s bat

Myotis nattereri N Common Y Uncommon

Leisler’s bat

Nyctalus leisleri N Uncommon Y Uncommon

Noctule

Nyctalus noctula Y Uncommon Y Widespread

Nathusius’ pipistrelle

Pipistrellus nathusii N Uncommon Y Rare

Common pipistrelle

Pipistrellus pipistrellus N Common Y

Widespread and

common

Soprano pipistrelle

Pipistrellus pygmaeus Y Common Y

Widespread and

common


Plecotus auritus Y Common Y

Widespread and

common

Lesser horseshoe bat

Rhinolophus hipposideros Y Rare Y Uncommon

3.9.2 All conservation statuses were summarised and simplified for Ecological Impact

Assessments (EcIA) by Wray et al. (2010), who classified the species into three

conservation categories comprising ‘Common’ (population over 100,000), ‘Rarer’

(population 10,000-100,000) and ‘Rarest’ (population under 10,000). The species

assigned to each classification in England, Wales, Scotland and Northern Ireland is

shown in Table 3 on the following page.

Worcestershire Biodiversity Action Plan

3.9.3 All 14 bat species which have been recorded in Worcestershire are labelled as Local

BAP species within the records provided by WBRC. All the species are included in

one Species Action Plan (SAP; Worcestershire Biodiversity Partnership 2008),

which identifies generic risks to bat populations nationally and indeed globally. The

SAP identifies data-deficiency at county level and therefore refrains from attempting

to define specific habitat or species objectives, and instead (very sensibly)


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recommends a structured system of training to encourage further investigation in

order that conservation effort is directed where it is most likely to result in a positive

outcome.

Table 3. Wray et al. (2010) distribution and rarity categories.

RARITY ENGLAND WALES SCOTLAND NORTHERN

IRELAND

RAREST

Barbastelle*

Bechstein’s bat*

Alcathoe’s bat Greater mouse-eared bat

Grey long-eared bat

Greater horseshoe bat*

Serotine

Barbastelle*

Bechstein’s bat* Brandt’s bat

Whiskered bat

Alcathoe’s bat Noctule


Greater horseshoe bat*

Brandt’s bat

Whiskered bat

Alcathoe’s bat Leisler’s bat

Noctule


Whiskered bat

RARER

Serotine Brandt’s bat

Daubenton’s bat

Whiskered bat Natterer’s bat

Leisler’s bat

Noctule Nathusius’ pipistrelle

Lesser horseshoe bat*

Daubenton’s bat

Natterer’s bat

Brown long-eared bat Lesser horseshoe bat*

Daubenton’s bat Natterer’s bat


Daubenton’s bat

Natterer’s bat Leisler’s bat



COMMON Common pipistrelle Soprano pipistrelle


Common pipistrelle

Soprano pipistrelle

Common pipistrelle

Soprano pipistrelle

Common pipistrelle

Soprano pipistrelle

*Annex II Species colonies may be cited as a designated feature of a Special Area of Conservation (SAC) and receive additional protection, even in a situation where they are reliant upon habitat outside the SAC. Therefore, in a situation where a

colony of an Annex II species roosted within an SAC, but was nonetheless dependent upon habitat outside, all the habitat

inside and outside the SAC might be needed in order for all the attributes of the SAC to be maintained at Favourable Conservation Status (FCS).

4. ROOST HABITAT ASSESSMENT

4.1 General approach

4.1.1 A thorough bat-roost assessment of a site using a structure-based approach will

logically follow a three-stage progression comprising:-

1. Desk-study:-

a. Establish whether superficially suitable potential roost habitat exists

within the site;

b. If so, establish whether a roost is already known to occur within the site;

and

c. If the answer to both questions is no then the assessment may cease at

this stage. If suitable habitat is present, regardless of whether or not a

roost is already known to occur, the assessment should progress to Stage

2.

2. Truthing: Even where potential roost habitat is present (i.e. mature trees,

buildings, cliffs etc.) it does not necessarily mean it is in fact suitable (trees may

hold no Potential bat-Roost Features (PRF) and buildings may be entirely

sealed). Furthermore, the historic presence of a roost does not mean it is still

present; trees fall and derelict buildings deteriorate so far as to be unsuitable. It

is therefore necessary to ‘truth’ the potential of the roost habitat and the ongoing

existence of historic roosts. Truthing should:-


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a. Establish whether the roost habitat holds PRF that are available to

roosting bats;

b. Establish whether any known roosts identified by the data-search still

exist;

c. Establish whether the development will result in the damage or

destruction of these PRF (including isolation effects); and

d. If the habitat is not suitable and no known roosts exist, or the habitat is

suitable but the PRF are not under any certain (i.e. specific), identifiable

and real threat, then the assessment may cease at this stage. Where

potential for damage or destruction of a roost exists the truthing should

be sufficiently thorough to produce a hypothesis of which bat species

might be present, when and for what purpose. If the result of this exercise

is that insufficient information exists to be able to conclude that the

development will not result in damage to, or the destruction of a roost, it

may be necessary to proceed to Stage 3.

3. Survey:- a. Design and perform a survey that will assess which PRF are occupied by

bats, of which species, when, for what purpose (this may require the

identification of the sex and breeding condition of the bats present) and

in what numbers, in order that the roost can be assigned a geographical

value (i.e. Local, County, Regional, National or International)6.

4.2 Roost habitat desk-study

Habitat assessment

4.2.1 Different species of bats favour different types of roost habitat. Within these broad

distinctions there are also seasonal variations and differences between the sexes. In

defining the typical spring, summer, autumn and winter roost preferences of the bat

species potentially present, reference was made to accounts in Harris & Yalden

(2008), Dietz et al. (2011) and other sources individually cited. The roost

preferences for the 14 bat species known to occur in Worcestershire are set out in

Table 4 (spring, summer and autumn) and Table 5 (winter) on the following page.

Table 4. The typical spring, summer and autumn roost preferences exhibited

by the 14 bat species present in Worcestershire, as described in Harris &

Yalden (2008), Dietz et al. (2011) and other sources as cited.

SPECIES HABITAT NICHE EQUIVALENT PHASE 1

HABITATS

HABITAT

PRESENT IN

SITE

Barbastelle

Barbastella barbastellus Trees

A1.1.1 Broadleaved semi-natural

woodland

A3 Parkland/scattered trees (including isolated trees)

J2.3 Hedge and trees

Habitat Present:

Yes

Serotine

Eptesicus serotinus

Cliffs (Sam Dyer 2013 pers. comm.

1st June) and buildings with soffit-boxes and cavity-walls

I1.1 Inland cliff

I2.1 Quarry (hard-stone) J3.6 Buildings

Habitat Present:

No

6 See Wray et al. (2010).


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HABITATS

HABITAT

PRESENT IN

SITE

Bechstein’s bat

Myotis bechsteinii Trees

A1 Woodland A3 Parkland/scattered trees


Habitat Present:

Yes

Brandt’s bat

Myotis brandtii Trees, buildings and bridges



J3.6 Buildings J5 Other habitat (bridge)

Habitat Present: Yes

Daubenton’s bat

Myotis daubentonii Trees, caves, buildings and bridges

A1 Woodland

A3 Parkland/scattered trees

I1.5 Cave J2.3 Hedge and trees

J3.6 Buildings

J5 Other habitat (bridge)


Whiskered bat

Myotis mystacinus Buildings J3.6 Buildings

Habitat Present:

No

Natterer's bat

Myotis nattereri Trees, cliffs and buildings

A1 Woodland

A3 Parkland/scattered trees I1.1 Inland cliff

I2.1 Quarry (hard-stone)

J2.3 Hedge and trees J3.6 Buildings

Habitat Present:

Yes

Leisler’s bat

Nyctalus leisleri Trees and buildings

A1 Woodland

A3 Parkland/scattered trees J2.3 Hedge and trees

J3.6 Buildings


Noctule

Nyctalus noctula Trees


(including isolated trees)


Habitat Present:

Yes


Pipistrellus nathusii Trees and buildings



J3.6 Buildings

Habitat Present:

Yes

Common pipistrelle

Pipistrellus pipistrellus Churches and houses J3.6 Buildings

Habitat Present: No

Soprano pipistrelle

Pipistrellus pygmaeus

Churches and houses (including

modern) J3.6 Buildings

Habitat Present:

No


Plecotus auritus Trees and buildings

A1 Woodland


J3.6 Buildings



Rhinolophus

hipposideros

Natural cave systems, mines, large

old buildings and cellars

I1.5 Cave I2.3 Mine

J3.6 Buildings

J3.6 Buildings (cellar)

Habitat Present:

No

Table 5. The typical winter roost preferences exhibited by the 14 bat species

present in Worcestershire, as described in Harris & Yalden (2008), Dietz et al.

(2011) and other sources as cited.


HABITATS

HABITAT

PRESENT IN

SITE

Barbastelle

Barbastella barbastellus

Trees in woodland and cliffs (latter ref. Stebbings 1988)


woodland I1.1 Inland cliff


Habitat Present: No

Serotine

Eptesicus serotinus

Cliffs (Stebbings 1988), caves,

buildings and cellars

I1.1 Inland cliff I1.5 Cave


J3.6 Buildings (and cellars)

Habitat Present:

No

Bechstein’s bat

Myotis bechsteinii Caves I1.5 Cave

Habitat Present:

No


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HABITATS

HABITAT

PRESENT IN

SITE

Brandt’s bat

Myotis brandtii Caves, mines and cellars

I1.5 Cave I2.3 Mine


Habitat Present:

No

Daubenton’s bat

Myotis daubentonii

Cliffs (Altringham 2003), scree (BCT 2010), caves, mines, cellars

and bridges

I1.1 Inland cliff

I1.2 Scree I1.5 Cave


I2.2 Quarry spoil I2.3 Mine


J5 Other habitat (bridge)

Habitat Present:

No

Whiskered bat

Myotis mystacinus Caves, mines and cellars

I1.5 Cave

I2.3 Mine


Habitat Present: No

Natterer's bat

Myotis nattereri Scree, caves and quarry spoil

I1.2 Scree I1.5 Cave

I2.2 Quarry spoil

Habitat Present:

No

Leisler’s bat

Nyctalus leisleri Trees

A1 Woodland



Habitat Present:

Yes

Noctule

Nyctalus noctula

Trees and cliffs (latter ref. Stebbings 1988)


I1.1 Inland cliff

I2.1 Quarry (hard-stone) J2.3 Hedge and trees



Pipistrellus nathusii No data No data

Habitat Present:

No data

Common pipistrelle


Trees, cliffs (Schober &

Grimmberger 1997), caves, stone walls (Stebbings et al. 2007) and

buildings


I1.1 Inland cliff

I1.5 Cave I2.1 Quarry (hard-stone)


J2.5 Wall (rough stone only) J3.6 Buildings


Soprano pipistrelle


Trees, cliffs (Schober &

Grimmberger 1997), caves, stone

walls (Stebbings et al. 2007) and

buildings

A1 Woodland


I1.1 Inland cliff

I1.5 Cave


J2.3 Hedge and trees J2.5 Wall (rough stone only)

J3.6 Buildings

Habitat Present:

Yes


Plecotus auritus

Trees, cliffs (Gerrell 1981,

Stebbings 1988), caves, mines and

buildings


I1.1 Inland cliff

I1.5 Cave I2.1 Quarry (hard-stone)

I2.3 Mine

J2.3 Hedge and trees J3.6 Buildings



Rhinolophus

hipposideros

Natural cave systems, mines and

cellars

I1.5 Cave

I2.3 Mine J3.6 Buildings (cellar)

Habitat Present:

No

4.2.2 Reference to Tables 4 and 5 demonstrates that roost habitat exists within the site

comprising:-

A3.1 – Woodland and scrub / Parkland/scattered trees / Broadleaved, which are

considered potentially suitable for 11 bat species comprising:-

o Barbastelle for maternity, mating and transitory usage;

o Bechstein’s bat for maternity, mating and transitory usage;

o Brandt’s bat for maternity, mating and transitory usage;

o Daubenton’s bat for maternity, mating and transitory usage;

o Natterer’s bat for maternity, mating and transitory usage;


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o Leisler’s bat for hibernation, maternity, mating and transitory usage;

o Noctule for hibernation, maternity, mating and transitory usage;

o Nathusius’ pipistrelle for maternity, mating and transitory usage;

o Common pipistrelle for hibernation usage;

o Soprano pipistrelle for hibernation usage; and

o Brown long-eared bat for hibernation, maternity, mating and transitory

usage.

4.2.3 In addition, the Phase 1 survey report (AEcol 2014; dated October 2014) identified

19 Phase 1 Target Note bat features in trees which are summarised at Table 6.

Target Notes are numbered according to the Phase 1 survey report dated October

2014.

Table 6. Phase 1 Target Notes in relation to bats at Ryall North.

TARGET

No. LOCATION INTEREST

TN1.5 SO85206 42051

(Tree tag 0517)

Pedunculate oak Quercus robur pollard c. 102.4 cm dbh and c.

8.5 m tall with hollow stem, holding north-facing opening on

stem and weld between two western branches; Potential bat-

Roost Features (PRF).

TN2.1 SO85267 42383

Pedunculate oak pollard c. 108.9 cm dbh and c. 13 m tall, hollow

in base, holding large knot on east and small hole on snag of

north side of bole; PRF.

TN2.2 SO85309 42368 Pedunculate oak pollard c. 158.1 cm dbh and c. 10 m tall with

hollow bole and crown, and holding desiccation fissures; PRF.

TN2.3 SO85316 42372

Standard pedunculate oak c. 108.4 cm dbh and c. 11 m tall with

hollow stem, holding west-facing knot-hole in top most crown (c.

8 m high) and east-facing woodpecker hole (c. 8 m high); PRF.

TN2.5 SO85332 42381 Standard pedunculate oak c. 113.3 cm dbh and c. 10.5 m tall with

hollow stem, holding desiccation fissures; PRF.

TN2.7 SO85352 42269 Pedunculate oak pollard c. 100.1 cm dbh and c. 9.5 m tall with

hollow bole; PRF.

TN2.9 SO85489 42275 Standard ash Fraxinus excelsior c. 54.4 cm dbh and c. 11 m tall

holding light ivy Hedera helix cover; PRF.

TN2.10 SO85490 42267 Standard ash c. 77.5 cm dbh and c. 9.5 m tall holding light ivy

Hedera helix cover; PRF.

TN2.11 SO85497 42210

Standard ash c. 65.1 cm dbh and c. 10 m tall in hedgerow,

holding west-facing knot hole on western limb fork at c. 6 m

high; PRF.

TN3.1 SO85218 42293

Standard pedunculate oak Quercus robur c. 128.2 cm dbh and c.

17.5 m tall in hedgerow, holding lifting bark, desiccation fissures

and occlusion wood in crown on west; PRF.

TN5.1 SO85034 41779

(Tree tag 0533)

Standard pedunculate oak c. 102.8 cm dbh and c. 10.5 m tall,

holding desiccation fissures to canopy; PRF.

TN5.2 SO84930 41806 Standard pedunculate oak c. >100 cm dbh (not recorded due to

bosses) and c. 11 m tall with hollowing up northern side; PRF.

TN5.9 SO85255 41848 Pedunculate oak pollard c. 89.3 cm dbh and c. 12.5 m tall with

hollow bole; PRF.

TN6.1 SO84943 41609 Standard pedunculate oak c. 83.4 cm dbh and c. 16.5 m tall,

holding snag on limb (c. 6 m high); PRF.

TN6.3 SO85026 41548 Pedunculate oak pollard c. 201 cm dbh and c. 12.5 m tall with

hollow stem, holding lifting bark and desiccation fissures; PRF.

TN7.1 SO84911 41538 Standard pedunculate oak c. 96.8 cm dbh and c. 11 m tall,

holding lifting bark and snags; PRF.


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TARGET

No. LOCATION INTEREST

TN10.2 SO85155 41440

(Tree tag 0552)

Standard pedunculate oak c. 115.8 cm dbh and c. 22.5 m tall,

holding split low limb on south and east-facing tear-out (c. 10 m

high; PRF.


holding basal wound with large entrance; PRF.


holding knot-hole on west of stem; PRF.

Data-search

4.2.4 The data-search performed by WBRC returned no records of roosting bats from

within the site.

Roost desk-study conclusion

4.2.5 Potential bat-roost habitat exists within the site. Although no historic roost records

exist from within the site, truthing of the desk-study results was nonetheless

warranted comprising ground-mapping of trees and any PRF they might hold.

4.2.6 Figure 4 on the following page shows the location of results of the ground-mapping

of potential roost habitat comprising 19 Phase 1 Target Note bat features in trees (as

labelled in Table 6).

4.3 PRF truthing

General approach

4.3.1 PRF truthing is performed in order to establish whether superficially suitable roost

habitat is genuinely suitable, for which species and for what purpose. Conclusions

should be based both on published accounts and also on surveyor experience and

judgment.

4.3.2 Useful practical accounts of features occupied by bats in trees may be found in:-

Altringham J 2003. British Bats. Harper Collins, London.

Andrews H et al. 2013. Bat Tree Habitat Key. AEcol, Bridgwater.

PRF truthing results

4.3.3 PRF truthing comprised ground-mapping of trees for PRF followed by cataloguing,

both performed to the method set out within Andrews et al. (2013). The truthing was

performed by Henry Andrews MSc CEcol MCIEEM (Natural England bat licence

CLS00414) and Louis Pearson BSc MSc GradCIEEM on 23rd

& 24th

April 2014 and

7th

, 8th

& 10th

July 2014.

4.3.4 Ground-mapping was performed on 23rd

& 24th

April 2014 using binoculars and a

Garmin eTREX Vista H handheld GPS to pinpoint potential roost sites (Stebbings et

al. 2005). In total, 19 trees holding PRF were identified. The location of the 19


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potential bat roost trees is shown in Figure 4.

Figure 4. The location of trees holding Potential bat Roost Features within the

site.

4.3.5 Cataloguing was performed on 7th

, 8th

& 10th

July 2014 using arboreal climbing

equipment and/or ladders as appropriate to access the PRF identified, in order to

narrow-down the possibility of the feature being occupied by bats. Each PRF was

inspected using a Ridgid micro CA300 1-4 m fibre-optic endoscope with 17 mm, 9

mm and 6 mm diameter lenses as appropriate, to see whether it is suitable (Mitchell-

Jones 2004, Stebbings et al. 2005, BCT 2007a) and, if so, if bats are present or there

is evidence to suggest historic presence. All the PRF identified could be

comprehensively searched with either a 17 mm or 9 mm diameter endoscope lens

and their characteristics were recorded using a clinometer, compass, 2 million

candle-power torch and tape-measures (standard and diameter).

4.3.6 Upon cataloguing and close inspection, none of the 19 trees held bats on the dates of

survey, but four trees were considered suitable to be used by roosting bats, including

one; Tree TN10.2, which held evidence to suggest the presence of bats. The four

trees comprise:-

1. Tree TN2.3 – pedunculate oak Quercus robur with woodpecker hole on the east

and knot-hole on the west of the hollow stem (suitable, but no evidence of bat-

roost presence);

2. Tree TN2.7 – pedunculate oak with a hollow bole on the eastern side of the stem


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(suitable, but no evidence of bat-roost presence);

3. Tree TN10.2 – pedunculate oak with a tear-out on a limb on the east (suitable,

internal substrate smooth and polished, distinctive ‘grass snake-like’ smell

indicative of Daubenton’s bat or noctule); and

4. Tree TN10.4 – pedunculate oak with a basal wound on the western side of the

stem (suitable, but no evidence of bat-roost presence).

4.3.7 The results of the PRF truthing of the total 19 trees are summarised at Appendix B.

Figure 5 shows the location of the four potential roost trees.

Figure 5. The location of potential tree-roosts at Ryall North.

4.3.8 The cataloguing results were analysed using a dichotomous key provided by

Andrews et al. (2013), and by also applying surveyor experience. The results are

summarised below in the following text and in Table 7.

Table 7. Results of application of Bat Tree Habitat Key (Andrews et al. 2013) to

the four trees judged to hold suitable PRF within Ryall North.

TREE No. LOCATION BAT SPECIES

TN2.3 SO85316 42372

Daubenton’s bat T

Natterer’s bat Pm/T

Noctule Pm/Sm//T/H

Brown long-eared bat Pm/T/H

TN2.7 SO85352 42269 Not suitable as PRF below 4.6 m and 9.5 m in height


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TREE No. LOCATION BAT SPECIES

TN10.2 SO85155 41440

(Tree tag 0552)

Leisler’s bat T/H

Common pipistrelle T

Soprano pipistrelle T

TN10.4 SO85252 41463 Not suitable as PRF below 4.6 m and 9.5 m in height

Note: T – Transition roost occupied by low numbers of bats (mixed sex) or individual males; Pm –

Primary maternity, where roost feature preferentially selected by maternity colonies; Sm – Secondary

maternity, where roost feature occasionally occupied by maternity colonies; and H – Hibernation

roost.

Tree TN2.3

4.3.9 The results of the application of Bat Tree Habitat Key (Andrews et al. 2013) suggest

that Tree TN2.3 (holding a woodpecker hole and knot-hole) is potentially suitable

for:-

Daubenton’s bat as a transit roost;

Natterer’s bat as a primary maternity and transit roost;

Noctule as a primary maternity, secondary maternity and hibernation roost; and

Brown long-eared bat as a primary maternity and hibernation roost.

4.3.10 No bats or any evidence to suggest their historic presence were however recorded

during the PRF truthing. Figure C1 and Photos C1-C3 at Appendix C shows the

location of PRF on Tree TN2.3.

Tree TN2.7

4.3.11 The results of the application of Bat Tree Habitat Key (Andrews et al. 2013)

highlighted that, to date, no species of bat has been recorded occupying such a low-

level PRF in such an exposed location. No bats or any evidence to suggest their

historic presence were recorded during the PRF truthing.

Tree TN10.2

4.3.12 The results of the application of Bat Tree Habitat Key (Andrews et al. 2013) suggest

that Tree TN10.2 (holding a tear-out) is potentially suitable for:-

Leisler’s bat as a hibernation and transit roost;

Common pipistrelle as a transit roost; and

Soprano pipistrelle as a transit roost.

4.3.13 Whilst no bats were recorded, evidence in the form of smoothing and polishing of

the internal substrate, and a conspicuous ‘grass snake-like’ odour was apparent to

the PRF, which is indicative of Daubenton’s bat and noctule (AEcol own data). Bat

Tree Habitat Key author, Henry Andrews, accepts that the key is not infallible (and

frequently records that confound it), concluding that Tree TN10.2 holds a

sporadically occupied roost occupied by either up to three Daubenton’s bats, or a

single noctule. It should however be noted that the two species do occupy the same

roosts, even on the same day (AEcol own data). Figure C2 and Photos C4-C5 at

Appendix C shows the location of PRF on Tree TN10.2.


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Tree TN10.4

4.3.14 The results of the application of Bat Tree Habitat Key (Andrews et al. 2013)

highlighted that, to date, no species of bat has been recorded occupying such a low-

level PRF in such an exposed location. No bats or any evidence to suggest their

historic presence were recorded during the PRF truthing.

PRF truthing conclusion

4.3.15 The results of the analysis suggests two of the PRF identified from the ground were

of a character and internal dimensions to hold roosting bats, with seven species

identified as having been recorded in such PRF and in the environmental conditions

the trees and site encompasses. A further two PRF were identified as superficially

suitable in themselves, but the analysis was found to be data-deficient, with no roost

recorded in such features in the environmental conditions the trees and site

encompass.

4.3.16 Despite data-deficiency in two PRF, repeat survey of all the four trees identified as

holding potential roosts was considered to be proportionate to the level of risk and

was therefore advocated.

4.4 Roost survey

General approach

4.4.1 The survey method chosen should be appropriate to achieve the objective of

establishing whether the PRF is a roost and if so, to provide sufficient information to

support derogation under licence by demonstrating how the “…action authorised by

the licence would not be detrimental to maintaining the population of the species

concerned at a favourable conservation status in its natural range.”

4.4.2 Exactly how this will be established will vary according to the site-specific situation.

However, the information required will typically comprise:-

1. The bat species present;

2. The approximate average number of bats present;

3. When the bats are present;

4. The sex of the bats present and their breeding condition (whilst the number of

bats may hint at their sex in some cases, this is not true of all species, for

example, male Daubenton’s bats may congregate in relatively high numbers and

appear to the unwary to be a maternity colony); and

5. The reason they are present (i.e. transient, mating, maternity and/or hibernation).

4.4.3 Particular consideration is given to:-

1. How the species will be conclusively identified – DNA, ultrasound, visual

inspection from a distance, endoscope or hand/net/trap capture;

2. How an average count will be achieved – evening emergence survey, visual

inspection from a distance, endoscope or net/trap capture;

3. How the period in which the bats are present will be established – balancing


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proportionate survey intensity to the level of risk;

4. How the bats will be sexed and breeding condition established – hand/net/trap

capture or (if a sufficiently detailed account exists) inference from roost

structure, period of occupancy and numbers present; and

5. How the reason they are present will be established – an individual bat might be

a male, but it also might be a female about to give birth before returning to a

maternity group.

4.4.4 Survey methods and the equipment involved are described at Section 8. The

questions that each method can and cannot answer are set out, and generic

constraints inherent to them are described. In addition, site-specific constraints are

identified, and how they were ameliorated is described.

5. COMMUTING/MIGRATION HABITAT ASSESSMENT


5.1.1 The path to a physical survey of commuting/migration habitat should logically

follow the following three-stage progression:-

1. Desk-study:- a. Assess whether there is a superficially suitable network of linear

landscape elements that might be exploited as commuting/migration

routes by bat species known to occur in the County, and whether these

will be severed, and to what extent by the development;

b. Identify to what extent bat species known to occur in the County are

reliant upon linear landscape elements as commuting/migration routes,

and in particular those known to roost within identified on-site/off-site

colonies and those potentially present in on-site PRF;

c. Assess whether any severance would be likely to result in certain (i.e.

specific), identifiable and real harm to any individual species of bat due

to an impassable obstruction; and

d. If certain (i.e. specific), identifiable and real harm to the ability of a local

population of any bat species to survive, mate, rear young, hibernate

and/or migrate, or to significantly affect the local distribution or

abundance of any species cannot be confidently demonstrated, then the

assessment may cease at this stage. If superficially suitable habitat is

present and an identifiable and real risk of harm is identified, the

assessment should progress to Stage 2.

2. Truthing:- a. Establish whether the habitat that will be lost is genuinely of a suitable

quality to be exploited by commuting bats and, if so, by which species;

and

b. If the habitat is found upon close inspection to be unsuitable then the

assessment may cease at this stage. If the habitat is suitable the

assessment should progresses to Stage 3.

3. Survey:- a. Design and perform a survey that will confidently assess whether the

species known to occupy roosts in the locality exploit the linear


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landscape elements present in the site and what geographical level of

value (i.e. Local, County, Regional, National, and International) the

linear landscape elements represent7; and

b. If no such survey is possible, or proportionate to the level of risk, identify

this and conclude on the basis of the data available.

5.2 Commuting/migration habitat desk-study

Habitat assessment

5.2.1 Telemetry studies have demonstrated that most bats, upon emerging from the roost,

(predictably) fly rapidly and more or less directly to favoured foraging sites

(Altringham 2003). In commuting to these foraging grounds, many species follow

linear landscape elements such as hedgerows, woodland edges, lanes, waterways and

even small ditches and dykes (Altringham 2003). The use of these features has been

suggested as both an aid to navigation and also an anti-predator strategy (Altringham

2003).

5.2.2 Of those species that typically exploit linear landscape elements, differences in

altitude, speed and flight-path may be observed. For example, the Pipistrellus

species and whiskered bat typically fly slightly above and to one side of a hedge at

c. 4-5 m in a straight line on one side or the other, with a lazy flight that may be

paused in order for the bat to return to forage on a particular stretch if there is an

abundance of prey (H. Andrews pers. obs.). In contrast, both the brown long-eared

bat and lesser horseshoe bat fly at c. 1 m above the ground, tight to the hedge-base at

top speed, slaloming from one side to another through gateways and gaps (H.

Andrews pers. obs).

5.2.3 In addition to differences in altitude and modes of flight between species, light-

levels may also bring about temporal differences. For example, AEcol have

observed pipistrelles showing a marked preference for following linear features in

the early evening when light levels are high, but abandoning them altogether

following full dark. Furthermore, even woodland species such as the Natterer’s bat

may follow a more direct route across open fields when returning to a roost at dawn

(H. Andrews pers. obs).

5.2.4 The site holds four linear landscape elements comprising combinations of

waterways and ditches, hedgerows, fences, and tracks and roads that might be

exploited by commuting bats, but will be lost for the greater proportion of their

length as the result of the development.

Commuting ecology

5.2.5 Table 8 on the following page sets out the preferences for linear landscape elements

typically exhibited by Worcestershire’s 14 bat species, but also identifies those

species that have been shown to be migratory over large distances. It cannot be

overemphasised that there is a difference between reliance upon linear landscape



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elements, and a preference for commuting along them and this may vary with age

and breeding condition. Several bat species that typically follow such linear habitat,

may dispense with it entirely during autumn migrations between summer habitat and

winter hibernation quarters; others will use such habitat where it exists, but must

encounter wide gaps in the form of rivers, lakes, motorways, human settlements and

industrial installations on their seasonal migrations between summer roosts and

subterranean winter quarters.

Table 8. The preference for commuting along linear landscape elements

exhibited by the 14 bat species present in Worcestershire, as described in

Harris & Yalden (2008), Dietz et al. (2011), Hutterer et al. (2005) and other

authors individual cited.

SPECIES

RELIANCE ON LINEAR FEATURES

As described in Harris & Yalden (2008), Dietz et

al. (2010), Hutterer et al. (2005) and other authors

individual cited

CONCLUSION

Barbastelle

Barbastella

barbastellus

Prefers connecting features, but will cross extensive

open areas. 5 out of 6 radio-tracked bats crossed > 30

m wide motorway passing through woodland (Kerth

& Melber 2009). Continental migrations range from

10 to 290 km.

Preference but

not reliance

Serotine

Eptesicus serotinus

Usually forages and commutes over linear structures:

hedges, waterways and roads but will cross large

open areas (Verboom & Huitema 1997). Although

they orientate themselves on linear landscape

elements they fly high above them (Simon et al.

2004).

Preference but

not reliance

Bechstein’s bat

Myotis bechsteinii

Commutes along tree lines and hedgerows;

occasionally crosses open fields. Only crossed a 30 m

wide motorway passing through woodland using

underpasses (Kerth & Melber 2009). Non-migratory.

Reliance

Brandt’s bat

Myotis brandtii

Commutes along windbreaks, hedges and stream

courses avoiding open habitats. Continental

migrations range from 10 to 618 km.

Preference but

not reliance

Daubenton’s bat

Myotis daubentonii

Usually commutes along ditches, hedges, woodland

edges and trails. Maximum migration 19 km in UK.

Preference but

not reliance

Whiskered bat

Myotis mystacinus

Orientates on linear landscape elements (Simon et al.

2004) and also hunts along vegetation edges, but

does occupy open landscapes. Continental migrations

of 10-70 km not uncommon.

Preference but

not reliance

Natterer’s bat

Myotis nattereri

Orientates by linear landscape elements both on route

between roosts and foraging habitat, and also

between individual discrete areas of foraging habitat

(Simon et al. 2004). Uses connecting elements e.g.

hedges, wood banks and meadows with trees.

Considered a facultative migrant on the Continent.

Preference but

not reliance

Leisler’s bat

Nyctalus leisleri

Does follow linear landscape elements such as

hedges, forest trails or fire breaks but will cross

extensive open areas.

Neither

preference nor

reliance

Noctule

Nyctalus noctula

Almost all landscape types used and forages in open

areas.

Neither

preference nor

reliance


Pipistrellus nathusii

Often forages along linear structures, e.g. firebreaks,

forest edges but is migratory and therefore crosses

wide distances of open habitat (i.e. the North Sea).

Neither

preference nor

reliance


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SPECIES

RELIANCE ON LINEAR FEATURES

As described in Harris & Yalden (2008), Dietz et

al. (2010), Hutterer et al. (2005) and other authors

individual cited

CONCLUSION

Common pipistrelle


Forages along tree-lines and hedges but will cross

large open areas (Verboom & Huitema 1997). Takes

the shortest route over open country to foraging sites

and travels up to c. 375 m over open land (Simon et

al. 2004). Regular movements of 34 km recorded

Preference but

not reliance

Soprano pipistrelle


Typically associated with vegetation but forages

widely over lakes and rivers so can be predicted to

cross open areas.

Preference but

not reliance


Plecotus auritus

Commutes along flyways, e.g. hedgerows, treelines,

banks, fences, rides but has been known to cross dual

carriageways of c. 30 m width (Berthinussen &

Altringham 2012).

Strong

preference but

not absolute

reliance (i.e. will

cross gaps if

faced with no

other option)


Rhinolophus

hipposideros

Avoids open areas, uses features such as hedgerows,

tree lines. Reliance

Data-search

5.2.6 The results of the data-search performed by WBRC demonstrate there are five

known off-site bat-roosts within average nightly foraging ranges of the site. These

are summarised at Table 9 and their location shown at Figure 6 on the following

page.

Table 9. The location of known off-site bat roosts (provided by WBRC) within

the species’ average nightly foraging range of the site.

Ref

No. (see

Fig. 6)

SPECIES ROOST TYPE

DATE OF

MOST

RECENT

RECORD

LOCATION

DISTANCE

FROM

SITE

1 Noctule

Nyctalus noctula

Transit roost

(1 bat) 25/07/2013 SO887452

4.43 km

north-west

2

Common

pipistrelle

Pipistrellus

pipistrellus

Probable

maternity roost

(1 lactating

female)

20/07/2010 SO83998 44478

(Cliffey Wood)

2.21 km

north-west

3

Unknown roost

type

(4 bats)

26/06/2009

SO882429

(Dunstall

Castle)

2.9 km west

4

Probable

maternity roost

(17 bats)

08/06/1997 SO865404 1.42 km

south-east

5

Brown long-eared

bat

Plecotus auritus

Unknown roost

type

(droppings alone)

12/02/2007 SO854406 0.69 km

south

5.2.7 In addition, the results of roost truthing suggested 19 on-site trees held PRF.


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Figure 6. The location of known off-site bat roosts (provided by WBRC) in

relation to the site, stratified to include only those roosts within the typical

nightly foraging range of the species. Reference numbers refer to those in Table

9.

5.2.8 Reference to Ordnance Survey 1.25,000 mapping and satellite imagery suggests that

there are no impassable barriers that would prevent bats in off-site roosts 1 through 5

from visiting the site.

Commuting habitat desk-study conclusion

5.2.9 The site holds four linear landscape elements comprising combinations of

waterways and ditches, hedgerows, fences and tracks and roads that might be

exploited by commuting bats including those known to occupy off-site roosts and

any that might be present within on-site PRF.

5.2.10 Of the species occurring in Worcestershire, three species are reliant or show a strong

preference for commuting within the shelter afforded by linear landscape elements

comprising Bechstein’s bat, brown long-eared bat and lesser horseshoe bat. A

further eight species show a preference for linear landscape elements comprising

barbastelle, serotine, Brandt’s bat, Daubenton’s bat, whiskered bat, Natterer’s bat,

common pipistrelle and soprano pipistrelle. Furthermore, roosts of three of these


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species are known to occur outside the site, but within their average nightly foraging

range.

5.2.11 As the linear landscape elements identified may be lost, damaged or their integrity

degraded (i.e. by indirect effects) as a result of the development, truthing of the

desk-study results was therefore recommended.

5.3 Commuting habitat truthing

5.3.1 In order to truth the hypothesis that linear landscape elements that will be lost,

damaged or have their integrity degraded might be exploited by bats occurring in the

County (in particular those colonies knowns to be present in off-site roosts, or that

might exploit suitable on-site PRF), the network of linear landscape elements within

the site was qualitatively assessed using the results of the Phase 1 survey and

characterised as follows:-

Negligible value – No bat commuting potential due to discontinuity and/or

isolation (remnant hedge sections, post and wire fence etc.);

Low value – Limited commuting potential due to lack of connectivity at one end

resulting in a greater than 30 m gap and/or on average 1 m height or less;

Moderate value – Above 1 m height, but suboptimal structure and with one or

more wide gaps (i.e. 10 m or greater); or

High value – Above 1 m height, dense structure, continuity with hedges in the

wider locality and no gaps greater than 10 m wide.

5.3.2 Figure 7 on the following page shows the results of the mapping of linear landscape

elements. Those judged to be of negligible value are not shown. Those judged to be

of low value are shown in red, those of moderate value shown in orange and those of

high value shown in green.

5.3.3 The likely effect of the loss of the linear landscape elements that were judged to be

of moderate and high value to bats known to be present in off-site roosts and

potentially present in suitable PRF was assessed by:-

1. Using the data-search results to identify the species occurring in the County and

the nearest known colonies of each of those species in range of the site that are

known to exhibit a preference for following linear landscape elements when

commuting;

2. Whether, from reference to O.S. and satellite imagery it is probable that any

identified roosts currently have connectivity with a network of linear landscape

elements that include those in the site;

3. What increase in distance bats, and in particular those occupying known roosts,

would have to travel as a result of the development; and

4. Whether (and to what extent) this would be likely to result in a certain (i.e.

specific), identifiable and real obstruction, sufficient to affect the survival

chances, breeding success or the reproductive ability of bats occupying known

roosts and potentially suitable PRF, or lead to a reduction in the occupied area.

5.3.4 Reference to O.S. and satellite imagery indicated that roosts holding common

pipistrelle and brown long-eared bat (Roost Ref. Nos. 4 and 5 respectively) currently


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have connectivity with a network of linear landscape elements that connect with

those in the site.


Figure 7. The results of truthing of linear landscape elements within Ryall

North for their potential to be exploited by roosting bats. High potential

commuting routes (shown in green), moderate potential commuting routes

(shown in orange) and low potential commuting routes (shown in red).

5.3.5 The distance bats currently travel to cross the site via the existing moderate and high

value linear landscape elements, and the distance they would have to travel in the

absence of those features, was calculated and the results provided at Table 10 and

Figures 8 and 9 on the following pages.

Table 10. The distances bats have to travel to cross the site from east/west

currently (i.e. via the network illustrated in Figure 8), during the development

(i.e. via the network illustrated in Figure 9).

START END

LENGTH OF BEST

ROUTE BEFORE

DEVELOPMENT

LENGTH OF BEST ROUTE AS

A RESULT OF

DEVELOPMENT IN THE

ABSENCE OF MITIGATION

DIFFERENCE

A B 322 m 322 m Nil

A C 565 m 618 m +53 m

A D 618 m 1,476 m +858 m

A E 1,026 m 1,884 m +858 m

A F 1,565 m 2,551 m +986 m


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START END

LENGTH OF BEST

ROUTE BEFORE

DEVELOPMENT

LENGTH OF BEST ROUTE AS

A RESULT OF

DEVELOPMENT IN THE

ABSENCE OF MITIGATION

DIFFERENCE

B C 243 m 243 m Nil

B D 296 m 1,798 m +1,502 m

B E 704 m 2,206 m +1,502 m

B F 1,243 m 2,206 m +963 m

C D 592 m 2,094 m +1,502 m

C E 502 m 2,885 m +2,383 m

C F 1,000 m 1,986 m +986 m

D E 408 m 408 m Nil

D F 1,085 m 1,085 m Nil

E F 677 m 677 m Nil

Figure 8. The current network of linear landscape elements and barriers to

commuting bats within the site and a 500 m radius of the application site

boundary. High quality elements are shown as a green line, moderate quality as

an amber line, and poor quality as a red line.

5.3.6 Reference to Table 10 and Figures 8 and 9 demonstrates that if the linear landscape

elements of moderate and high value within the site were rendered unsuitable for

commuting bats as a result of the development, the bats present would have to travel

a minimum additional distance of c. 1.8 km (1,798 m) and a maximum additional

distance of c. 2.4 km (2,383 m) in order to cross the development east to west via

linear landscape elements, but no additional distance from north to south.


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Figure 9. The network of linear landscape elements and barriers to commuting

bats within the site and a 500 m radius of the application site boundary minus

the maximum severance that will result from the proposed development. High

quality elements are shown as a green line, moderate quality as an amber line,

and poor quality as a red line.

5.3.7 Based on the assessment thus far performed, the effect of the loss of linear landscape

elements will result in a certain (i.e. specific), identifiable and real impact. However,

the scale of this impact, insomuch as it might result in a disturbance effect

potentially sufficient to affect the survival chances, breeding success or the

reproductive ability of bats occupying known roosts and potentially suitable PRF, or

lead to a reduction in the area occupied by a local bat population of any species,

cannot be determined on the basis of the assessment thus far performed.

Commuting/migrating habitat truthing conclusion

5.3.8 Truthing was performed on 23rd

, 24th

, 29th

& 30th

April 2014 (during the Phase 1

(JNCC 2010) habitat survey) and concluded that no moderate but three high

potential linear landscape elements that may be exploited by bats present in known

off-site roosts and potentially suitable on-site PRF, will be lost as the result of the

development. These are shown at Figure 9. Although the hedges in the south of the

site (particularly those on the south-west) are subject to more intensive management

than those dividing the tillage, the combined severance will result in bats present

having to travel a minimum addition distance of c. 1.8 km and a maximum


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additional distance of c. 2.4 km to circumnavigate the site. The development will

therefore have a certain (i.e. specific), identifiable and real risk of disturbance to

local bat populations that might impair the ability of local bat populations to breed,

reproduce, rear their young or migrate; or affect the local distribution and abundance

of two bat species.

5.3.9 Commuting/migrating habitat survey would be proportionate to the level of risk and

was therefore advocated.

5.4 Commuting/migrating habitat survey rationale

5.4.1 The survey method(s) chosen should be appropriate to achieve the objective of

establishing whether the linear landscape element is an important commuting-route

for species known to occupy roosts in the locality and if so, to provide sufficient

information to support derogation under licence by demonstrating how the “…action

authorised by the licence would not be detrimental to maintaining the population of

the species concerned at a favourable conservation status in its natural range.”

5.4.2 In accordance with case law (Morge v Hampshire County Council):-

A species-by-species approach should be taken as different species will react



Greater emphasis should be given to actions that might affect breeding, rearing,

hibernation and migration8;

Consideration should be given to the rarity and conservation status of the species



the latter may be more numerically abundant in that particular site). Therefore,

thought should be given to assigning the value of the linear landscape elements

at a geographic scale, such as that defined by Wray et al. (2010); and

Greater emphasis should be attached to species that are declining in numbers




constraints inherent to them are described. In addition, site-specific constraints are

identified, and how they were ameliorated is described.

6. FORAGING HABITAT ASSESSMENT


6.1.1 The path to a physical survey of a site for foraging habitat should logically follow

the following three-stage progression:-

8 As set out under Article 12(1)(b) of the Habitats Directive which prohibits “deliberate disturbance of [EPS],



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1. Desk-study:- a. Identify which habitats within the site might represent foraging habitat to

bat species known to occur in the County, and in particular colonies

known to occur within range of the site and those potentially present

within on-site PRF;

b. Establish whether and to what extent the habitat within the site will be

lost as a result of the development;

c. Assess whether this can be predicted to result in certain (i.e. specific),

identifiable an real harm to the species potentially present, and in

particular whether the loss of habitat will be significant to any identified

on or off-site colonies; and

d. If certain (i.e. specific), identifiable and real harm sufficient to impair the

ability of a local population of any bat species to survive, mate, rear

young, hibernate and/or migrate, or to significantly affect the local

distribution or abundance of any species cannot be confidently

demonstrated, then the assessment may cease at this stage. If

superficially suitable habitat is present and a certain risk of harm is

confidently identified, the assessment should progress to Stage 2.

2. Truthing:- a. Assess whether or not the habitat is of genuinely suitable quality to be

exploited by the pertinent species; and

b. If the habitat is found upon close inspection to be unsuitable then the

assessment may cease at this stage. If the habitat is suitable the

assessment should progresses to Stage 3.

3. Survey:- a. Design and perform a survey that will confidently assess whether the

habitat is exploited for foraging by the pertinent species, and what

geographical level of value (i.e. Local, County, Regional, National of

International) the habitat/suite of habitats represent9; and

b. If no such survey is possible, or proportionate to the level of risk, identify

this and conclude on the basis of the data available.

6.2 Foraging habitat desk-study

Habitat assessment

6.2.1 In broad terms, different species of bats have different hunting strategies and favour

different sorts of invertebrate prey; therefore foraging in different habitats or, if the

same habitat, at different altitudes. To further complicate the matter, some species

exhibit seasonal variations in the habitats they exploit, and also exhibit temporal

variations in the intensity of their foraging activity over the course of a single night.

Finally, it should be borne in mind that different species emerge from their roosts at

different intervals before and after sunset, and may therefore arrive at the same

habitat parcel at different periods during the same night.

6.2.2 In order to define the potential dependent bat fauna of the site, Table 11 on the

following page sets out the foraging habitat preferences typically exhibited by



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Worcestershire’s 14 bat species in terms of their closest matching Phase 1 habitat

types.

Table 11. The typical habitat preference of Worcestershire’s 14 bat species, as

described in Entwistle et al. (2001), Harris & Yalden (2008) and Dietz et al.

(2011).


HABITATS

HABITAT

PRESENT IN

SITE

Barbastelle

Barbastella barbastellus

Broadleaved semi-natural and riparian woodland.

A1.1.1 Broadleaved semi-natural woodland

Habitat Present: No

Serotine

Eptesicus serotinus

Woodland edge, orchards, parkland, pasture, meadows and hedges.


woodland (edge)

A1.1.2 Broadleaved plantation woodland (orchard)

A3 Parkland/scattered trees B2.1 Neutral unimproved

grassland (cattle pasture &

meadow) J2.1 Intact hedge



Bechstein’s bat

Myotis bechsteinii

Deciduous woodland, orchards,

parkland and hedgerows with mature trees (last in autumn only).


woodland A1.1.2 Broadleaved plantation

woodland (orchard)


Habitat Present:

Yes

Brandt’s bat

Myotis brandtii

Broadleaved, coniferous and mixed

woodland, moorland and hedges.

A1 Woodland

B1 Acid grassland B5 Marshy grassland

D Heathland

E Mire J2.1 Intact hedge

J2.2 Defunct hedge


Habitat Present:

Yes

Daubenton’s bat

Myotis daubentonii

Still or slow-moving fresh water,

woodland close to water, meadows

and orchards.

G1 Standing water

G2 Running water (slow-moving)

in association with:

A1 Woodland A1.1.2 Broadleaved plantation

woodland (orchard)

B2.1 Neutral unimproved grassland


Whiskered bat

Myotis mystacinus

Woodland, glades, coppice,

meadows, waterbodies, flowing water and hedgerows.

A1 Woodland



G1 Standing water

G2 Running water J2.1 Intact hedge


Habitat Present:

Yes

Natterer's bat

Myotis nattereri

Broadleaved, coniferous and

riparian woodland, orchards,

parkland, open arable fields, improved grassland and tree-lined

river corridors.

A1.1 Broadleaved woodland

A1.1.2 Broadleaved plantation

woodland (orchard) A1.2 Coniferous woodland


B2.1 Neutral unimproved grassland (cattle pasture &

meadow)

& combinations of:

G2 Running water (river)




Habitat Present:

Yes


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HABITATS

HABITAT

PRESENT IN

SITE

Leisler’s bat

Nyctalus leisleri

Woodland, scrub, parkland, pasture (cattle grazed), improved grassland,

lakes, canals, rivers and amenity

grassland.

A1 Woodland A2 Scrub


B Grassland and marsh (grazed) B2.1 Neutral unimproved

grassland (cattle pasture &

meadow) G1 Standing water (lake or canal)


J1.2 Amenity grassland

Habitat Present:

Yes

Noctule

Nyctalus noctula

Woodland, riparian woodland,

pasture, meadows, and still or slow-

moving water.

A1.1 Broadleaved woodland B2.1 Neutral grassland

(cattle pasture)

G1 Standing water G2 Running water (slow-moving)



Pipistrellus nathusii

Broadleaved and mixed woodland, tree lines or parkland near water,

wet woodland,

lakes and rivers.


woodland (wet)

& combinations of:


A1.3 Mixed woodland A3 Parkland/scattered trees



G1 Standing water

G2 Running water

G1 Standing water (lake) G2 Running water (river)

Habitat Present:

Yes

Common pipistrelle


Deciduous woodland, coniferous

and mixed plantation, tree lines,

unimproved grassland, improved pasture, lakes and rivers.


A2.2 Coniferous plantation woodland

A1.3.2 Mixed plantation

woodland A3 Parkland/scattered trees

B1.1 Acid unimproved grassland


B3.1 Calcareous unimproved

grassland

B4 Improved grassland (pasture)

G1 Standing water (lake)

G2 Running water (river) J2.1 Intact hedge

J2.2 Defunct hedge


Habitat Present:

Yes

Soprano pipistrelle


Broadleaved semi-natural

woodland, riparian woodland,

parkland, tree lines, lakes and rivers.


woodland

A3 Parkland/scattered trees G1 Standing water (lake)


J2.1 Intact hedge J2.3 Hedge and trees

Habitat Present:

Yes


Plecotus auritus

Deciduous, mixed and plantation

woodland. Tree lines, and hedges

with mature trees.


A1.2 Coniferous woodland

A1.3 Mixed woodland A1.3 Mixed woodland (edge)





Rhinolophus

hipposideros

Deciduous woodland.


woodland

within network of

J2.1 Intact hedge or


Habitat Present:

No

6.2.3 The review of the foraging habitat preferences of Worcestershire’s 14 bat species,

demonstrates that the site might be exploited by 12 species, comprising:-

1. Serotine – A3 Parkland/scattered trees (c. 0.6 ha) and J2.1 Intact hedge (c. 2220

m);


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2. Bechstein’s bat – A3 Parkland/scattered trees (c. 0.6 ha);

3. Brandt’s bat – J2.1 Intact hedge (c. 2220 m);

4. Daubenton’s bat – G1 Standing water (c. 0.07 ha) and G2 Running water (c. 820

m);

5. Whiskered bat – A3 Parkland/scattered trees (c. 0.6 ha), G1 Standing water (c.

0.07 ha), G2 Running water (c. 820 m) and J2.1 Intact hedge (c. 2220 m);

6. Natterer’s bat – A3 Parkland/scattered trees (c. 0.6 ha) and G2 Running water (c.

379 m);

7. Leisler’s bat – A2 Scrub (c. 0.2 ha), A3 Parkland/scattered trees (c. 0.6 ha), B2.2

Neutral semi-improved grassland (c. 5.45 ha), B4 Improved grassland (c. 10.65

ha) and G2 Running water (c. 379 m);

8. Noctule – B2.2 Neutral semi-improved grassland (c. 5.45 ha), G1 Standing water

(c. 0.07 ha) and G2 Running water (c. 820 m);

9. Nathusius’ pipistrelle – A3 Parkland/scattered trees (c. 0.6 ha), G1 Standing

water (c. 0.07 ha) and G2 Running water (c. 820 m);

10. Common pipistrelle – A3 Parkland/scattered trees (c. 0.6 ha), B4 Improved

grassland (c. 10.65 ha), G2 Running water (c. 379 m) and J2.1 Intact hedge (c.

2220 m);

11. Soprano pipistrelle – A3 Parkland/scattered trees (c. 0.6 ha), G2 Running water

(c. 379 m) and J2.1 Intact hedge (c. 2220 m); and

12. Brown long-eared bat – A3 Parkland/scattered trees (c. 0.6 ha).

6.2.4 The results of the data-search performed by WBRC demonstrate that of the 12

species that might exploit the site for foraging, five known off-site bat-roosts of

noctule, common pipistrelle and brown long-eared bat exist within their average

nightly foraging range of the site. These are summarised at Table 9 and their

location shown at Figure 6. Reference to Ordnance Survey 1.25,000 mapping and/or

satellite imagery suggests that there are no impassable barriers that would prevent

bats occupying off-site roosts from visiting the site and potentially exploiting the

following habitats:-

0.6 ha of A3.1 – Woodland and scrub / Parkland/scattered trees / Broadleaved,

potentially exploited by:-

o Common pipistrelle from Roost Ref. Nos. 2, 3 & 4; and

o Brown long-eared bat from Roost Ref. No. 5.

5.45 ha of B2.2 – Grassland and marsh / Neutral grassland / Semi-improved,

potentially exploited by:-

o Noctule from Roost Ref. No. 1; and

o Common pipistrelle from Roost Ref. Nos. 2, 3 & 4.

10.65 ha of B4 – Grassland and marsh / Improved grassland, potentially

exploited by:-


0.07 ha of G1.1 – Open water / Standing water / Eutrophic, potentially exploited

by:-



820 m of G2 – Open water / Running water, potentially exploited by:-



2,220 m of J2.1.1 – Miscellaneous / Boundaries / Intact hedge / Native species-


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rich, potentially exploited by:-


6.2.5 Of the above habitats, six habitats comprising A3.1, B2.2, B4, G1.1, G2 and J2.1.1

will be lost, damaged or their integrity degraded (i.e. by indirect effects) as a result

of the development. In order to assess the potential effects of the loss of these areas

upon the known local bat colonies, further reference was made to Ordnance Survey

1.25,000 mapping and satellite imagery in order to assess whether the surface area of

the habitat that will be lost represents a significant proportion of the habitat available

to the identified off-site colonies.

6.2.6 To date the surface area of suitable habitat required to sustain specific colony types

of specific bat species is unknown. The question is therefore whether the loss to

each colony is sufficiently significant to trigger the need for survey in order to either

support an application for derogation under licence, or to demonstrate that such a

licence will not in fact be needed. In order that the impact assessment is objective,

some other interpretation of significance is therefore required.

6.2.7 In statistical terms, significant is an outcome which is predicted to occur in less than

1 in 20 cases. By definition this would be an outcome that occurred less than 5% of

the time. In more basic terms, the Oxford English Dictionary (Soanes et al. 2005)

defines significant as “important or large enough to have an effect or be noticed.” In

the context of EcIA, and in the absence of a scientific account, one might therefore

interpret a significant habitat area as one that represented more than 5% of that

available to a specific colony. In the absence of any accepted threshold, 5% was

chosen as the significance threshold.

6.2.8 In order for there to be a significant effect upon the noctule colony present in Roost

Ref. No. 1, there would have to be less than 109 ha (95%) of semi-improved

grassland, and less than 1.33 ha of open water remaining to the colony. In fact there

is well over this area remaining.

6.2.9 In order for there to be a significant effect upon the common pipistrelle colony

present in Roost Ref. No. 2, there would have to be less than 11.4 ha of scattered

trees, 109 ha of semi-improved grassland, 202 ha of improved grassland, 1.33 ha of

open water and 42 km of hedge remaining to the colony. In fact there is well over

this area remaining. The same is also true of the colonies known to be present in

Roost Ref. Nos. 3 and 4.

6.2.10 In order for there to be a significant effect upon the brown long-eared bat colony

present in Roost Ref. No. 5, there would have to be less than 11.4 ha (95%) of

wooded habitat remaining to the colony. In fact there is well over this area

remaining.

Foraging habitat desk-study conclusion

6.2.11 The site holds six habitats, comprising A3.1 (c. 0.6 ha), B2.2 (c. 5.45 ha), B4 (c.

10.65 ha), G1.1 (c. 0.07 ha), G2 (c. 820 m) and J2.1.1 (c. 2220 m) that might be

exploited as foraging habitat by 12 species of bat known to occur in the County.


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Whilst colonies occupying known off-site roosts may visit the site to forage there

are no grounds to suggest the loss of habitats within the site would represent a

significant proportion of the overall resource available to them. However, truthing of

the desk-study results was recommended in order to assess the habitat quality and

further inform the true potential for a negative impact sufficient to represent

unacceptable disturbance on all bat species potentially present.

6.3 Foraging habitat truthing

6.3.1 In order to truth the hypothesis that habitats within the site that will be lost, damaged

or have their integrity degraded might be likely to result in certain (i.e. specific),

identifiable and real harm to any individual species of bat sufficient to impair the

ability of a local population of any bat species to survive, mate, rear young,

hibernate and/or migrate, or to significantly affect the local distribution or

abundance of any species the habitats present were qualitatively assessed for:-

1. Their structure and plant species diversity; and

2. The management (land-use).

Structure and plant species diversity

6.3.2 The more natural the habitat structure and the greater the plant species diversity, the

greater the prey species diversity for bats. This characteristic may be important in

several habitats such as grassland and hedgerows (for example, serotine, Natterer’s

bat, Leisler’s bat, noctule, grey long-eared bat and greater horseshoe bat favour

unimproved grassland and not improved grass leys).

Management

6.3.3 It is often helpful to consider whether or not the management is sympathetic to

biodiversity (even unintentionally), or solely for a purpose that is at odds with

biodiversity. Consideration should take into account whether the habitat is artificial

or semi-natural, whether it involves the introduction of another organism; cows (best

for bats); sheep (a poor second); horses (of no value), game birds (also predate

invertebrates and are therefore a negative factor) etc., what physical management the

habitat is subject (i.e. mowing, coppicing, burning etc.) and whether the site is

subject to the application of agrochemicals, in particular pesticides.

Foraging habitat truthing conclusion

6.3.4 Truthing was performed on 23rd

, 24th

, 29th

& 30th

April 2014 (during the Phase 1

(JNCC 2010) habitat survey) and the findings are as follows:-

The farm is organic and avoids the use of pesticides;

None of the grassland is floristically rich;

Only a small proportion of the grassland to be affected is grazed; that in the

south of the site is mown for silage; and

Hedges in the central areas of the site, dividing the tillage, are of greater height

and width and would offer overall better foraging habitat than those in the south.


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6.3.5 Whilst the loss of foraging habitats within the site was unlikely to be significant, the

potential presence of roosting bats in trees adjacent to the grassland in the north-east

and south of the site meant that, were a colony present, the loss of these habitats

might also represent a likely risk of harm to those bats, even if the trees themselves

were retained.

6.3.6 Survey was considered proportionate to the level of risk and was therefore

advocated.

6.4 Foraging habitat survey rationale

6.4.1 The survey method(s) should be chosen to achieve the objective of establishing

whether the habitats within the site are important foraging grounds for species

known to occupy roosts in the locality and if so, to provide sufficient information to

support derogation under licence by demonstrating how the “…action authorised by

the licence would not be detrimental to maintaining the population of the species

concerned at a favourable conservation status in its natural range.”

6.4.2 In accordance with case law (Morge v Hampshire County Council):-

A species-by-species approach should be taken as different species will react



Greater emphasis should be given to actions that might affect breeding, rearing,

hibernation and migration10

;

Consideration should be given to the rarity and conservation status of the species



the latter may be more numerically abundant in that particular site). Therefore,

thought should be given to assigning the value of the linear landscape elements

at a geographic scale, such as that defined by Wray et al. (2010); and

Greater emphasis should be attached to species that are declining in numbers




constraints inherent to them are described. However, it is vital that the any site-

specific constraints are also identified, and how they will be ameliorated is

described.

7. THE SURVEY TEAM

7.1 General

7.1.1 The survey was designed by Henry Andrews MSc CEcol MCIEEM (Natural

10

As set out under Article 12(1)(b) of the Habitats Directive which prohibits “deliberate disturbance of [EPS],



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England bat licence No. CLS00414). Individual aspects of the survey were

performed by Henry Andrews, Leanne Butt BSc MSc ACIEEM, Louis Pearson BSc

MSc GradCIEEM, Katherine Murkin BSc MCIEEM and Carrie White BSc

GradCIEEM, and assisted, where appropriate, by Christy Tolliday BSc MSc.

7.2 Statements of authority

Henry Andrews MSc CEcol MCIEEM

7.2.1 Henry Andrews is the AEcol Principal Ecologist with competence in botanical and

faunal surveys. In addition to a Master’s Degree in Biological Recording and

Species Identification, he holds a licence to survey for all bat species in England and

is a Chartered Ecologist and full member of the CIEEM. Henry has 12 years’

experience of conducting Ecological Impact Assessments (EcIA) from Preliminary

Ecological Appraisal through to successful application. He has designed successful

EPS Development Licences in respect of the genus and species as set out, which

included habitat creation, species translocation and post-development monitoring

spanning 5, 10, 15 and 25 years plus. Henry holds a CS38 licence for arboreal

climbing and aerial rescue in order to survey for bats, has been contracted to appear

as an expert witness regarding bats at Public Enquiry. He is the author of the Bat

Tree Habitat Key (Andrews et al. 2013) and in this capacity has given training in bat

ecology on behalf of the Bat Conservation Trust and to the Forestry Commission.

Leanne Butt BSc MSc ACIEEM

7.2.2 Leanne Butt is the AEcol Senior Ecologist with a Bachelor’s Degree in Zoology and

a Master’s degree in Wildlife Management and Conservation. Leanne is an

Associate member of the CIEEM and has three years’ experience of conducting

EcIA from Preliminary Ecological Appraisal through to successful application. In

addition, she is competent in site assessment and a wide range of ecological surveys

and sampling analysis, including bat survey.

Louis Pearson BSc MSc GradCIEEM

7.2.3 Louis Pearson is an AEcol Ecologist with a Bachelor’s Degree in Marine Biology

and a Master’s Degree in Ecology and Management of the Natural Environment.

Louis is a Graduate member of the CIEEM and is competent in a wide range of

ecological surveys and sampling analysis, in particular bats, for which he holds a

licence to survey for all bat species in England (licence granted post Ryall North), as

well as a NPTC City & Guilds CS38 licence for arboreal climbing and aerial rescue.

Louis has competence in Phase 1 (JNCC 2010) habitat surveys, and is building up a

well-rounded range of experience of tree and woodland surveys for protected

species.

Katherine Murkin BSc MCIEEM

7.2.4 Katherine Murkin is an AEcol Ecologist with a Bachelor’s Degree in Environmental

Biology. Katherine is a Full member of the CIEEM and she is competent in site


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assessment and a wide range of ecological surveys and ultrasound analysis,

including bats.

Carrie White BSc GradCIEEM

7.2.5 Carrie White is an AEcol Ecologist with a Bachelor’s Degree in Ecology and

Biogeography. Carrie is a Graduate member of the CIEEM and is competent in a

wide range of ecological surveys and sampling analysis, in particular bats, for which

she holds a licence to survey for all bat species in England (licence granted post

Ryall North).

Christy Tolliday BSc MSc

7.2.6 Christy Tolliday is an ecologist with a Bachelor’s Degree in Biology and a Master’s

Degree in Conservation and Biodiversity. Christy is competent in a wide range of

ecological surveys and sampling analysis, including bats.

7.3 CIEEM Code of Professional Conduct

7.3.1 Permanent members the AEcol team who work under their own initiative are

required to demonstrate competency by membership of the Chartered Institute of

Ecology and Environmental Management (CIEEM). This compels surveyors to

comply with the Code of Professional Conduct, which states:

“As a member of CIEEM I shall:

i. Uphold the reputation of the profession;

ii. Maintain and develop my professional knowledge and skills and work

normally within my sphere of competence;

iii. Seek advice and assistance if I am involved in topics outwith my sphere of

competence;

iv. Ensure I exercise sound professional judgement when I provide information

and advice, applying objectivity11

, relevance, accuracy, fairness and

impartiality in the provision of such information and advice, whilst

complying with all laws and regulations;

v. Accept responsibility12

for my actions and decisions;

vi. Uphold professional integrity13

whilst maintaining the highest standards of

ethical conduct14

;

vii. Conduct business relationships with integrity, in accordance with the

principles of free and fair competition;

viii. Make scientific data and information publicly available whenever possible,

subject to the safeguard and confidentiality of commercially-sensitive and

personal data;

ix. Promote equality of opportunity and support human rights in my

professional activities;

11

Objectivity: exhibiting facts uncoloured by feelings or opinions; not subjective. 12

Responsibility: the state of being responsible. Liable to be called to account. Capable of rational conduct. 13

Ethics: Moral uprightness and honesty. 14

Ethical conduct: Morally correct and honourable leadership and guidance.


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x. Ensure those working for me are appropriately qualified, competent and

where necessary are supervised and supported; and

xi. Undertake such continuing professional development as CIEEM shall

require.”

8. SURVEY METHODS: ROOST SURVEY

8.1 Mechanism that compels survey

Motive

8.1.1 All survey in support of planning should be triggered by a certain (i.e. specific),

identifiable and real risk, not a general hypothesis that bats are present everywhere

so all development must therefore have a negative impact; if this attitude is taken the

analysis has no framework; nothing against which to measure the survey results. In

this situation, the analysis will result in a hypothesis rather than a conclusion.

Legislatory mechanism

8.1.2 Part 3, regulation 41, paragraph (1) of the Conservation of Habitats and Species

Regulations 2010 (& as amended) states that:

A person who—

(a) deliberately captures, injures or kills any wild animal of a European

protected species,

(b) deliberately disturbs wild animals of any such species,

(c) deliberately takes or destroys the eggs of such an animal, or

(d) damages or destroys a breeding site or resting place of such an animal,


8.1.3 The offence in paragraph 8.1.2 applies regardless of the stage of the life of the bat.





or




which they belong.

8.1.5 In addition, all bat species are listed under Schedule 5 of the Wildlife & Countryside

Act 1981 (& as amended) and receive legal protection under Part 1, Section 9, sub-

section (4)(b & c) which states:


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Subject to the provisions of this Part, a person is guilty of an offence if intentionally

or recklessly—

(b) he disturbs any such animal while it is occupying a structure or place

which it uses for shelter or protection; or

(c) he obstructs access to any structure or place which any such animal

uses for shelter or protection.

8.2 Summary of key considerations

8.2.1 Part 3, regulation 41, paragraph (1), item (d) of the Conservation of Habitats and

Species Regulations 2010 (& as amended) states that:

A person who—

(d) damages or destroys a breeding site or resting place of such an animal,


8.2.2 The offence of damage or destruction of a roost is therefore an ‘absolute’ offence

that does not require any fault elements to be proved in order to establish guilt. The

potential presence of a bat roost within an area proposed for development therefore

compels survey under the guidance set out within ODPM Circular 06/2005,

regardless of whether the potential roost site is to be retained within the

development proposed or not.

8.3 Risks identified that the method is to test

Roosting bats

8.3.1 The species known to occur in Worcestershire that exploit trees (i.e. A3 Broadleaved

parkland/scattered trees and hedgerow trees) of the character present in the site for

roosting, be it for hibernation, maternity, mating and/or transitory usage are

identified in Table 12. The table is stratified according to rarity status and colonies

known to occupy roosts within range of the site are shown.

Table 12. Bat species known to occur in Worcestershire that exploit trees of the

character present in the site, stratified by rarity status and colonies known to

occupy roosts within range of the site shown.

RARITY SPECIES TREE ROOST USAGE

ROOST

KNOWN

WITHIN

RANGE

RAREST Barbastelle* Maternity, mating & transitory No

Bechstein’s bat* Maternity, mating & transitory No

RARER

Brandt’s bat Maternity, mating & transitory No

Daubenton’s bat Maternity, mating & transitory No

Natterer’s bat Maternity, mating & transitory No


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RARITY SPECIES TREE ROOST USAGE

ROOST

KNOWN

WITHIN

RANGE

RARER

Leisler’s bat Hibernation, maternity, mating

& transitory No

Noctule Hibernation, maternity, mating

& transitory Yes

Nathusius’ pipistrelle Maternity, mating & transitory No

COMMON

Common pipistrelle Hibernation Yes

Soprano pipistrelle Hibernation No

Brown long-eared bat Hibernation, maternity, mating &

transitory Yes

*Annex II Species colonies may be cited as a designated feature of a Special Area of Conservation (SAC) and receive additional protection, even in a situation where they are reliant upon habitat outside the SAC. Therefore, in a situation where a

colony of an Annex II species roosted within an SAC, but was nonetheless dependent upon habitat outside, all habitats inside

and outside the SAC might be needed in order for all the attributes of the SAC to be maintained at Favourable Conservation Status (FCS).

8.3.2 The presence of a potential two Annex II species is of significance in light of their

sensitivity to human presence, typically late emergence times and their low

echolocation call intensity.

8.4 The fundamental question the roost habitat survey is to answer

8.4.1 The fundamental question is whether or not the real risk is sufficient to require a

derogation under licence if the planning permission is to be granted.

8.4.2 In accordance with the Morge judgment, the survey must therefore establish whether

or not the development might be predicted to result in a certain (i.e. specific),

identifiable and real disturbance affect that:-

1. Reduces the survival chances of any species;

2. Reduces the breeding success of any species;

3. Reduces the reproductive ability of any species; and/or

4. Leads to a reduction in the occupied area, sufficient to adversely affect the

conservation status of the species, defined as a situation where that species is

doing sufficiently well in terms of quality and quantity and has good prospects

of continuing to do so in the future.

8.4.3 In order to answer the fundamental question, the roost habitat survey should

establish whether:-

Any of the four trees holding PRF hold a bat roost; and, if so:-

o Which species;

o In what numbers;

o When; and

o For what purpose.


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8.5 Published guidance

Natural England

8.5.1 Natural England Standing Advice Species Sheet: Bats (Natural England undated)

directs Local Authority Ecologists and ecological consultants to Hundt (2012) for

guidance in the design and performance of bat surveys.

Hundt (2012)

8.5.2 The guidance within Hundt (2012) recommends that surveys of trees begin with a

preliminary ground assessment targeting “features of trees used as bat roosts”, listed

as “Natural holes, woodpecker holes, cracks/splits in major limbs, loose bark,

hollows/cavities, dense epicormics growth, bird and bat boxes”, as well as “signs

indicating possible use by bats” which are suggested to comprise “Tiny scratches

around entry point, staining around entry point, bat droppings in, around or below

entrance, audible squeaking at dusk or in warm weather, flies around entry point,

distinctive smell of bats, smoothing of surfaces around cavity”.

8.5.3 If the preliminary roost assessment proves positive, Hundt (2012) recommends that

further presence/absence survey work is performed in May through August, as well

as potentially spring and autumn. However, the level of survey effort and timing

required is not clearly defined. Methods advocated comprise dusk emergence, pre-

dawn re-entry, backtracking or automated survey.

8.5.4 If the feature(s) could be comprehensively inspected and are judged to be unsuitable

to hold roosting bats, Hundt (2012) states “no further visits are normally required.”

However, if the assessment finds that suitable features are present, a single visit is

not normally considered sufficient (Hundt 2012). This is also the case where there is

a low level of confidence in the results (i.e. a thorough inspection of a tree was not

possible due to Health & Safety concerns meaning “signs indicating possible use by

bats” would not have been recorded in the preliminary roost assessment).

8.5.5 The level of survey effort is decided by a rudimentary and subjective (i.e. not

objective) structure-based approach which categorises trees as either ‘high roost

potential’, ‘low to moderate roost potential’, or ‘low roost potential’ without

defining what these mean15

.

8.5.6 Assuming the four trees identified as holding PRF within the Ryall North site are of

high roost potential, the minimum number of presence/absence survey visits

required comprises three dusk emergence and/or pre-dawn re-entry surveys during

May through September (optimum period May through August).

8.5.7 However, in determining survey effort where confidence is required in negative

preliminary roost assessment results, the guidance in Hundt (2012) states that:

15

It is specifically stated in the paragraph that precedes Table 8.4 which appears to illustrate the categories:

“This assessment method can be used to assess any tree for its value to bats, but is not considered appropriate

for trees affected by proposed development.” In fact this does not represent a negative as the guidance in Table

8.4 is also subjective.


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“Appropriate effort depends on the results of the preliminary roost assessment, the

site, and the variety of ... trees present, and can only be determined by expert

judgement; such judgement is difficult when the survey requirements and

circumstances are complicated.”

8.6 Conflicting evidence that contradicts published guidance: Roost survey

8.6.1 In 2007, the Bat Conservation Trust held a Mitigation Conference, the proceedings

of which were published as BCT Mitigation Conference Proceedings: University of

Leicester 25-26 April 2007 (BCT 2007b). This conference was attended by

academics and professional ecologists at the forefront of each discipline. In addition,

representatives of Non-Governmental Organisations (NGO) and several Local

Authorities were also present. The summary of the workshop dealing with surveys

of trees for roosts concluded (Page 61, paragraph 2) that:

“roosts not obvious from the ground are often found by climbing. Bats use

unexpected places – seemingly ‘unsuitable’ holes and crevices.”

Furthermore:

“Consensus: The general consensus amongst the group was that people should be

encouraged not to just use dawn and dusk surveys for trees as this is not adequate to

identify a roost. Dusk and dawn surveys are not appropriate on their own.”16

Finally:

“It was agreed that surveying trees needs highly skilled surveyors otherwise the

majority of roost sites will be missed (excepting the very obvious ones – but most are

not!)”

8.6.2 The conclusions reached in the Mitigation Conference workshop are supported by

the findings of other surveyors. For example, Kunz et al. (2009) cite Kunz &

Anthony (1996) and Hoying & Kunz (1998) in identifying direct counts of

individuals as being superior to evening emergence counts, but that “in situations

where direct access to the interior of a bat roost is precluded or inadvisable (based

on physical challenges or safety risks to observers), evening emergence counts offer

the best alternative for censusing bats.”

8.6.3 The most detailed account of the tree-roosting ecology of all UK bat species was

published in 2013 and comprised:


8.6.4 This guide sets out evidence-supported and objective methods for ground mapping

of potential bat roost trees, structure-based assessments of PRF including a

dichotomous key used to identify which bat species are known (from scientific

white-papers and photographic evidence) to exploit each feature, in each season for

16

The paragraph is presented as it is formatted in the text; bold and underlined.


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specific purposes, and methods of inspection. The guidance demonstrates, using

photographic evidence at every stage, that climb and inspect surveys are the most

effective method for establishing the presence and status of bat roosts in trees.

8.6.5 As a result of the ongoing collation of evidence, Hundt (2012) has been accepted to

be incorrect, and the updated guidance that will replace it places the correct

emphasis upon climb and inspect surveys as the primary survey method for

assessing PRF in trees (J. Collins; Head of Biodiversity (and author of the tree-

roosting chapter of the updated guidance), Bat Conservation Trust, 2015, pers.

comm., 12th

September). Furthermore, the British Standards Institute will release a

British Standard later this year which concurs with this judgement.

8.7 Generic tree-roost survey constraints

Health & Safety

8.7.1 It is sometimes the case that PRF cannot be inspected due to issues of safety, as with

features inaccessible from the ground on dead trees, or high PRF on trees in close

proximity to power-lines. This problem may be overcome from the ground or an

adjacent tree by one surveyor equipped with a 2-million candle-power torch and

another with a pair of binoculars; the first surveyor aiming the torch over the

shoulder of the observer. This method is particularly effective at dusk and will, at

the very least, show whether a cavity is discontinuous or not (H. Andrews pers.

obs.). Where this is inconclusive and the entrance cannot be adequately seen from

the ground in order to perform an evening-emergence survey, a Mechanical

Elevating Work Platform may be required. In all other situations the survey may

have to resort to evening-emergence and dawn-return surveys. However, due to the

low intensity calls and late emergence times of many tree-roosting bats the latter

method should only be used in association with a ‘Night-shot’ video camera and

infrared lighting array, when all other methods have been attempted and found to be

unsuitable.

Identification

8.7.2 Constraints to identification are apparent at two levels. First, where a sufficiently

wide angle view of the tree(s) is not achieved, ground surveys may both fail to

identify PRF in the high canopy and in situations where the entrance is located on

the upper surface of a limb. Secondly, where bats are present it may be impossible to

identify them or get a reliable count by visual inspection at a distance. This may be

overcome by habitat and environmental cues, but in some cases it may be necessary

to net the bats upon emergence for identification in the hand. However, this latter

technique is not appropriate during the periods of lactation or weaning (i.e. July

through August)

Encounter bias

8.7.3 Roost-switching behaviour and so-called ‘fission/fusion’ exhibited by tree-roosting

colonies results in a wide range of encounter bias between species, sexes and


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seasons. Tree-roosting species use a number of roosts within their home range,

which may also extend to maternity colonies, with some species transient between

as many as 50 roosts and roost changes as often as every 2-3 days not uncommon

(Dietz 1993, Frank 1994, Kerth 1998, Schorcht et al. 2002, Dense & Rahmel 2002,

Dietz & Pir 2011). Furthermore, these roosts may not be occupied every year but

sporadically, in response to outside influences such as extreme weather conditions

and prey abundance. As with identification this may (in some situations) be

overcome by habitat and environmental cues, but where maternity colonies of the

Annex II species; barbastelle and Bechstein’s bat may occur, it may be necessary to

trap and radio-track individuals in order to identify core roosting areas.

Population estimates

8.7.4 In some situations aggregations of bats are impossible to count within the roost.

Where identification has been achieved this may be overcome with an emergence-

count, but in other situations it may be necessary to net the bats upon emergence.

However, this latter technique is not appropriate during the periods of lactation or

weaning (i.e. July through August).

Breeding condition

8.7.5 In some situations the breeding condition of bats found in PRF may be inferred from

behavioural cues (i.e. mating Nyctalus spp. or Pipistrellus spp., individual females

with newborn young and aggregations of bats with dependent young); in other

situations the breeding condition may not be identifiable from visual cues alone. For

example, male Daubenton’s bats frequently form all male colonies, and male

noctules are also known to form colonies of up to 20 individuals (Dietz et al. 2011).

Where breeding condition is required it may be necessary to net individual as they

leave the roost, but, as with the constraints in relation to identification and

population estimates the welfare of the bats should be given due consideration.

8.8 Ryall North tree-roost survey method

Rationale

8.8.1 Suitable PRF were subject to repeat climb and inspect survey.

Equipment

8.8.2 PRF inspections were performed by surveyors using Ridgid micro CA300 1-4 m

fibre-optic endoscope with 17 mm, 9 mm and 6 mm diameter lenses as appropriate.

Sampling effort

8.8.3 Andrews & Gardener (2015) looked into the level of survey effort required in order

to encounter bat species roosting in trees. Following a review of tree occupancy by

bat species present in the UK, they concluded that there is no single optimum search

period and therefore PRF inspections should ordinarily be performed in winter,


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maternity season, mating and April ‘flux’ period. However, tree roost surveys

should also target the period in which bats are likely to be present within the overall

season, as defined using the structure-based approach in the truthing.

Analysis method

8.8.4 On each occasion the PRF were searched for bats and droppings. In addition, the

internal substrate was assessed searching for signs that have also been demonstrated

to be indicative of the presence of roosting bats, these comprise:-

1. Cleanliness;

2. The smoothing of the substrate resulting in rough surfaces and projections

becoming polished, bobbly or bumpy;

3. A waxy and in some cases blackened sheen to the internal substrate (from the oil

of bats fur);

4. The absence of invertebrates such as woodlice and spiders, particularly in the

apex of the PRF; and

5. A distinctive smell, comprising:-

a. A foul and unpleasant odour, not unlike grass-snake defence discharge –

indicative of Daubenton’s bats or noctules;

b. A sweet yet acrid smell, likened to broken mushrooms or burnt feathers –

indicative of Natterer’s bat; and

c. A musty odour, likened to old attics – indicative of brown long-eared

bats.

8.8.5 As Items 1, 2, 3 and 4 have also been found in PRF in which blue tits night-roost

(Andrews H own data) they are not conclusive. However, the olfactory cues appear

distinct to the various bat species (Andrews H own data), and may therefore

strengthen a hypothesis of the occupied status of a PRF and the likely species, even

in the absence of the bats themselves.

8.9 Survey dates and personnel

8.9.1 Repeat climb and inspect surveys were performed by Henry Andrews MSc CEcol

MCIEEM and Louis Pearson BSc MSc GradCIEEM on 26th

August 2014, 15th

September 2014 and 16th

December 2014.

8.10 Site-specific constraints

8.10.1 When the four trees are in leaf, the PRF they hold are only visible from the ground

in two of the situations. This was however not a constraint in practice as the climb

and inspect method achieves close proximity.

8.10.2 Due to the timing involved within the project, no April visit was made. However, as

Andrews & Gardener (2015) acknowledged, this period is sub-optimal for surveys.

In particular the Myotis spp. do not occupy trees in with any frequency until mid-

May, due to the bats returning to subterannean hibernation sites on a moderately

regular basis.


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8.11 Interim conclusion

8.11.1 The methods, equipment, survey effort, season and weather conditions all satisfy or

optimum thresholds. The survey performed took account of scientific evidence and

significant surveyor experience to achieve a robust data-set that could be

meaningfully analysed to achieve the objective of assessing the risk that the

development might result in a breach of European Legislation in relation to

disturbance of EPS, potentially requiring derogation under licence from Natural

England.

9. ROOST SURVEY RESULTS

9.1 Climb and inspect survey

9.1.1 Following the PRF truthing performed on 24th

& 25th

April and 7th

, 8th

& 10th

July

2014, the four trees judge to hold suitable PRF were re-inspected a further three

times on 26th

August 2014, 15th

September 2014 and 16th

December 2014.

9.1.2 No bats or droppings were recorded but on all occasions, a foul and unpleasant

odour, not unlike grass-snake defence discharge was evident in Tree TN10.2,

indicative of the presence of Daubenton’s bats or noctules.

9.2 Analysis

9.2.1 The internal dimensions of the PRF in Tree 10.2 (which is also provided at

Appendix B) were: internal height 185 mm; and internal width 35 mm. The average

dimensions of an adult Daubenton’s bats and noctules are provided at Table 13.

Table 13. Daubenton’s bat and noctule dimensions. Measurements derived

from live and dead specimens and accounts in Dietz et al. 2011.

SPECIES LENGTH (top of head to rump) WIDTH (wrist to wrist)

Daubenton’s bat 45-55 mm 23-28 mm

Noctule 60-82 mm 28-38 mm

9.2.2 The nature of the PRF is that it tapers towards the apex. Therefore, even considering

the capacity in terms of bat of the minimum adult size, the length and width

dimensions would suggest a maximum capacity of four Daubenton’s bats or three

noctules. It is however more probable that the feature is occupied by an individual

bat of either species or individuals of both species on different dates. The roost was

not occupied in September, which it is probable it would have been had it been a

mating roost. It is therefore classified as a sporadically occupied transit roost, and

concluded to be of only low conservation significance.


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10. SURVEY METHODS: COMMUTING/MIGRATION & FORAGING

HABITAT SURVEY

10.1 Mechanism that compels survey

10.1.1 Taking the disturbance legislation in isolation, Part 3, regulation 41, paragraph (1),

item (b) of the Conservation of Habitats and Species Regulations 2010 (& as

amended) states:

A person who deliberately disturbs wild animals of any such species is guilty of an

offence.





or




which they belong.

10.2 Summary of key considerations

10.2.1 Following the review of the legislation and planning policy performed by the

Supreme Court and set out at Section 3 of this report, chiroptologists and even

general ecologists can take away three fundamental points:-

1. That the survey is should be demonstrably and undeniably necessary for obvious

reasons;

2. That the methods advocated should be proven to be effective; and

3. That the survey should be specifically designed to suit the individual

circumstances.

10.3 Risks identified that the survey is to test

Commuting/migrating bats

10.3.1 The species known to occur in Worcestershire that exploit linear landscape elements

of the character present in the site for commuting/migration are identified in Table

14 on the following page. The table is stratified by rarity status and colonies known

to occupy roosts within range of the site are shown.

10.3.2 The presence of a potential three Annex II species is of significance in light of their

sensitivity to human presence, typically late emergence times and their low



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Table 14. Bat species known to occur in Worcestershire that exploit linear

landscape elements of the character present in the site stratified by rarity

status, and colonies known to occupy roosts within range of the site shown.

RARITY SPECIES RELIANCE ON LINEAR FEATURES

ROOST

KNOWN

WITHIN

RANGE

RAREST Barbastelle* Preference but not reliance No

Bechstein’s bat* Reliance No

RARER

Serotine Preference but not reliance No

Brandt’s bat Preference but not reliance No

Daubenton’s bat Preference but not reliance No

Whiskered bat Preference but not reliance No

Natterer’s bat Preference but not reliance No

Lesser horseshoe

bat* Reliance No

COMMON

Common pipistrelle Preference but not reliance Yes

Soprano pipistrelle Preference but not reliance No


Strong preference but not absolute reliance

(i.e. will cross gaps if faced with no other

option)

Yes

*Annex II Species colonies may be cited as a designated feature of a Special Area of Conservation (SAC) and receive

additional protection, even in a situation where they are reliant upon habitat outside the SAC. Therefore, in a situation where a colony of an Annex II species roosted within an SAC, but was nonetheless dependent upon habitat outside, all habitats inside

and outside the SAC might be needed in order for all the attributes of the SAC to be maintained at Favourable Conservation

Status (FCS).

Foraging bats

10.3.3 The species known to occur in Worcestershire that exploit habitats of the character

present in the site for foraging are identified in Table 15. The table is stratified by

rarity status and colonies known to occupy roosts within range of the site are shown.

Table 15. Foraging habitats of the bat species known to occur in

Worcestershire that exploit linear landscape elements of the character present

in the site stratified by rarity status, and colonies known to occupy roosts

within range of the site shown.

RARITY SPECIES

FORAGING HABITATS THAT

WOULD BE LOST AS A RESULT

OF THE DEVELOPMENT

ROOST

KNOWN

WITHIN

RANGE

RAREST Barbastelle* None Present No

Bechstein’s bat* A3 Parkland/scattered trees No

RARER

Serotine A3 Parkland/scattered trees

J2.1 Intact hedge No

Brandt’s bat J2.1 Intact hedge No

Daubenton’s bat Insufficient extent of G1 and G2 No


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RARITY SPECIES

FORAGING HABITATS THAT

WOULD BE LOST AS A RESULT

OF THE DEVELOPMENT

ROOST

KNOWN

WITHIN

RANGE

RARER

Whiskered bat


Insufficient extent of G1 and G2

J2.1 Intact hedge

No

Natterer’s bat A3 Parkland/scattered trees No

Lesser horseshoe bat* None Present No

COMMON

Common pipistrelle


B4 Improved grassland

J2.1 Intact hedge

Yes

Soprano pipistrelle A3 Parkland/scattered trees

J2.1 Intact hedge No

Brown long-eared bat A3 Parkland/scattered trees Yes *Annex II Species colonies may be cited as a designated feature of a Special Area of Conservation (SAC) and receive additional protection, even in a situation where they are reliant upon habitat outside the SAC. Therefore, in a situation where a

colony of an Annex II species roosted within an SAC, but was nonetheless dependent upon habitat outside, all habitats inside

and outside the SAC might be needed in order for all the attributes of the SAC to be maintained at Favourable Conservation Status (FCS).

10.3.4 The potential presence of one Annex II species is of significance in light of their

sensitivity to human presence, typically late emergence time and their low


10.4 The fundamental question the commuting/migration and foraging habitat

survey is to answer

10.4.1 The fundamental question is whether or not the real risk is sufficient to require a

derogation under licence if the planning permission is to be granted.

10.4.2 In accordance with the Morge judgment, the survey must therefore establish whether

or not the development might be predicted to result in a certain (i.e. specific),

identifiable and real disturbance affect that:-

1. Reduces the survival chances of any species;

2. Reduces the breeding success of any species;

3. Reduces the reproductive ability of any species; and/or

4. Leads to a reduction in the occupied area, sufficient to adversely affect the

conservation status of the species, defined as a situation where that species is

doing sufficiently well in terms of quality and quantity and has good prospects

of continuing to do so in the future.

Commuting/migration habitat survey

10.4.3 In order to answer the fundamental question, the commuting/migration habitat

survey should establish whether:-

There are any grounds to suggest that a local colony of any bat species is reliant

upon the linear landscape elements within the site for rearing young, breeding or

migrating.


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Foraging habitat survey

10.4.4 In order to answer the fundamental question, the foraging habitat survey should

establish whether:-

There are any grounds to suggest that a local colony of any bat species is reliant

upon the foraging habitats within the site for rearing young or breeding.

10.4.5 However, as the only potential mating sites within the site are the four PRF that

were subject to climb and inspect survey in the mating season, the need to assess

breeding is unnecessary in this aspect of the overall assessment of the site. The Ryall

North foraging habitat survey was therefore focussed to assess the situation in

relation to rearing young alone.


Survey method

10.5.1 As netting tends to underestimate species richness (O’Farrell & Gannon 1999,

MacSwiney et al. 2008), and is not recommended during the period when females

may be expected to have dependent young, it was therefore not suitable for the Ryall

North survey. Ultrasound survey was therefore used to assess the risks identified to

commuting/migrating and foraging bats.

10.6 Published guidance

Natural England

10.6.1 Natural England Standing Advice Species Sheet: Bats (Natural England undated)

directs Local Authority Ecologists and ecological consultants to Hundt (2012) for

guidance in the design and performance of bat surveys.

Hundt (2012)

10.6.2 The scale provided for assessing the value of habitats for bats provided in Hundt

(2012) is subjective. However, assessing the Ryall North site against this scale,

identifies as of medium quality. Based on the prescribed method for ultrasound

survey set out in Hundt (2012), the minimum recommended visit frequency and

timing for activity surveys in large sites (i.e. more than 15 ha in size) of medium

habitat quality comprises:-

Transect survey – One visit per transect each month during the period April

(unless weather inclement) through October (unless weather conditions are

particularly cold). At least one survey visit should comprise dusk and pre-dawn

(or dusk-to-dawn survey) within one 24 hour period; and

Automated survey – Two locations per transect on five consecutive nights each

month during the period April (unless weather inclement) through October

(unless weather conditions are particularly cold).


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10.6.3 In order to conform to the method set out in Hundt (2012) two transects would be

required on each occasion, each performed by two surveyors on eight occasions. In

addition, an arbitrary two passive monitors would have to be deployed on both

transect routes, and left to run for five consecutive nights every month from April to

October inclusive.

10.6.4 Altringham (2012) set out that “a core principle of evidence-based conservation is

that methods of assessment, management, monitoring and mitigation must be tried

and tested – they must be known to work.” The core activities in ecological

consultancy must therefore adhere to basic scientific principles (Altringham 2012).

10.6.5 The method set out in Hundt (2012) is not supported by any published white-paper,

nor is any field-test of its efficacy cited, nor is there any policy or legislative

mechanism cited that recommends this level of survey effort. This places any

member of the CIEEM considering its application in potential conflict with the Code

of Professional Conduct.

10.7 Conflicting evidence that contradicts published guidance: Ultrasound activity

survey

Transect surveys

10.7.1 Surveys in support of planning should logically fulfil two functions; provide a

species inventory (i.e. a presence/absence survey); and search for patterns in activity

that may inform assessments of effects upon bats with dependent young, mating and

migration. In the simplest terms, if there is a burst of activity in the first 1-1.5 hours

following sunset, then nothing, and then a burst of activity in the last 1-1.5 hours

preceding sunrise; this might suggest the habitat is used by commuting bats but is

not important for foraging. If however, there is a burst of activity of multiple species

in the first 1.5 hours of sunset, then a pause, but one species could be discerned

consistently over returning to the site and foraging, then leaving, but then returning

again and foraging etc. on each night, over several nights, depending upon the

species it might be inferred that the site was being used by at least one lactating

female making regular returns to the roost to suckle.

10.7.2 Transect data is only meaningful in two situations; firstly when the target is

sedentary and cannot therefore be double-counted (invertebrate surveys, reptiles

under refugia, breeding birds holding territories, bat roosts (lekking or exiting or

returning to roosts)), and secondly when the objective is to gain deeper resolution in

relation in the effects of environmental conditions at micro-site level (i.e. alterations

in the distribution of activity within homogenous habitat in relation to fluctuations in

temperature or wind). In the latter case the sampling would be best undertaken over

the course of the entire active period in order to account for other variables (in the

case of bats this might be the temporary presence of a competing species, or simply

increased activity that impacted on successful foraging (i.e. brown long-eared bats

hunt by listening for prey-generated sounds, so a large number of bats all

echolocating might have a negative impact on foraging success). Furthermore,

without environmental surveillance, also at micro-habitat scale, the data is


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meaningless. Regardless, the data would be academic and unless performed over a

long period would not suit the context of an impact assessment.

10.7.3 The transect method cannot be used to detect activity patterns. Whilst it has been

advocated in a surveillance method for woodland bats by Scott & Altringham

(2014), their objective was to define a method for establishing an inventory alone

(i.e. presence/absence), and was for use by volunteers, and effort was therefore

defined from data collected using the transect method commencing 30 minutes after

sunset and continuing for a further 90 minutes. The authors pointed out that the use

of automated passive monitors would not only reduce the number of man hours

required, but would result in increased probability of detection, stating:

“A species detected on average in only 20% of nightly surveys has a more than 95%

probability of being detected after a fortnight of monitoring. Remote monitoring

makes effective use of equipment and volunteer time, and quantity of data is not a

concern from an analysis viewpoint as it can largely be automated.”

10.7.4 The justification for transect surveys is that bats can be ‘observed’ in the early

evening while light levels permit. However, several species do not emerge until

following full dark, these include barbastelle, Daubenton’s bat, Natterer’s bat, brown

long-eared bat, grey long-eared bat, greater horseshoe bat and lesser horseshoe bat

(Jones & Walsh 2001). This was highlighted by Bontadina et al. (2002) who found

that even when lesser horseshoe bats were radio-tagged, observation was only

achieved on two occasions. Furthermore, as the greater proportion of bats appear to

use hedges as cover from avian predators, and in particular owls, for the strategy to

be successful it relies upon the bat being invisible to an organism with far superior

eyes than those of a human. The method is biased toward the common pipistrelle

which, as the name suggests, is our most common bat and of least conservation

significance. Records of commuting and foraging common pipistrelles, are rarely

informative, even when the bat can be seen. However, when encountered on a

mobile transect the observations are worthless due to the species ‘hawking’ foraging

strategy, during which individuals and small groups fly in circuits suggesting higher

numbers than are actually present, and also back and forth.

10.7.5 In fact, a Master’s thesis pre-dating Hundt (2012) and three studies published since

Hundt (2012), have demonstrated that for surveys seeking to establish which species

occur in an area, and the importance of various habitat types based on the known

distribution of species within the landscape, the transect method recommended is not

fit for purpose. These comprise:-

1. Andrews H 2010. Nightly activity patterns of bats in an area of ancient semi-

natural woodland at Asham Wood SSSI, Nr Frome, Somerset; Implications for

the timing of bat activity surveys. Dissertation submitted to The University of

Birmingham for the degree of Master of Science in Biological Recording;

2. Skalak S, Sherwin R & Brigham M 2012. Sampling period, size and duration

influence measures of bat species richness from acoustic surveys. Methods in

Ecology and Evolution 3: 490-502;

3. Stahlschmidt P & Brühl C 2012. Bats as bioindicators – the need of a

standardized method for acoustic bat activity surveys. Methods in Ecology and

Evolution 3: 503-508; and


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4. Froidevaux J, Zellweger F, Bollman K & Obrist M 2014. Optimizing passive

acoustic sampling of bats in forests. Ecology and Evolution 4690-4700.

10.7.6 In a 30-night study using two passive monitors operating throughout the hours of

darkness, 79% of activity patterns were in fact found to be multimodal (Andrews

2010). When individual species were considered separately, the activity peaks of

64% of species encountered in the June/July period were recorded in the period from

two to five hours inclusive following sunset. In the September period the proportion

of activity peaks falling beyond the two hours following sunset rose to 70% of

species encountered, but the range was higher with activity peaks recorded within

the 3rd

, 4th

, 7th

and 11th

hours following sunset (Andrews 2010). Three species;

Leisler’s bat, brown long-eared bat and greater horseshoe bat (accounting for 25% of

the total recorded) were only recorded after the two hours following dusk (Andrews

2010).

10.7.7 The findings of Stahlschmidt & Brühl (2012) are of particular note, in that the study

found that transect surveys failed to represent the heterogeneous bat activity patterns

of the UK’s commonest, most visible, and easiest to detect bat species; the common

pipistrelle, even in a simple homogenous landscape. In direct contradiction of the

method set out in Hundt (2012), their findings led them to conclude that “the

application of several stationary and automated sampling systems has the highest

potential for standardised acoustic bat surveys.” This is only common sense when it

is necessary to assess which habitats within a site are of greatest importance, as to do

this in any meaningful way each habitat should be sampled for the same length of

time (Altringham 2003) and, ideally, at the same time (i.e. on the same nights) in

order to take into account individual bats exploiting different areas at different times,

on different nights, due to differing environmental conditions (temperature, wind,

rain showers, moon phase and cloud cover etc.).

10.7.8 All four studies conclude that full night sampling is necessary to make a good

estimate of the number of species present (Skalak et al. 2012, Stahlschmidt & Brühl

2012, Froidevaux et al. 2014).

10.7.9 In summary, the recommendations of the four studies are as follows:-

1. Sample over the full night to achieve the most accurate estimate of species

richness, and to record rare species having low detection probabilities (Skalak et

al. 2012, Stahlschmidt & Brühl 2012, Froidevaux et al. 2014);

2. Sample repeatedly in different micro-habitats (Skalak et al. 2012) (i.e. woodland

gap, ground and canopy reflecting the 3-D forest space used by bats (Froidevaux

et al. 2014 and also Staton & Poulton 2012));

3. Define the number of sample locations in line with the number of habitats

(Skalak et al. 2012, Stahlschmidt & Brühl 2012, Froidevaux et al. 2014); and

4. Sample on multiple nights; 2-5 to detect the common species and potentially

more if rare species predicted from a structure-based assessment have not been

detected (Skalak et al. 2012).

10.7.10 Nevertheless, there are situations where a walked transect may add valuable

data to an unmanned matrix of passive recorders, such as:-

1. Where a large number of potential roosts exist on land outside but abutting a site


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proposed for development. However, an intensive study performed by Simon et

al. (2004), found that the most profitable times of night for transect surveys

differed between species. Of the seven relevant species described comprising

barbastelle, serotine, whiskered bat, Natterer’s bat, brown long-eared bat and

grey long-eared bat, the only species for which they recommended evening

transects is the serotine (see their summary provided in Table 47 on Page 248 of

their comprehensive account);

2. Where the site was known to hold a disproportionately high number of potential

roost sites that might be occupied for mating and it was desirable to get an

approximate count of singing male Nyctalus spp. and Pipistrellus spp. bats.

However, in this context the transect would commence no earlier than three

hours following sunset; and

3. Where the effect is upon a habitat of low value to bats generally and is bounded

by another habitat that can be predicted to be of higher value. For example, in a

situation where an area of improved silage ley that is to be lost is bounded by an

area of semi-natural woodland that is to be retained and will not be degraded in

any indirect way, an automated detector deployed in the ley might still record

calls attributable to bats foraging in the woodland and thereby overestimate the

value of the habitat to be lost. Observations are however vital in this context and

night vision would also be required.

10.7.11 However, the constraints to manned surveys will always result in a degree of

bias, not only because the bats are aware of the presence of the surveyors, but due to

a multitude of deployment constraints including the obstacle of the habitats

themselves to detection (for example, a surveyor walking along a hedge may have

only a maximum 33.3% coverage; what is flying immediately above the hedge and

on the other side may be missed).

Survey effort: number of detectors

10.7.12 The arbitrarily chosen number of passive recorders advocated by Hundt

(2012) is not supported by any scientific evidence, nor is it logical when the fact that

different species favour different broad habitats, and even different structures in the

same broad habitat type. If the different habitats are not sampled equally then their

value cannot be objectively compared even at site level.

10.7.13 It is necessary to tailor the number of detectors used on the number of

different habitats that are likely to be of value, rather than an arbitrarily chosen

figure. In some situations it may be necessary to attach greater weight to habitats

with the highest probable quality (i.e. cattle-grazed grassland above sheep-grazed, or

areas of increased plant species richness over impoverished examples of the same

broad habitat). Finally, consideration should be given to the structure of the habitat

and the way bats use it in order that sufficient detectors are used; Staton & Poulton

2012 and Froidevaux et al. 2014 demonstrated that a confident species census of a

woodland could only be achieved by deploying two detectors (one at ground level

under the canopy and another in a glade). All stratification of effort should of course

be justified using a structure-based habitat assessment supported where possible by

published science.


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Survey effort: number of nights in each sample period

10.7.14 Several studies have looked at survey effort in order to provide

recommendations. Hayes (1997) recommended six to eight nights for activity

studies, but Broders (2003) increased this to over 14, even for common species.

Froidevaux et al. (2014) reported a 90% inventory of woodland after a minimum 12

nights using three detectors stratified in combination. Skalak et al. (2012) found that

it took on average just over 20 nights to produce an 80% inventory. These high

levels of effort led Adams (2013) to investigate the use of multiple detectors, which

resulting in the conclusion that four detectors recording for a minimum of four

nights would give an accurate estimate of overall activity across a site (in

homogenous habitat) and highlighted that it is important to place multiple detectors

throughout a site in order to capture spatial variations in activity. When an

individual detector was deployed, the findings of Hayes (1997) and Adams (2013)

support each other; no less than six nights. In surveys of broadleaved woodland in

the UK, Scott & Altringham (2014) recommended that nine nights survey might be

required to detect the presence of the Plecotus spp. but all other species would be

likely to be recorded with less effort.

10.7.15 From a purely practical perspective, detectors that remain deployed over a

weekend can be predicted to have a higher chance of discovery with consequential

theft or vandalism. Such an outcome has a significant impact upon the cost of a

project (detectors may cost well over £1,000) and also its accuracy due to loss of

data.

10.7.16 In order to achieve an inventory of species, the minimum overall nine nights

recommended by Scott & Altringham (2014), appears a robust level of effort. In

terms of sample effort, as a survey to inform an impact assessment will inevitably

involve the inference of importance from patterns of activity, and activity levels can

vary wildly from one night to the next (AEcol own data). However, during the

lactation period, females return to the same favoured high-profitability foraging

grounds on each night. For example, Mackie & Racey (2007) found that lactating

noctules typically flew fast and straight to the same foraging grounds each night,

although the order and duration of these visits might vary. As a result, one night of

deployment might be predicted to detect a species foraging, but might underestimate

the true value of the habitat to that species. It is therefore sensible to deploy for

multiple nights. In most cases (as is demonstrated by the results of the Ryall North

survey) three nights is acceptable, but four nights can be predicted to represent a

robust level of effort, whilst avoiding the increased risk of incidental sabotage posed

by detectors being deployed over weekends.

Seasonal sampling

10.7.17 The issue with the excessive seasonal sampling set out in Hundt (2012) is,

again, that it is entirely unsupported by any published white-paper, or even justified

informally by a an account of a field-test. The effort is a disproportionate catch-all

that fails to take into account of what bats are actually likely to be doing at different

points in the year and therefore how reliable the data will be for assessing the value

of habitats in the context of an impact assessment.


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10.7.18 In April, bats of all species and both sexes may have emerged from

hibernation roosts entirely, but equally may not have and may be making regular

returns when temperatures are low and foraging is unprofitable. Where migrations

do occur they are a gradual trickle rather than the en-masse September movements.

Sampling in April is therefore unpredictable, and always subordinate to September

sampling against which it would logically be compared. Therefore, in the absence of

hibernacula on-site or adjacent to it, it is unlikely any meaningful number of

contacts would be achieved. Whilst the results might be academically interesting,

they are unlikely to materially affect any impact assessment. April data have never

proved helpful in any survey AEcol have performed.

10.7.19 In May and June, males and females roost apart. Whilst the number of

females roosting together increases as pregnancy progresses (with a consequential

decrease in the number of PRF occupied) the colonies are at their most mobile.

Numbers in an individual roost may fluctuate wildly, with a consequential

fluctuation in the number of bat passes recorded in individual parcels of habitat in

relation to changes to a terrific number of variables; temperature, precipitation, crop,

livestock distribution, disturbances in and around roost sites etc. Nevertheless,

Staton & Poulton (2012) found that in ancient semi-natural woodland, different

species exhibited different peaks in activity in the spring and summer periods,

suggesting May sampling in woodland would be worthwhile. However, in open

habitat the often wild fluctuations in the data mean they are often unreliable in the

context of impact assessment. Sampling in the May/June period is less conclusive

for assessing the importance of habitats to local populations and in all but the most

exceptional situations (i.e. where a site is within range of an Annex II species

occupying a Special Areas of Conservation (SAC) or Site of Special Scientific

Interest (SSSI) cited specifically for that species), the data can be predicted to

become subordinate to the results of July sampling. This is particularly pertinent to

the priorities defined by the Morge case.

10.7.20 In July, the bats have given birth and are suckling young. As a result, the

adult females have to make regular returns to the roost in the course of each nights

foraging in order to feed and warm their young. Females suckling young can be

predicted to occupy the most profitable habitats due to the increased energy demand,

and also to forage closer to the natal roost than when they were pregnant. July data

is therefore far more valuable in terms of a true impact assessment, particularly of

foraging habitat. Furthermore, although some species both commute and forage on

linear landscape elements, the usage of this habitat can be divided by looking at the

ratio of passes to feeding buzzes in order to assess the value of the habitat as those

species that do forage on hedgerows at this time exhibit both. This is of particular

importance, because although severance effects are rare, the effects brought about by

the loss of foraging habitat the hedgerows represent, may otherwise be

underestimated.

10.7.21 In August the young begin to fly, and the colonies become more mobile.

Young inexperienced bats can be predicted to be more vulnerable to avian predators

than the more mature bats in the colony, and are therefore more reliant upon the

cover of linear landscape elements for commuting. They are also learning the extent

and orientation of the colonies territory, and data captured on linear landscape


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elements in August may therefore be of greater value when assessing the importance

of such habitat to the local population of each species.

10.7.22 In September, the number of bats on the wing is at its highest, following the

birth of that year’s young, and before the inevitable winter mortalities. As colonies

begin to move back towards hibernation quarters trends valuable data can be

gathered in order to assess the value of linear landscape elements as migration

routes. In addition, Murphy et al. (2012) found that brown long-eared bats foraged

outside woodland on hedgerows in the late summer and autumn, and therefore

hedges might play an important role in the increased demands resulting from

increased colony size at this time. However, as brown long-eared bats do not

typically generate a feeding buzz (Swift & Racey 2002), inference of the importance

of hedgerows to local populations must be made from commuting contacts at this

time of year.

10.7.23 Outside woodland, foraging activity peaks are most discernible in the period

of greatest sensitivity; the lactation period, the weaning period (when newly volant

young venture further from the natal roost) and the September mating/migration

season. These are the minimum sampling periods and represent a robust survey

effort.

10.8 Generic ultrasound survey constraints

Identification

10.8.1 There has been considerable debate worldwide as to the level of confidence that can

be placed upon species identification using ultrasound detectors (Ahlen & Baagoe

1999, Barclay 1999, Corben & Fellers 2001, Fenton 2000, Fenton et al. 2001,

Kapteyn 1993, O’Farrell et al. 1999, Vaughn et al. 1997). This also applies to

species in the UK where the five Myotis spp. bats are hard to separate from one

another due to the large overlap in call structure (Briggs & King 1998, Jennings et

al. 2008, Walsh & Catto 2004). Care must be taken when assessing the calls of the

Myotis species, and the temptation to definitely identify a call to species must be

resisted where reasonable doubt exists.

Encounter bias

10.8.2 The wide ranges of echolocation intensity exhibited between individual bat species,

make it improbable that ultrasound sampling will be equal (Barclay 1999, Fenton

2003, Fenton & Bell 1981, O’Farrell & Gannon 1999) but will favour those species

with high intensity echolocation (Findley 1993). For example, the echolocation of

brown long-eared bat is so quiet that some detectors are not sensitive enough to pick

it up at all and most require the detector to be within a few feet of the bat (Briggs &

King 1998). More generally, bat detector surveys under-record species with weak

echolocation calls (Barbastella barbastellus, Myotis bechsteinii, M. nattereri and

Plecotus spp.) and are consequently biased toward loud echolocators (e.g. Eptesicus

serotinus, Nyctalus spp. and Pipistrellus spp.).


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Population estimates

10.8.3 It is generally impossible to distinguish between multiple passes made by a single

bat or several bats passing only once each (O’Farrell et al. 1999, Kalcounis et al.

1999). Indices of abundance may be used to assess relative changes, but offer little

or no information on exact colony or overall population size (Kunz et al. 2009).

Kunz et al. (2009) identified that, to date, there has been no success in converting

activity data based on echolocation calls to estimate the number of bats present, nor

for that matter yielded information on relative abundance. This is still the case in

2015. It is therefore impossible to estimate the numbers of bats of any individual

species that might be reliant upon a site for any other purpose than roosting. This

point cannot be overstressed; indices identify changes (i.e. increases or decreases)

over long periods of time, they will not estimate the number of bats that might be

reliant upon a given area of habitat, or how much habitat would be required to

support a population (Hayes et al. 2009).

Breeding condition

10.8.4 Ultrasound survey cannot distinguish the sex of the bats present, and will therefore

not give any but the roughest indication that a maternity roost might be present

(inferred from relatively high numbers of contacts within a key period of the

maternity season for that particular species).

Activity

10.8.5 Academic ultrasound activity studies of individual species have historically

classified contacts as in-flight passes and ‘feeding buzzes’; the latter denoting

successful foraging behaviour. This analysis is ineffective when considering species

which glean for prey (i.e. detect their target by prey-generated sounds). Such species

typically have very quiet echolocation and may not give any audible feeding ‘buzz’.

As a result, this behavioural characteristic cannot be used in analysis of foraging

behaviour as it will inevitably result in the underestimation of those species, several

of which are Annex II species.

10.9 Ryall North commuting/migration and foraging habitat survey method

Rationale

10.9.1 Kunz & Parsons (2009) cite various studies in a cautionary note regarding the use of

ultrasound:

“Many studies have misused acoustic monitoring techniques: they have lacked

replication, not tested clear hypotheses, not addressed spatial and temporal

variation in activity levels, and not acknowledged the limitations of the equipment.”

10.9.2 Section 1.1 of Hundt (2012) states:

“The guidance should be interpreted and adapted on a case-by-case basis,


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according to the expert judgment of those involved. There is no substitute for

knowledge and experience in survey planning, methodology and interpretation of

findings, and these guidelines are intended to support these. Where examples are

given they are descriptive rather than prescriptive.”

10.9.3 In an effort to counteract the trend identifed by Kunz & Parsons (2009), AEcol took

account of Section 1.1 of Hundt (2012) and designed the assessment of

commuting/migration and foraging habitat to satisfy the recommendations made by

Skalak et al. (2012), Stahlschmidt & Brühl (2012) and Froidevaux et al. (2014). The

decision to deviate from the advice set out by Hundt (2012) is further justified by

correspondence with Ms. Julia Hanmer; Chief Executive of the Bat Conservation

Trust, which is provided at Appendix D.

10.9.4 Following a review of the Phase 1 mapping, predictive assessment and first draft of

the restoration scheme proposed, it was judged that the greatest potential for a

negative effect at Ryall North was the severance of linear landscape elements with a

distant secondary consideration being the potential effect of foraging habitat loss in

the vicinity of potential tree-roosts in the north-east and south of the site brought

about by the loss of cattle-grazed grassland and scattered trees.

10.9.5 The evidence as set out at within this report suggests the bat species most likely to

be ‘disturbed’ by severance of commuting routes brought about by the proposed

development comprise:-

Barbastelle (Annex II) – preference for linear landscape elements and, although

no foraging habitat is present, might cross the site;

Bechstein’s bat (Annex II) – reliant upon linear landscape elements and might

enter the site to forage or simply cross it;

Lesser horseshoe bat (Annex II) – reliant upon linear landscape elements and,

although no foraging habitat is present, might cross the site;

Serotine – preference for linear landscape elements and might enter the site to

forage or simply cross it;

Brandt’s bat – preference for linear landscape elements and might enter the site

to forage or simply cross it;

Daubenton’s bat – preference for linear landscape elements and, although

foraging habitat is insufficient in extent, might cross the site;

Whiskered bat – preference for linear landscape elements and might enter the

site to forage or simply cross it;

Natterer’s bat – preference for linear landscape elements and might enter the site

to forage or simply cross it;

Common pipistrelle – preference for linear landscape elements and might enter

the site to forage or simply cross it;

Soprano pipistrelle – preference for linear landscape elements and might enter

the site to forage or simply cross it; and

Brown long-eared bat – strong preference for linear landscape elements and

might enter the site to forage or simply cross it.

Equipment

10.9.6 In order to ensure the survey did not disturb the bats commuting through the site in


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any way and thereby bias the survey result, the SM2BAT (Wildlife Acoustics Inc.,

Concord, USA) detector was chosen as a comparative analysis test performed by

AEcol17

had demonstrated the superior performance of this particular model for

detecting two of the least detectable species; brown long-eared and lesser horseshoe

bats.

10.9.7 The gain of SM2 microphones was retained at the manufacturer’s default settings

recommended for open surveys. Performance and sensitivity of SM2 recorders are

known to differ both in range and also in catchment (AEcol’s own data), and even

between the same model. Therefore, to ensure standardisation, where possible, the

same recorder was used at the same location each night. All detectors were

programmed to begin recording 30 minutes prior to sunset and to finish recording 30

minutes after sunrise.

Sampling effort

10.9.8 Passive ultrasound monitoring comprised 12 automated survey nights. This effort

has been consistently shown in analysis of accumulation curves to be adequate to

achieve a robust inventory of species in open habitat (AEcol own data). The survey

effort is above that recommended by Adams (2013) and Scott & Altringham (2014).

Season

10.9.9 In order to assess the most sensitive periods of lactation, weaning and mating, the

SM2BAT detectors were deployed in three periods for four nights in July, August

and September.

Detector locations and deployment situations

10.9.10 Sample points were selected non-randomly, drawing upon the application of

the structure-based approach used throughout the desk-study, and truthed prior to

survey. The survey effort was therefore directed to those habitats that are of value to

the target species for which there is a perceived risk of harm sufficient to potentially

warrant derogation under licence. The survey did not therefore sample the river

bank, as the wharf proposed will be unobtrusive and will not materially alter either

the foraging/commuting potential of the habitat itself, or discourage bats from

foraging and commuting over and along the River Severn.

10.9.11 Detector Locations 2, 3 and 4 (see Figure 10 on the following page) and

deployment heights were specifically chosen to assess the usage of the three primary

flight-lines that pass east/west across the site that would be severed as a result of the

proposed scheme. Detectors were deployed on mature trees centrally 1-2 m above

the hedge top in order to ensure both sides and the hedge top would be sample

simultaneously.

10.9.12 Detector Locations 1 and 5 (see Figure 10) ‘sampled’ the two areas of

foraging habitat to be lost comprising the cattle-grazed grassland habitat in the north

and the cattle-grazed parkland character grassland in the south of the site. Detector 1

17

See http://www.aecol.co.uk/Pages/67/Research--Development---Bat-detector-comparative-test.html.


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was deployed on an oak holding no PRF and Detector 5 on a pollard crack willow

Salix fragilis.

Figure 10. The locations of the passive ultrasound detectors (1-5) at Ryall North

(red line boundary): a pink dot represents a SM2 detector.

Analysis method

10.9.13 Recordings were analysed using ANALOOK sound analysis software.

Spectrograms of each recording were inspected and various attributes including the

calls peak frequency, inter-pulse interval, maximum and minimum frequencies and

call duration, along with the call ‘shape’ (changes in call frequency over time) were

measured or calculated, and where possible used to identify the call to species level

following descriptions detailed in Russ (2012). Data recorded was then used to

create a list of bat passes per sample area and per night, detailing species identity

and time of the recorded pass.

10.9.14 In order to satisfy each of the four points identified at Paragraph 10.4.2 in

relation to assessing potential disturbance effects, the ultrasound recordings were

identified to genus and, where possible, to species and each species was considered

individually.

10.9.15 Consideration was given to the reduction in the areas of habitat in which

each species was identified.

10.9.16 Greater emphasis was given to the periods in which bats might be rearing

young and breeding, as demonstrated by the months in which the detectors were

deployed.


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10.9.17 The rarity of each species, and their population trend, was identified, and

greater consideration was given to these species than the more common species.

10.10 Survey dates, personnel and weather conditions

10.10.1 The detectors were deployed by Henry Andrews and Louis Pearson BSc

MSc GradCIEEM. Sound analysis performed by Louis Pearson, Carrie White BSc

GradCIEEM Leanne Butt BSc MSc ACIEEM, Katherine Murkin BSc MCIEEM,

and Christy Tolliday BSc MSc. Table 16 sets out the date, personnel and weather for

each aspect of the ultrasound survey.

Table 16. Date, personnel and weather conditions at midnight for each aspect of

the Ryall North ultrasound survey.

DATE ASPECT

WEATHER CONDITIONS

PERSONNEL T

emp

°c

Win

d

Bft

Ra

in

mm

Clo

ud

8th

s

03/07/14

Passive

monitoring

(All detector

locations)

16 2NE 0 6 Deployment:

Louis Pearson.

Analysis:

Louis Pearson;

Leanne Butt BSc MSc

ACIEEM;

Katherine Murkin BSc

MCIEEM;

Christy Tolliday BSc MSc.

04/07/14 17 2N 0 3

05/07/14 17 3N 6 8

06/07/14 12 2NE 0 7

11/08/14 Passive

monitoring

(Detector

locations 1, 4 &

5)

13 3NE 2 1 Deployment:

Louis Pearson.

Analysis:

Louis Pearson;

Leanne Butt;

Katherine Murkin.

12/08/14 13 2NE 0 1

13/08/14 13 2NE 0 1

14/08/14 14 2E 0 4

26/08/14 Passive

monitoring

(Detector

locations 2 & 3)

15 1SW 11 5 Deployment:

Louis Pearson.

Analysis:

Louis Pearson;

Leanne Butt;

Katherine Murkin.

27/08/14 12 3SW 0 1

28/08/14 17 2NW 4 7

29/08/14 14 2NE 0 1

15/09/14

Passive

monitoring

(All detector

locations)

14 3SW 0 3 Deployment:

Louis Pearson.

Analysis:

Louis Pearson.

Leanne Butt;

Katherine Murkin;

Carrie White BSc

GradCIEEM;

Christy Tolliday

16/09/14 13 1SW 0 4

17/09/14 16 3SW 0 5

18/09/14 14 3SW 0 8

10.11 Site-specific constraints

10.11.1 The presence of cattle within the site was a constraint to the


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commuting/migration and foraging habitat survey, as manned survey (i.e. a transect

survey) would not have been appropriate based on the number of cattle present, in

addition to the level of disturbance they create.

10.12 Interim conclusion

10.12.1 The methods, equipment, survey effort, season and weather conditions all

satisfy or exceed optimum thresholds defined by scientific research and published in

peer reviewed which papers. The survey performed was therefore designed to

achieve a robust data-set that could be meaningfully analysed to achieve the

objective of assessing the risk that the development might result in a breach of

European Legislation in relation to disturbance of EPS, potentially requiring

derogation under licence from Natural England. Furthermore, the approach to all

aspects of the survey was objective and therefore complies entirely with the CIEEM

Code of Professional Conduct.

11. COMMUTING/MIGRATION & FORAGING HABITAT SURVEY RESULTS

11.1 Species inventory

11.1.1 11 species were recorded comprising:-

Serotine;

Daubenton’s bat;

Whiskered/Brandt’s bat;

Natterer’s bat;

Leisler’s bat;

Noctule;

Leisler’s bat/noctule;

Common pipistrelle;

Soprano pipistrelle;

Brown long-eared bat; and

Lesser horseshoe bat.

Whiskered/Brandt’s bat

11.1.2 The uncertain situation with regard to whiskered/Brandt’s bat is worth greater

attention. Although Brandt’s bat has been encountered commuting and foraging on

hedgerows, these encounters are more usual in wooded areas. While British studies

appear to overlook the species, on the Continent Brandt’s bats have been found to

favour old deciduous forests in particularly damp areas (Taake 1984, Boye & Dietz

2005), and it has been suggested that they are a species of woodland in its final

decay phase (Sptizenberger 2001). As a result, Brandt’s bats are seldom found far

from woodland, and the open character of Ryall North would be atypical for the

species. Furthermore, the rarity of the late decay phase, even within an already rare

ancient-woodland resource, may go some way to explain the rarity of the species in

the county.


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11.1.3 In contrast, whiskered bats frequent hedgerows within an agricultural context, and as

the species also forages over open water, such as that abundantly represented by the

River Severn, its presence within the site was entirely predictable. On balance, and

accepting the lack of conclusive evidence, it is probable that the species present is

whiskered bat, and the following analysis proceeds on that basis.

11.1.4 Tables 17 through 21 on the following pages summarise the number of contacts

recorded for each species at each of the five detector locations during July, August

and September 2014; stratified according to rarity as defined by Wray et al. (2010).

Table 17. Total number of contacts for each bat species recorded in Location 1

at Ryall North during July, August and September 2014; stratified according to

rarity categories as defined by Wray et al. (2010).

IMPROVED CATTLE-GRAZED PASTURE

(Detector Location 1)

RARITY SPECIES TOTAL NUMBER OF CONTACTS

TOTAL JULY AUGUST SEPTEMBER

Rarer

Serotine 3 --- --- 3

Whiskered bat 24 2 5 31

Daubenton’s bat --- 1 3 4

Natterer’s bat 7 1 2 10

Leisler’s bat 1 --- --- 1

Noctule 11 --- --- 11

Leisler’s bat/noctule --- 1 --- 1

Lesser horseshoe

bat* --- --- 1 1

Common

Brown long-eared bat 11 --- 3 14

Soprano pipistrelle 40 26 498 564

Common pipistrelle 191 687 1545 2423

TOTAL 288 718 2057 3063




HEDGEROW




Rarer

Serotine --- 2 --- 2

Whiskered bat 2 14 10 26

Daubenton’s bat 78 2 6 86

Natterer’s bat 1 1 --- 2

Noctule 1 7 1 9

Common

Brown long-eared bat 2 6 7 15



TOTAL 289 507 2315 3111


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HEDGEROW




Rarer


Whiskered bat --- 40 3 43


Natterer’s bat 9 1 --- 10

Leisler’s bat --- 3 --- 3

Noctule 2 2 51 55

Leisler’s bat/noctule --- 1 --- 1

Common

Brown long-eared bat --- 16 --- 16



TOTAL 800 1911 3755 6466




HEDGEROW




Rarer




Natterer’s bat 1 1 1 3

Noctule 1 --- --- 1

Common

Brown long-eared bat --- --- 2 2



TOTAL 330 683 1958 2971




PARKLAND / SCATTERED TREES




Rarer Serotine --- 2 --- 2



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PARKLAND / SCATTERED TREES


RARITY SPECIES TOTAL NUMBER OF CONTACTS TOTAL

Rarer

Daubenton’s bat --- 1 3 4

Noctule 2 1 4 7

Leisler’s bat/noctule --- --- 1 1

Common Soprano pipistrelle 16 215 36 267


TOTAL 30 250 59 339

11.2 Survey efficacy: coverage

11.2.1 The survey performed at Ryall North exceeded the guidance set out by Hundt (2012)

by a 25% increase in meaningful survey coverage. Whilst it is accepted that

additional deployment of passive ultrasound monitors would have resulted in even

greater resolution, the only real merit of this would have been in the monitoring of

the hedge to be severed in the south-west corner of the site and two factors reduced

the need for this to a negligible level; firstly, this hedge will be the last to be severed

by the development, and will therefore only represent a temporary inconvenience;

secondly, the hedge had been flailed to c 1 m height during the survey and it was

concluded that its inclusion would be unlikely to add to the analysis but might well

lead to a negative bias in the data.

11.3 Survey efficacy: effort

Overall site bat fauna

11.3.1 Using a species accumulation analysis to assess the overall number of species

recorded throughout the entire sampling period (i.e. 12 nights) at all detector

locations, the results show that eight of the total 11 species were recorded after the

first night of deployment. Thereafter, an additional species was recorded on the

second; brown long-eared bat, fourth; Leisler’s bat (four contacts), and ninth; lesser

horseshoe bat (one contact) nights of deployment. The low number of contacts for

Leisler’s bat and lesser horseshoe bat does not indicate either species is a regular

visitor to the site. Indeed, in the case of Leisler’s bat, which has a loud call, the

opposite is inferred. Therefore, those species that were likely to visit the site with

any frequency had all been recorded by the fourth night of sampling and there was

no significant secondary peak or drop suggesting the immigration or emigration of

any aggregation of species as the year progressed. It is therefore concluded the

survey was entirely adequate to provide a species inventory of the site as a whole.

Figure 11 on the following page illustrates the number of new species recorded

during the survey throughout the entire sampling period for all detector locations.


RYALL NORTH

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- 77 - © AEcol 2015

Figure 11. The number of new bat species recorded during the ultrasound

activity survey throughout the entire sampling period July through September

2014 for all detector locations. Note: Two deployments were performed in

August for separate detectors.

Sample location faunas

11.3.2 Looking at the results in higher resolution, when assessing the number of species

recorded throughout the entire sampling period for each detector location, the results

show that for Locations 1, 4 and 5, the majority of species were also recorded on the

first night of deployment. However, the number of new species recorded at

Locations 1 and 5 appeared to remain constant throughout the sampling period, but

plateaued for Location 4 during August and most of September. At Location 2, all

species were recorded by the fifth night of deployment, whilst at Location 3, four

species were not recorded until the sixth night of deployment, but all were recorded

by the seventh night. Figures 12 and 13 on the following page illustrate the number

of new species recorded during the survey throughout the entire sampling period for

Locations 1, 4 and 5, and Locations 2 and 3 respectively.

Species accumulation summary

11.3.3 In summary, the overall site inventory was achieved, but by comparing the

individual accumulation curves in each habitat and location, it is clear that the

different habitats are visited at different points in the year by different species.

However, the pattern is more or less constant with no suggestion that any one habitat

becomes significantly more profitable in any single season.

0

1

2

3

4

5

6

7

8

1 n

igh

t

2 n

igh

ts

3 n

igh

ts

4 n

igh

ts

5 n

igh

ts

6 n

igh

ts

7 n

igh

ts

8 n

igh

ts

5 n

igh

ts

6 n

igh

ts

7 n

igh

ts

8 n

igh

ts

9 n

igh

ts

10 n

ights

11 n

ights

12 n

ights

03-

Jul

04-

Jul

05-

Jul

06-

Jul

11-

Aug

12-

Aug

13-

Aug

14-

Aug

26-

Aug

27-

Aug

28-

Aug

29-

Aug

15-

Sep

16-

Sep

17-

Sep

18-

Sep

Nu

mb

er o

f n

ew s

pec

ies

reco

rded

Date and number of nights deployment


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2014 for detector Locations 1, 4 and 5.



2014 for detector Locations 2 and 3.

11.4 Structure-based approach accuracy

11.4.1 The predictions resulting from the application of the structure-based approach,

truthing and the results of the surveys are set out in Table 22 on the following page.

0

1

2

3

4

5

6

1 night 2

nights

3

nights

4

nights

5

nights

6

nights

7

nights

8

nights

9

nights

10

nights

11

nights

12

nights

03-Jul 04-Jul 05-Jul 06-Jul 11-Aug12-Aug13-Aug14-Aug 15-Sep 16-Sep 17-Sep 18-Sep

Nu

mb

er o

f n

ew s

pec

ies

reco

rded


Location 1 Location 4 Location 5

0

1

2

3

4

5

6

1 night 2

nights

3

nights

4

nights

5

nights

6

nights

7

nights

8

nights

9

nights

10

nights

11

nights

12

nights

03-Jul 04-Jul 05-Jul 06-Jul 26-Aug27-Aug28-Aug29-Aug 15-Sep 16-Sep 17-Sep 18-Sep

Nu

mb

er o

f n

ew s

pec

ies

reco

rded


Location 2 Location 3


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Table 22. The cumulative results of the structure-based approach, truthing and

surveys at Ryall North.

METHOD

Ba

rba

stelle

Sero

tine

Bech

stein’s b

at

Bra

nd

t’s ba

t

Da

ub

ento

n’s b

at

Wh

iskered

bat

Na

tterer’s bat

Leisler’s b

at

No

ctule

Na

thu

sius’ p

ipistrelle

Co

mm

on

pip

istrelle

So

pra

no

pip

istrelle

Bro

wn

lon

g-ea

red b

at

Lesse

r ho

rsesho

e ba

t

Structural-

approach

predication:

Roosts

--- --- ---

Truthing --- --- --- --- --- --- ---

Roost

survey --- --- --- --- --- --- --- --- --- --- --- ---

Structural-

approach

predication:

Commuting

--- --- ---

Truthing --- --- --- Commuting-

route survey --- --- --- --- --- --- ---

Structural-

approach

predication:

Foraging

--- --- --- --- ---

Truthing --- --- --- --- ---

Foraging

survey

---

* * The individual lesser horseshoe contact did not suggest foraging.

11.4.2 Overall, the predictions of the structure-based roost assessment and truthing were

born out by the roost, commuting and foraging surveys in that no local population of

any bat species that was not predicted to occur, did in fact occur. Where variation

occurs, it is important to differentiate between positive correlation and minor

anomaly, such as the individual lesser horseshoe bat contact. The structural-

approach demonstrates positive associations defined by scientific experiment. This

is not to suggest that low quality areas of suitable habitat and even atypical habitats

will not be visited, but that that they will not be important to any local population.

Such an occurrence is more typical of a source/sink dynamic18

than the beginning of

18

Source/sink dynamics is a theoretical model used by ecologists to describe how variation in habitat quality

may affect population growth or decline. To illustrate, two areas of the same broad habitat type abut;

grassland. One is floristically rich cattle-grazed pasture, the other is a mono-species silage meadow. In

isolation the mono-species ley would be unable to support a population of any bat species, but if the pasture is

sufficiently profitable for a high recruitment rate in the local population of a particular bat species (this is the

source population), the weaker of these bats will ultimately be out-competed in the pasture and have to rely to


RYALL NORTH

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- 80 - © AEcol 2015

a longer term trend (i.e. an example of evolution in action). In particular, the

presence of an unexpected species foraging in an atypical habitat does not

immediately mean that habitat parcel is important to a local population and such

occurrences must be viewed in context.

11.5 Commuting/migration habitat assessment

Analysis constraints

11.5.1 Some species were recorded so infrequently that no meaningful analysis could be

conducted. Of the two species considered reliant upon linear landscape elements,

only the lesser horseshoe bat was recorded in the site, and this was by the detector

deployed in the centre of a cattle-grazed pasture. This does however confirm that the

SM2 detectors were sufficiently sensitive to detect the species, and it can therefore

be concluded that the data recorded is a true reflection of the species presence in (or

absence from) the site. The number of serotine and Natterer’s bat contacts were too

few to analyse on any meaningful scale. However, as both species is audible to SM2

detectors when commuting (Natterer’s bat is less frequently recorded whilst foraging

due to its gleaning strategy of listing for prey-generated noise), this in itself is

powerful as it demonstrates that none of the hedges sampled are important

commuting routes for any local population of these two species.

11.5.2 In order that a meaningful level of resolution was achieved, months where the total

number of contacts of an individual species was below 10 were excluded from the

analysis.

Whiskered bat

11.5.3 The seasonal and nightly patterns of whiskered/Brandt’s bat data recorded by

detectors in Locations 2, 3 and 4 (illustrated at Table 23 on the following page)

demonstrate that none of the hedges are important commuting routes for whiskered

bats in the July lactation period, suggesting that the linear landscape elements are

not important to bats suckling young. The contacts in August, whilst clearly

demonstrating the utility of the hedges, are not unusual numerically. The situation is

further clouded by the fact that whiskered bats forage on hedgerows and August is

the month when young become volant and venture forth from natal roosts. As a

result, there are more bats on the wing in August-October period than at any other

time of year. The decrease in the number of contacts in September suggests that the

hedges are not important migration routes between summer roosts and autumn

mating habitat.

11.5.4 In order to gauge habitat usage during the August peak, the 3rd

night of sampling

(28th

August 2014) In Location 3, which generated the highest number of calls was

isolated and the data divided into ‘passes’ that suggest a bat commuting, and

‘feeding buzzes’ that confirm successful foraging. Each of the different types of

some extent on the meadow (these are the sink population). This explains why some bats are occasionally

found foraging in atypical habitats and why this does not represent significance in terms of assessing impacts.


RYALL NORTH

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contact was then separated and plotted onto a temporal time-line, illustrated in

Figure 14.

Table 23. Total number of contacts for whiskered bat recorded in detector

Locations 2, 3 and 4 at Ryall North during July, August and September 2014.

Contacts for each month have been stratified to include only those more than

10 in total.

DETECTOR LOCATION

TOTAL NUMBER OF CONTACTS

TOTAL JULY (rearing period)

AUGUST (rearing period)

SEPTEMBER (mating period)

1 2 3 4 1 2 3 4 1 2 3 4

Location 2 -- -- -- -- 6 6 1 1 2 2 3 3 24

Location 3 -- -- -- -- -- 5 20 15 -- -- -- -- 40

Location 4 -- -- -- -- 16 10 9 3 2 4 2 3 49

TOTAL 0 0 0 0 22 21 30 19 4 6 5 6 147

Figure 14. Temporal time-line of whiskered bat passes and feeding-buzzes on

the night of 28th

August 2014 recorded in Location 3.

11.5.5 Reference to Figure 14 suggests the hedges are of greater value to commuting bats

than to foraging bats and that the small numbers of bats visiting the site are

travelling from some distance.

Daubenton’s bat

11.5.6 The seasonal and nightly patterns of Daubenton’s bat data recorded by detectors in

Locations 2, 3 and 4 (illustrated at Table 24 on the following page) demonstrate that

the hedges within the site are exploited by Daubenton’s bats in the July lactation

0

1

2

3

4

5

6

7

20:0

0

20:2

0

20:4

0

21:0

0

21:2

0

21:4

0

22:0

0

22:2

0

22:4

0

23:0

0

23:2

0

23:4

0

00:0

0

00:2

0

00:4

0

01:0

0

01:2

0

01:4

0

02:0

0

02:2

0

02:4

0

03:0

0

03:2

0

03:4

0

04:0

0

04:2

0

04:4

0

05:0

0

05:2

0

05:4

0

06:0

0

06:2

0

Nu

mb

er o

f co

nta

cts

Time

Feeding buzz Pass


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period, with Location 2 the most exploited, followed by Location 3 and Location 4 a

distant second. As the species does not exploit hedgerows for foraging it can be

assumed that all the contacts are bats commuting between a roost or roosts and the

abundance of aquatic foraging habitat on the River Severn. None of the hedges are

important commuting routes for Daubenton’s bats in the August weaning period,

and in September only Location 4 was used.

Table 24. Total number of contacts for Daubenton’s bat recorded in detector



10 in total.

DETECTOR LOCATION


TOTAL JULY

(rearing period) AUGUST

(rearing period) SEPTEMBER

(mating period)

1 2 3 4 1 2 3 4 1 2 3 4

Location 2 26 6 16 30 -- -- -- -- -- -- -- -- 78

Location 3 15 6 13 11 -- -- -- -- -- -- -- -- 45

Location 4 1 -- 3 11 -- -- -- -- 1 2 7 8 33

TOTAL 42 12 32 52 0 0 0 0 1 2 7 8

11.5.7 In order to gauge habitat usage during the peak periods, the 4th

night of sampling in

the July period (6th

July 2014) in Location 2, and the 4th

night of sampling in the

September period (18th

September 2014), which generated the highest numbers of

calls were isolated and the data plotted onto a temporal time-line, illustrated in

Figures 15 below and 16 on the following page.

Figure 15. Temporal time-line of Daubenton’s bat data on the night of 6th

July

2014 recorded in Location 2.

0

1

2

3

4

5

6

Nu

mb

er o

f co

nta

cts

Time

Feeding buzz Pass


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11.5.8 Reference to Figure 15 confirms that the habitat is used for commuting. However,

the peaks in Activity are relatively low (a maximum five in any ten-minute period)

and spread over the central part of the night. This might suggest bats commuting

between the River Severn and an off-site roost, but the low number of contacts and

the principle peak being in one hour alone, do not support any hypothesis that these

are females suckling young; were a local colony exploiting this hedgerow as a

primary commuting-route the number of contacts would be likely to be greater, and

more evenly spread throughout the evening. Furthermore, the first contacts would be

earlier; sunset was at 21:20 hours, the species typically emerges 40-50 minutes

following sunset (Jones & Walsh 2001) and so would have been emerging between

22:00 and 22:10 hours, but the first contact was not until past 22:50 hours, a

minimum of 40 minutes after their typical emergence time. As lactating females of

all species can be predicted to take the shortest route between roosts and foraging

grounds, this is an uncharacteristically long interval.

Figure 16. Temporal time-line of Daubenton’s bat data on the night of 18th

September 2014 recorded in Location 4.

11.5.9 Reference to Figure 16 confirms the habitat is exploited for commuting and that it is

not a primary flight-line for the local population at this time.


11.5.10 The seasonal and nightly patterns of brown long-eared bat data recorded by

detectors in Locations 2, 3 and 4 are illustrated at Table 25 on the following page.

11.5.11 Analysis of brown long-eared contacts is typically confounded by the species

low-intensity echolocation call. However, the call is loudest when the bet is

commuting and nothing in the data collected supports any suggestion that the hedges

within the site are important to the local population of the species.

0

1

2

19:1

0

19:4

0

20:1

0

20:4

0

21:1

0

21:4

0

22:1

0

22:4

0

23:1

0

23:4

0

00:1

0

00:4

0

01:1

0

01:4

0

02:1

0

02:4

0

03:1

0

03:4

0

04:1

0

04:4

0

05:1

0

05:4

0

06:1

0

06:4

0

Nu

mb

er o

f co

nta

cts

Time

Feeding buzz Pass


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Table 25. Total number of contacts for brown long-eared bat recorded in

detector Locations 2, 3 and 4 at Ryall North during July, August and

September 2014. Contacts for each month have been stratified to include only

those more than 10 in total.

DETECTOR LOCATION


TOTAL JULY



(mating period)

1 2 3 4 1 2 3 4 1 2 3 4 Location 2 -- -- -- -- -- -- -- -- -- -- -- -- --

Location 3 -- -- -- -- -- 6 10 -- -- -- -- -- 16

Location 4 -- -- -- -- -- -- -- -- -- -- -- -- --

TOTAL 0 0 0 0 0 6 10 0 0 0 0 0 27

Soprano pipistrelle

11.5.12 The seasonal and nightly patterns of soprano pipistrelle data recorded by

detectors in Locations 2, 3 and 4 are illustrated at Table 26.

Table 26. Total number of contacts for soprano pipistrelle recorded in detector



10 in total.

DETECTOR LOCATION


TOTAL JULY



(mating period)

1 2 3 4 1 2 3 4 1 2 3 4

Location 2 39 19 8 9 18 71 10 46 21 225 168 275 909

Location 3 154 135 19 17 119 137 550 83 249 786 1026 679 3954

Location 4 11 44 4 8 47 48 135 35 7 511 150 383 1383

TOTAL 204 198 31 34 184 256 695 164 277 1522 1344 1339 6248

11.5.13 Looking at the data in rudimentary terms it is immediately that the number of

contacts increases on all the hedges as the months progress. As soprano pipistrelles

also forage on hedgerows, in order to assess the proportion of commuting behaviour

from foraging behaviour, one night from each period was chosen at random from

each period and the data from these nights were divided into passes and feeding

buzzes and plotted onto a temporal time-line, the results of which are set out at

Figures 17, 18 and 19 on the following pages.

11.5.14 Assessing the data, the overall number of contacts recorded in July are

relatively low, particularly in light of the near vicinity of the River Severn. Sunset

on this date was at 21:20 hours and the first contact is not registered for almost an

hour. As the species is known to typically emerge around sunset and sometime

before, but at the latest within 30 minutes past sunset, and is a fast flier despite its

small size, this suggests the bat(s) arriving at the site have come from some distance

away and this is supported by the last contact, which is c. 1.5 hours before sunrise.


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The relatively low number of contacts (particularly when assessed in the context of

the typically large size of maternity colonies of the species; up to 800 females (Dietz

et al. 2011)) does not support the hypothesis that a maternity colony exploits the

hedgerows within the site during the lactation period. Certainly, if the hedgerows are

used by a maternity colony during this period, the inference is that they have another

route to the river and, as the levels of activity do not rise on any other on-site hedge

as they drop on another, the inference is that this route does not enter the site.

Figure 17. Temporal time-line of soprano pipistrelle passes and feeding-buzzes

on the night of 4th

July 2014 recorded in Location 4.


on the night of 27th


0

1

2

3

4

5

6

7

Nu

mb

er o

f co

nta

cts

Time

Feeding buzz Pass

0

2

4

6

8

10

12

14

16

20:0

0

20:2

0

20:4

0

21:0

0

21:2

0

21:4

0

22:0

0

22:2

0

22:4

0

23:0

0

23:2

0

23:4

0

00:0

0

00:2

0

00:4

0

01:0

0

01:2

0

01:4

0

02:0

0

02:2

0

02:4

0

03:0

0

03:2

0

03:4

0

04:0

0

04:2

0

04:4

0

05:0

0

05:2

0

05:4

0

06:0

0

06:2

0

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Time

Feeding buzz Pass


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11.5.15 The August and September timelines demonstrate the presence of foraging

bats in the vicinity of the detectors and not large-scale and regular communication

along the hedgerows.

Common pipistrelle

11.5.16 The seasonal and nightly patterns of common pipistrelle data recorded by

detectors in Locations 2, 3 and 4 are illustrated at Table 27.

Table 27. Total number of contacts for common pipistrelle recorded in detector



10 in total.

DETECTOR LOCATION


TOTAL JULY



(mating period)

1 2 3 4 1 2 3 4 1 2 3 4

Location 2 57 17 29 27 102 39 64 125 19 442 592 549 2062

Location 3 108 203 15 93 54 328 286 289 6 289 302 362 2335

Location 4 85 123 8 30 71 8 54 241 12 174 426 263 1495

TOTAL 250 343 52 150 227 375 404 655 37 905 1320 1174 5892

11.5.17 Looking at the data in rudimentary terms it is immediately evident that the

number of contacts increases on all the hedges as the months progress. As common

pipistrelles also forage on hedgerows, in order to assess the proportion of

commuting behaviour from foraging behaviour, one night from each period was

0

5

10

15

20

25

19:1

0

19:4

0

20:1

0

20:4

0

21:1

0

21:4

0

22:1

0

22:4

0

23:1

0

23:4

0

00:1

0

00:4

0

01:1

0

01:4

0

02:1

0

02:4

0

03:1

0

03:4

0

04:1

0

04:4

0

05:1

0

05:4

0

06:1

0

06:4

0

Nu

mb

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Time

Feeding buzz Pass


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chosen at random from each period and the data from these nights were divided into

passes and feeding buzzes and plotted onto a temporal time-line, the results of which

are set out at Figures 20, 21 and 22 on the following pages.

Figure 20. Temporal time-line of common pipistrelle passes and feeding-buzzes

on the night of 6th

July 2014 recorded in Location 3.




0

2

4

6

8

10

12

14

16

18

20

Nu

mb

ero

f co

nta

cts

Time

Feeding buzz Pass

0

5

10

15

20

25

20:0

0

20:2

0

20:4

0

21:0

0

21:2

0

21:4

0

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0

22:2

0

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0

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0

00:4

0

01:0

0

01:2

0

01:4

0

02:0

0

02:2

0

02:4

0

03:0

0

03:2

0

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0

04:0

0

04:2

0

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0

05:0

0

05:2

0

05:4

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Time

Feeding buzz Pass


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11.5.18 Assessing the data illustrated in the time-lines, the inference is of bats

foraging on the hedgerows. Certainly the July sample demonstrates that despite the

lower temperature (see Table 16), the hedgerow is still exploited for foraging in the

early morning, with a significant spike in the number of contacts at that time. The

central hedge (Location 3) is clearly the most used hedgerow, but the July sample

does not support the suggestion that lactating females exploit it, and the August and

whilst the August and September samples increase the number of contacts, the sheer

abundance of the species and their habit of foraging in a high number of relatively

small areas, confounds interpretation.

11.6 Habitat assessment

Whiskered bat

11.6.1 Table 28 on the following page sets out recorded whiskered bats contacts in all five

locations. The maximum number of contacts within the cattle-grazed pasture is 14

and of these contacts four were feeding-buzzes. The maximum number of contacts

on a hedge was 20 in Location 3 and of these contacts three were feeding-buzzes.

The maximum number of contacts within the parkland/scattered trees was four; too

few to infer any suggestion that this habitat is important to the local colonies of

either species.

Noctule

11.6.2 Table 29 on the following page sets out recorded noctule contacts in all five

locations. The maximum number of contacts within the cattle-grazed grassland was

0

2

4

6

8

10

12

14

16

18

20

19:1

0

19:4

0

20:1

0

20:4

0

21:1

0

21:4

0

22:1

0

22:4

0

23:1

0

23:4

0

00:1

0

00:4

0

01:1

0

01:4

0

02:1

0

02:4

0

03:1

0

03:4

0

04:1

0

04:4

0

05:1

0

05:4

0

06:1

0

06:4

0

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mb

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Time

Feeding buzz Pass


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four; too few to infer any suggestion that this habitat is important to the local

colonies of either species. As noctules are not reliant upon linear landscape elements

in order to commute/migrate, the contacts recorded at Location 2 in September can

be concluded to be of a bat, or bats commuting over or foraging in the vicinity. In

order to test this hypothesis the 33 calls recorded on 16th

September 2014 were

separated into passes and foraging-buzzes and plotted onto a temporal time-line,

which is provided at Figure 23 on the following page.

Table 28. Total number of contacts for whiskered bat recorded in all detector

Locations at Ryall North during July, August and September 2014. Contacts

for each month have been stratified to include only those more than 10 in total.

DETECTOR LOCATION


TOTAL JULY (rearing period)

AUGUST (rearing period)

SEPTEMBER (mating period)

1 2 3 4 1 2 3 4 1 2 3 4

Pasture (Location 1)

14 1 6 3 -- -- -- -- -- -- -- -- 24

Hedge (Location 2)

-- -- -- -- 6 6 1 1 2 2 3 3 24

Hedge (Location 3)

-- -- -- -- -- 5 20 15 -- -- -- -- 40

Hedge (Location 4)

-- -- -- -- 16 10 9 3 2 4 2 3 49

Parkland (Location 5)

-- -- -- -- -- -- -- -- 1 4 3 2 10

TOTAL 14 1 6 3 22 21 30 19 5 10 8 8 147

Table 29. Total number of contacts for noctule recorded in each Location at

Ryall North during July, August and September 2014. Contacts for each month

have been stratified to include only those more than 10 in total.

DETECTOR LOCATION


TOTAL JULY



(mating period)

1 2 3 4 1 2 3 4 1 2 3 4


1 4 4 2 -- -- -- -- -- -- -- -- 11

Hedge (Location 2)

-- -- -- -- -- -- -- -- -- -- -- -- --

Hedge (Location 3)

-- -- -- -- -- -- -- -- -- 33 13 5 51

Hedge (Location 4)

-- -- -- -- -- -- -- -- -- -- -- -- --


-- -- -- -- -- -- -- -- -- -- -- -- --

TOTAL 1 4 4 2 -- -- -- -- -- 33 13 5 62


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Figure 23. Temporal time-line of noctule passes and feeding-buzzes on the night

of 16th


11.6.3 The timeline indicate the hypothesis that the noctule contacts represent an individual

bat foraging (rather unsuccessfully) in the near vicinity. The individual feeding buzz

in what was a relatively prolonged bout of foraging on only one occasion confirms

the site is not important to any local population of the species.


11.6.4 Brown long-eared bat contacts within the suitable foraging habitat comprising the

isolated tree at Location 1 and the parkland/scattered trees at Location 5 are set out

at Table 30. Whilst the data confirm the species is present, the low number of

contacts are not unusual and might be attributable to a single bat foraging in the

vicinity of the oak upon which the Location 1 detector was deployed. In order to test

this hypothesis the data were plotted onto a temporal timeline and the results are

provided at Figure 24 on the following page.

Table 30. Total number of contacts for brown long-eared bat recorded in each

Location at Ryall North during July, August and September 2014. Contacts for

each month have been stratified to include only those more than 10 in total.

DETECTOR LOCATION


TOTAL JULY



(mating period)

1 2 3 4 1 2 3 4 1 2 3 4


-- 11 -- -- -- -- -- -- -- -- -- -- 11


-- -- -- -- -- -- -- -- -- -- -- -- --

TOTAL 0 11 0 0 0 0 0 0 0 0 0 0 11

0

2

4

6

8

10

12

14

19:1

0

19:4

0

20:1

0

20:4

0

21:1

0

21:4

0

22:1

0

22:4

0

23:1

0

23:4

0

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0

01:1

0

01:4

0

02:1

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02:4

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03:1

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0

04:1

0

04:4

0

05:1

0

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06:1

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06:4

0

Nu

mb

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cts

Time

Feeding buzz Pass


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Figure 24. Temporal time-line of brown long-eared bat activity at Location 1 on

the night of 4th

July 2014.

11.6.5 The time-line strongly indicates the contacts of brown long-eared bats were of a bat

or bats foraging in the canopy of the tree in which the detector was deployed.

Soprano pipistrelle

11.6.6 Table 31 on the following page sets out recorded soprano pipistrelle contacts in all

five locations. The implication of the data is that all five locations are exploited by

local populations of the species. As no framework exists against which to analyse

ultrasound activity data in order to provide a probable value for individual habitats

to such a generalist species, further focus on any individual attribute of the data

gathered will not provide any greater resolution than this statement; soprano

pipistrelles are present and forage within all three habitats, in descending order of

preference; hedgerows, cattle-grazed grassland and parkland/scattered trees.

Common pipistrelle

11.6.7 Table 32 on the following page sets out recorded common pipistrelle contacts in all

five locations. The implication of the data is that all five locations are visited by

local populations of the species, but only the cattle-grazed grassland and hedgerows

are of demonstrable value as foraging habitat. As no framework exists against which

to analyse ultrasound activity data in order to provide a probable value for individual

habitats to such a generalist species, further focus on any individual attribute of the

data gathered will not provide any greater resolution other than to suggest that the

ratio of passes to feeding-buzzes in detailed samples, suggest the habitats are not of

high profitability.

0

1

2

3

4

5

Nu

mb

er o

f co

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cts

Time

Feeding buzz Pass


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Table 31. Total number of contacts for soprano pipistrelle recorded in each



DETECTOR LOCATION


TOTAL JULY



(mating period)

1 2 3 4 1 2 3 4 1 2 3 4


7 17 13 3 9 8 9 -- 129 103 180 86 564

Hedge (Location 2)

39 19 8 9 18 71 10 46 21 225 168 275 909

Hedge (Location 3)

154 135 19 17 119 137 550 83 249 786 >

k* 679 3954

Hedge (Location 4)

11 44 4 8 47 48 135 35 7 511 150 383 1383


8 7 -- 1 30 67 98 20 7 16 4 9 267

TOTAL 219 22 44 38 223 331 802 184 413 1.6

k

1.5

k 1.4k 7077

* > 1k: Over 1,000 – (1,026)

Table 32. Total number of contacts for common pipistrelle recorded in each



DETECTOR LOCATION


TOTAL JULY



(mating period)

1 2 3 4 1 2 3 4 1 2 3 4


74 13 16 88 163 249 235 40 269 638 398 240 2423

Hedge (Location 2)

57 17 29 27 102 39 64 125 19 442 592 549 2062

Hedge (Location 3)

108 203 15 93 54 328 286 289 6 289 302 362 2335

Hedge (Location 4)

85 123 8 30 71 8 54 241 12 174 426 263 1495


4 4 1 3 8 1 9 4 -- -- -- -- 34

TOTAL 328 360 69 241 398 625 648 699 306 1.5

k

1.7

k

1.4

k 8349

12. IMPACT ASSESSMENT: ROOSTING HABITAT

12.1 Tree TN10.2

12.1.1 Tree TN10.2 will be lost as a result of the development. Wray et al. (2010) define


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both Daubenton’s bat and noctule as ‘rarer’ species. Natural England’s Bat

mitigation guidelines state that for small numbers of rarer species (not a maternity

site), sufficient mitigation/compensation would comprise: “Provision of new roost

facilities where possible. Need not be exactly like-for-like, but should be suitable,

based on species’ requirements. Minimal timing constraints or monitoring

requirements” (Mitchell-Jones 2004). Both Daubenton’s bats and noctule are known

to occupy artificial bat-boxes for the same purposes they occupy natural features in

trees (Dietz et al. 2011, Korsten 2012). There are therefore no grounds to suggest

that derogation under licence would be refused by Natural England.

12.1.2 Whilst no April visit was performed, there are no grounds to suggest this omission

materially altered the findings; species present and maximum number of bats, nor

would it alter the level of compensation in relation to the loss of Tree TN10.2.

13. IMPACT ASSESSMENT: COMMUTING/MIGRATION & FORAGING

HABITAT

13.1 Development and restoration scheme

13.1.1 The development will result in the loss of two bat habitats comprising:-

1. 0.3 ha of A3.1 – Woodland and scrub / Parkland/scattered trees / Broadleaved,

exploited by seven bat species comprising:-

a. Serotine;

b. Whiskered bat;

c. Daubenton’s bat;

d. Noctule;

e. Leisler’s bat;

f. Common pipistrelle; and

g. Soprano pipistrelle.

2. 1,115 m of J2.1.1 – Miscellaneous / Boundaries / Intact hedge, exploited by

seven bat species comprising:-

a. Serotine;

b. Whiskered bat;

c. Daubenton’s bat;

d. Natterer’s bat;

e. Common pipistrelle;

f. Soprano pipistrelle; and

g. Brown long-eared bat.

13.1.2 The restoration will result in the creation of four bat habitats comprising:-

1. 10.3 ha of B2.1 – Grassland and marsh / Neutral grassland / Unimproved,

suitable for seven bat species comprising:-

a. Serotine;

b. Daubenton’s bat;

c. Whiskered bat;

d. Natterer’s bat;

e. Leisler’s bat;

f. Noctule; and


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g. Common pipistrelle.

2. 5.9 ha of B5 – Grassland and marsh / Marsh/marshy grassland, suitable for an

individual bat species comprising:-

a. Brandt’s bat.

3. 17.04 of G1.1 – Open water / Standing water / Eutrophic, suitable for six bat

species comprising:-

a. Daubenton’s bat;

b. Whiskered bat;

c. Leisler’s bat;

d. Noctule;

e. Common pipistrelle; and

f. Soprano pipistrelle.

4. 1,750 m of J2.3 – Miscellaneous / Boundaries / Hedge with trees, representing a

57% increase in the primary foraging habitat in the locality.

13.1.3 In overall surface area, the 0.3 ha of foraging habitat will be replaced with 33.24 ha

representing a 10,980% increase. The development can therefore be predicted to be

wholly positive for local bat populations.

13.1.4 As the development and restoration are phased, the loss and replacement of the

commuting/foraging resource offered by the hedges will be staggered resulting in an

effect that is likely to be minor in inconvenience terms, but ultimately resulting in a

57% increase in the local resource. Furthermore, the lake envisaged will have a

‘bottle-neck’ c. 37 m wide, which is significantly less than the c. 57 m width of the

River Severn where it borders the site. This bottle-neck is linked with the hedge

network by hedge sections and reed-bed.

13.2 Serotine

13.2.1 No known serotine roost maternity colony within range of the site. Nine serotine

contacts were recorded over 12 nights in three seasons. There are no grounds to

predict the development will have any more than a negligible negative impact upon

the local population of this species and therefore no grounds to suggest derogation

under licence would be required in relation to a disturbance effect upon the local

population of serotine for the development to be granted planning permission.

13.3 Whiskered bat

Local population

13.3.1 No known whiskered bat maternity colony exists within range of the site.

Commuting/migration severance impact

13.3.2 Whiskered bats are not absolutely reliant upon hedgerows as commuting routes. The

species does exploit the hedgerow within the site both for commuting and foraging,

but a random sample of nightly data does not support any hypothesis that any local


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breeding population exploits the hedgerows present. Any minor short-term negative

effect will be adequately off-set by the restoration.

Foraging impact

13.3.3 Whiskered bats were recorded successfully foraging in both the cattle-grazed pasture

and on hedgerows. However, contacts were low overall and on the nights of highest

activity the number of feeding buzzes represented on 28% of contacts in the pasture,

and 15% of contacts on the hedgerow. The data does not support any hypothesis that

the site is a core foraging area for any local breeding population of whiskered bats.

Any minor short-term negative effect will be off-set by the long-term 9,013%

increase in foraging habitat, not including the 57% increase in hedgerow length.

Conclusion

13.3.4 There are no grounds to suggest derogation under licence would be required in

relation to a disturbance effect upon the local population of whiskered bat for the

development to be granted planning permission.

13.4 Daubenton’s bat

Local population

13.4.1 No known Daubenton’s bat maternity colony exists within range of the site.


13.4.2 Daubenton’s bats are not absolutely reliant upon hedgerows as commuting routes.

Hedges within the site are exploited by commuting Daubenton’s bats, but a random

sample of nightly data does not support any hypothesis that any local breeding

population exploits them. The development will not result in a barrier to bats passing

from east to west as a network of linear landscape elements will remain available.

Any minor short-term negative effect will be adequately off-set by the restoration.

Foraging impact

13.4.3 There are no grounds to suggest the habitats present are important to any local

population of Daubenton’s bats for foraging. However, the restored site will provide

a 9,013% increase in foraging habitat in the locality, not including the 57% increase

in hedgerow length.

Conclusion


relation to a disturbance effect upon the local population of Daubenton’s bat for the



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13.5 Natterer’s bat

13.5.1 No known Natterer’s bat maternity colony exists within range of the site. 25

Natterer’s bat contacts were recorded over 12 nights in three seasons. There are no

grounds to predict the development will have any more than a negligible impact

upon the local population of this species. There are no grounds to suggest derogation

under licence would be required in relation to a disturbance effect upon the local

population of Natterer’s bat for the development to be granted planning permission.

13.6 Leisler’s bat

13.6.1 No known Leisler’s bat maternity colony exists within range of the site. Four

Leisler’s bat contacts were recorded over 12 nights in three seasons. There are no

grounds to predict the development will have any more than a negligible impact

upon the local population of this species. There are no grounds to suggest derogation

under licence would be required in relation to a disturbance effect upon any local

population of Leisler’s bat for the development to be granted planning permission.

13.7 Noctule

Local population

13.7.1 No known noctule maternity colony exists within range of the site.


13.7.2 Not applicable.

Foraging impact

13.7.3 The site is of negligible value to the species.

Conclusion


relation to a disturbance effect upon the local population of noctule for the


13.8 Brown long-eared bat

Local population

13.8.1 No known brown long-eared bat maternity colony exists within range of the site


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13.8.2 Minor impact restricted to individual bats.

Foraging impact

13.8.3 Minor impact restricted to individual bats.

Conclusion


relation to a disturbance effect upon the local population of brown long-eared bat for

the development to be granted planning permission.

13.9 Soprano pipistrelle

Local population

13.9.1 No known soprano pipistrelle maternity colony exists within range of the site


13.9.2 Looking at the data in rudimentary terms, it is immediately evident that the number

of contacts increases on all the hedges as the months progress. This is interesting,

because were any local population dependent upon the hedges as a commuting route

between a nursery roost and a core foraging ground the opposite would be expected

due to the need for the females to return to the roost at regular intervals to suckle

young in July, and the colonies fragmenting in August before dividing into

individual mating groups of c. 2-6 bats in September. In fact the number of contacts

in July is relatively low in respect of the close proximity of the River Severn, and

the gradual increase in the number of contact through August and into September

may simply be a reflection of the wider distribution of bats at this time as nursery

colonies fragment, and the increased competition for resources resulting in a greater

diversity of habitats being exploited.

Foraging impact

13.9.3 Riparian habitats are the primary foraging grounds of soprano pipistrelle, arable is

the least profitable and agricultural grassland appears to be of no value to the species

at all (Davidson-Watts et al. 2006). As maternity colonies of soprano pipistrelle

have core foraging area under half that occupied by common pipistrelles (Davidson-

Watts et al. 2006), the increase in sheltered aquatic foraging habitat at Ryall North

can therefore be predicted to be of significant benefit to the local population.

Conclusion


relation to a disturbance effect upon the local population of soprano pipistrelle for


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the development to be granted planning permission.

13.10 Common pipistrelle

Local population

13.10.1 Two probable maternity colonies of common pipistrelle are known to occur

within range of the site.


13.10.2 The observation in relation to the increase in the number of common

pipistrelle contacts mirrors that of the soprano pipistrelle. In any case, as common

pipistrelles frequently cross open areas of over 100 m (Verboom & Huitema 1997)

and may cross over 375 m of open ground between sheltered linear landscape

elements (Simon et al. 2004), and the maximum distance across the site is c. 450 m.

at its widest point, even were no network of linear landscape elements available to

the species the site would be unlikely to represent an absolute barrier. The loss of the

communicating hedgerows will result in a negative effect, but there are no grounds

to suggest any maternity colony of the species is exploits hedgerows during the July

lactation period and a network of linear landscape elements will remain, surrounding

the site. As the removal of hedgerows will be phased, it is likely the effect will be

one of inconvenience rather than a threat to the species local status.

Foraging impact

13.10.3 The common pipistrelle is the UK’s most abundant bat species and also the

most cosmopolitan. It is therefore thought of as a true ‘generalist’ species. In fact

this is an overstatement and unsupported by scientific accounts. In their study in the

Avon Valley, Davidson-Watts et al. (2006) found the common pipistrelle had a clear

preference for deciduous woodland, followed by grassland, then riparian habitat,

suburban areas, mixed woodland, riparian woodland and, in distant last places;

arable and finally coniferous woodland. As the species is an ‘edge’ specialist that

preys on Diptera (true flies), its presence in grassland and arable habitat is restricted

to hedges, which provide wind-shelter to swarms of their prey. The fact that

suburban areas are significantly selected over arable, coupled with an inference that

the hedgerows within the site are not particularly profitable as foraging habitat,

demonstrates that the local status of the species is unlikely to be much affected by

the loss of the foraging habitats at Ryall North. This conclusion is strengthened by

the fact that the removal of hedgerows during the development, and the

reinstatement of hedgerows in restored areas will be phased rather than there being a

sudden and comprehensive loss.

Conclusion

13.10.4 There are no grounds to suggest derogation under licence would be required

in relation to a disturbance effect upon the local population of common pipistrelle

for the development to be granted planning permission.


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14. CONCLUSIONS

Efficacy

14.1.1 All aspects of the structure-based approach, truthing and subsequent survey for bat

roosts, commuting/migration routes and foraging habitat were evidence-supported

and performed to a high standard. Furthermore, the methods employed were both

proportionate to the level of risk, ensured all personnel involved adhered to the

CIEEM Code of Professional Conduct in all areas, and all aspects of the findings of

the High Court in the Morge judgment were satisfied.

Bat roosts

14.1.2 An individual sporadically occupied tree-roost occupied by low numbers of either

Daubenton’s bat or noctule was recorded. A detailed mitigation and compensation

strategy has been provided to the Mineral Planning Authority. Derogation under

licence will be required, but there are no grounds to suggest Natural England would

refuse this licence.

Commuting/migration habitat

14.1.3 Commuting routes exploited by seven bat species were recorded. None of the

species recorded are absolutely reliant upon linear landscape elements, and none of

the linear landscape elements present are the sole communication between any

known or unknown bat-roost and core foraging areas. There are no grounds to

suggest the development would result in a barrier effect on any local population of

any bat species sufficient to require derogation under licence. A detailed restoration

strategy has been provided to the Mineral Planning Authority. This will reinstate the

network of commuting routes for all species recorded.

Foraging habitat

14.1.4 Seven bat species were recorded during the foraging habitat survey. There are no

grounds to suggest the site represents more than 5% of the foraging habitat resource

available to bats occupying known roosts outside the site. There are no grounds to

suggest any of the habitats within the site are part of a core foraging area of any

local colony of any bat species occupying any unknown roost, during the most

sensitive July lactation period. The loss of foraging habitats will be phased, and

therefore temporary. Abundant foraging habitat will exist in the locality for all the

species identified during the survey. There are therefore no grounds to suggest the

development would result in a disturbance affect sufficient to warrant derogation

under licence due to the loss of foraging habitat in respect of any bat species.

Nevertheless, the detailed restoration strategy submitted to the Mineral Planning

Authority for approval will result in a 57% increase in hedgerow length, and a 33.24

ha (10,980%) increase of suitable foraging habitat for all species recorded during the

survey.


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15. REFERENCES

15.1 Section 2

Sub-section 2.3

JNCC 2010. Handbook for Phase 1 habitat survey: A technique for environmental

audit. Joint Nature Conservation Committee, Peterborough.

15.2 Section 3

Sub-section 3.2

Hayes J, Ober H & Sherwin R 2009. Survey and Monitoring of Bats. In: Kunz T &

Parsons S (Eds.) 2009. Ecological and Behavioural Methods for the Study of Bats:

Second Edition. The John Hopkins University Press, Baltimore.

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ecologically sustainable forest management. Conservation Biology 14: 941-950.

Scott C & Altringham J 2014. WC1015 Developing Effective Methods for the

Systemeatic Surveillance of Bats in Woodland Habitats in the UK. Final report to

DEFRA, University of Leeds.

Sub-section 3.6

EUROPEAN COMMISSION 2007. Guidance document on the strict protection of

animal species of community interest under the Habitats Directive 92/43/EEC.

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bats in Britain: geographical, land class and local habitat relationships. Journal of

Applied Ecology 33: 519-529.

Walsh A & Harris S 1996b. Foraging habitat preference of vespertilionid bats in

Britain. Journal of Applied Ecology 33: 508-518.

Sub-section 3.7

Kunz T & Parsons S (Eds.) 2009. Ecological and Behavioural Methods for the Study

of Bats: Second Edition. The John Hopkins University Press, Baltimore.

Lindenmayer D, Margules C & Botkin D 2000. Indicators of biodiversity for

ecologically sustainable forest management. Conservation Biology 14: 941-950.

Sub-section 3.9

BCT 2014. The state of the UK’s bats 2014: National Bat Monitoring Programme

Population Trends. Bat Conservation Trust, London.


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Worcestershire Biodiversity Partnership 2008. Worcestershire Biodiversity Action

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15.3 Section 4

Sub-section 4.1



Sub-section 4.2


BCT 2010. The National Bat Monitoring Programme: Annual Report 2009. Bat

Conservation Trust, London & Joint Nature Conservancy Council, Peterborough.

Dietz C, Helversen O & Dietmar N 2011. Bats of Britain, Europe & Northwest

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Stebbings R, Yalden D & Herman J 2007. Which Bat Is It? The Mammal Society.

Sub-section 4.3


Andrews H et al. 2013. Bat Tree Habitat Key. AEcol, Bridgwater

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Mitchell-Jones A 2004. Bat Mitigation Guidelines. English Nature, Peterborough.


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Stebbings R, Mansfield H & Fasham M 2005. Bats, In: Hill D, Fasham M, Tucker

G, Shewry M & Shaw P (eds) 2005. Handbook of Biodiversity Methods. Cambridge

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15.4 Section 5

Sub-section 5.1



Sub-section 5.2


Berthinussen A & Altringham J 2012. Do Bat Gantries and Underpasses Help Bats

Cross Roads Safely? PLoS one, www.plosone.org.





Hutterer R, Ivanova T, Meyer-Cords C & Rodrigues L 2005. Bat Migrations in

Europe – A Review of Banding Data and Literature. Naturschutz und Biologische

Vielfalt Heft 28, Federal Agency for Nature Conservation, Bonn 2005.

Kerth G & Melber M 2009. Species-specific barrier effects of a motorway on the

habitat use of two threatened forest-living bat species. Biological Conservation 142:

270-279.

Simon M, Hüttenbügel S & Smit-Viergutz J 2004. Ecology and Conservation of

Bats in Villages and Towns. Bunesamt für Naturschutz, Bonn.

Verboom B & Huitema H 1997. The importance of linear landscape elements for the

pipistrelle Pipistrellus pipistrellus and the serotine bat Eptesicus serotinus.

Landscape Ecology 12(2): pp 117-125.

Sub-section 5.3



Sub-section 5.4




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15.5 Section 6

Sub-section 6.1



Sub-section 6.2



Entwistle A, Harris S, Hutson A, Racey P, Walsh A, Gibson S, Hepburn I &

Johnson J 2001. Habitat Management for Bats – A guide for land managers, land

owners and their advisors. Joint Nature Conservation Committee, Peterborough.



Soanes C, Hawker S & Elliot J (eds.) 2005. Oxford English Dictionary. Oxford

University Press, Oxford.

Sub-section 6.3



Sub-section 6.4



15.6 Section 7

Sub-section 7.2


15.7 Section 8

Sub-section 8.5

Hundt L 2012. Bat Surveys: Good Practice Guidelines – 2nd

Edition. Bat

Conservation Trust, London.

Natural England undated. Standing Advice Species Sheet: Bats. Natural England,

Peterborough.


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Sub-section 8.6


BCT 2007b. BCT Mitigation Conference Proceedings: University of Leicester 25-26

April 2007. Bat Conservation Trust.

Hoying K & Kunz T 1998. Variation in the size at birth and post-natal growth the

insectivorous bat Pipistrellus subflavus (Chiroptera: Vespertilionidae). Journal of

Zoology (London) 245: 15-17.


Edition. Bat


Kunz T, Betke M, Hristov N & Vonhof M 2009. Methods of Assessing Colony Size,

Population Size, and Relative Abundance of Bats. In: Kunz T & Parsons S (eds.)

2009. Ecological & Behavioural Methods for the Study of Bats. The Johns Hopkins

University Press, Baltimore.

Kunz T & Anthony E 1996. Variation in the time of nightly emergence behaviour in

the little brown bat Myotis lucifugus (Chiroptera: Vespertilionidae). Pp. 225-235, In:

Contributions in Mammalogy: A Memorial Volume Honoring Dr. J. Knox Jones, Jr.

(H. H. Genoways and R.J. Baker, Eds.) Museum of Texas Tech University,

Lubbock, Texas.

Sub-section 8.7

Dense C & Rahmel U 2002. Untersuchungen zur Habitatnutzung der GroBen

Bartfledermaus (Myotis brandtdii) im nordwestlichen Niedersachsen. In:

MESCHEDE, A., HELLER, K.-G. & BOYE, P. eds. Okolgie, Wanderungen und

Genetik von Fledermausen in Waldern – Untersuchungen als Grundlage fur den

Fledermausschutz, 51-68. Munster: Landsirtschaftsverlag.. Cited in: Boye P & Dietz

M 2005. Development of good practice guidelines for woodland managements for

bats. English Nature Research Reports 661, Peterborough.

Dietz M 1993. Beobachtungen zur Lebensraumnutzung der Wasserfledermaus

(Myotis daubentonii Kuhl 1891) in einem urbanen Untersuchungsgebiet in

Mittelhessen. Justus-Liebig-University of GieBen: Diploma thesis. Cited in: Boye P

& Dietz M 2005. Development of good practice guidelines for woodland

managements for bats. English Nature Research Reports 661, Peterborough.

Dietz M & Pir J 2011. Distribution, Ecology and Habitat Selection by Bechstein’s

Bat (Myotis bechsteinii) in Luxembourg. Ökologie der Säugetiere 6, Laurenti,

Verlag.



Frank R 1994. Baumhohlenuntersuchung im Philosophenwald in GieBen.


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Kartierung der Baumhohlen und ihre Nutzung im Jahresverlauf durch Vogel und

Saugetiere unter besonderer Berucksichtigung der Fledermause und ausgewhlter

Verhaltensweisen. Arbeitskreis Wildbiologie an der Justus – Liebig – Universitat in

GieBen e.V: Master thesis. Cited in: Boye P & Dietz M 2005. Development of good

practice guidelines for woodland managements for bats. English Nature Research

Reports 661, Peterborough.

Kerth G 1998. Sozialverhalten und genetische Populationsstruktur bei der

Bechsteinfledermaus Myotis bechseini. Berelin: Wissenschaft und Technik Verlag.

Cited in: Boye P & Dietz M 2005. Development of good practice guidelines for

woodland managements for bats. English Nature Research Reports 661,

Peterborough.

Schorcht W., et al 2002. Zur Ressourcennutzung von Rauhhautfledermausen

(Pipistrellus nathusii) in Mecklenburg. In: MESCHEDE, A., HELLER, K.-G. &

BOYE, P. eds. Okolgie, Wanderungen und Genetik von Fledermausen in Waldern,

191-212. Untersuchengen als Grundlage fur den Fledermausschutz Munster:

Landwirtschaftsverlag. Schriftenreihe fur Landschaftspflege und Naturschutz 71, p.


woodland managements for bats. English Nature Research Reports 661,

Peterborough.

Sub-sections 8.8 and 8.10

Andrews H & Gardener M 2015. Surveying Trees for Bat Roosts: Encounter

Probability v. Survey Effort. CIEEM In Practice 88: 33-37.

15.8 Section 9

Sub-section 9.2



15.9 Section 10

Sub-section 10.5

MacSwiney M, Clarke F & Racey P 2008. What you see is what you get: the role of

ultrasonic detectors in increasing inventory completeness in Neotropical bat

assemblages. Journal of Applied Ecology 45: 1364-1371.

O’Farrell M & Gannon W 1999. A Comparison of Acoustic Versus Capture

Techniques for the Inventory of Bats. Journal of Mammalogy 80(1) 24-30.


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Sub-section 10.6

Altringham J 2012. Improving the evidence in evidence-based conservation. CIEEM

In Practice 78: 28-32.


Edition. Bat


Natural England undated. Standing Advice Species Sheet: Bats. Natural England,

Peterborough.

Sub-section 10.7

Adams A 2013. Assessing and Analyzing Bat Activity with Acoustic Monitoring:

Challenges and Interpretations. PhD thesis, The School of Graduate and

Postdoctoral Studies, The University of Western Ontario, London, Ontario, Canada.

Altringham J 2003. British Bats. Collins New Naturalist series No 93, Harper

Collins, London.

Andrews H 2010. Nightly activity patterns of bats in an area of ancient semi-natural

woodland at Asham Wood SSSI, Nr Frome, Somerset; Implications for the timing of

bat activity surveys. Dissertation submitted to The University of Birmingham for the

degree of Master of Science in Biological Recording.

Bontadina F, Schofield H & Naef-Daenzer B 2002. Radio-tracking reveals that

lesser horseshoe bats (Rhinolophus hipposideros) forage in woodland. J. Zool.

London, 258: 281-290.

Broders H 2003. Another quantitative measure of bat species activity and sampling

intensity considerations for the design of ultrasonic monitoring studies. Acta

Chiropterologica 5: 235–241.

Froidevaux J, Zellweger F, Bollman K & Obrist M 2014. Optimizing passive


Hayes J 1997. Temporal variation in activity of bats and the design of echolocation

monitoring studies. Journal of Mammalogy 78:514–524.


Edition. Bat


Jones K & Walsh A 2001. A guide to British bats. Field Studies Council/The

Mammal Society.

Mackie I & Racey P 2007. Habitat use varies with reproductive state in noctule bats

(Nyctalus noctula): Implications for conservation. Biological Conservation 140: 70-

77.


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Murphy S, Greenaway F & Hill D 2012. Patterns of habitat use by female brown

long-eared bats presage negative impacts of woodland conservation management.

Journal of Zoology 288: 177-183.

Scott C & Altringham J 2014. WC1015 Developing effective methods for the

systematic surveillance of bats in woodland habitats in the UK: Final Report August

2014. School of Biology, University of Leeds, Leeds.



Skalak S, Sherwin R & Brigham M 2012. Sampling period, size and duration


Ecology and Evolution 3: 490-502.

Stahlschmidt P & Brühl C 2012. Bats as bioindicators – the need of a standardized

method for acoustic bat activity surveys. Methods in Ecology and Evolution 3: 503-

508.

Staton T & & Poulton S 2012. Seasonal variation in bat activity in relation to

detector height: a case study. Acta Chiropterologica 14(2): 401-408.

Swift S & Racey P 2002. Gleaning as a foraging strategy in Natterer’s bat Myotis

nattereri. Behav Ecol Sociobiol 52: 408-416.

Sub-section 10.8

Ahlen I & Baagoe H 1999. Use of ultrasound detectors for bat studies in Europe:

experiences from field identification, surveys, and monitoring. Acta

Chiropterologica 2: 137-150.

Barclay R 1999. Bats are not birds – a cautionary note on using echolocation calls to

identify bats: a comment. Journal of Mammalogy 80: 290-296.

Briggs B & King D 1998. The Bat Detective: A Field Guide for Bat Detection.

BatBox Ltd, Steyning, West Sussex.

Corben C & Fellers G 2001. Short Notes: Choosing the ‘correct’ bat detector – a

reply. Acta Chiropterologica 3(2): 245-256.

Fenton M & Bell G 1981. Recognition of Insectivorous Bats by their Echolocation

Calls. Journal of Mammalogy 62: 233-243.

Fenton M 2000. Choosing the ‘correct’ bat detector. Acta Chiropterologica. 2: 215-

224.

Fenton M, Bouchard S, Vonhof M & Zigouris J 2001. Time-expansion and zero-

crossing period meter systems present significantly different views of echolocation

calls of bats. Journal of Mammalogy 82: 721-727.


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Fenton M 2003. Science and the conservation of bats: where to next? Wildlife

Society Bulletin 31: 6-15.

Findley J 1993. Bats – a community perspective. Cambridge University Press,

Cambridge.

Hayes J, Ober H & Sherwin R 2009. Survey & Monitoring In: Kunz T & Parsons S

(eds.) 2009. Ecological & Behavioural Methods for the Study of Bats. The Johns

Hopkins University Press, Baltimore.

Jennings N, Parsons S & Pocock M 2008. Human vs. machine: identification of bat

species from their echolocation calls by humans and by artificial neural networks.

Canadian Journal of Zoology 86: 371-377.

Kalcounis M, Hobson K, Bigham R & Heckler K 1999. Bat activity in the boreal

forest: importance of stand type and vertical strata. Journal of Mammalogy 80: 673-

682.

Kapteyn K (ed.) 1993. Proceedings of the first European bat detector workshop.

Netherlands Bat foundation, Amsterdam.

Kunz T, Betke M, Hristov N & Vonhof M 2009. Methods of Assessing Colony Size,

Population Size, and Relative Abundance of Bats. In: Kunz T & Parsons S (eds.)

2009. Ecological & Behavioural Methods for the Study of Bats. The Johns Hopkins

University Press, Baltimore.

O’Farrell M, Miller B & Gannon W 1999. Qualitative identification of free-flying

bats using the AnaBat detector. Journal of Mammalogy 80: 11-23.

O’Farrell M & Gannon W 1999. A comparison of acoustic versus capture

techniques for the inventory of bats. Journal of Mammalogy 80: 297-302.

Vaughn N, Jones G & Harris S 1997a. Identification of British bat species by

multivariate analysis of echolocation call parameters. Bioacoustics 7: 189-207.

Walsh A & Catto C 2004. Survey and Monitoring. In: Mitchell-Jones AJ & McLeish

AP (Eds.) 2004. The Bat Workers Manual. Joint Nature Conservation Committee,

Peterborough.

Sub-section 10.9

Adams A 2013. Assessing and Analyzing Bat Activity with Acoustic Monitoring:

Challenges and Interpretations. PhD thesis, The School of Graduate and

Postdoctoral Studies, The University of Western Ontario, London, Ontario, Canada.

Froidevaux J, Zellweger F, Bollman K & Obrist M 2014. Optimizing passive



Edition. Bat


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Kunz T & Parsons S (Eds.) 2009. Ecological and Behavioural Methods for the Study

of Bats: Second Edition. The John Hopkins University Press, Baltimore.

Russ J 2012. British Bat Calls: A Guide to Species Identification. Pelagic

Publishing, Exeter.

Scott C & Altringham J 2014. WC1015 Developing effective methods for the

systematic surveillance of bats in woodland habitats in the UK: Final Report August

2014. School of Biology, University of Leeds, Leeds.

Skalak S, Sherwin R & Brigham M 2012. Sampling period, size and duration


Ecology and Evolution 3: 490-502.

Stahlschmidt P & Brühl C 2012. Bats as bioindicators – the need of a standardized

method for acoustic bat activity surveys. Methods in Ecology and Evolution 3: 503-

508.

15.10 Section 11

Sub-section 11.1

Boye P & Dietz M 2005. Development of good practice guidelines for Woodland

Management for Bats. English Nature research reports No. 661, Natural England

Peterborough.

Spizenberger F 2001. Die Säugetierfauna Österreichs. Grüne Reihe 13, Vienna:

Bundesministerium für Land und Forstwirtschaft, Umwelt und Wasserwirtschaft.


Woodland Management for Bats. English Nature research reports No. 661, Natural

England Peterborough.

Taake K 1984. Strukturelle Untersciede zwichen den Sommerhabitaten von Kliener

und Großer Bartfledermaus (Myotis mystacinus und M. brandti) in Westfalen.

Nyctalus 2:16=32. Cited in: Harris S & Yalden D (eds.) 2008. Mammals of the

British Isles: Handbook, 4th Edition. The Mammal Society, London.



Sub-section 11.2


Edition. Bat



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Sub-section 11.5



Jones K & Walsh A 2001. A Guide to British Bats. Field Studies Council/The

Mammal Society, Southampton.

15.11 Section 12

Sub-section 12.1



Korsten E 2012. Vleermuiskasten: Overzicht van toepassing, gebruik en

succesfactoren. Zoogdier Vereniging, Bureau Waardenburg bv.

Mitchell-Jones A 2004. Bat Mitigation Guidelines. English Nature, Peterborough.



15.12 Section 13

Sub-section 13.9

Davidson-Watts I, Walls S & Jones G 2006. Different habitat selection by

Pipistrellus pipistrellus and Pipistrellus pygmaeus identifies distinct conservation

needs for cryptic species of echolocating bats. Biological Conservation 133: 118-

127.

Sub-section 13.10

Davidson-Watts I, Walls S & Jones G 2006. Different habitat selection by

Pipistrellus pipistrellus and Pipistrellus pygmaeus identifies distinct conservation

needs for cryptic species of echolocating bats. Biological Conservation 133: 118-

127.



Verboom B & Huitema H 1997. The importance of linear landscape elements for the

pipistrelle Pipistrellus pipistrellus and the serotine bat Eptesicus serotinus.

Landscape Ecology 12(2): pp 117-125.

___________________________


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APPENDIX A. A REVIEW OF THE COMMUTING RANGES OF BRITISH BATS

USED TO DEFINE AN APPROPRIATE RADIUS FOR SEARCHES OF HISTORIC

DATA-SETS.

INTRODUCTION

In order to define an appropriate buffer for data-requests a literature review of all references

to the commuting ranges of individual bat species was performed (see Table A1). A single

average and maximum commuting range was calculated, these are set out in Table A2.

Table A1. Results of a review of commuting distances of bats native to the UK.

BAT SPECIES AVERAGE COMMUTING DISTANCE MAXIMUM COMMUTING DISTANCE

Barbastelle

Barbastella barbastellus 4.5 km (Dietz et al. 2011)

18 km (Schofield & Mitchell-Jones 2003)

18 km (Harris & Yalden 2008)

Serotine

Eptesicus serotinus

6.5 km (Catto et al. 1996) 8.2 km (Robinson & Stebbings 1997)


6.5 km (Harris & Yalden 2008) 4.5 km (Dietz et al. 2011)

6 km (Schofield & Mitchell-Jones 2003) 12 km (Dietz et al. 2011)

Bechstein’s bat

Myotis bechsteinii

0.7 km (Fitzsimons et al. 2002)

0.3 - 1 km (Altringham 2003)

1 km (Harris & Yalden 2008) 1 km (Dietz et al. 2011)

1.4 km (Fitzsimons et al. 2002)

2.5 km (Dietz et al. 2011)

Brandt’s bat

Myotis brandtii 2.3 km (Harris & Yalden 2008)

10 km (Dense & Rahmel 2002)

10 km (Dietz et al. 2011)

Daubenton’s bat

Myotis daubentonii

2 km (Swift & Racey 1983) 10 km (Richardson 1985)

2.3 km in females, 3.7 km in males (Encarnacao et

al. 2005) 3 km (Altringham 2003)


3.7 km, max 6-10 km (Dietz et al. 2011)

10 km (Harris & Yalden 2008)

Whiskered bat

Myotis mystacinus NO DATA

2.8 km (Cordes 2004) 2.2 km (Harris & Yalden 2008)


Natterer’s bat

Myotis nattereri NO DATA

4 km (Smith & Racey 2005)


Leisler’s bat

Nyctalus leisleri

4.2 km (Waters et al. 1999)

4.2 km (Harris & Yalden 2008)


5.75 km (Waters et al. 1999)



Noctule

Nyctalus noctula

6 km (Schober & Grimmberger 1997) 6 km (Mackie & Racey 2007)



10 km (Richardson 2000)



Pipistrellus nathusii 6.5 km (Dietz et al. 2011) ?

Common pipistrelle


1 - 2 km (Schober & Grimmberger 1997, Davidson-

Watts et al. 2006) 3-4 km (Schofield & Mitchell-Jones 2003)



5 km (Altringham 2003) 5.1 km (Harris & Yalden 2008)

Soprano pipistrelle


1.7 km (Harris & Yalden 2008).

1.5 km (Dietz et al. 2011). ?


Plecotus auritus

0.5 km (Entwistle et al. 1996, Richardson 2000)

500 m (Dietz et al. 2011)

3 km (Entwistle et al. 1996, Richardson 2000)


Grey long-eared bat

Plecotus austriacus

1.1 - 3.3 km (Swift and Racey 1983, Fuhrmann &

Seitz 1992, Fluckiger & Beck 1995) Maximum 5.5 km (Dietz et al. 2011)

Greater horseshoe bat

Rhinolophus

ferrumequinum

2.1 km (Duverge & Jones 1994, Jones et al. 1995)

6.2 km (Richardson 2000)

3-4 km (Harris & Yalden 2008) 2.1 km (Dietz et al. 2011)

2.1 km (Duverge & Jones 1994, Jones et al.

1995)

14 km (Harris & Yalden 2008) 5 km (Dietz et al. 2011)


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BAT SPECIES AVERAGE COMMUTING DISTANCE MAXIMUM COMMUTING DISTANCE


Rhinolophus

hipposideros

0.6 km (Bontadina et al. 2002)

2 km (Vaughn et al. 1997, Schofield & Mitchell-

Jones 2003) 2.5 km (Harris & Yalden 2008)


4.2 km (Bontadina et al. 2002)

4 km (Harris& Yalden 2008) 5 km (Dietz et al. 2011)

Table A2. Mean average commuting range of bats native to the UK.

BAT SPECIES AVERAGE RANGE MAXIMUM RANGE

Barbastelle

Barbastella barbastellus 4.5 km 18 km

Serotine

Eptesicus serotinus 5.5 km 9 km

Bechstein’s bat

Myotis bechsteinii 0.8 km 1.95 km

Brandt’s bat

Myotis brandtii 2.3 km 10 km

Daubenton’s bat

Myotis daubentonii 4.4 km 10 km

Whiskered bat

Myotis mystacinus ? 2.7 km

Natterer’s bat

Myotis nattereri ? 4 km

Leisler’s bat

Nyctalus leisleri 4.2 km 12.05 km

Noctule

Nyctalus noctula 4.75 km 18 km


Pipistrellus nathusii 6.5 km ?

Common pipistrelle

Pipistrellus pipistrellus 2.1 km 5.05 km

Soprano pipistrelle

Pipistrellus pygmaeus 1.6 km ?


Plecotus auritus 0.5 km 3.15 km

Grey long-eared bat

Plecotus austriacus 2.2 km 5.5 km

Greater horseshoe bat

Rhinolophus ferrumequinum 3.5 km 7 km


Rhinolophus hipposideros 1.9 km 4.4 km

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Richardson P 1985. Nightly dispersal of Daubenton’s bats (Myotis daubentonii) from a

summer roost site. Bat Research News 26(4):71.


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Richardson P 2000. Bats. Whittet Books, Suffolk.

Robinson M & Stebbings R 1997. Home range and habitat use by the serotine bat, Eptesicus

serotinus, in England. J. Zool. London, 243: 117-136.

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Publications, Inc. U.S.A.

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(Chiroptera) occupying the same roost. J. Zool. London, 200: 249-259.

Vaughan N, Jones G & Harris S 1997. Habitat use by bats (Chiroptera) assessed by means

of a broad-band acoustic method. Journal of Applied Ecology, 34: 716-730.

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at two sites in southern Britain. J. Zool. London, 249: 173-180.

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APPENDIX B. RESULTS OF TREE ROOST MAPPING AT RYALL NORTH.

TREE REF No. TN1.5 TN2.1 TN2.2 TN2.3 TN2.5 TN2.7

DATE/S 23/04/14

07/07/14

23/04/14

08/07/14 23/04/14

08/07/14 23/04/14

07/07/14 23/04/14

07/07/14 23/04/14

10/07/14

GRID REFERENCE SO85206-42051 SO85267-42383 SO85309-42368 SO85316-42372 SO85332-42381 SO85352-42269

TREE SPECIES Pedunculate oak Pedunculate oak Pedunculate oak Pedunculate oak Pedunculate oak Pedunculate oak

HABITAT Hedgerow Pasture Pasture Pasture Pasture Pasture

TREE ALIVE/DEAD Alive Alive Alive Alive Alive Alive

TREE HEIGHT 8.5 m 13 m 10 m 11 m 10.5 m 9.5 m

DBH 102.4 cm 108.9 cm 158.1 cm 108.4 cm 113.3 cm 100.1 cm

PRF STEM/LIMB Stem and limb Stem Stem Stem Stem Stem

PRF HEIGHT --- --- ---

Woodpecker hole –

775 cm

Knot-hole – 767 cm

--- 313 cm

PRF FORM Hollow stem

Weld between limbs

Hollow/hole in base

Knot-hole

Hollow bole/ crown

Desiccation fissures

Hollow stem

Woodpecker hole

Knot-hole

Hollow stem


Knot-hole

Hollow bole

DIAMETER AT PRF --- --- --- 61.1 cm --- 92.6 cm

ENTRANCE HEIGHT --- --- --- E – 5 cm W – 22

cm 22 cm

ENTRANCE WIDTH --- --- --- E – 5.5

cm

W – 19

cm 14 cm

DIRECTION Hollow stem – north

Weld – west

Hollow bole – north

Knot-hole – east ---

Woodpecker hole –

east

Knot-hole – west

Knot-hole – west East

INTERNAL HEIGHT --- --- --- 52 cm --- > 1 m

INTERNAL WIDTH --- --- --- 24 cm --- 22 cm

INTERNAL DEPTH --- --- --- 111 cm --- 0 cm

NOTES

Entirely hollow in

bole, weld

discontinuous and

mobile.

Pollard. Hollow in

base and

discontinuous.

Occupied squirrel den

on east side.

Veteran/ancient

pollard. Jackdaw nest

in every hole. All

fissures too small or

open into hollow

crater.

Standard. Loose

lifting bark in crown.

Birds nest in base of

knot-hole. Dome apex

polished in middle

hole.

Standard. Jackdaw

nest in hollow crown.

Knot-hole

discontinuous and

mucky.

Veteran pollard.

Rough internally,

dusty and dry with

chambered apex.

Woodlice and spiders

present.


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NOTES CONT. --- --- ---

Bottom hole squirrel

den with leaves in

base.

--- ---

RE-SURVEY N/A. N/A. N/A.

Re-inspected on

26/08/14 – jackdaw

nest in base, musty

with cobwebs.

Re-inspected on

15/09/14 – musty,

dirty, dusty and rough

with cobwebs and

woodlice.

Re-inspected on

15/09/14 – no

evidence of bats

N/A.

Re-inspected on

26/08/14 – cobwebs,

damp, could be

polished in parts.

Re-inspected on

15/09/14 – apex

cobwebbed with

squirrel fur and barn

owl in bole of tree.

Re-inspected on

15/09/14 – no

evidence of bats


DATE/S 23/04/14 23/04/14 23/04/14

08/07/14

23/04/14

07/07/14

23/04/14

07/07/14

23/04/14

10/07/14

GRID REFERENCE SO85489-42275 SO85490-42267 SO85497-42210 SO85218-42293 SO85034-41779

(Tree tag 0533) SO84930-41806

TREE SPECIES Ash Ash Ash Pedunculate oak Pedunculate oak Pedunculate oak

HABITAT Hedgerow Hedgerow Hedgerow Hedgerow Hedgerow Hedgerow

TREE ALIVE/DEAD Alive Alive Alive Alive Alive Alive

TREE HEIGHT 11 m 9.5 m 10 m 17.5 m 10.5 m 11 m

DBH 54.4 cm 77.5 cm 65.1 cm 128.2 cm 102.8 cm > 1 m (not recorded

due to bosses)

PRF STEM/LIMB Stem Stem Limb Stem Stem Stem

PRF HEIGHT --- --- 6 m --- --- ---

PRF FORM Light ivy cover Light ivy cover Knot-hole on limb

fork

Lifting bark


Occlusion wood

Hollow bole

Desiccation fissures in

canopy

Hollowing

DIAMETER AT PRF --- --- --- --- --- ---

ENTRANCE HEIGHT --- --- --- --- --- ---


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ENTRANCE WIDTH --- --- --- --- --- ---

DIRECTION --- --- West West --- North

INTERNAL HEIGHT --- --- --- --- --- ---

INTERNAL WIDTH --- --- --- 1 cm --- ---

INTERNAL DEPTH --- --- --- 2 cm --- ---

NOTES Standard. Standard. Standard. PRF

discontinuous.

Hedge standard. All

features exposed with

none secluded or

suitable.

Standard. Two nests

in hollow bole. All

desiccation fissures

exposed and shallow.

Standard. Tree holds

numerous features

within the hollow

stem which could

provide shelter.

RE-SURVEY N/A. N/A. N/A. N/A. N/A. N/A.


DATE/S 23/04/14

10/07/14

24/04/14

07/07/14

24/04/14

07/07/14 24/04/14

07/07/14

24/04/14

08/07/14

24/04/14

10/07/14

GRID REFERENCE SO85255-41848 SO84943-41609 SO85026-41548 SO84911-41538 SO85155-41440

(Tree tag 0552) SO85252-41463

TREE SPECIES Pedunculate oak Pedunculate oak Pedunculate oak Pedunculate oak Pedunculate oak Pedunculate oak HABITAT Tillage Hedgerow (tillage) Hedgerow (tillage) Tillage Hedgerow (pasture) Hedgerow (pasture)

TREE ALIVE/DEAD Alive Alive Alive Alive Alive Alive TREE HEIGHT 12.5 m 16.5 m 12.5 m 11 m 22.5 m 14.5 m

DBH 89.3 cm 83.4 cm 201 cm 96.8 cm 115.8 cm 111.5 cm

PRF STEM/LIMB Stem Limb Stem Stem Limb Stem

PRF HEIGHT --- 6 m --- --- Tear-out – 10 m 169 cm

PRF FORM Hollow bole Snag

Hollow stem

Lifting bark


Knot-holes

Lifting bark

Snags

Knot-hole

Split

Tear-out

Basal wound with

large entrance

DIAMETER AT PRF --- --- --- --- Tear-out – 26.4 cm 111.5 cm

ENTRANCE HEIGHT --- --- --- --- Tear-out – 20 cm 33 cm

ENTRANCE WIDTH --- --- --- --- Tear-out – 2.8 cm 12 cm

DIRECTION --- --- --- --- Split – south West


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Tear-out – east

INTERNAL HEIGHT --- --- --- --- Tear-out – 18.5 cm > 1 m

INTERNAL WIDTH --- --- --- --- Tear-out – 3.5 cm 46 cm

INTERNAL DEPTH --- --- --- --- Tear-out – 14.5 cm > 1 m

NOTES Pollard. Hollow bole

open and exposed.

Standard. Snag on

limb 2 m out and an

almost horizontal

hazard-beam feature.

Exposed and almost

full of bird droppings

and feathers in

entrance.

Ancient pollard. Knot-

holes discontinuous

and lifting bark holds

no evidence. All

fissures open into

hollow stem.

Standard. Knot-hole

discontinuous and

lifting bark suitable

but holds no evidence.

Standard. Feature

smells of grass snake,

bumpy and rough

internally and very

clean and dry. Dome

apex shape. Lower

PRF a wet and mucky

trough.

Standard. Internally

wound is rough, dusty

and with debris, but

dry. Dome shaped

apex but no evidence

of bats.

RE-SURVEY N/A. N/A. N/A. N/A.

Re-inspected on

26/08/14 – clean,

polished with faint

grass snake smell,

feather in entrance

with some guano of

unknown type.

Re-inspected on

15/09/14 – clean and

polished with faint

ammonia smell.

Re-inspected on

16/12/14 - clean and

polished with faint

ammonia smell.

Re-inspected on

26/08/14 – dusty with

debris and cobwebs.

Re-inspected on

15/09/14 – no

evidence of bats,

appears to be

passerine night roost.

Re-inspected on

16/12/14 – no

evidence of bats.


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TREE REF No. TN10.8

DATE/S 24/04/14

10/07/14

GRID REFERENCE SO85377-41371

TREE SPECIES Pedunculate oak

HABITAT Hedgerow (pasture)

TREE ALIVE/DEAD Alive

TREE HEIGHT 17.5 m

DBH 115.2 cm

PRF STEM/LIMB Stem

PRF HEIGHT ---

PRF FORM Knot-hole

DIAMETER AT PRF ---

ENTRANCE HEIGHT ---

ENTRANCE WIDTH ---

DIRECTION West

INTERNAL HEIGHT ---

INTERNAL WIDTH ---

INTERNAL DEPTH ---

NOTES Standard. PRF entirely

discontinuous.

RE-SURVEY N/A.


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APPENDIX C. PHOTOGRAPHS OF THE TWO TREES WITH SUITABLE

POTENTIAL ROOST FEATURES WITHIN RYALL NORTH.

Tree TN2.3

Figure C1 below and Photos C1-C3 on the following pages show the location of Potential

Roost Features (PRF) on Tree TN2.3.

Figure C1. The location of Potential Roost Features (PRF) on Tree TN2.3.


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Photo C1. The entrance to the east-facing woodpecker hole on Tree TN2.3.

Photo C2. The entrance to the west-facing knot-hole on Tree TN2.3.


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Photo C3. The domed apex of the internal roosting feature in Tree TN2.3.

Tree TN10.2

Figure C2 on the following page and Photos C4-C5 on the following pages show the

location of PRF on Tree TN10.2.


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Figure C1. The location of the PRF (tear-out) on Tree TN10.2.


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Photo C4. The entrance to the east-facing tear-out on Tree TN10.2.


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Photo C5. The domed apex of the internal roosting feature (tear-out) in Tree TN10.2.

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APPENDIX D. CORRESPONDENCE WITH MS. JULIA HANMER; CHIEF

EXECUTIVE OF THE BAT CONSERVATION TRUST.


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results of a desk-study, habitat ‘truthing’ ryall’s

Documents