Bat Survey Report: Stonehaven Flood Protection Scheme SFPS)

Transcription

1 Specialist Ecological Consultants Lickleyhead Premnay, Insch Aberdeenshire Tel: co.uk Web: www. blackhillecology. co.uk Bat Survey Report: SFPS) CLIENT Mott MacDonald Moray House Bank Street Inverness Black Hill Ecology 2016

2 Control Sheet Report title Client Location Lead ecologist General Report Information Bat Survey Report Mott MacDonald Proposed Report author Black Hill Ecology has prepared this report in accordance with the instructions of their client, Mott MacDonald, for its sole and specific use. No liability is accepted for any costs claims or losses arising from the use of this report or any part thereof for any purpose other than that for which it was specifically prepared or by any party other than Mott MacDonald. This report was prepared by an environmental specialist and does not purport to constitute legal advice. Black Hill Ecology 1

3 Contents A INTRODUCTION... 3 A.1 BACKGROUND... 3 A.2 BAT ECOLOGY... 3 A.3 LEGISLATION... 3 B SURVEY AND SITE ASSESSMENT... 5 B.1 PRE EXISTING INFORMATION ON THE BAT SPECIES AT THE SURVEY SITE... 5 B.2 STATUS OF SPECIES THAT MAY BE ENCOUNTERED... 5 B.2.1 BATS WHICH MAY BE ROOSTING WITHIN THE SITE AND UK STATUS... 5 B.3 OBJECTIVE( S) OF SURVEY... 5 B.4 SURVEY AREA DESCRIPTION... 5 B.5 FIELD SURVEY... 6 B.5.1 METHODS... 6 B.5.2 TIMING... 6 B.5.3 WEATHER CONDITIONS... 6 B.5.4 PERSONNEL... 7 B.6 RESULTS... 7 B.6.1 DAY SURVEY... 7 B.6.2 DUSK SURVEY... 7 B.7 INTERPRETATION AND EVALUATION OF SURVEY RESULTS... 7 B.7.1 PRESENCE/ ABSENCE... 7 B.7.2 SITE STATUS ASSESSMENT COMBINING QUANTITATIVE, QUALITATIVE, FUNCTIONAL AND CONTEXTUAL FACTORS)... 8 B.7.3 CONSTRAINTS FACTORS INFLUENCING SURVEY RESULTS)... 8 C RECOMMENDATIONS AND CONCLUSIONS... 9 C. 1 RECOMMENDATIONS... 9 C. 2 CONCLUSIONS D REFERENCES E APPENDIX... Black Hill Ecology 2

4 A Introduction A.1 Background Black Hill Ecology was commissioned by Mott MacDonald to carry out a bat survey at a proposed development for the SFPS). This report describes the works undertaken during the assessment of possible effects of the development on bats at the specified site. A.2 Bat Ecology There are 17 species of bat currently resident in the UK. Nine species are known from Scotland. All are believed to be in continuing decline as they face many threats to their highly developed and specialised life cycles. In general, their dependence on insects has left them vulnerable to habitat destruction, land drainage, habitat fragmentation, agricultural intensification and increased use of pesticides. Their reliance on buildings and decaying trees has also made them vulnerable to sanitation felling, repairs and the use of timber treatment chemicals. In the UK, bats are generally active from late March to mid October, hibernating from late October to mid March. In early summer, females gather in maternity roosts to give birth, normally producing a single offspring per year. This slow rate of reproduction inhibits repopulation in areas of rapid decline. Bats are generally born in June/ July and are dependent on their mothers for about six weeks. In autumn and winter, male and females gather for mating. The females are able to store sperm until spring when an egg may be fertilized. In winter, bats hibernate in sites that have a cool, humid and stable climate. Bats generally return to the same roost sites every year which makes them particularly vulnerable to disturbance or destruction of these sites. Some species of bat move roost frequently and use a number of different roost sites. A.3 Legislation The information below is intended only as guidance to the legislation relating to these species. The Acts themselves should be referred to for the correct legal wording and legal advice sought where required. All bats are included in Schedule 2 of the Conservation Natural Habitats, c.) Regulations 1994 as amended), which implement the requirements of the Habitats Directive in England, Scotland and Wales. It is an offence for anyone without a license to: Intentionally or recklessly/ deliberately injure, take or kill a bat; To possess a bat unless obtained legally) whether alive or dead; Intentionally or recklessly/ deliberately damage, destroy or obstruct access to any place that bats use for shelter or protection whether bats are present or not; Intentionally or recklessly/ deliberately disturb a bat while it is occupying a structure or place that it uses for shelter or protection. deliberately disturb bats in such a way as to be likely significantly to affect i) the ability of any significant group of bats to survive, breed, or rear or nurture their young; or ii) the local distribution or abundance of that species; Prosecution could result in imprisonment, fines per animal affected and confiscation of vehicles and equipment used. Exemptions can be granted from the protection afforded to bats under the Habitat Regulations, by means of an EPS European Protected Species) Habitats Regulations licence obtained from Scottish Natural Heritage. An EPS Habitats Regulations Licence could be required for: Removal of trees known to be used by bats as well as tree pruning Black Hill Ecology 3

5 Significant alterations to roof voids known to be used by bats Road building or widening Bridge strengthening There are three tests, which must be satisfied, before a licence can be issued to permit otherwise prohibited acts; Regulation 44( 2)(e), for the purpose of preserving public health or public safety or other imperative reasons of overriding public interest including those of a social or economic nature and beneficial consequences of primary importance for the environment; or 44 2)(f) for the purpose of preventing the spread of disease; or 44( 2)(g) for the purpose of preventing serious damage to livestock, foodstuffs for livestock, crops, vegetables, fruit, growing timber or any other forms of property or to fisheries; subject to Scottish Natural Heritage being satisfied that the application additionally meets: Regulation 44( 3)(a) that there is no satisfactory alternative; and Regulation 44(3)(b) that the action authorised will not be detrimental to the maintenance of the species concerned at a favourable conservation status in their natural range. A European Protected Species Licence is required before the commencement of any development that requires one due to its impact on bats or their roosts. Black Hill Ecology 4

6 B Survey and site assessment B.1 Pre existing information on the bat species at the survey site. Within ca. 5km of the site there are six known records of pipistrelle bats Pipistrellus spp.) and four records of Daubenton s bats Myotis daubentonii) 1. Although there are no records of brown long eared bats Plecotus auritus) and Natterer s bats Myotis nattereri) they are known from the region and may also possibly be encountered. B.2 Status of species that may be encountered B.2.1 Bats which may be roosting within the site and UK Status Common pipistrelle Pipistrellus pipistrellus): Locally widespread and common. Nationally widespread and common. Soprano pipistrelle Pipistrellus pygmaeus): Locally widespread and common. Nationally widespread and common. Nathusius pipistrelle Pipistrellus nathusii): Possibly locally widespread but rare. Possibly nationally widespread but rare. Daubenton s bat Myotis daubentonii): Locally widespread and common. Nationally widespread and common. Natterer s bat Myotis nattereri): Locally widespread but not common. Nationally widespread but not common. Brown long eared bat Plecotus auritus): Locally widespread and common. Nationally widespread and common. B.3 Objective( s) of survey The survey set out to assess: a) what species of bat were present at the site; b) what types of bat roosts were found within the site; c) what population levels of bats size and importance) were present or used roosts at the site. B.4 Survey area description The site of the proposed development, SFPS) centred around OS LR: NO ) consists of the built and natural environment adjacent to the lower reaches of the Carron Water from just before its confluence with the Burn of Glaslaw to just before Beach Bridge, and the lower reaches of the Burn of Glaslaw as it exits the Woods of Dunnottar. In the west most point of the survey area the Water of Carron is bordered to the north by suburban gardens and tree lines and to the south by a road and there after broad leaved woodland of the Woods of Dunnottar. As the Water progresses east both banks become more urbanised and built up with the historic old wall along the south bank of the lower section. The built and natural environment of the site is typified by residential buildings bordered by large walls, tree lines, garages and crossed by a single road bridge and multiple foot bridges Figures 1 4). During the Preliminary Ecological Appraisal of the, before Black Hill Ecology s involvement, a ground based bat roost habitat assessment was carried out, the results of which are included as an Appendix to this report and directed this survey to key features that may be used by roosting bats and that were required to be surveyed in more detail. The SFPS is intended to prevent further seasonal flooding associated with the lower reaches of the Carron Water, by the provision of flood defences, necessitating the alteration and/ or removal of nearby built and natural environment. Black Hill Ecology 5

7 Figure 1. SFPS historic wall of lower sections Figure 2. SFPS foot bridge over the river Figure 3. Trees adjacent to river bank Figure 4. SFPS garages adjacent to river bank B.5 Field Survey B. 5.1 Methods On the 12th of July 2016 and the 9th of September 2016 the SFPS area and key features were walked over and surveyed for potential roost sites and signs of bats. The survey utilised binoculars, ladders, tree climbing equipment, endoscopes and high powered torches. The inspection involved looking for bat droppings on the ground, stuck to walls or roof slates/ sheets and on door frames, fixtures and fittings of buildings, bridges and culverts and looking for droppings around and inside tree holes and recording suitable entry and exit points. Close inspection focused on those areas which may be suitable for roosting bats, such as below roof at gable walls, joints and crevices in wood, crevices in walls as well as looking for bat droppings and urine on the walls, floors, tree holes and fixtures. On the nights of the 12th, 13th, 18th, 26th, 27th, 28th of July and the 18th, 26th of August 2016, and the mornings of the 13th, 15th, 28th and 29th of July and 19th, 26th of August 2016, dusk emergence and dawn return surveys were carried out at the SFPS Site to identify and provide a population estimate of any bats present. Each survey location was surveyed three times except the Church which was surveyed on two visits with no indication of use by bats) at a minimum of two week intervals as per BCT guidelines Figure 5). After the emergence surveys concluded transects were also walked over the whole site in order to identify access points, flight paths and alternative roosts used by bats. B. 5.2 Timing On the 12th of July 2016 and the 9th of September 2016 the SFPS area and key features were walked over and surveyed for potential roost sites and signs of bats. On the nights of the 12th, 13th, 18th, 26th, 27th, 28th of July Black Hill Ecology 6

8 and the 18th, 26th of August 2016 emerging bats were surveyed and on the morning of 13th, 15th, 28th and 29th of July and 19th, 26th of August 2016 returning bats were surveyed at the site. B. 5.3 Weather conditions The temperature at the start of the night surveys varied between 13 C and 15 C. There was between 100% and 30% cloud cover and through the survey periods there was little in the way of rain and wind speed varied but was generally low. On the dawn return surveys the temperature was between 11 C and 13 C there was between 100% and 30% cloud cover and wind speed was low. The weather conditions were not considered to impede the surveys in any way and bats were active in numbers during all survey periods. B.5.4 Personnel Work was carried out by licensed bat workers Roost Conservation Licence 44706) with the assistance of experienced ecological surveyors with over five decades of combined experience surveying bats with three to five surveyors working on each survey visit. Figure 5. Plan of SFPS indicating Area Zones and including surveyor locations black circles). B.6 Results B.6.1 Day Survey Internal All internal areas of indicated tree holes, bridges, the garage buildings to be removed and walls to be affected, included in Appendix D, were surveyed for physical evidence of use by bats. All parts were accessible and inspected where safe to do so. No evidence of use was observed in any internal space, cracks or crevices or on any internal fixtures surveyed in the garage buildings or walls surveyed. On the 12th of July 2016 no evidence of use was observed on any bridge or any tree or tree hole. On the 9th of September 2016 evidence of use and bats were observed in crevices in Bridgefield Road Bridge and in tree holes See Species Protection Plan). Black Hill Ecology 7

9 External All external areas of the bridges, trees, garage buildings to be removed and walls to be affected, included in Appendix D, were surveyed for physical evidence of use by bats. All external parts were accessible and inspected. No evidence of use was observed on any of the external structure or in or around any external fixtures surveyed on the bridges, trees, garage buildings or walls surveyed. B.6.2 Dusk/ Dawn Surveys Dusk Emergence Dusk emergence surveys were carried out to visually observe bats emerging from roost sites and if present confirm species identity with the use of a Pettersson D1000x bat detector, Pettersson D980 bat detector, three BatBox Duets and an Ultrasound Advice U30 bat detector and recorders. Surveyors positioned themselves so the site remained in the detection envelope of bat detectors at all times and bats emerging from all aspects would be observed or detected, with surveyors maintaining contact through two way radios Motorola T80s) relaying the time of first contact with bat species and info on bat activity to determine whether bats emerged from roosts on site or travelled down the river catchment to observer locations. Thirty minutes before sunset on survey nights no social calls from roosting bats could be heard from any part of the built or natural environment at the except from the building roost Roost A) adjacent to the Glaslaw Burn See Species Protection Plan). The emergence surveys began 15 mins before sunset and continued for one and a half hours after sunset. Common pipistrelles, Pipistrellus pipistrellus, were usually the first bats to emerge or arrive on the lower sections of the Carron Water surveyed, but in low numbers. Soprano pipistrelles, Pipistrellus pygmaeus, were observed in high numbers maximum count 134 individuals, Roost A) emerging from a dwelling adjacent to the Burn of Glaslaw and then heard in greater numbers further downstream as the evening progressed. On the 13th of July 2016 two pipistrelle bats, identified as Pipistrellus pipistrellus by the peak frequency of echolocation calls recorded, emerged from under slates in the building adjacent to the Bridgefield Road Bridge See Species Protection Plan, Roost B) and on the 26th of August 2016 three pipistrelle bats, identified as Pipistrellus pygmaeus by the peak frequency of echolocation calls recorded, emerged from a tree hole in a dead elm near the red bridge See Species Protection Plan, Roost C). Commuting and feeding bats were recorded across the site throughout the survey periods e.g. Figure 6 and 7) and on several occasions bats were observed to alight on the old wall both up and downstream of the Bridgefield Road Bridge. Dawn Return Dawn return surveys were carried out to visually observe bats returning to roost sites and if present confirm species identity. The dawn return surveys began one and a half hours before sunrise and continued until sunrise or ten minutes after the last bat returned. On the 19th of August 2016 bats were observed to swarm around the entrance to the building Roost A) by the burn of Glaslaw and also several individual bats were observed to circle a dead tree nearby occasionally alighting on the trunk before flying off See Species Protection Plan, Roost D). On the 26th of August 2016 a single pipistrelle bat, identified as Pipistrellus pipistrellus by the peak frequency of echolocation calls, returned to roost in the Bridgefield Road Bridge See Species Protection Plan, Roost E). Figure 6. Echolocation calls of commuting P. pipistrellus Figure 7. Calls of a feeding bat P. pipistrellus Black Hill Ecology 8

10 B.7 Interpretation and evaluation of survey results B. 7.1 Presence/ absence The survey observed and recorded bats using roosts at the site of the proposed Stonehaven Flood Protection Scheme SFPS). The locations of the roosts accessed are detailed in the Species Protection Plan. Occasionally bats were also observed to alight on the Old Wall adjacent to the Carron Water. Furthermore, a dead tree near Roost A was considered a roost site due to activity and behaviour of bats observed near by Roost D). No bats or signs of bats roosting were observed or recorded at any other part of the built or natural environment at the however, during all bat detector surveys the river and riparian habitat was used extensively on both mornings and the evening surveys by at least two species of bat Pipistrellus pipistrellus, P. pygmaeus). Bats therefore may be present in any suitable gaps available on site. B.7.2 Site status assessment combining quantitative, qualitative, functional and contextual factors) A low number 4 individuals maximum count) of two species of pipistrelle bats Pipistrellus pipistrellus, Pipistrellus pygmaeus) were confirmed to use structures that are indicated to be directly affected by the proposed See Species Protection Plan) as roost sites. The two sites are Roost C and Roost E). It is likely that a low number of non reproductive female or male bats use the sites identified, that are indicated to be directly affected, as day roosts. There was also extensive activity of these two bat species across the site including around further structures that contained suitable roost sites such as the historic Old Wall, culverts and trees and although not confirmed as roost sites, these sites could potentially be used by roosting bats See Species Protection Plan). Furthermore a number of roost sites were adjacent to the site and although not directly affected by the current proposed works in relation to the SFPS contribute to the site assessment and require consideration in any species protection plan method statement. The site and its buffer are therefore considered to have ecological value in relation to use by bats. Each roost and its characterisation and likely impact under the current proposals for the SFPS are detailed in Table 1. Table 1. Likely impact on Bat roosts identified and characterised Species Roost Type by species and type Roost Location Number of Bats Roost A P. pygmaeus Maternity Dwelling 134 Low Roost B P. pipistrellus Non-maternity day roost Dwelling 2 Low Roost C P. pygmaeus Non-maternity day roost Tree 3 High Impact Roost D P. pygmaeus Non-maternity day roost Tree 2 Medium Roost E P. pipistrellus Non-maternity day roost Bridge 1 High B.7.3 Constraints factors influencing survey results) There were few constraints to close inspection of the site although one hazard tree with suitable roost habitat was considered unsafe to climb) and weather conditions were acceptable for roost characterisation surveys as per BCT guidelines in order to provide the further information required to inform a licensing decision. C Recommendations and Conclusions C. 1 Recommendations The survey demonstrates that the area considered for the is used extensively by foraging and commuting bats and manmade and natural structures that will be impacted were identified as roost sites by a low number of two species of bat. The bat species concerned are nationally widespread and common. The proposed development intends to prevent further seasonal flooding Black Hill Ecology 9

11 associated with the lower reaches of the Carron Water, by the provision of flood defences, necessitating the alteration and/ or removal of nearby built and natural environment features. If the Stonehaven Flood Protection Scheme is carried out as proposed it will result in the destruction of Pipistrellus pipistrellus and Pipistrellus pygmaeus non maternity day roosts used by at least four bats. Bat populations usually have a number of non maternity day roost sites in a given area and the loss of a low number of sites used by few bats is likely to have a low impact at an individual bat and at the population level. All bats and bat roosts places that bats use for shelter or protection) are protected under current legislation and therefore an EPS European Protected Species) licence issued by Scottish Natural Heritage is required to destroy/ disturb the existing roost site. No works that might disturb roost sites or roosting bats should be commenced until an EPS licence has been obtained. Scottish Natural Heritage SNH) states that an indication of the time to process an application will likely be under 15 days from the date of receipt of all information based on current turn around time). An application form and further details can be obtained from: Licensing Section, Scottish Natural Heritage, Great Glen House, Leachkin Road, Inverness, IV3 8NW. If a licence to destroy the roosts is pursued a detailed specified species protection plan and method statement detailing proposed works should be development with the assistance of a licensed ecologist taking into account the roost type and the status of the species at the local, regional and national level. If pursued with mitigation it is unlikely that the works would have a detrimental effect on the conservation status of the bat species concerned. Bats change roosts both within and between years and frequently use different structures as roost sites in different seasons. Despite the lack of any further confirmed bat roost sites, even after a full summer survey to BCT guidelines, in an area with such extensive bat activity and where many suitable structures such as bridges a known preferred roosting structure for the bat species identified) and walls with attached outbuildings is concerned there is still a likelihood that other parts of the site may be used by roosting bats. Furthermore, bats may use different parts of the site during the winter to hibernate and would be particularly at risk at this time. It is therefore recommended that a detailed method statement and auditable system of ecological site monitoring, including a schedule of specific site events and mitigation and compensation measures to ensure the protection of bats is developed and supervised by a suitably qualified ecologist and recorded for inspection by the Local Authority. If the period of time between this survey and commencement of development work extends to a further bats breeding season another survey to identify use of sites is recommended to ascertain any changes in bat usage before work commences. As bats change roosts regularly there presence at a different location on the site in the future cannot be completely ruled out. In the event that bats are encountered during other works, all works should cease and Scottish Natural Heritage or a licensed ecologist contacted. C. 2 Conclusions Two species of bat were found roosting on site and their roosting sites will be affected by the development. Appropriate mitigation and compensation would allow the development to proceed without a significantly detrimental effect on local bat populations. An EPS licence will be required to carry out works. D References Bat Records for Scotland Scottish Natural Heritage1. Harris, S. Yalden, D Mammals of the British Isles. 4th Edition. The Mammal Society. Collins, J. 2016). Bat Surveys for Professional Ecologists: Good Practice Guidelines. 3rd Edition. Bat Conservation Trust, London. Mitchell Jones, A. J. 2004) Bat Mitigation Guidelines. English Nature, Peterborough. Black Hill Ecology 10