Rules and Guidelines for Bat Roost Architecture in the Urban Context Technical Studies (ETS 5) 2019/2020
Joyce Ka Kei Ng
2
Table of Contents An Introduction 1. Thesis 2. Technical Ambition
Part 1: Hooke Park
Part 3: Beyond Hooke Park
1. An Ancient Woodland
1. Hooke Park as an Initial Site of Exploration
2. An Environmental Overview
2. Threats to Bat Species
3. An Ecological Overview
3. Bats and Other ‘Building-reliant Species’
4. The Woodland Management Plan
4. Playing with the Rules of Architecture: Rural vs. Urban
5. A Need for Wildlife Monitoring
5. Bats in the Urban Context
5.1 A Case Study: Wytham Woods, Oxford
5.1 Permitted Development (PD) 2012
5.2 Wildlife Monitoring Program in Hooke Park
5.2 Passive House
5.3 Wildlife Monitoring in Hooke Park and Beyond
5.3 Bats and Artificial Lighting
About Bats
6. Bats in London
1. Information on Bats
6.1 Distribution of Bat Species in London
6.2 Monitoring Bats in London
6.3 Wild West End: An Ecological Initiative in Central London
1.1 Bat Species
1.1.1
List of UK Bat Species
1.1.2
Distribution of Bat Species in Dorset
1.1.3
Biology and Behavior
1.2 Life of a Bat in a Year
1.3 Importance of Bats
Part 4: Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
1.4 Bats and the Law
1. Considerations for Bat Roost Architecture in New and Existing Buildings of
1.5 Bats and Architecture
London
2. Bats in Hooke Park
2. Interventions in an Existing Building: The Architectural Association, Bedford
Square
2.1 Bat Species of Hooke Park
3. Bat Monitoring
2.1 Solar Analysis of Building Volume
3.1 Basic Requirements for Bat Monitoring
2.2 The Two Interventions: Barrel Vault and 34 Bedford Sqaure
3.2 Bat Monitoring Program in Hooke Park
2.3 Barrel Vault
3.2.1
Participants of the Monitoring Program
2.3.1 Temperature and Heat Flux Study
3.2.2
A Monitoring Transect
2.3.2 Bat Roost Design
3.2.3
Long-term Vision
2.3.3 Temperature and Heat Flux Study for Design
2.4 34 Bedford Square
Part 2: Rules and Guidelines for Bat Roost Architecture
2.4.1 Temperature and Heat Flux Study
2.4.2 Bat Roost Design
2.4.3 Temperature and Heat Flux Study for Design
1. Information on Bat Roosts
3. Intervention in New Building: A Residential Project at Farncombe Street
1.1 Bat Roost Typology
3.1 Solar Analysis of Building Volume
1.2 Bat Roost Preferences of UK Bat Species
3.2 The Area of Intervention Within Building
2. A Case Study: Existing Bat Roosts of Hooke Park
3.2.1 Temperature and Heat Flux Study
3.2.2 Bat Roost Design
2.1 The Campus
2.1.1
The Big Shed
3.2.3 Temperature and Heat Flux Study for Design
2.1.2
Westminster Lodge The Caretaker’s House
3.2.4 Bat Roost Design 2
2.1.3
The Caretaker’s House
3.2.5 Temperature and Heat Flux Study for Design 2
3. Methods of Incorporating Bat Roosts into Architecture 4. Existing Ready-made Products
Contacts
5. Bat Roost for Crevice-Dwelling Bats 6. Playing with the Rules of Architecture
References
3
An Introduction 1. Thesis
This project begins in Hooke Park as an initial site of exploration. The exploration brings to light the presence of wildlife, an undervalued ecological aspect of the woods. In fact, Hooke Park, an oddly shaped piece of land, is a part of the two percent of rare ancient woodland that still exists in the United Kingdom. It provides a crucial habitat for a range of wildlife, including the ones that are undiscovered and rare. Wildlife such as bats, owls and bees are unique and crucial to the local woodland biodiversity and have never been studied or monitored at Hooke Park. Christopher Sadd, the Hooke Park Forester, highlighted in the Woodland Management Plan of 2014 that the surveying and monitoring of wildlife is important in order to maintain the health of the woodlands but it has never been implemented in a larger scale within Hooke Park. Through a series of discussions and research, bats became the focus of this project as it became apparent that it is possible to monitor bats as a biodiversity indicator and it also has an interesting relationship with manmade architecture. The study of bats and its relationship with architecture in Hooke Park led to more questions about where bats choose to live within human built structures and how they navigate and use the surrounding greenery. The study of the campus unravels an intricate system that seems to extend beyond Hooke Park itself. In fact, bat roosts can be found all over the country from rural to urban environments. And as more natural landscapes such as woodlands continue to disappear, species that rely on built structures (also known as ‘building-reliant species’) migrate and find accomdation in more urban areas. This brought the research into the urban context. How does architecture today consider and accommodate these ‘building-reliant species’? The aim of this study is to compile the rules and guidelines of bat roost architecture and show how it can be applied it into two types of buildings in the urban context: One existing building at Bedford Sqaure, and one new building at Farncome Street, both buildings situated in London.
4
Aerial Photograph of the Hooke Park campus buildings surrounded by woodland. Photo taken in March 2020 by Ke Yang and Joyce Ng.
An Introduction
5
An Introduction 2. Technical Ambition
The technical ambition is to compile various research and documentations to create a rules and guidelines for bat roost architecture in the UK and then apply it into two exisiting buildings as a test. Simply put, the structure of this technical study is in divided into two: 1.
Technical Research:
The aim is to compile the rules and guidelines for bat roost architecture.
11.
Technical Design:
The aim is to apply the rules and guidelines for bat roost architecture.
The visual diagram on the right shows the structure of techincal study. It illustrates the topics covered in within the technical research and the technical design.
6
Part 1
Hooke Park
Identify the Indicators of Biodiversity
Birds?
Bees? Bats
Importance of Conservation and Monitoring Part 2
Technical Research
Rules and Guidelines for Bat Roost Architecture
Hooke Park Case Study
A Bat Roost for Crevice-Dwelling Bats
Bat Monitoring Roost for Hooke Park Playing with the Rules of Architecture Part 3 Beyond Hooke Park
Increase of Building-Reliant Species
Architecture in the Urban Context: London Part 4
Technical Design
Application of Rules and Guidelines for Bat Roost Architecture
Intervention in an Existing Building
Intervention in a New Building
Technical Design of Bedford Square
Technical Design of Farncombe Street
An Introduction
7
8
Part 1 Hooke Park 1. An Ancient Woodland 2. An Environmental Overview 3. An Ecological Overview 4. The Woodland Management Plan 5. A Need for Wildlife Monitoring
5.1 A Case Study: Wytham Woods, Oxford
5.2 Wildlife Monitoring Program in Hooke Park
5.3 Wildlife Monitoring in Hooke Park and Beyond
About Bats 1. Information on Bats
1.1 Bat Species
1.1.1
List of UK Bat Species
1.1.2
Distribution of Bat Species in Dorset
1.1.3
Biology and Behavior
1.2 Life of a Bat in a Year
1.3 Importance of Bats
1.4 Bats and the Law
1.5 Bats and Architecture
2. Bats in Hooke Park
2.1 Bat Species of Hooke Park
3. Bat Monitoring
3.1 Basic Requirements for Bat Monitoring
3.2 Bat Monitoring Program in Hooke Park
3.2.1
Participants of the Monitoring Program
3.2.2
A Monitoring Transect
3.2.3
Long-term Vision
9
Hooke Park 1. An Ancient Woodland
In the United Kingdom, only 2% of land cover is considered to be ancient woodland. In 1086, Britain was 15% forested, which dropped to 5% by 1900 at the height of the industrial age. Today, Hooke Park is a part of the 2% of the ancient woodland in the United Kingdom that still exists. Hooke Park is categorised as ancient semi-natural woodland. Ancient semi-natural woods are woods that have developed naturally. Most have been used by humans – often managed for timber and other industries over the centuries – but they have had woodland cover for over 400 years. Ancient woods are the richest and most complex terrestrial habitat in the UK and they are home to more threatened species than any other. Centuries of undisturbed soils and accumulated decaying wood have created the perfect place for communities of fungi and invertebrates. Other specialist species of insects, birds and mammals rely on ancient woodlands. It’s an important, irreplaceable habitat and in sore need of protection. In 1947, Hooke Park was cleared of 90% of its trees to feed the desperate post-war shortage of timber. It was replanted in the early 1950s with a mixture of Beech (fagus sylvetica) and Norway Spruce (picea abies) with some oak and remnant fragments of alder, willow, and hazel. Beech was an important commercial species feeding the large volume UK furniture manufacturers of the time, whilst Norway Spruce is the leading structural and general use timber throughout Europe. Although 90% of its trees were cleared, the soil on Hooke Park’s land is still rich soil found in ancient woodlands, therefore marking this piece of land a part of the percentage of woodlands found in the UK. The Parnham Trust purchased Hooke Park in 1983 and started the negotiation for planning permission to build an educational and residential faculty in the woods. Today, Hooke Park belongs to the Architectural Association and it is working towards the transformation of the wood from an even-age structure to a mixed-age woodland, of greater aesthetic and biodiversity value.
10
Photograph of the Hooke Park woodlands. Photo taken in November 2019 by Ke Yang.
Hooke Park
11
Hooke Park 2. An Environmental Overview
Hooke Park is the Architectural Association’s ancient woodland campus located in Dorset, southwest England. Surrounded by countryside farmland, the 150-hectare working forest. At the core of the woodland, it contains a growing campus accomodating an educational facility for design, workshop, construction, and landscape-focused activities. Hooke Park’s campus and woodland accommodates a number of built projects, produced by the Design & Make programme, visiting schools, summer workshops, and AA students. The buildings on camps are known to be the primary and permanent structures of Hooke Park, whilst the buildings in the woodlands are knwon to be secondary and temporary structures of Hooke Park. These temporary secondary structures are either taken down or left to decompose over time. The exploratory map, as shown on the right, marks both the primary and secondary structures that still exist in the woodlands today. Beyond the campus, woodland is also guided by roads, small trails, ponds and streams. Hooke Park’s highest elevation is at 215m (Northeast of Hooke Park) and its lowest elevation at 108m (Southwest of Hooke Park). The streams that run through the woodland carries top soil, clay and silt from the Northeast landscapes to the farmlands of Southwest of Hooke Park. In the wooded areas, it consists of 15 mapped tree species within the boundaries of Hooke Park, all of which are separated into divisions which is illustrated on the map, shown on the right. The two most dominating being the Beech and the Norway Spruce. Each cluster succeeds in formulating its own environment, creating a plethora of different conditions to explore through the seasons.
12
There are 15 mapped tree species within the boundaries of Hooke Park, the two most dominating being the Beech and the Norway Spruce. Each cluster succeeds in formulating its own environment, creating a plethora of different conditions to explore through the seasons.
AS
Ash
BE
Beech
OA
Oak
SY
Sycamore
NS
Norway Spruce
DF
Douglas Fir
RO
Red Oak
MB
Mixed Broadleaf
SC
Sweet Chestnut
CP
Corsican Pine
PO
Poplar
RC
Red Cedar
AL
Alder
LA
Larch
SS
Sitka Spruce Woodland boundary Hooke Park woodland boundary Trails/Roads Waterways Hooke Park primary structures Hooke Park secondary structures
TREE SPECIES MAP Ele Mun, 2019
Source: Hooke Park, Zachary Mollica
N
Map of Hooke Park, indicatimg the tree species, woodland boundaries, roads, trails, waterways and structures.
Hooke Park
13
Hooke Park 3. An Ecological Overview
Hooke Park’s fauna play a significant role in the wellbeing of the woodlands. It hosts a range of large animals from deer, foxes, badgers, birds, bats, squirrels and mice. There are also moths, butterflies and other types of insect species that are native to Hooke Park. Hooke Park is known to have a variety of insect species, which feed the larger animals of Hooke Park, but they have yet to be fully studied. According to the long-time staff from both Bedford Square and Hooke Park, Hooke Park’s ecological landscape have changed drastically in the last twenty years since been acquired by the Architectural Association. Miraj Ahmed, a diploma tutor, shared that twenty years ago, wild boars and deer would commonly be found roaming in the campus and in the woodlands.Today, students who visit Hooke Park will unlikely stumble upon a wild boar or deer sighting as they are rather rare. This is one of many examples of wildlife loss in Hooke Park and proves the utmost importance to monitor and conserve the rare and unique environment that the Architectural Association still holds today. Monitoring biodiversity indicators are widely accepted to be an excellent way to report on general trends not just within wildlife populations but also on the state of the environment. It can be helpful for the forester of Hooke Park, the foresters of surrounding woodland as well as for data collection for scientific research contributions. There are many wildlife animals that can be monitored but according to ‘UK Biodiveristy Indicators 2019’, the most commonly monitored wildlife in the woodlands are: Birds, bats and insects. Each of these wildlife species falls under different categories of the Ecological Pyramid of Numbers. By monitoring from these different categories, it could help gain a better understanding of biodiversity. The pyramid of numbers, represented below, shows the population of Hooke Park, in terms of the number of individual organisms involved at each level in a food chain.
TC
Owl, Buzzard, Fox SC
Squirrel, Tit, Pheasant, Deer, Dormice, Bats, Badger
PC
Insect (Bees, Moths, Butterflies), Fungi
PP
Grass, Roots, Barks, Trees
14
A still image from the footage captured in Hooke Park on the Bushnell Camera Trap of a wandering deer and fox. Footage captured in December 2019.
Hooke Park
15
Hooke Park 3. An Ecological Overview
TC
Buzzard
SC
Bats
Tit SC
TC
Fox
Squirrel SC
D
16
TC
Owl
TC
Forester Deer SC
Bark PP
Insects
Dormice
PC
SC
Grass
Badger
PP
SC
Fungi PC
Pheasant Roots
SC
PP
Hooke Park’s Ecological Pyramid of Numbers TC
Tietary Consumers
SC
Secondary Consumers
PC
Primary Consumers
PP
Primary Producers
The illustration is of Hooke Park’s not-commonly-seen wildlife. The arrows indicating the food chain of the woodland; the letters indicating which group the animal falls into the Ecological Pyramid.
Hooke Park
17
Hooke Park 4. The Woodland Managment Plan
Under the guidance of the Forest commission, Hooke Park has a written and documented woodland managment plan. The lastest woodland management plan of 2014 highlights the need for surveying and monitoring programs. It states in various parts of the document: “The AA sees itself as the custodian of a special place where its activities must safeguard its landscape, ecological richness, recreational and amenity value but also manage the wood as a source of timber” In the ‘Management objectives’, it aims “1. to produce a sustainable supply of fuel wood and timber, 2. to conserve and enhance the existing wildlife communities by maintianing and increasing habitat biodiversity.” And under the section ‘Protecting and enhancing landscape, biodiversity and special features’, it aims to “instigate survey and monitoring projects via local conservation groups, eg. erection of bird boxes” But since the approved Woodland Management Plan of 2014, there hasn’t been much done to push this program further. Most of which is due to logistical reasons and lack of man power. It proved that Hooke Park needed to push forward the idea and intention to create a more well manged woodland that strives to increase biodiversity beyond the aim for timber production. Through conversations with Christopher Sadd (Hooke Park forester) and Stephen Hales (Wildlife Expert), it was suggested that the three biodiversity indicator species that would be appropriate to monitor in Hooke Park would be: Owls, Bats, or Bees.
TC
Owl, Buzzard, Fox SC
Squirrel, Tit, Pheasant, Deer, Dormice, Bats, Badger
PC
Insect (Bees, Moths, Butterflies), Fungi
PP
Grass, Roots, Barks, Trees
18
A page from the Woodland Management Plan of 2014. This document mentions intended measures to protect and enhance biodiversity: measures have yet to be put in place.
Hooke Park
19
Hooke Park 5. A Need for Wildlife Monitoring
5.1 A Case Study: Wytham Woods, Oxford
To gain a better understanding of what it means to monitor wildlife in the wood-
for AA student, staff and interested external participants to help and contribute
lands, Diploma 18 paid a visit to Wytham Woods, the woodland campus of the
to the studies of the woodland. The AA institutional body needs to ask themselves
University of Oxford.
what kind of woodland they wish Hooke Park to be?
“Wytham Woods is an ancient semi-natural woodland, which has been owned and
There is also a book published by the University of Oxford, shown in the image
maintained by the University of Oxford since 1942. Its 1000 acres are a designated
below, that explores the role of Wytham Woods within the university and the
Site of Special Scientific Interest and are one of the most researched pieces of
research projects that have been conducted within the woods.
woodland in the world, exceptionally rich in flora and fauna, with over 500 species of plants, a wealth of woodland habitats, and 800 species of butterflies and moths. The Woods can be divided into four main habitats. The forested area is a simple three-way split between ancient semi-natural woodland, secondary woodland and modern plantations. The fourth key habitat is the limestone grassland found at the top of the hill. Other smaller habitats include a valley-side mire and a series of ponds. The ancient woods date back to the last Ice Age, while the secondary woodland dates to the seventeenth century and the plantations to the 1950s and 1960s. The Woods are enjoyed by walkers, wildlife enthusiasts, and school children, and used by researchers both from the University and around the world for wildlife and environmental research, some of which provides data going back several decades.”
The drawings on the right, Wytham woods is about 2.5 times bigger than Hooke
(University of Oxford, 2020)
Park. It consists of four habitats, one of which is grassland which is not found in Hooke Park. Currently, Hooke Park is used to cater to architectural research and
The wildlife of Wytham Woods is similar to the wildlife of Hooke Park consider-
projects, and is open to the public for walks. However, there is potential to open
ing that they are both woodland landscape. They both have deer, badgers, foxes,
Hooke Park to cater to conservation and scientific interest.
squirrels, birds, and more. However, there are also local species that are unique to each of the woodland habitats. For example, there may be fungi that is Hooke Park that isn’t found in Wytham Woods or there are bat species that would only forage a 1km radius within Hooke Park. During conversations with Nick Tomlinson , the bat expert, and Jo Ferguson, the Built Environment Officer of the Bat Conservation Trust, they made it clear that future research is essential in understanding how to better conserve these environments. Therefore, studies of many different woodlands from different parts of the country is crucial for scientific interest and conservation. During the tour of Wytham Woods with Nigel Fisher, the Wytham Woods Conservator, he showed us around the woodlands and explained how the woodland goes through many phases and discussions as to what kind of woodland the univeristy wishes Wytham woods to be. For example, should the woodland be more colourful to cater to the flora studies? Or should the woodland be more dull for fungi studies? As for the individual studies, he showed us around the human interventions created for research studies (as shown in the following page). Under the operation of the Architectural Association, there is currently no extensive study conducted for any of the wildlife species. Given that Hooke Park consists of 150 hectares of land, it is completely possible to set a program in place
20
N
Wytham Woods, University of Oxford Woodland size: 400 hectares Woodland Type: Semi-Natural and Replanted Woodland
N
Hooke Park, Architectural Association Woodland size: 150 hectares Woodland Type: Semi-Natural and Replanted Woodland
The two images above is a comparison between Wytham Woods and Hooke Park in size and area.They are both semi-natural and replanted ancient woodland, similar in landscape.
Hooke Park
21
Hooke Park 5. A Need for Wildlife Monitoring
22
5.1 A Case Study: Wytham Woods, Oxford
1
2
Light weight, coloured flag poles positioned within Wythan Woods to mark a grid for tracking mice. Photo taken in January 2020.
A Schwegler woodcrete bird box, usually occupied by tit or bat species (Noctule and Pipistrelle). Photo taken in Janurary 2020.
3
A temporary tent set up with an interior night light to attract and capture insects for scientific research. Photo taken in January 2020.
4
A scaffolding structure used to study caterpillars, butterflies and birds among the trees. Photo taken in January 2020.
2 3
1
4
Top row images: Photos of human intervention taken at Wytham Woods during a tour with Nigel Fisher, the woodland conservator. Below: Map of Wytham Woods indicating location of photos taken.
Hooke Park
23
Hooke Park 5. A Need for Wildlife Monitoring
5.1 A Case Study: Wytham Woods, Oxford
Of the many wildlife speices that Wytham Woods studies, bats is one of the species that they do study. “Since 2006, Danielle Linton, a bat researcher of the University of Oxford, has been coordinating groups of volunteers to check the EGI bird boxes in Wytham Woods looking for bat roosts. Over 21,000 box checks of the 1265 Schwegler boxes have resulted in over 1000 roosts (>80% boxes used to date) being recorded. Three species regularly form maternity colonies in the boxes: Myotis daubentonii, Myotis nattereri and Plecotus auritus, and seven species have been found in boxes at Wytham so far... Over 3000 individual bats have been ringed in nine years and this study has revealed much valuable information on bat social networks, colony home roost ranges and population dynamics at this site. Following individual life histories and monitoring juvenile health (size and survivorship) per annum also provides some
This scene shows Danielle Linton carefully lowering the bat box.
fascinating insights.” (Warwickshire Bat Group, 2014) Danielle Linton has gone on to write many papers about her studies of Wytham Wood’s bats. In one of the papers she collaborated in, “Sympatric Woodland Myotis Bats Form Tight-Knit Social Groups with Exclusive Roost Home Ranges” by Tom A. August, Miles A. Nunn, Amy G. Fensome, Danielle M. Linton, Fiona Mathews, it shows an example of how the social structure and behavior could be studied by placing roosts around the woodland and individually tagging them. The visual diagram on the right is the a visual representation of their study described in their paper. It illustrates the distribution of M. nattereri (both male and female) and M. daubentonii (female) social groups in Wytham Woods. Linton has also been in a documentary video called “Bats at Wytham” that shows
This scene shows a colony of Natterer’s bat in the bat box.
how the bats are tagged, weighted, measured, for her larger data collection of Wytham Wood’s bats. Wytham Woods is a woodland that heavily focuses on scientific research. Hooke Park, although part of an architectural school that caters to creating and building, it can also play a larger role in connecting the academic and research community through architecture, science and beyond. In fact, the study of woodland bats is one topic that has not been studied enough, therefore there is much more that Hooke Park can contribute to in a larger context.
This scene shows Danielle Linton and Denise Foster checking the tagged bats.
“Bats at Wytham Woods”: The documentary shows bat box checks with Danielle Lindon and Denise Foster conducted in 2014. The bat box checks are a part of a larger data collection project for bats.
24
Social Networks of Social Networks of Woodland Bats
Social Networks of Wood
Woodland area
Boxes used by 2 or more bats Boxes used by a single bat Roost used by two social groups Estimated female roost ranges Radio-tracking fixes
Distribution of M. nattereri (female and male)
Social Networks of Social Networks of Woodland Bats
PLOS ONE | www.plosone.org
5
October 2014 | Volume 9 | Issue 10 | e112225
Woodland area Boxes used by 2 or more bats Boxes used by a single bat Roost used by two social groups Estimated female roost ranges Radio-tracking fixes
PLOS ONE | www.plosone.org
5
October 2014 | Volume 9 | Issue
Female M.daubentonii social groups in Wytham Woods. PLOS ONE | www.plosone.org
5 PLOS ONE | www.plosone.org
October 2014 | Volume 9 | Issue 10 | 5
October 2014 | Volume 9 | Issue 10 | e112225
The two images above are diagrams produced by the scientists from the paper “Sympatric Woodland Myotis Bats Form Tight-Knit Social Groups with Exclusive Roost Home Ranges”, published in 2014.
Hooke Park
25
Hooke Park 5. A Need for Wildlife Monitoring
5.2 Wildlife Monitoring Program in Hooke Park
Back at Hooke Park, Diploma 18 spoke to Chrisopher Sadd, theHooke Park forester, and Stephen Hales. Stephen Hales was introduced to our unit because of his vast knowledge of Hooke Park’s wildlife. Turns out, he has been independently monitoring moths in Hooke Park for the last 30 years. It was through the discussion with Chris and Steve that it was decided that the three wildlife species that would be benefitial to monitor in Hooke Park would be owls, bats and bees. As mentioned previously, the particular interest in bats was due to its relationship with architecture but futhermore, bat populations utilise a range of habitats across the landscape and are sensitive to the pressures in the urban, suburban and rural environment which makes it particularly important to monitor to understand our changing environment. Though UK bat species have made slight recoveries in recent years, bat populations, especially the rare and threatened species remain vulnerable.The pressures that the bat populations face such as landscape (air and water quality) changes, agricultural intensifications, architectural and infrastructural developments, and habitat fragmentations are very much relevant today. Through discussions with Chris, Steve as well as Nigel, it was understood that they best way to monitor wildlife was to idenitfy a transect in which participants can record data in consistent paths and points. This would make for a more reliable data and will be benefitial to observe changes alone the same path over time. The map on the right indicates two sample transects drawn up based on the information provided by Steve, Chris, and other supporting documents from the Bat Conservation Trust and more. There are two sample transects: one for bird monitoring and one for bat monitoring.The key in identifying a good transect is to find a path the passes through various environments within the woodlands that would be considered ideal for the particular species. For exmaple, to identify a bat monitoring transect, it would be useful for the path to pass through areas with mixed tree species, areas with older trees, areas with water bodies, paths with obvious tree lines (as bats tend to follow the lines of landscapes), as well as the campus (in which we know bats are present in that area). In the map, you will notice that the transect follows a path that intersects all these environments mentioned above.
A photo of the lecture with Stephen Hales. Stephen has been a visitor of Hooke Park for the last 30 years. He has been independently monitoring both common and rare moth species in Hooke Park.
26
There are 15 mapped tree species within the boundaries of Hooke Park, the two most dominating being the Beech and the Norway Spruce. Each cluster succeeds in formulating its own environment, creating a plethora of different conditions to explore through the seasons.
AS
Ash
BE
Beech
OA
Oak
SY
Sycamore
NS
Norway Spruce
DF
Douglas Fir
RO
Red Oak
MB
Mixed Broadleaf
SC
Sweet Chestnut
CP
Corsican Pine
PO
Poplar
RC
Red Cedar
AL
Alder
LA
Larch
SS
Sitka Spruce Woodland boundary Hooke Park woodland boundary Trails/Roads Waterways Hooke Park primary structures Hooke Park secondary structures Bird Transect Bat Transect
TREE SPECIES MAP Ele Mun, 2019
Source: Hooke Park, Zachary Mollica
N
Map of Hooke Park, indicating the tree species, woodland boundaries, roads, trails, waterways, structures and two example transects; one for birds and one for bats.
Hooke Park
27
Hooke Park 5. A Need for Wildlife Monitoring
5.3 Wildlife Monitoring Program in Hooke Park and Beyond
As mentioned previously, there are bat species (as well as other woodland wildlife species) that live locally, regionally or intercontinentally. Bats that live in all of these territorial scales experience different kinds of changes and threats over time and in order to conserve and protect these species, monitoring Hooke Park will provide a more wholistic picture of the changes in bat populations which could further inform the positive and negative changes in environment and ecology. Some bat species that live locally travel within 1km. Therefore, if the surrounding landscape experiences drastic changes such as tree felling or new building developments within their territory, these bat species will be in great trouble. In fact, many of these local bat species are the rarer kinds and are under serious threat. The bat species that travel regionally and beyond experience other challenges. The woodland area of the UK has become more fragmented, especially in the last century. This makes it more challenging to travel from one woodland to another for roosting and foraging. Additionally, the vast farmlands that have taken over what use to be natural woodlands, are high risk areas for bats. Firstly, tree lines, hedgerows, trails and roads are landscape elements that bats use a navigational tools. However, these elements can lead them to dangerous areas such as windmills and motorways. Secondly, agricultural land such as vegetable farms may spray pesticides that are harmful to bats when they are hunting for insects. Thridly, vast clear landscapes are also makes it easy for predatory birds to prey on migrating bats. The map on the right indicates the ancient woodlands that surround Hooke Park within a 15km radius. Although there are new woodlands that exist within that vicinity, ancient woodlands are the most ideal roosting and foraging areas for bats due to its mixed, old trees and more variety in insects.
28
15 km
10 km
5 km
Hooke Park
5 km
10 km
15 km
N
Ancient and Semi-Natural Woodland Ancient Replanted Woodland A radial map with Hooke Park at the centre, indicating 5km, 10km and 15 km distance and the ancient woodlands that surrounds Hooke Park.
Hooke Park
29
Bats in traditional buildings Section B
About Bats 1. Information on Bats
Section B
1.1 Bat Species in the UK
1.1.1 List of UK Bat Species
Bats in the UK
Why bats use buildings Common name
Scientific name
Status
Barbastelle
Barbastella barbastellus
Rare; threatened; UK BAP Priority Speci EU Priority Species
Bechstein’s bat
Myotis bechsteinii
Rare; threatened. UK B vulnerable species
Brandt’s bat
Myotis brandtii
Uncommon; not threatened.
Brown long-eared bat
Plecotus auritus
Threatened; UK BAP P Species.
Common pipistrelle
Pipistrellus pipistrellus
Frequent; not threaten
6
Daubenton’s bat
Myotis daubentonii
Frequent; not threaten
7
Greater horseshoe bat
Rhinolophus ferrumequinum
Rare; threatened; UK B Priority Species; EU Pr Species
8
Greater mouse-eared bat
Myotis myotis
Very rare; at one time considered extinct in B
9
Grey long-eared bat
Plecotus austriacus
Very rare
10
Leisler’s bat
Nyctalus leisleri
Occasionally found in and Wales; more frequ Ireland
11
Lesser horseshoe bat
Rhinolophus hipposideros
Occasional or frequen threatened; UK BAP P Species; EU Priority Sp
12
Nathusius’ pipistrelle
Pipistrellus nathusii
Rare
13
Natterer’s bat
Myotis nattereri
Not threatened
14
Noctule
Nyctalus noctula
Threatened; UK BAP P Species
15
Serotine
Eptesicus serotinus
Rare
Soprano pipistrelle
Pipistrellus pygmaeus
Threatened; UK BAP P Species
Whiskered bat
Myotis mystacinus
Not threatened
Bats are mammals and account for more than agives quarteryou of mammal species in the This section information about
bats UK. Currently, there are 17 known bat species in theand UK (as shown table on and their habits, tells youin the where you are1 the right). These 17 species include species inhabit small, local most bat likely to that come across batsareas in year buildings. round and bat species that migrate from UK across Europe.
A colony of bats will have several roost sites2 that they will use according to their needs 3 and the time of year. An absence of bats does not mean that the roost is no longer being 4 used. See Choosing a roost site, p 15. Identifying whether bats actually use a 5 building, and understanding the patterns of use, requires specialist knowledge. See Finding bats and their roosts, p 19.
The UK Biodiversity Action Plan (UK BAP) is part of an inter16 national framework to conserve and enhance biodiversity. Seven species of bat are on the UK 17 BAP’s priority list (of species and habitats) meaning that they are rare and/or in decline.
12 29128_Text.indd 12
30
* Includes mines, bridges, caves, tunnels, cellars and ice houses.
Section B Why bats use buildings
Distribution
Roost size
Summer roosts
Winter roosts
Foraging habitat
ies;
Southern half of England and Wales
1–50
Tree cavities and occasionally old buildings such as barns
Tree cavities and underground sites*
Ancient woodlands and pasture, parkland, hedgerows
BAP
Southern England
1–100
Tree cavities, especially old woodpecker holes
Tree cavities and underground sites*
Ancient woodlands
England, Wales and Ireland
30–200
Mainly roof voids in buildings
Underground sites*
Woodland and tree-lined water bodies
Throughout the UK and Republic of Ireland (RoI)
10–20 (can be up to 100)
Roof voids in older buildings, barns, churches and tree cavities; bat boxes
Tree cavities and underground sites*
Woodland, gardens and orchards
50–200
Outer parts of buildings (confined spaces such as soffits and under hanging tiles rather than roof voids)
In confined spaces in buildings
Woodland, gardens, parkland, hedgerows; around water bodies
Priority
ned Throughout the UK and RoI
ned
Throughout the UK and RoI
20–50 (can be up to 200)
Tree cavities; also tunnels and bridges
Tree cavities and underground sites*
Over water
BAP riority
South-west England and south-west Wales
50–200 (can be up to 600)
Mainly large roof voids of old buildings
Underground sites*
Parkland and woodland, steep-sided valleys
Britain
South coast of England; only one hibernation site known
Mainly large roof voids of old buildings
Underground sites*
Pasture and woodland
Southern England
10–20 (can be up to 50)
Buildings
Caves and tunnels; also probably uses trees and buildings
Parkland and woodland
England uent in
England, Wales and Ireland
20–100
Buildings, bat boxes
Buildings
Woodland and parkland
nt; Priority pecies
South-west England, Wales and RoI, spreading north and east
30–70 (can be up to 400)
Mainly large roof voids of old buildings
Underground sites*
Woodland and parkland
Throughout the UK during migration; resident in Northern Ireland
1–100
Buildings
Buildings
Woodland, especially near water bodies
Widespread in UK and RoI
20–100+
Old stone buildings and large, timbered barns; tree holes; bat boxes
Tree cavities, bat boxes and underground sites*
Woodland and parkland
England and Wales; absent from Ireland
15–50 (can be up to 100)
Tree cavities, occasionally buildings
Tree cavities
Woodland, pasture and lakes
Largely confined to counties south of Lincolnshire and Ceredigion but may be spreading north and west
15–30
Buildings
Buildings; rarely underground sites*
Woodland, pasture and lakes
Throughout the UK and RoI
50–1,000 (2,000 exceptional)
Buildings, bat boxes and trees
Buildings, bat boxes, and tree cavities
Widespread, especially near water bodies
Throughout the UK and RoI
30–200
Mainly roof voids of older houses
Underground sites*
Woodland, gardens, parkland, hedgerows; around water bodies
Priority
Priority
Bats in the UK
Bat Conservation Trust There are 18 known bat species in the UK, 17 of which breed here and account for more than a quarter of the mammal species in the UK.
13
6/3/09 00:37:45 29128_Text.indd 13
Source: The information shown in the table above is from a document called “Bats in Traditional Buildings” produced by English Heritage, The National Trust and Natual England in6/3/09 2009.00:37:46
About Bats
31
About Bats 1. Information on Bats
1.1 Bat Species in the UK
1.1.2 Distribution of Bat Species in Dorset
1
Barbastelle
6
Daubenton’s bat
2
Bechstein’s bat
7
Greater horseshoe bat
3
Brandt’s bat
8
Greater mouse-eared bat
4
Brown long-eared bat
9
Grey long-eared bat
5
Common pipistrelle
10
Leisler’s bat
32
11
Lesser horseshoe bat
16
Soprano pipistrelle
12
Nathusius’ pipistrelle
17
Whiskered bat
13
Natterer’s bat
14
Noctule
15
Serotine
Source: The distribution maps shown above is from a document provided by the Bat Conservation Trust website, data collected from Dorset Environmental Records Centre.
About Bats
33
About Bats 1. Information on Bats
1.1 Bat Species in the UK
1.1.3 Biology and Behavior
Bats are noctural mammals. They all use echolocation to navigate and hunt for food and they have incredible skills in flight. However, bat species differ in their shape, size and colour . They also differ in their diet, echolocation and life span. All UK bat species only eat night-flying insect, contrary to tropical bats that also eat many other foods such as fruit, flowers, frogs, and more. Bats use echolocation to navigate and find food in the dark. To echolocate, bats send out sound waves from the mouth or nose. When the sound waves hit an object they produce echoes. The echo bounces off the object and returns to the bats’ ears. Therefore, the hearing is particularly sensitive. The diagram on the right is widely used in the UK to identify bats by their physical characteristics. The table in the following page provides more detailed information on each particular bat species’ dimensions weight, colour, diet, echolcation frequency, emergence from roost, flight behavior and life span.
34
“A Guide to British Bats” leaflet published by Field Studies Council (FSC) to aid the public in bat identification through observations of physical characteristics.
35
About Bats 1. Information on Bats
1.1 Bat Species in the UK
1.1.3 Biology and Behavior
Common name
Dimensions
Weight
Colour
Diet
1
Barbastelle
Head & body length: 40mm - 52mm Wingspan: 230mm - 285m5
6g - 13g
Fur dark, lighter tips on back. Skin surfaces black or brown.
Mainly small moths, some flies and beetles.
2
Bechstein’s bat
Head & body length: 43mm - 53mm Wingspan: 250mm - 300mm
7g - 13g
Pale to reddish brown fur, greyish underneath. Pink face.
Dung flies, grasshoppers and nut weevils, moths and flies.
3
Brandt’s bat
Head & body length: 38mm- 50mm Wingspan: 230mm - 285mm
4.5g - 9.5g
Fur dark grey or brown, golden tips on back, greyish underneath; Face and base of ears often pinkish.
Moths, other small insects and spiders.
4
Brown long-eared
Head & body length: 37mm - 52mm Wingspan: 230mm - 285mm
6g - 12g
Adults have light brown fur, pale underneath; juveniles greyish.
Moths, beetles, flies, earwigs, and spiders
5
Common pipistrelle
Head & body length: 35mm - 45mm Wingspan: 200mm - 235mm
3g - 8g
Medium to dark brown. Face and around the eyes are usually dark.
Small flies, aquatic midges and mosquitoes.
6
Daubenton’s bat
Head & body length: 45mm - 55mm Wingspan: 240mm - 275mm
7g - 12g
Fur red brown, pale underneath; Pinkish face, bare around the eyes.
Small flies, (especially chironomid midges), caddisflies and mayflies.
7
Greater horseshoe bat
Head & body length: 57mm - 71mm Wingspan: 350mm - 400mm
17g - 34g
Adults buff borwn, juveniles greyish.
Chafers, dung beetles, noctuid moths, craneflies and caddis flies.
8
Greater mouse-eared bat
Head & body length: 65mm - 80mm Wingspan: 365mm - 450mm
24g - 40g
Dorsal fur is a sandy colour which contrasts strongly with the white fur underneath.
Larger insects (such as moths, cockchafrers, crickets, beetles, spiders)
9
Grey long-eared bat
Head & body length: 41mm - 58mm Wingspan: 255mm - 300mm
7g - 12g
Larger and greyer than the brown long eared bat. Face often darker with a blackish mask.
Moths, Diptera (mainly Tipulids- crane flies), small beetles.
10
Leisler’s bat
Head & body length: 50mm - 70mm Wingspan: 260mm - 320mm
12g - 20g
Fur golden-tipped or reddish brown, darker at base.
Flies, moths, caddis flies, beetles.
11
Lesser horseshoe bat
Head & body length: 35mm - 45mm Wingspan: 200mm - 250mm
5g - 9g
Adults pinky buff-brown; juveniles greyish (until 1 year old).
Flies (usually midges), small moths, caddis flies, lacewings, beetles, small wasps and spiders.
12
Nathusius’ pipistrelle
Head & body length: 46mm - 55mm Wingspan: 228mm - 250mm
6g - 16g
Fur reddish brown; occasionally with frosted tips on the belly. The ears, membranes and face are usually dark.
Medium sized insects (such as aquatic flies, midges, mosquitoes and caddis flies).
13
Natterer’s bat
Head & body length: 40mm - 50mm Wingspan: 245mm - 300mm
7g - 12g
Fur light buff brown or black, white underneath. Bare pink face.
Flies (mainly midges), small moths, caddis flies, lacewings, beetles, small wasps, spiders.
14
Noctule
Head & body length: 37mm - 48mm Wingspan: 320mm - 400mm
18g - 40g
Adults sleek chocolate brown, juveniles and some females dull chocolate brown.
Moths, beetles (mainly chafer and dung beeltes), mayflies and winged ants.
15
Serotine
Head & body length: 58mm - 80mm Wingspan: 320mm - 380mm
15g - 35g
Fur dark brown above, pale underneath; face and ears black.
Flies and moths, chafers and dung beetles
16
Soprano pipistrelle
Head & body length: 35mm - 45mm Wingspan: 320mm - 400mm
3g - 8g
Medium to dark brown. Face and around the eyes usually pink on colour.
Small flies, particularly midges and mosquitoes that are associated with water.
17
Whiskered bat
Head & body length: 35mm - 48mm Wingspan: 210mm - 240mm
4g - 8g
Fur dark grey or brown; golden tips on back, greyish underneath.
Moths, other small insects and spiders,.
36
Echolocation
Emergence (after sunset)
Flight Pattern
Flight Picture
32kHz
30mins - 60mins
Fast, purposeful flight in vegetation and along habitat edges.
Up to 23 years.
50kHz
30mins
Flies at different heights in vegetation with a slow, fluttering flight which is very agile even in confined spaces.
Up to 21 years.
33kHz - 50kHz; loudest at 45kHz
30mins
Fast and straight flight at head height along habitat edges. More associated with woodland than Whiskered bats.
Up to 40 years.
25kHz - 50kHz; peak at 35kHz
45mins - 65mins
Slow, fluttering, agile flight in vegetation with occasional hovering pauses.
Up to 30 years.
45kHz - 70kHz
20mins - 30mins; occasionally before sunset.
Fast, erratic flight at head height often along habitat edges.
4 - 5 years.
35kHz - 85 kHz; loudest at 45kHz - 50kHz
40mins - 50mins
Fast, stright flight most often low over smooth water and sometimes along habitat edges.
Up to 22 years.
82kHz
40mins - 50mins
Slow, fluttering flight with short glides close to the ground alonog habitat edges or in vegetation.
Up to 30 years.
22kHz - 86kHz
No information on emergence.
No information on flight pattern.
29.8kHz - 62.5kHz
45mins - 65mins
Slow, fluttering, agile flight in vegetation with occasional hovering pauses.
5 - 9 years.
15kHz - 45kHz
10mins - 15mins; occasionally before sunset.
Fast, straight flight above trees in open habitats. Dives less steeply when hunting than the Noctule bat.
8 years.
110kHz
40mins - 50mins
Fairly fast and skilful flight close to the ground along habitat edges or in vegetation.
4 years.
36kHz - 40kHz
20mins - 30mins
Fast, erratic flight at head height often along habitat edges. Not as manouvarable as other pipistrelle bats in vegetation.
Up to 16 years.
35kHz - 80kHz; peak at 50kHz
40mins - 60mins
Fast and agile flight at head height in habitat edges and sometimes low over water.
7 years.
20kHz - 45kHz; peak at 35kHz
5mins - 10mins; occasionally before sunset.
Fast, straight flight above trees in open habitats. Dives steeply when hunting.
4 - 5 years.
15kHz - 65kHz; peak at 25kHz - 30kHz
20mins - 25mins; occasionally before sunset.
Relatively slow flight often above roof height. Flies in loops in open areas and much closer to vegetation than notcule bats.
Up to 19 years.
55kHz - 80kHz
20mins - 30mins; occasionally before sunset.
Fast, erratic flight at head height often along habitat edges.
4 -5 years.
32kHz - 89kHz; loudest at 45kHz
30mins
Fast and straight flight at head height along habitat edges.
4 years.
No information on flight picture.
Life Span
Up to 18 years.
Source: The information shown in the table above is from a series of documents about specific bat species provided by the Bat Conservation Trust website and the Field Studies Council.
About Bats
37
About Bats 1. Information on Bats
1.2 Life of a Bat in One Year
Jan
Feb
Mar
Apr
May
Jun
Hibernating. Using stored fat as fuel. Heart beats six times during hiberation.
Hibernating. Little fat left.
Signs of limited activity. Small numbers feed at night. Food to top up fat reserves.
Active and hungry. Become torpid again when cold.
Fully active. Females search for suitable nursery sites. Separation of male and female reoosts. Females pregnant for six to nine weeks.
The young are born.
Transition Transition Winter: Hibernation Roost Winter: Hibernation Roost
38
Maternity Roost Maternity/Sa
Jul
Aug
Sep
Oct
Nov
Dec
Mothers suckle their young almost full size; others still very small.
Females desert nusery sites and seek males. Juveniles begin catching insects.
Mating takes place. Fat begins to build up ready for winter. Females store sperm for the Spring.
More mating. Seeking suitable hibernation sites. Periods of tarpor.
More mating. Seeking suitable hibernation sites. Periods of torpor.
Hibernation.
nalRoost Roost nal Winter: Roost Winter:Hibernation Hibernation Roost
/ Satellite atellite RoostRoost Mating Roost Mating Roost DayDay/Night / Night Roost Roost
The diagram above indicates the life of a bat in one year from their level of activity to their roosting preferences.
About Bats
39
About Bats 1. Information on Bats
1.3 Importance of Bats
As described by the Bat Conservation Trust, there are four main key points as to
then excrete the seeds far away from the original tree. These seeds drop to the
why bats play an important role in many environments:
ground in their own ready-made fertiliser, which helps them germinate and grow. Because bats help pollinate and disperse seeds, they can even play an important
Bats are indicators of biodiversity
part in helping regrowth after forest clearance.
“Bats are a vital part of our native wildlife, accounting for almost a third of all mammal species in the UK and occupy a wide range of habitats, such as wetlands,
Even small bats can have an important part to play in seed dispersal, as recent re-
woodlands, farmland, as well as urban areas. They can tell us a lot about the state
search on neotropical bats in Central and South American forests suggests. These
of the environment, as they are top predators of common nocturnal insects and are
forests have been cleared and fragmented, while hunting and habitat loss has
sensitive to changes in land use practices. The pressures they face - such as land-
wiped out some populations of large bodied animals like deer and macaws. It had
scape change, agricultural intensification, development, and habitat fragmentation
been thought that without these animals, many large-seeded plants would have no
are also relevant to many other wildlife species, making them excellent indicators
way of dispersing their seeds. However, researchers looked at seed dispersal both
for the wider health of the UK’s wildlife.”
at random through the forest and underneath the tents of tentmaker bats. These studies have shown that the number of large seeds under the tents is higher than
Bats are pollinators
would occur at random, so tentmaker bats might be playing a crucial role in the
“Many people are unaware that over 500 plant species rely on bats to pollinate
dispersal of up to 44-65 large seeded plant species throughout the forest.
their flowers, including species of mango, banana, durian, guava and agave (used to make tequila). So, next time you drink some tequila or eat a mango, say thanks
Some plants depend partly or wholly on bats to pollinate their flowers or spread
to the bats! The pollination of plants by bats is called chiropterophily.
their seeds, while other bats also help control pests by eating insects. In the UK, some bats are ‘indicator species’, because changes to these bat populations can
Plants pollinated by bats often have pale nocturnal flowers (in contrast, bees are
indicate changes in aspects of biodiversity. Bats might suffer when there are
mostly attracted to bright, daytime flowers). These flowers are often large and bell
problems with insect populations (because our bats feed on insects) or when
shaped, and some bats have evolved specifically to reach the nectar at the bottom
habitats are destroyed or poorly managed (for example, some bats only live in large
of them. The tube-lipped nectar bat of Ecuador and the banana bat that lives only
woodlands).”
on the Pacific coast of Mexico both have extraordinarily long tongues for this exact reason. The tube-lipped nectar bat’s tongue is more than one and a half times the length of its body!” Bats are pest control “While some people think bats are pests, some bats are actually pest controllers eating thousands of insects every night. UK bats won’t bite you or suck your blood – but they will help clear the air of bloodsucking mosquitoes! All bats in the UK are insectivores – they only eat insects. Insect-eating bats are great for keeping bugs away from crops, as well as the places where the bats roost. The Brazilian free-tailed bat has been recognised as an important “pest management service” in cotton farming. Because bats eat so many insects in some regions, they can also reduce the need for pesticide sprays. While bats can provide a valuable service for agriculture, some agricultural practices can have a detrimental impact on bats. Increased use of pesticides may mean that bats go hungry from the lack of insect prey.” Bats are seed dispersers and reforesters “Like birds, some bats play a critical role in spreading the seeds of trees and other plants. Some tropical fruit bats carry seeds inside them as they digest the fruit,
40
A photo of a Daubenton in flight catching an insect. Photograph taken by Paul Colley in 2018.
About Bats
41
About Bats 1. Information on Bats
1.4 Bats and the Law
All UK bat species are protected wildlife species by both UK and EU law due to a significant decline over the last few decades. This drop in population is due to a few reasosn: the loss of roosting sites, foraging habitats, and commuting flight lines, and due to a significant decrease in the insect populations. Therefore, bats and their roosting places (whether bats are present or not) have become protected by two major pieces of wildlife legislation:’ The Wildlife and Countryside Act 1981 (WCA)’ and ‘The Conservation of Habitats and Species Regulations (2017) (as amended)’. The table on the right summarizes the two wildlife legislations. The table on the following page shows the legal and conservation status of each UK bat species. In short, it is illegal to disturb, harm or obstruct bats or bat roosts. This is an important piece of information considering bats, over time, have found manmade architecture are suitable sites for roosting. These two legislations applies to everybody but in particular to builders, roofers, property owners/householders (who have bat roosts in their property), woodland owners, arboriculturalists and foresters, planning officers and building surveyors, architects, demolition companies and propery developers.
42
1 The Wildlife and Countryside Act 1981 (WCA)
2 The Conservation Natural Habitats and Species Regulations (2017) (as amended)
It is illegal to:
It is illegal to:
• intentionally or recklessly disturb a bat while it is occupying a structure or place which it uses for shelter or protection (roost)
• deliberately capture, injure or kill a bat
• intentionally or recklessly obstruct access to any structure or place which it uses for shelter or protection • sell, offer for sale or possess for the purpose of sale any bat or part of a bat or advertise sales or purchases of bats
• deliberately disturb bats in a way that affects their ability to survive, breed, hibernate or migrate, or signifi cantly affects their local distribution orabundance • damage or destroy a breeding site or resting place of a bat [note that this does not have to be deliberate] • possess or control, transport, sell or exchange, or offer for sale or exchange a live or dead bat or any part of a bat.
Source: Bats and the Law, Bat Conservation Trust Website.
About Bats
43
About Bats 1. Information on Bats
1.4 Bats and the Law
Common name
Bern Convention Appendix II
1
Barbastelle
•
2
Bechstein’s bat
3
Bonn Convention Appendix II
WCA
Habitats Directive Annex IV
Habitats Directive Annex II
Habs Regs 1994 (as am.) Scotland
•
•
•
•
•
•
Brandt’s bat
•
•
•
•
•
4
Brown long-eared
•
•
•
•
•
5
Common pipistrelle
•
•
•
•
•
6
Daubenton’s bat
•
•
•
•
•
7
Greater horseshoe bat
•
•
•
•
8
Greater mouse-eared bat
•
•
•
•
•
9
Grey long-eared bat
•
•
•
•
•
10
Leisler’s bat
•
•
•
•
•
11
Lesser horseshoe bat
•
•
•
•
12
Nathusius’ pipistrelle
•
•
•
•
•
13
Natterer’s bat
•
•
•
•
•
14
Noctule
•
•
•
•
•
15
Serotine
•
•
•
•
•
16
Soprano pipistrelle
•
•
•
•
17
Whiskered bat
•
•
•
•
44
•
• •
•
•
•
• •
•
•
• •
Conservation of Habs & Sp. Regs 2010
•
Conservation Regs (N Ireland) 1995
CROW Act 2000
NERC Act 2006
Wild Mammals Protection Act
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
UK BAP Priority Species
IUCN Red List
EUROBATS Agreement
•
Near threatened
•
•
Near threatened
•
Least concern
•
Near threatened
•
•
Least concern
•
•
•
Least concern
•
•
•
•
Least concern
•
•
•
•
•
Least concern
•
•
•
•
•
•
Least concern
•
•
•
•
•
•
Least concern
•
•
•
•
•
•
Least concern
•
•
•
•
•
•
Least concern
•
•
•
•
•
•
Least concern
•
•
•
•
•
•
Least concern
•
•
•
•
•
•
Least concern
•
•
•
•
•
•
Least concern
•
•
•
•
•
•
Least concern
•
•
•
•
•
The table above shows the legal and conservation status of UK bat species. Information from the Bat Conservation Trust.
About Bats
45
About Bats 1. Information on Bats
1.5 Bats and Architecture
RIBA Plan of Work 2020 Template
According to the RIBA Plan of Work 2020, a project will go through seven work stages: 0 - Strategic Definition, 1 - Preperation and Briefing, 2 - Concept Design, 3 - Spatial Coordination, 4 - Technical Design, 5 - Maunufacturing and Construction, 6- Handover, and 7 - Use.
RIBA One of the core tasks in Stage 1 is to source site information and include site ofareWork surveys. This also entails ecological consultancy and batPlan surveys that required 2020 to be conducted for any conversion, modification, demolition or removal work of a building.
Stage Boundaries:
Stages 0-4 will generally beliscence undertaken one after Once the surveys have been conducted, it may still require in order for an the other. architectural project to continue. The scale and type of building works or activity Stages 4 and 5 will overlap may require a liscence that takes two months for approval.in the Project Programme for most projects. Stage 5 commences when the contractor takes possession of the site and finishes at Practical Completion. Stage 6 starts with the handover of the building to the client immediately after Practical Completion and finishes at the end of the Defects Liability Period. Stage 7 starts concurrently with Stage 6 and lasts for the life of the building.
Planning Note: Planning Applications are generally submitted at the end of Stage 3 and should only be submitted earlier when the threshold of information required has been met. If a Planning Application is made during Stage 3, a midstage gateway should be determined and it should be clear to the project team which tasks and deliverables will be required. See Overview guidance.
Procurement: The RIBA Plan of Work is procurement neutral – See Overview guidance for a detailed description of how each stage might be adjusted to accommodate the requirements of the Procurement Strategy. ER
Employer’s Requirements
CP
Contractor’s Proposals
The RIBA Plan of Work organises the process of briefing, designing, delivering, maintaining, operating and using a building into eight stages. It is a framework for all disciplines on construction projects and should be used solely as guidance for the preparation of detailed professional services and building contracts.
0
1
2
Strategic Definition
Preparation and Briefing
Co De
Stage Outcome
The best means of achieving the Client Requirements confirmed
at the end of the stage
Projects span fro
If the outcome determines that a building is the best means of achieving the Client Requirements, the client proceeds to Stage 1
Core Tasks
Prepare Client Requirements
during the stage
Develop Business Case for feasible options including review of Project Risks and Project Budget
Project Strategies might include: – Conservation (if applicable) – Cost – Fire Safety – Health and Safety – Inclusive Design – Planning – Plan for Use – Procurement – Sustainability See RIBA Plan of Work 2020 Overview for detailed guidance on Project Strategies
Core Statutory Processes
Ratify option that best delivers Client Requirements
Arch appr align
Prepare Project Brief including Project Outcomes and Sustainability Outcomes, Quality Aspirations and Spatial Requirements
Prep Con Stra requ Cos and
Undertake Feasibility Studies Agree Project Budget
Agre Dero
Source Site Information including Site Surveys
Undertake Site Appraisals
Prepare Project Programme
Und with Stak
Prepare Project Execution Plan
Prep Prog
No design team required for Stages 0 and 1. Client advisers may be appointed to the client team to provide strategic advice and design thinking before Stage 2 commences.
Strategic appraisal of Planning considerations
Planning Building Regulations Health and Safety (CDM)
Source pre-application Planning Advice
Obta Plan
Initiate collation of health and safety Pre-construction Information
Agre Reg
Opt Plan
Traditional
Design & Build 1 Stage Design & Build 2 Stage
Appoint client team
Management Contract Construction Management Contractor-led
Information Exchanges
at the end of the stage
Ecological consultations and bat Appoint team surveys are required fordesign conversion, modification, demolition or removal of buildings. Most of these consultations and surveys take ER place in May - August).
Client Requirements
Project Brief
Proj
Business Case
Feasibility Studies
Sign
Site Information
Proj
Project Budget
Outl
Project Programme
Cos
Procurement Strategy
46
The Stag resp Con
Review Feedback from previous projects
during the stage:
Procurement Route
Project Brief approved by the client and confirmed that it can be accommodated on the site
Responsibility Matrix Information Requirements Core RIBA Plan of Work terms are defined in the RIBA Plan of Work 2020 Overview glossary and set in Bold Type.
2
oncept esign
3
4
5
6
7
Spatial Coordination
Technical Design
Manufacturing and Construction Handover
Use
om Stage 1 to Stage 6; the outcome of Stage 0 may be the decision to initiate a project and Stage 7 covers the ongoing use of the building.
hitectural Concept roved by the client and ned to the Project Brief
Architectural and engineering information Spatially Coordinated
brief remains “live” during ge 2 and is derogated in ponse to the Architectural ncept
All design information required to manufacture and construct the project completed Stage 4 will overlap with Stage 5 on most projects
pare Architectural ncept incorporating ategic Engineering uirements and aligned to st Plan, Project Strategies Outline Specification
ee Project Brief ogations
dertake Design Reviews h client and Project keholders
Undertake Design Studies, Engineering Analysis and Cost Exercises to test Architectural Concept resulting in Spatially Coordinated design aligned to updated Cost Plan, Project Strategies and Outline Specification Initiate Change Control Procedures Prepare stage Design Programme
pare stage Design gramme
Develop architectural and engineering technical design Prepare and coordinate design team Building Systems information Prepare and integrate specialist subcontractor Building Systems information Prepare stage Design Programme
Manufacturing, construction and Commissioning completed
Manufacture Building Systems and construct building
Inspect Construction Quality
Rectify defects
Resolve Site Queries as required
Complete initial Aftercare tasks including light touch Post Occupancy Evaluation
Undertake Commissioning of building
Building handover tasks bridge Stages 5 and 6 as set out in the Plan for Use Strategy
Submit Building Regulations Application
Carry out Construction Phase Plan
ee route to Building gulations compliance
Prepare and submit Planning Application
Discharge precommencement Planning Conditions
Comply with Planning Conditions related to construction
Implement Facilities Management and Asset Management Undertake Post Occupancy Evaluation of building performance in use Verify Project Outcomes including Sustainability Outcomes
Comply with Planning Conditions as required
Adaptation of a building (at the end of its useful life) triggers a new Stage 0
Comply with Planning Conditions as required
Prepare Construction Phase Plan Submit form F10 to HSE if applicable Tender ER CP
Appoint contractor
Pre-contract services agreement
CP
Appoint contractor
Preferred bidder
CP
Appoint contractor
Appoint contractor
Appoint Facilities Management and Asset Management teams, and strategic advisers as needed
Appoint contractor
ject Brief Derogations
Signed off Stage Report
Manufacturing Information
ned off Stage Report
Project Strategies
Construction Information
ject Strategies
Updated Outline Specification
Final Specifications
tline Specification
st Plan
Undertake review of Project Performance Undertake seasonal Commissioning
Review design against Building Regulations
ER
Hand over building in line with Plan for Use Strategy
Monitor progress against Construction Programme
tain pre-application nning Advice
See Planning Note for guidance on submitting a Planning Application earlier than at end of Stage 3
Stage 7 starts concurrently with Stage 6 and lasts for the life of the building
There is no design work in Stage 5 other than responding to Site Queries
Finalise Site Logistics
Building used, operated and maintained efficiently
Prepare Building Manual Specialist subcontractor designs are prepared and reviewed during Stage 4
tion: submit outline nning Application
Building handed over, Aftercare initiated and Building Contract concluded
Updated Cost Plan Planning Application
Residual Project Strategies Building Regulations Application
Building Manual including Health and Safety File and Fire Safety Information Practical Completion certificate including Defects List Asset Information If Verified Construction Information is required, verification tasks must be defined
Further guidance and detailed stage descriptions are included in the RIBA Plan of Work 2020 Overview.
Feedback on Project Performance
Feedback from Post Occupancy Evaluation
Final Certificate
Updated Building Manual including Health and Feedback from light touch Safety File and Fire Safety PostThe Occupancy Evaluation table above shows the RIBAInformation Work of Plan illustrating in as2020, necessary detail the seven work stages. The outline box indicates the stage in which site surveys (including ecological surveys) are required.
About Bats
47
© RIBA 2020
About Bats 1. Information on Bats
1.5 Bats and Architecture
RIBA Plan of Work 2020 Template
0
1
2
RIBA Plan of Work 2020
The RIBA Plan of Work organises the process of briefing, designing, delivering, maintaining, operating and using a building into eight stages. It is a framework for all disciplines on construction projects and should be used solely as guidance for the preparation of detailed professional services and building contracts.
Strategic Definition
Preparation and Briefing
Co De
Stage Boundaries:
Stage Outcome
The best means of achieving the Client Requirements confirmed
Stages 0-4 will generally be undertaken one after the other. Stages 4 and 5 will overlap in the Project Programme for most projects. Stage 5 commences when the contractor takes possession of the site and finishes at Practical Completion. Stage 6 starts with the handover of the building to the client immediately after Practical Completion and finishes at the end of the Defects Liability Period. Stage 7 starts concurrently with Stage 6 and lasts for the life of the building.
Planning Note: Planning Applications are generally submitted at the end of Stage 3 and should only be submitted earlier when the threshold of information required has been met. If a Planning Application is made during Stage 3, a midstage gateway should be determined and it should be clear to the project team which tasks and deliverables will be required. See Overview guidance.
Procurement: The RIBA Plan of Work is procurement neutral – See Overview guidance for a detailed description of how each stage might be adjusted to accommodate the requirements of the Procurement Strategy. ER
Employer’s Requirements
CP
Contractor’s Proposals
at the end of the stage
Projects span fro
If the outcome determines that a building is the best means of achieving the Client Requirements, the client proceeds to Stage 1
Core Tasks
Prepare Client Requirements
during the stage
Develop Business Case for feasible options including review of Project Risks and Project Budget
Project Strategies might include: – Conservation (if applicable) – Cost – Fire Safety – Health and Safety – Inclusive Design – Planning – Plan for Use – Procurement – Sustainability See RIBA Plan of Work 2020 Overview for detailed guidance on Project Strategies
Core Statutory Processes
Ratify option that best delivers Client Requirements
Arch appr align
Prepare Project Brief including Project Outcomes and Sustainability Outcomes, Quality Aspirations and Spatial Requirements
Prep Con Stra requ Cos and
Undertake Feasibility Studies Agree Project Budget
Agre Dero
Source Site Information including Site Surveys
Undertake Site Appraisals
Prepare Project Programme
Und with Stak
Prepare Project Execution Plan
Prep Prog
No design team required for Stages 0 and 1. Client advisers may be appointed to the client team to provide strategic advice and design thinking before Stage 2 commences.
Strategic appraisal of Planning considerations
Planning Building Regulations Health and Safety (CDM)
Source pre-application Planning Advice
Obta Plan
Initiate collation of health and safety Pre-construction Information
Agre Reg
Opt Plan
Traditional
Design & Build 1 Stage Design & Build 2 Stage
Appoint client team
Appoint design team
Management Contract Construction Management Contractor-led
Information Exchanges
at the end of the stage
ER
Client Requirements
Project Brief
Proj
Business Case
Feasibility Studies
Sign
Site Information
Proj
Project Budget
Outl
Project Programme
Cos
Procurement Strategy
48
The Stag resp Con
Review Feedback from previous projects
during the stage:
Procurement Route
Project Brief approved by the client and confirmed that it can be accommodated on the site
Responsibility Matrix Information Requirements Core RIBA Plan of Work terms are defined in the RIBA Plan of Work 2020 Overview glossary and set in Bold Type.
2
oncept esign
3
4
5
6
7
Spatial Coordination
Technical Design
Manufacturing and Construction Handover
Use
om Stage 1 to Stage 6; the outcome of Stage 0 may be the decision to initiate a project and Stage 7 covers the ongoing use of the building.
hitectural Concept roved by the client and ned to the Project Brief
Architectural and engineering information Spatially Coordinated
brief remains “live” during ge 2 and is derogated in ponse to the Architectural ncept
Photograph 1 Frontage of 1-2 Lincolns Inn’s Field.
pare Architectural ncept incorporating ategic Engineering uirements and aligned to st Plan, Project Strategies Outline Specification
ee Project Brief ogations
dertake Design Reviews h client and Project keholders
Undertake Design Studies, Engineering Analysis and Cost Exercises to test Architectural Concept resultingPhotograph in Spatially 2 Coordinated design aligned Slate tile pitched roof and chimney breasts. to updated Cost Plan, Project Strategies and Outline Specification Initiate Change Control Procedures Photograph 3 Prepare stage Design Programme
Underground vaults at the basement level. Gaps were evident in the concrete above the wooden doors.
pare stage Design gramme
All design information required to manufacture and construct the project completed
Manufacturing, construction and Commissioning completed
There is Photograph 4 no design work in Stage 5 than responding to Site Stage 4 will overlap with Stage 5 above theother Loose bricks window on the northern elevation which may Queries on most projects provide roosting opportunities for
Develop architectural and engineering technical design
Finalise Site Logistics
Manufacture Building Systems and construct Prepare and coordinate Photograph 5 building design team Building and broken slate roof tiles Systems information Missingproviding potential roosting opportunities for crevice-dwelling Monitor progress against bat species. Construction Programme Prepare and integrate specialist subcontractor Inspect Construction Quality Building Systems Resolve Site Queries as information required Photograph 6 Prepare stage Design Missing brick at the base of the Undertake Commissioning Programme chimney providing potential roosting opportunities for crevicebuilding dwellingof bat species.
Submit Building Regulations 23 Application
Carry out Construction 23 Phase Plan
ee route to Building gulations compliance
Prepare and submit Planning Application
Discharge precommencement Planning Conditions
Comply with Planning Conditions related to construction
The Ecology Consultancy 1-2 Lincolns Inn Field, London /Preliminary Roost Assessment / David Chipperfield Architects
Stage 7 starts concurrently with Stage 6 and lasts for the life of the building
Implement Facilities Management and Asset Management
Photograph 9
View inside roof void of 1 Lincolns Inn Fields. The loft space was lined with bitumen felt which was lifted in places, providing potential roosting opportunities for crevice-dwelling bat species.
Comply with Planning 24 Conditions as required
The Ecology Consultancy 1-2 Lincolns Inn Field, London /Preliminary Roost Assessment / David Chipperfield Architects
24
Adaptation of a building (at the end of its useful life) triggers a new Stage 0
Comply with Planning Conditions as required
The Ecology Consultancy 1-2 Lincolns Inn Field, London /Preliminary Roost Assessment / David Chipperfield Architects
25
Prepare Construction Phase Plan Submit form F10 to HSE if applicable Tender ER CP
Appoint contractor
Pre-contract services agreement
CP
Appoint contractor
Preferred bidder
CP
Appoint contractor
Appoint contractor
Appoint Facilities Management and Asset Management teams, and strategic advisers as needed
Appoint contractor
ject Brief Derogations
Signed off Stage Report
Manufacturing Information
ned off Stage Report
Project Strategies
Construction Information
ject Strategies
Updated Outline Specification
Final Specifications
tline Specification
st Plan
Building used, operated and maintained efficiently
Undertake review of Project Performance Undertake Post Occupancy Photograph 8 Evaluation of building View inside roof void of 1 Lincolns Undertake seasonal Inn Fields with king post roof formation. performance in use Commissioning Verify Project Outcomes Rectify defects including Sustainability Complete initial Aftercare Outcomes tasks including light touch Post Occupancy Evaluation
Building handover tasks bridge Stages 5 and 6 as set out in the Plan for Use Strategy
Review design against Building Regulations
ER
Hand over building in line with Plan for Use Strategy
Prepare Building Manual
tain pre-application nning Advice
See Planning Note for guidance on submitting a Planning Application earlier than at end of Stage 3
Photograph 7 Slipped ridge tile on western elevation of 1 Lincolns Inn Fields providing potential access for bats into the roof void.
crevice-dwelling species.
Specialist subcontractor designs are prepared and reviewed during Stage 4
tion: submit outline nning Application
Building handed over, Aftercare initiated and Building Contract concluded
Updated Cost Plan Planning Application
Residual Project Strategies Building Regulations Application
Building Manual including Health and Safety File and Fire Safety Information Practical Completion certificate including Defects List Asset Information If Verified Construction Information is required, verification tasks must be defined
Further guidance and detailed stage descriptions are included in the RIBA Plan of Work 2020 Overview.
Feedback on Project Performance
Feedback from Post Occupancy Evaluation
Final Certificate
Updated Building Manual including Health and Feedback from light touch Safety File and Fire Safety Post Occupancy Evaluation The top table above shows the RIBAInformation Work of Plan illustrating in as2020, necessary detail the seven work stages. The seven pages below is an example of a bat survey, conducted on site in London by The Ecology Consultancy.
About Bats
49
© RIBA 2020
Bats in traditional buildings Section B
About Bats 2. Bats in Hooke Park
Section B
2.1 Bats Species of Hooke Park
Bats in the UK
Why bats use buildings Common name
Scientific name
Status
Barbastelle
Barbastella barbastellus
Rare; threatened; UK BAP Priority Speci EU Priority Species
Bechstein’s bat
Myotis bechsteinii
Rare; threatened. UK B vulnerable species
Brandt’s bat
Myotis brandtii
Uncommon; not threatened.
Brown long-eared bat
Plecotus auritus
Threatened; UK BAP P Species.
Common pipistrelle
Pipistrellus pipistrellus
Frequent; not threaten
6
Daubenton’s bat
Myotis daubentonii
Frequent; not threaten
7
Greater horseshoe bat
Rhinolophus ferrumequinum
Rare; threatened; UK B Priority Species; EU Pr Species
8
Greater mouse-eared bat
Myotis myotis
Very rare; at one time considered extinct in B
9
Grey long-eared bat
Plecotus austriacus
Very rare
10
Leisler’s bat
Nyctalus leisleri
Occasionally found in and Wales; more frequ Ireland
11
Lesser horseshoe bat
Rhinolophus hipposideros
Occasional or frequen threatened; UK BAP P Species; EU Priority Sp
12
Nathusius’ pipistrelle
Pipistrellus nathusii
Rare
13
Natterer’s bat
Myotis nattereri
Not threatened
14
Noctule
Nyctalus noctula
Threatened; UK BAP P Species
15
Serotine
Eptesicus serotinus
Rare
Soprano pipistrelle
Pipistrellus pygmaeus
Threatened; UK BAP P Species
Whiskered bat
Myotis mystacinus
Not threatened
According to the Stephen Hales has conducted monitoring in Hookeabout Park Thiswhosection givesbatyou information
bats a handful of times, he was able to detect speciesand of batstells that exist Hooke and theirtwo habits, youwithin where you are1 Park’s woodlands. He identified them as the to Serotine bat across and one ofbats the pipistmost likely come in buildings. relle species. However, which specific pipistrelle species (common, nathusius or soprano pipistrelle) is yet to A be confirmed. bat speices were identified a colony ofThebats will have severalwith roost
sites2 bat detector by Stephen Hales. Each bat species have according their own unique that they will use to frequency their needs 3 range, which helps bat experts or researchers the specific bat species. and the timeidentify of year. An absence of bats does not mean that the roost is no longer being 4 used. See Choosing a roost site, p 15. Identifying whether bats actually use a 5 building, and understanding the patterns of use, requires specialist knowledge. See Finding bats and their roosts, p 19.
The UK Biodiversity Action Plan (UK BAP) is part of an inter16 national framework to conserve and enhance biodiversity. Seven species of bat are on the UK 17 BAP’s priority list (of species and habitats) meaning that they are rare and/or in decline.
12 29128_Text.indd 12
50
* Includes mines, bridges, caves, tunnels, cellars and ice houses.
Section B Why bats use buildings
Distribution
Roost size
Summer roosts
Winter roosts
Foraging habitat
ies;
Southern half of England and Wales
1–50
Tree cavities and occasionally old buildings such as barns
Tree cavities and underground sites*
Ancient woodlands and pasture, parkland, hedgerows
BAP
Southern England
1–100
Tree cavities, especially old woodpecker holes
Tree cavities and underground sites*
Ancient woodlands
England, Wales and Ireland
30–200
Mainly roof voids in buildings
Underground sites*
Woodland and tree-lined water bodies
Throughout the UK and Republic of Ireland (RoI)
10–20 (can be up to 100)
Roof voids in older buildings, barns, churches and tree cavities; bat boxes
Tree cavities and underground sites*
Woodland, gardens and orchards
50–200
Outer parts of buildings (confined spaces such as soffits and under hanging tiles rather than roof voids)
In confined spaces in buildings
Woodland, gardens, parkland, hedgerows; around water bodies
Priority
ned Throughout the UK and RoI
ned
Throughout the UK and RoI
20–50 (can be up to 200)
Tree cavities; also tunnels and bridges
Tree cavities and underground sites*
Over water
BAP riority
South-west England and south-west Wales
50–200 (can be up to 600)
Mainly large roof voids of old buildings
Underground sites*
Parkland and woodland, steep-sided valleys
Britain
South coast of England; only one hibernation site known
Mainly large roof voids of old buildings
Underground sites*
Pasture and woodland
Southern England
10–20 (can be up to 50)
Buildings
Caves and tunnels; also probably uses trees and buildings
Parkland and woodland
England uent in
England, Wales and Ireland
20–100
Buildings, bat boxes
Buildings
Woodland and parkland
nt; Priority pecies
South-west England, Wales and RoI, spreading north and east
30–70 (can be up to 400)
Mainly large roof voids of old buildings
Underground sites*
Woodland and parkland
Throughout the UK during migration; resident in Northern Ireland
1–100
Buildings
Buildings
Woodland, especially near water bodies
Widespread in UK and RoI
20–100+
Old stone buildings and large, timbered barns; tree holes; bat boxes
Tree cavities, bat boxes and underground sites*
Woodland and parkland
England and Wales; absent from Ireland
15–50 (can be up to 100)
Tree cavities, occasionally buildings
Tree cavities
Woodland, pasture and lakes
Largely confined to counties south of Lincolnshire and Ceredigion but may be spreading north and west
15–30
Buildings
Buildings; rarely underground sites*
Woodland, pasture and lakes
Throughout the UK and RoI
50–1,000 (2,000 exceptional)
Buildings, bat boxes and trees
Buildings, bat boxes, and tree cavities
Widespread, especially near water bodies
Throughout the UK and RoI
30–200
Mainly roof voids of older houses
Underground sites*
Woodland, gardens, parkland, hedgerows; around water bodies
Priority
Priority
Bats in the UK
Bat Conservation Trust There are 18 known bat species in the UK, 17 of which breed here and account for more than a quarter of the mammal species in the UK.
13
The outlined boxes in that table indicate the bat speices that are currently known to exist in the Hooke Park. 6/3/09 00:37:45 29128_Text.indd 13
6/3/09 00:37:46
About Bats
51
About Bats 2. Bats in Hooke Park
2.1 Bats Species of Hooke Park
The table of the right shows photos and the distribution maps of the three possible species in Hooke Park. The common pipistrelle is the most common bat species in the UK so it is quite likely that the common pipistrelle is the pipistrelle species that was found in Hooke Park. However, considering that Dorset is the home of many UK bat species, it is also possibe that it could be either Soprano pipistrelle or Nathusius’ pipistrelle. Although two bat species have been confirmed, it doesn’t mean that there aren’t more bat species that exist in Hooke Park. In fact, through research and discussions with Danielle Linton, it was revealed that 15 or the 17 bat species are known to exist within this area of Dorset. More importantly, Hooke Park is an ancient woodland that is an ideal and attractive location for foraging bats, so it is likely that Hooke Park accommodates the rarer bat species of UK.
52
Bat Conservation Trust
Serotine bat Eptesicus serotinus Introduction
The serotine is one of Britain’s largest bat species and usually one of the first to appear in the evening, often emerging in good light. Its broad wings and a leisurely, highly manoeuvrable flapping flight with occasional short glides or steep descents are distinctive.
Vital statistics
Serotine
Head & body bo length: Forearm length: Wingspan: Weight: Colour:
58mm - 80mm
48mm - 55mm Bat Conservation Trust
320mm - 380mm 15g - 35g Fur dark brown above, pale underneath; face and ears black.
Common pipistrelle General
Common pipistrelle
Diet
pipistrellus Most of the food is caught within 2km of the roost although Pipistrellus In spring, mainly flies and moths; in summer, particularly chafers serotines may forage up to six kilometres. Having caught a large and dung beetles. beetle, a serotine will fly around slowly, chewing its prey and Introduction & life dropping the wing cases and legs; sometimes it will the prey Reproduction Pipistrelles are take the commonest and most widespread of allcycle British bat species. There are two Maternity colonies consist almost bats and to a feeding perch. very similar species, common pipistrelle and soprano pipistrelle. exclusively Pipistrelles of arefemale the bats that to build up injerky May.inNumbers in smaller colonies are10most to see.toTheystart appear fast and flight as they dodgematernity about pursuing It flies at about tree-top height (to you about m) likely often close are often stable from the end of May. A colony usually insects which theonbats and eat on the wing. A single pipistrelle can consumeremains up to vegetation, and will sometimes flop,small wings outstretched, to catch at a single roost site during the breeding season, although larger 3,000 insects in one night! the foliage to catch large insects. The serotine will feed around colonies sometimes change roosts. Females normally give birth street lamps and even catch prey from the ground. to a single young in early July, though births as late as midVital statistics Bat Conservation Trust August have been recorded. The baby is occasionally carried Habitats Head & body bo length: 35mm - 45mm by its mother for the first few days. At 3 weeks the young are Serotines roost mainly in buildings with highlength: gables and cavity30mm Forearm - 35mm able to make their first flight and at 6 weeks they can forage for walls. They can be found in much older buildings and churches,200mm-235mm Wingspan: themselves. The colony usually disperses by early September, but are less often found in modern buildings. Weight: The access to the3g - 8g but a few bats may remain in the roost until early October. roost is usually at or near the gable apex or the lower eaves.Medium Colour: to dark brown. Face and around the eyes usually dark. The serotine is one of the most building-oriented species and is The males probably remain solitary or in small groups but are Pipistrellus hardly ever found in trees. occasionally foundpygmaeus with females in spring or autumn. Mating General General normally takes place insingly the autumn, but groups almost through nothingthe is The two commonest pipistrelle species found in the UK, the Male bats usually roost or in small They roost hidden in crevices around chimneys, in cavity Introduction the mating behaviour. Males and females reachJuly sexual common and soprano pipistrelle, as separate summerofmonths. During the main mating period from to walls, between felt or boardingwere andonly tilesidentified or slates, beneath known Pipistrelles are the commonest and most widespread of all British bat species. There are two maturity a year after their birth. species in the 1990s. The two species look very similar and often early September, males defend individual territories as mating floorboards and sometimes in the open roof space at the ridge very species, common and soprano pipistrelle. Pipistrelles are the‘songflights’ bats that the easiest way to tell them apart isalong fromsimilar the frequency of their pipistrelle roosts, attracting females by making repeated ends or occasionally elsewhere the ridge. Droppings Echolocation are most to see. They appeartheir fast roost and jerky in flightsocial as they dodge about pursuing echolocation calls.in large amounts you around and singing calls. are often present at gable endslikely or around a The echolocation calls of serotine bats range from 15 to 65kHz small insects whichshow the bats and eat on the wing. A single pipistrelle can consume up to chimney base, although some long-established colonies no catch and peak at 25 to 30kHz. On a bat detector a sound like irregular Habitats Echolocation 3,000 insects in one night! obvious signs of occupation where the roost is in a cavity wall. hand-clapping is heard. Bat Conservation Trustpipistrelles are above the range Common pipistrelles feed in a wide range of habitats comprising Sounds produced by common The point of access is not well-marked, though sometimes it is woodland, hedgerows, grassland, farmland, suburban and also of human hearing with the exception of social calls that may be Distribution & conservation Vitaltostatistics slightly discoloured and there are likely be aroost few around droppings urban areas. They generally emerge from their 20 heard by children and some adults with good hearing. With a bat The serotine is one of our less Head & body bo length: 35mm - 45mm underneath. minutes after sunset and fly 2-10m above ground level searching detector (heterodyne) the echolocation calls can be picked up common species, occurring mainly Forearm length: 29mm - 34mm Serotines sometimes roost inthey the catch same and building pipistrelles for their insect prey, which eat onasthe wing by between about 45 and 70kHz. south of a line drawn from The Wash Wingspan: 190mm - 230mm or long-eared bats, and they have also been known to associate The calls sound like a series of clicks towards the top of this ‘aerial hawking’. to parts of South Wales. Weight: 3g - 8g with natterer’s, and noctule bats. Pipistrellus nathusii Summer roosts whiskered of both common and soprano pipistrelles are range, turning into ‘wetter’ slaps withthe the deepest sounding Colour: Medium to dark brown. Face and usually pink inslap Thearound decline eyes in serotine numbers Very fewfound serotines are found in winter, it is likely thatnewer mostcolour. usually in crevices around the but outside of often being heard at about 45kHz, the peak intensity of the call. is probably due to loss of feeding hibernate in buildings. It is possible that at least part of the buildings, such as behind hanging tiles, soffit and barge or eaves Introduction habitat where large insects such as Distribution & conservation General General summer mayroofing remainfelt in the building forcavity some,is ifanot boarding,colony between andsame roof tiles orpipistrelle in walls. Nathusius’ rare bat in the UK, though records have increased in recent years. It chafers canable be to found. Asatthe The common pipistrelle is widely Theoftwo commonest pipistrelle species foundhave in the UK, the After about four weeks the young are fly and sixserotine weeks all, the winter period. Hibernating serotines been found is aand migratory species, andinmost bats are encountered in autumn, although some do remain all it This species also roosts in tree holes crevices, and also roosts almost entirely buildings, distributed across thein UK and its common and soprano pipistrelle, were onlyVery identified asthey separate they are able to forage for themselves. inside cavity walls and disused chimneys. rarely have year and breed in thesoprano UK. It is similar in appearance to, butisslightly larger than the much more bat boxes. Summer roosts support smaller colonies than subject to the effects of building distribution appears to extend further species in thein1990s. The two species lookeither very similar and often Male bats usually roost singly been found the coldest parts of caves, in roof crevices or in small groups through the commonly found common and soprano pipistrelles, and the fur on its back is longer, sometimes pipistrelles, with numbers averaging around 75 bats. Common work and the of toxic pipistrelle. chemicals north than thatuse of soprano theineasiest way to tell them apart is from the frequency of their summer months. During the or accumulations of boulders. main mating period from July to giving a shaggy appearance. pipistrelle maternity colonies are more likely to move between in remedial treatment. Along with timber the common pipistrelle echolocation calls. early September, males defend individual territories as mating roost sites than those of soprano pipistrelles. it is one of Britain’s commonest bat roosts, attracting females by making repeated ‘songflights’ Habitats In winter common pipistrelles areVital foundstatistics singly or in small species. around their roost and singing social calls. Soprano feed in wetland habitats, forbat example Head bo alsolength: body numbers pipistrelles in crevices usually of buildings and trees,&and in boxes.46mm - 55mm Populations of 17,pipistrelles © Bat Conservation Trustalso 2010around Photograph: Hugh Clark tree Distribution Map: Second Report by the United Kingdom under Article JNCC (2008) have over and rivers, woodland edge, lines32mm Forearm length: - 38mm Echolocation Theylakes are often found and in relatively exposed locations and rarely declined in the last Bat Conservation Quadrant House, 250 Kennington Lane, London SE11 5RD Bat Helpline 0345 1300 dramatically 228 www.bats.org.uk or hedgerows, and inTrust, suburban gardens and parks. Wingspan: 228mm - 250mm Sounds produced by soprano pipistrelles are above the range of underground. few decades. This is at least partly Weight: 16g hearing with the exception of social calls that They generally emerge from their roost around 20 minutes after6g - human may be aspecies result oftips modern agricultural Diet The left shows threeasadults bat up good close, the colColour: occasionally with frosted onmiddle the belly. sunset and fly 2-10m above ground level searching for their insectFur reddish-brown, heard by column children andthesome with hearing. practices, although common umn shows the bat species in flight and the right column shows the bat Feeds mainly on a wide range of small flies as well as the aquaticThe ears, membranes and face are usually very dark. prey, which they catch and eat on the wing by ‘aerial hawking’. With a batspecies detector (heterodyne) the echolocation calls can be distribution in Dorset. Source: Dorset Bat Group. pipistrelle populations have started showing signs of recovery midges and mosquitos. General Soprano pipistrelles appear to be more selective in their habitat General picked upyears. between about 55 and 80kHz. Thefor calls sound makes like a in recent Their reliance on buildings roosting Nathusius’ was first recorded in Great Britain in the June or early July. For three or four weeks the young are fed use than thepipistrelle more generalist common pipistrelle. Reproduction & life cycle series clicks towards the top renovations, of this range,Bats turning intoand them of vulnerable to building exclusion toxic 53‘wetter’ About ShetlandtheIslands in 1940. It was regarded aswhere a vagrant, solely on their mother’s milk. After about four weeks the young During summer, females forminitially maternity colonies they Summer roosts of both common and soprano pipistrelles are slaps withtimber the deepest sounding slap being heard at about 55kHz, remedial treatment chemicals. but its status subsequently upgraded winter visiting able to fly and at six weeks they are able to forage for give birth to a was single youngaround in June or outside earlytoJuly. For three or are usually found in crevices the of often newer the peak intensity of the call. migrant as records accumulated, and since the 1990s it has been themselves. Occasionally, maternity colonies may temporarily four weekssuch the young are fed solelytiles, on their milk. After buildings, as behind hanging soffitmother’s and barge or eaves Distribution & conservation known to breed in the UK. A small number of maternity colonies move location. about fourbetween weeks the youngfelt areand ableroof to fly and weeks they boarding, roofing tiles oratinsix cavity walls. The soprano pipistrelle is widely
Soprano pipistrelle
Soprano pipistrelle
Nathusius’ pipistrelle
Nathusius’ pipistrelle
About Bats 3. Bat Monitoring
3.1 Basic Requirements for Bat Monitoring
There are many tools that can be used for monitoring bats. On the right are some of these tools from the (top) easist to (bottom): an observational survey, a bat detector survey, installing bat boxes, and ringing bats.The more complicated techniques, such as ringing bats, will require supervision or professional help. The use of these tools can be done with one person or done with a monitoring group. On the following page, there are four simple diagrams that shows the methodology of monitoring in different scales: one point survey, path survey, and two different types of loop surveys. The key point for monitoring no matter the scale, is to go back to the same spots or same paths as many times as possible to record any changes over time.
54
Bat Conservation Trust
Sunset - Sunrise Survey
Ever sat in your garden on a warm summer evening and watched bats flitting around?
Do your bit for bats this summer
Species? (simply write ‘bat’ if you’re not sure)
Contact details Name
ID method?
Address Post Code Email address
Survey details
Visual
Type of sighting?
The Bat Conservation Trust has been counting the UK’s bats since 1997, with the help of thousands of volunteers. We need to understand what is happening to our bat populations so that we can work effectively to conserve them.
Bat detector (please note model below)
In flight
Roost
Swarming
Taking part in the Sunset-Sunrise Survey couldn't be simpler, you don’t need any equipment or experience and you do the survey in your own garden! Simply spend the hour after sunset and/or the hour before sunrise in your garden and look for any bats or other nocturnal animals you can spot.
Survey location (grid ref or post code)
Date of survey Survey type
Sunset
Sunrise
What other species did you see or hear? Rabbit
How many surveyors? Did you see bats?
Yes
No
Tawny Owl
Fox
Hedgehog
Stag Beetle
Other
You can carry out your survey anytime from April to September. This period is when bats are most active. Between June and August is the best time to see them swarming as they return to the roost.
If you are happy to be contacted by BCT with information about other bat surveys you may be interested in please tick the box
For further instructions (including videos) and to enter your results online visit www.bats.org.uk/our-work/national-bat-monitoring-programme/surveys/sunset-sunrise-survey
Observational Survey
You will need: ○ Survey form
The noctule is one of our biggest bats. They fly very high above tree tops, in straight lines and with steep dives.
Brown long-eared bats usually fly close to trees. Their flight is slow and hovering. Their long distinctive ears can sometimes be seen in flight.
○ Pencil/pen
○ Torch
○ Watch
If you are doing your survey in the evening start at sunset. If you are doing your survey at dawn start one hour before sunrise. To find out the sunset and sunrise times at your location you can enter your nearest city and the word 'sunset' or 'sunrise' into Google, or visit www.bbc.co.uk/weather or www.timeanddate.com/sun and search for your nearest city.
A observational survey is the easiest method of monitoring and can be conducted even in a garden or backyard. On the left is an example of a bat survey provided by the Bat Conservation Trust called the ‘ Sunset - Sunrise Survey’. By doing this survey, a participant will simply need the survey form, a pencil/pen, torch and a watch. Once the survey is complete, the results can be sent to the online record submission in the Bat Conservation Trust website.
Spend an hour looking for bats and any other nocturnal animals you can see or hear. Record the animals that you see on the form overleaf. After sunset you may spot bats emerging from their roost or foraging for food. Before dawn you may see bats swarming before they return to their roost - bat swarming is when several bats circle around a building or tree. You’re most likely to spot a pipistrelle. They have erratic flight with lots of twist and turns and downward swoops. There are 3 species of pipistrelle that look similar: common pipistrelle, soprano pipistrelle and the rarer Nathusius’ pipistrelle.
Which bat is it? There are eighteen species of bat in the UK, but you are most likely to see one of five species: common pipistrelle, soprano pipistrelle, brown long-eared bat, noctule or Daubenton’s bat. The form overleaf shows you how to tell them apart from their flight pattern. If you do not know which species of bat you have seen simply enter ‘bat’ on the online data entry form. Send us your results Please go to www.brc.ac.uk/irecord/external/bct-sunset-sunrise to send us your results using our online form. Thank you for your valuable contribution to bat conservation!
Daubenton’s bats fly very low over water, skimming the surface to catch insects with their feet. If you look closely you can see their white bellies.
If you have enjoyed this survey and would like to take part in other National Bat Monitoring Programme surveys go to http://nbmp.bats.org.uk/Surveys.aspx
Bat detectors we can identify many species by listening to their calls or recording them for sound analysis on a computer. Heterodyne bat detectors are the type that most people use as beginners. They are tuneable - you select the frequency range to listen to, and bat calls at that frequency are converted to sounds which you can hear. This makes them ideal detectors for immediate identification of bats in the field. Bat Detector Survey
Installing bat boxes is another method for monitoring bats. This particular bat box is commonly used ay Wytham Woods, Oxford, for bat research. They learned that bats sometimes cohabit with birds such as tits. Installing the bat box itself is not hard. However, according to law, it is illegal to distrub, harm or obstruct bats or bat roosts so touching the bat box after bats have shown to habitat the bat box will require professional help or supervision.
Installing Bat boxes
Monitoring Woodland Bats
Ringing bats require professional help or supervision from a qualified researcher. There are different sized rings depending on the bat species. The image on the left, show, undes ringed bats in a bat box in Wytham Woods. By ringing bats, researchers are able to better understand bat species’ social structure and track their movement from a local, regional and intercontinenal scale. This could also help with recording the changes in bat populations which correlates to the changes in the climate and the environment.
Wytham Woods 400 hectares
Ringing Bats
Hooke Park 150 hectares
Tagging Bats in Wytham Woods Wytham Woods
Source: Information from Bat Conservation Trust and bottom photo from in Wytham Woods, Oxford.
About Bats
55
About Bats 3. Bat Monitoring
56
3.1 Basic Requirements for Bat Monitoring
One Point Survey
Path Survey
Tools: Observational Survey Bat Detector Installing Bat Boxes
Tools: Observational Survey Bat Detector Installing Bat Boxes
The one point survey is the easiest survey to conduct and takes the least amount of time. It requires one person to conduct an observational survey such or record sounds with a bat detector to identify bat species. It is also possible to install bat boxes near the monitoring spot to see if any bat species would roost in that area.
Path surveys are similar to one point surveys except that the monitoring takes place along a short path. It is possible to conduct an observational survey but a bat detector would be useful for this type of path survey. The chosen path will run along an area known to have the presence of bats and also cover at least two types of environments (for example, one space with higher density of trees and the other with lower density of trees).
Loop Survey 1
Loop Survey 2
Tools: Observational Survey Bat Detector Installing Bat Boxes
Tools: Observational Survey Bat Detector Installing Bat Boxes Ringing Bats
A loop survey may take up to two or more hours. It requires using the bat detector along the path from start to finish. It would also be useful to arrange the path through knwon existing roosts. Similar to the path survey, it is benefitial to have the chosen path run along different landscapes, also take into consideration that bats like to follow tree lines and find bodies of water to fly around. Installing bat boxes will attract more bats to roost and forage along the path, this could help better understand the bats that live and forage in the area.
Loop survey 2 is very similar to loop survey 1 except that it welcomes more hands-on work that may require professional help or supervision. By installing bat boxes along the loop, participants (together with professional help) will be able to tag and ring the bats for monitoring and research. The more bat boxes along this loop, the better, This gives a chance for bats to find the ideal roosts and will give the participants a better chance of finding them.
Four simple diagrams that shows the methodology and tools for monitoring in different scales.
About Bats
57
About Bats 3. Bat Monitoring
3.2 Bat Monitoring Program in Hooke Park
3.2.1 Participants of Monitoring Program
The aim of a wildlife monitoring program is welcome other groups and organizations to teach and share their expertise. The monitoring program will welcome educational organizations such as Hooke Court and research and conservation groups such as the Dorest Wildlife Trust, the Dorset Environmental Records
The Architectural Association can assist and contribute to the wildlife monitoring program by including both students and staff from Hooke Park or Bedford Square to participate.
Centre, the Dorset Bat Group, the Dorset Bird Club and the Dorset Countryside Volunteer. Hooke Court is a specialist educational centre for children of different ages. Including these children in the wildlife monitoring program could be an educational experience as well as a way to contribute to recording data.
Dorset Wildlife Trust is a charity dedicated to nature conservation. They are involved in monitoring and improving habitats for wildlife with volunteers. Hooke Park could be opened to the DWT for more data recording.
Dorset Environemntal Records Centre (DERC) maintains a Dorset Wildlife Recorders Register. Anyone is allowed to submit data or recordings of wildlife to DERC, including the data recorded in Hooke Park.
The Dorset Bat Group helps record and protect the bats of Dorset. They are an oragnization run mainly by volunteers and would be interested in monitoring the bats of Hooke Park.
The Dorset Bird Club is another organization that record and protect the birds of Dorset. They are an organization run mainly by volunteers and would be interested in monitoring the birds of Hooke Park.
An organization in Dorset that carry out practical conservation work. They do not own any sites or land but work on land owned by other organizations such as the National Trust, Dorset Wildlife Trust or local authorities. This would be a group that Hooke Park can work with.
A part of creating a more long-term program is to include participants from both the AA institutional body and external parties. Above is a list of establishments that could play an important role in the program.
58
There are 15 mapped tree species within the boundaries of Hooke Park, the two most dominating being the Beech and the Norway Spruce. Each cluster succeeds in formulating its own environment, creating a plethora of different conditions to explore through the seasons.
From Beamister or Crewkerne
AS
Ash
BE
Beech
OA
Oak
SY
Sycamore
NS
Norway Spruce
DF
Douglas Fir
RO
Red Oak
MB
Mixed Broadleaf
SC
Sweet Chestnut
CP
Corsican Pine
PO
Poplar
RC
Red Cedar
AL
Alder
LA
Larch
SS
Sitka Spruce
From Hooke P
From Hooke
P
Woodland boundary
From Maiden Newton
Hooke Park woodland boundary Trails/Roads Waterways Hooke Park primary structures Hooke Park secondary structures Bird Transect Bat Transect Car Route
TREE SPECIES MAP Ele Mun, 2019
Source: Hooke Park, Zachary Mollica
P
Car Park N
Map of Hooke Park, indicating the tree species, woodland boundaries, roads, trails, waterways, structures and two example transects and the car routes for participants and external visitors.
About Bats
59
About Bats 3. Bat Monitoring
3.2 Bat Monitoring Program in Hooke Park
3.2.2 A Monitoring Transect
The monitoring transect is dependent on scale of the program and the logistical resources to run this program. Based on the requirements of a transect, two transects were identified: one long transect and one short transect. Both transects will begin on campus. The campus will be the start-and-end meeting point for all monitoring groups. The long transect will cover most of Hooke Park’s woodland. It will go through areas with dense monocultural tree species, areas with clear tree felling, and also areas with dense mixed tree species. It will also follow along a stream where bats might find an attractive place for foraging. The path will also follow some wider trails as bats might find the tree lines to follow. The whole loop will take about 2 hours or more depending on the extensiveness of monitoring conducted. The short transect will mostly follow walking trails from campus to the stream and back. Unlike the long transect, it will not go through the tree felling areas, but will mostly cover the campus cleared areas to the areas with mixed trees by the pond or stream, south of the campus. The whole loop will take about 45 mins or more depending on the extensiveness of monitoring conducted.
60
There are 15 mapped tree species within the boundaries of Hooke Park, the two most dominating being the Beech and the Norway Spruce. Each cluster succeeds in formulating its own environment, creating a plethora of different conditions to explore through the seasons.
AS
Ash
BE
Beech
OA
Oak
SY
Sycamore
NS
Norway Spruce
DF
Douglas Fir
RO
Red Oak
MB
Mixed Broadleaf
SC
Sweet Chestnut
CP
Corsican Pine
PO
Poplar
RC
Red Cedar
AL
Alder
LA
Larch
SS
Sitka Spruce Woodland boundary Hooke Park woodland boundary Trails/Roads Waterways Hooke Park primary structures Hooke Park secondary structures Bat Transect (short) Bat Transect (long) Car Route
TREE SPECIES MAP Ele Mun, 2019
Source: Hooke Park, Zachary Mollica
N
Map of Hooke Park, indicating the tree species, woodland boundaries, roads, trails, waterways, structures and two bat transects and the car routes for participants and external visitors.
About Bats
61
About Bats 3. Bat Monitoring
3.2 Bat Monitoring Program in Hooke Park
3.2.3 Long-term Vision
The long-term vision of the wildlife monitoring program in Hooke Park is to have an officially defined monitoring transect, that caters to the monitoring of the prioritised species such as birds, bats or insects. The aim is encourage AA students to learn more about the woodland and also to welcome third parties to come to Hooke Park to conduct monitoring for scientific interest. This wildlife monitoring program will not only help the Hooke Park forester with managing and balancing the woodland’s biodiversity and build a wider community for woodland managment, but the program will also help management and biodiversity in the wider context. Most of the local groups and organizations conduct monitoring on the land of Trusts (such as the National Trusts, Woodland Trusts, Dorset Wildlife Trusts). However, private woodland owners (who own some of the most valuable ancient woodlands in the country) do not do enough. Hooke Park, being an educational institution, has the resources to collaborate and contribute to the scientific study and the improvement of biodiversity. It is setting a stage for other private land owners to rethink about how woodlands can be managed to protect the vulnerable unique wildlife and landscape. The extent of the monitoring (for example, the level of tools used) will ultimately depend on Hooke Park’s willingness to install bat boxes and apply rules to bat monitoring. There are legal and logistical rules to consider because once bat boxes are installed, it could alter the timber production aspect of Hooke Park. However, the program itself is quite simple in the sense that it will ultimately rely on the willingness of the AA student body and the participation of local groups (such as the Dorset Bat Group, the Dorset Bird Club, the Dorset Wildlife Trust, the Woodland Trust and more).
62
Bat monitoring group using bat detectors. Source: National Trust Jersey.
About Bats
63
64
Part 2 Rules and Guidelines for Bat Roost Architecture 1. Information on Bat Roosts
1.1 Bat Roost Typology
1.2 Bat Roost Preferences of UK Bat Species
2. A Case Study: Existing Bat Roosts of Hooke Park
2.1 The Campus
2.1.1
The Big Shed
2.1.2
Westminster Lodge
2.1.3
The Caretaker’s House
3. Methods of Incorporating Bat Roosts into Architecture 4. Existing Ready-made Products 5. Bat Roost for Crevice-Dwelling Bats 6. Playing with the Rules of Architecture
65
Rules and Guidelines for Bat Roost Architecture 1. Information on Bat Roosts
1.1 Bat Roost Typology
1
2
2 1
3
2 4
5
Roost in Caves
Bat Roost in Trees
Cracks in rocks
1
2
Navigational aid
1
Dark tunnels
Crack in tree
2
3
Underground tunnels or caves are ideal for hibernation because they are less likely to be disturbed by light, noise and predators. Of all UK bat species, greater and lesser horseshoe bats rely most heavily on caves for roosting sites.
66
Bat Roost i
Stone p
1
2
Slate
Rotten hole
4
Behind the ivy plant
5
Under the tree bark
Bats enjoy roosting in trees. They look for any cracks, woodpecker holes, holes in the tree truck and ive leaves. They also use the shape of the tree for echolocation which helps them navigate. However, the number of bats that roost in trees are unknown due to the difficulties in conducting this research.
Stone bridges are most like sites, particularly over water be used and the abutments or can contain crevices which ma quire different roosts at any ti micro-climate conditions pro
1 1
2
3 2
3
4
4
1 5
6
5
Bat Roost in Houses
in Bridges
pieces
1
Barge board and roof felt
e tiles
ely to provide suitable roost r. Concrete bridges may also r stell and wooden structures ay be utilised by bats. Bats reime of the year, depending on ovided by various roost sites.
Bat Roost in Buildings
Broken tiles
2
3
4
1
2
Space between downpipe Metal elements on balconies
Eaves
Hanging tiles 5
Porch
6
Cellar
Bats may prefer houses because they are cleaner, warmer and more suitable than trees and other natural sites, with less competition from birds and other animals. The choice of building is complex and its suitability from a bat perspective depends on structure, location, microclimate, and human use. Habit also plays a part. Bats are long-lived with excellent memories and may use the same house each year in a row of seemingly identical houses.
3
4
Quoins
Loose motar between bricks 5
Wood cladding
Bats can also live in modern buildings. They tend to find crevices and gaps within the structure. However, more and more buildings are becoming air sealed and are also made from materials that are harmful to bats. This is one factor that has contributed to the decline of bat populations.
Source: Bat Conservation Trust: Bat Roosts.
Rules and Guidelines for Bat Roost Architecture
67
Rules and Guidelines for Bat Roost Architecture 1. Information on Bat Roosts
1.2 Bat Roost Preferences of UK Bat Species
According to the book ‘Designing for Biodiversity: A technical guide for new and existing buildings’ by K. Gunnell, B. Murphy and Dr. C. Williams, there are four categories within which the UK bat species fall: Crevice-dwelling bats (that tend to be hidden from view) Crevice-dwelling bats (that may be visible on roof timbers) Crevice-dwelling bats (require flight space in certain types of roost) Bats that need flight space and flying access On the following page, the table shows the general outline of roosting and nesting requirements for each of the above mentioned categories. It is important to note that the four categories represents an arbituary grouping and that the detail of how bats choose their bat roost is much more complicated and it need of further study. The type of roost (maternity, non-breeding adults, transitory, mating, hibercula, night or feeding roosts) and the part of the country the bat is located in will make a difference in what a bat requires of the roost.
68
Common name
Crevice-dwelling bats (hidden from view)
Crevice-dwelling bats found in roofvoid (roof timber)
Crevice-dwelling bats found in roofvoid (flight space)
1
Barbastelle
•
2
Bechstein’s bat
•
3
Brandt’s bat
4
Brown long-eared
5
Common pipistrelle
6
Daubenton’s bat
7
Greater horseshoe bat
8
Greater mouse-eared bat
•
9
Grey long-eared bat
•
10
Leisler’s bat
11
Lesser horseshoe bat
12
Nathusius’ pipistrelle
13
Natterer’s bat
14
Noctule
•
15
Serotine
•
16
Soprano pipistrelle
•
17
Whiskered bat
•
Bats that need flight space and flying access
• • • • •
• • • •
Bat Roost Preferences of UK bat species Source: Designing for Biodiversity: A technical Guide for new and existing buildings by K. Gunnell, B. Murphy and Dr. C. Willamas.
Rules and Guidelines for Bat Roost Architecture
69
Rules and Guidelines for Bat Roost Architecture 1. Information on Bat Roosts
1.2 Bat Roost Preferences of UK Bat Species
Crevice-dwelling Bats (that tend to be hidden from view)
Access Dimensions
Roosting/Nesting Dimensions
Height of Entr
20 - 50mm (w) x 15 - 20mm (h)
Any size as long as some components of the area are crevices in the region of 20 - 30mm
2 - 7m
Greater total areas of about 1sq m would be useful for nursery (summer) roosts Male roosts contain smaller numbers of bats or even individual bats Roof dwelling bats need timber joists or beams on which to roost
Crevice-dwelling Bats (that may be visible on roof timbers)
20 - 50mm (w) x 15 - 20mm (h)
Any size as long as some components of the area are crevices in the region of 20 - 30mm
Over 2m
Greater total areas of about 1sq m would be useful for nursery (summer) roosts Male roosts contain smaller numbers of bats or even individual bats Roof dwelling bats need timber joists or beams on which to roost
Crevice-dwelling Bats (require flight space in certain types of roost)
20 - 50mm (w) x 15 - 20mm (h)
5m (w) x 2.8m (h) x 5m (d)
Over 2m
Not trussed, to allow flight Ideally 2.8m height, but a height of 2m may be acceptable in some circumstances To incorporate roost crevices, dimensions as above for crevice-dwelling bats
Bats that need flight space and flying access (Horseshoe bats)
70
Lesser horseshoe bats: 300 (w) x 200mm (h) Greater horseshoe bats: 400mm (w) x 300mm (h)
5m (w) x 2.8m (h) x 5m (d) Not trussed, to allow flight Ideally 2.8m height, but a height of 2m may be acceptable in some circumstances
At least above 5m abo ground and away from structions and creepe
Preferably integral to building, but where th possible externel, e.g. eaves
ry
ove m obers
the his is not under the
Aspect of Roost
Summer nusery roosts on most southerly side or westerly aspect for solar heating. However, the risk of overheating should be considered. A location that provides a stable microclimate/ regime mmay work better than one that heats up quickly and loses heat quickly
Temperature °C Summer
Winter
30 - 40 °C (day time temperature)
0 - 6 °C
Materials and Other Comments
Rough (for grip), natural materials such as untreated timber, stone or masonary is preferred Not toxic or corrosive and no risk of entanglement Suitable thermal properties (reducing 24-hour fluctuations), but allowing suitable thermal gain for summer roosts
Male roosts and winter hibernatiion roosts on notherly aspect
North facing boxes used for hibernating will benefit from using insulation materials. Larger crevice spaces (particularly in the vertical dimension) can provide a range of temperatures, which will allow the bats to move according to their temperature needs Access not lit by artificial lighting The crevice-roosting provision within the roost to be located on the south or west side for solar heating. or in the most thermally stable condition
30 - 40 °C
0 - 6 °C
Rough (for grip), natural materials such as untreated timber, stone or masonary is preferred Not toxic or corrosive and no risk of entanglement
The location of the flight area is not as important
Suitable thermal properties (reducing 24-hour fluctuations), but allowing suitable thermal gain for summer roosts North facing boxes used for hibernating will benefit from using insulation materials. Larger crevice spaces (particularly in the vertical dimension) can provide a range of temperatures, which will allow the bats to move according to their temperature needs Access not lit by artificial lighting
The crevice-roosting provision within the roost to be located on the south or west side for solar heating. or in the most thermally stable condition
30 - 40 °C
0 - 6 °C
Rough (for grip), natural materials such as untreated timber, stone or masonary is preferred Not toxic or corrosive and no risk of entanglement
The location of the flight area is not as important
Suitable thermal properties (reducing 24-hour fluctuations), but allowing suitable thermal gain for summer roosts North facing boxes used for hibernating will benefit from using insulation materials. Larger crevice spaces (particularly in the vertical dimension) can provide a range of temperatures, which will allow the bats to move according to their temperature needs Access not lit by artificial lighting
The roost is most likely to be in a roof space; this should have an orientation that allows a south-facing solar gain or an L-shape to allow temperature-range choice
30 - 40 °C
6 - 10 °C
Rough (for grip), natural materials such as untreated timber, stone or masonary is preferred Not toxic or corrosive and no risk of entanglement Suitable thermal properties (reducing 24-hour fluctuations), but allowing suitable thermal gain for summer roosts North facing boxes used for hibernating will benefit from using insulation materials. Larger crevice spaces (particularly in the vertical dimension) can provide a range of temperatures, which will allow the bats to move according to their temperature needs Access not lit by artificial lighting
General Outline of roosting and nesting preferences Source: Designing for Biodiversity: A technical Guide for new and existing buildings by K. Gunnell, B. Murphy and Dr. C. Willamas.
Rules and Guidelines for Bat Roost Architecture
71
Rules and Guidelines for Bat Roost Architecture 2.1 The Campus
PG
EPIP
EPIP
2. A Case Study: Existing Bat Roosts of Hooke Park
There are 15 permanent buildings in Hooke Park campus, constructed in different years (some of which were built before AA taking ownership in 2002). Of these 15 permanent buildings, three buildings have shown to have or attempted to have accomdate bat roosts: the Big Shed, the Westminster Lodge, and the Caretaker’s House. These three examples of bat roosts discovered through the testimonies of PG
Hooke Park’s full time staff, who have lived through the changes over the years.
Saw Mill Shelter
PG
However, there could be more bat roosts within these permanent buildings that is still yet to be discovered as there has never been a full formal bat survey conducted on campus. In the following pages, the Big Shed, the Westminster Lodge and the Caretaker’s House will be case studies that examine why these buildings became successful or
Wood Chip Barn
EPIP
unsuccessful bat roost spots.
GP
PG
PIPE
72
EP
IP
EPIP
GP PE
EPIP
PG
PG
PI
Timber Shelter
1
Student Lodge EPIP
The Big Shed
Student Lodge
PG
Wakeford Library
3
The Refactory
The Caretaker’s House
The Workshop
PG
Boiler House
2
Westminster Lodge
PIPE
GP
N
An illustrated map of Hooke Park Campus. The three labeled buildings are the strctures in which have evidence of bat roost.
Rules and Guidelines for Bat Roost Architecture
73
Rules and Guidelines for Bat Roost Architecture 2. A Case Study: Existing Bat Roosts of Hooke Park
2.1 The Campus
The annual temperature graph shown on the right illustrates the temperature range annually in Exeter. As there was no data for Hooke Park, the closest weather data is going to be used for this study. The average temperature range within that area ranges from 3 째C (coldest in February) to 23 째C (warmest in August). The warm season lasts for 3 months, from June 15 to September 17 and the The cool season lasts for 4 months, from November 22 to March 24. According to the Bat Roost Preferences for UK bat species, most crevice-dwelling bats can withstand the coldest temperature in this area. However, bats that need flight space and flying access to their roosts (particularly horseshoe bats) might find the winters too cold as their winter roost temperature range is 6 째C - 10 째C.
74
Source: EnergyPlus Weather Data.
Rules and Guidelines for Bat Roost Architecture
75
Rules and Guidelines for Bat Roost Architecture 2. A Case Study: Existing Bat Roosts of Hooke Park
2.1 The Campus
The diagram on the right shows the solar analysis of Hooke Park in January (top row) and in June (bottom row). It seems that almost all the structures have sun exposure in both winter and summer. By comparing the solar anaylsis on the permanent structure volumes in Hooke Park, it shows that the Big Shed and the Caretaker’s House recieves the most sun exposure annually. This solar analysis model shows the general volumes but does not take into
1
The Big Shed
account the surrounding trees that are at the edge of the campus. The surrounding trees may have an impact of the sun exposure on the structure volumes. The Big Shed and Caretaker’s House do not have many surrounding trees that might affect
3
the sun expsoure. However, Westminster Lodge have many surrounding trees on
The Caretaker’s House
the South side of the structure which could affect the overall sun exposure annually (not depicted in this solar analysis model).
2
Westminster Lodge
Hooke Park in January (Top View) Sunlight Hours: 9am-3pm
1
The Big Shed
3
The Caretaker’s House
2
Westminster Lodge
Hooke Park in June (Top View) Sunlight Hours: 9am-3pm
76
Hooke Park in January (Southwest View) Sunlight Hours: 9am-3pm
Hooke Park in June (Southwest View) Sunlight Hours: 9am-3pm
Rules and Guidelines for Bat Roost Architecture
77
Rules and Guidelines for Bat Roost Architecture 2. A Case Study: Existing Bat Roosts of Hooke Park
2.1 The Campus
2.1.1 The Big Shed
The Big Shed was designed by students of Design & Make and Diploma Unit 19 in 2012, with the support from engineers Atelier One and architects Mitchell Taylor Workshop. It provides a large enclosed workspace for fabrication, assembly and prototyping activities at Hooke Park. The building is constructed from larch sourced from Hooke Park and local woodlands, and uses innovative screw connections to form the roundwood trusses. A year ago, a bat hox was placed by the forester in the interior of the shed to accomodate the bats in the area. However, a year later, there is still no sign of bat inhabitation. According to the bat expert, Nick Tomlinson (who was on site), there are a few known reasons why bats have not inhabit the bat box: 1
The vertical distance from the access point of the bat box.
When bats exist their roosts, they tend to drop from the access point before they can fly again. This vertical distance is usaully a little less than or about 1 m. The image on the top left shows that distance is not enough for the bats to drop from their access point. If bats were to land on the metal beam below the access point, they may put themselves in a vulnerable position and a target for predatory birds such as owls. This bat box could be orientated outwards so that there is a vertical drop distance from the entry point. 2
The placement of the bat box with no optimized warmth.
Bat Box
Bats will seek for bat roosts that keep them warm. The placement of the bat box may indicate that it doesn’t get warm enough in the winter. It may be more useful to place it in a location where sun can reach surfaces to warm up the roost. 3 Another reason in which bats may not find this bat box ideal is that the interior
of the Big Shed is filled with horizontal beams. There has been evidence that owls like to perch on these beams and may find this the perfect location to prey on bats if they were present. On a positive note, the height as shown on
4
is well placed. Bats like to inhabitat
places far from the ground. The placed height of the bat box is above 2m which is more than ideal for bats.
N
Top: Photo of the Bat box installed inside the Big Shed. Bottom: Plan of Big Shed indicating the location of the bat box.
78
2
3
1
4
Perspective drawing on the Big Shed interior. The drawing shows that the bat box is placed at height above 2m but the box is placed in the wrong orientation.
Rules and Guidelines for Bat Roost Architecture
79
Rules and Guidelines for Bat Roost Architecture 2. A Case Study: Existing Bat Roosts of Hooke Park
2.1 The Campus
2.1.2 Westminster Lodge
Designed by Edward Cullinan Architects with engineer Buro Happold in 1996, the Lodge uses green wood from Hooke’s forest, providing eight bedrooms around a central communal space. A timber lattice of spruce thinnings carries a planted turf roof. According to Charlie, Hooke Park’s workshop staff, there were two instances in which he heard or saw the presence of bats. The first was when he encountered bats while checking the boiler cupboard under the lodge. The second time, he was informed by a group of students from experimental school that were staying at the lodge that a bat was in one of their rooms. With this information, a study was conducted with the bat expert to find out more how bats might or might have inhabit Westminster Lodge. It turns out that the bats have entered through the gap of the concrete pile Southeast of Westmister Lodge. The gap reaches the boiler cupboard which is particularly warm in the winter months. From inside the cupboard, bats can crawl top through the waterproof sheet and along the horizontal beams. Evidence of bat droppings were found and the bat expert indentified that it was most likely a maternity colony that stayed in these cracks and crevices. He also said that it is best to leave it alone, as female bats (depending on species) tend to find their way back to the same maternity roosts year after year. On the following page, shows an image of where the bats manage to enter into the lodge. The bats which may have entered through the gap above the concrete pile could have possibly found their way into the void behind the showers. The image shows that there are some gaps in the walls above the shower in which the bat may have crawled into the reach the room. Bat Presence
N
Top: Photo of Westminster Lodge (Southwest vew) Bottom: Plan of Westminster Lodge indicating the location of bat presence.
80
Perspective drawing of Westminster Lodge (Southwest view), indicating the access route and location of bat roost in Westminster Lodge.
Rules and Guidelines for Bat Roost Architecture
81
Rules and Guidelines for Bat Roost Architecture 2. A Case Study: Existing Bat Roosts of Hooke Park
2.1 The Campus
2.1.2 Westminster Lodge
Bat Presence
N
Top, Left: Photo of bat access and presence inside the lodge Bottom: Plan of Westminster Lodge indicating the location of bat presence.
82
Perspective drawing of Westminster Lodge (Southwest view), indicating the access route in Westminster Lodge.
Rules and Guidelines for Bat Roost Architecture
83
Rules and Guidelines for Bat Roost Architecture 2. A Case Study: Existing Bat Roosts of Hooke Park
2.1 The Campus
2.1.3 The Caretaker’s House
The Caretaker’s House at Hooke Park is based on a schematic design by students of AA’s Intermediate Unit 2 in 2009-10, which was developed for construction by architect Invisible Studio. It is a prototypical low cost timber exemplar building constructed from timber grown and felled on site. According to Charlie who lives in the Caretaker’s House, he has seen a group of bats come out from the roof in the early summer months. The drawings on the right show the location in which the bats have shown presence.
First
A study was conducted with the bat expert, Nick Tomlinson, to find out more how bats inhabit the roof space of the Caretaker’s House. He believes that there is gap between the corrogated metal roof sheet and the structural volume. It is possible that the bats crawl along the horizontal beams of the roof and inhabit as a colony in a row. He also believes that the extended part of the roof allows for bats to come out of the bat roost safely away from predatory birds. This is because bats tend to drop from the exit point before finding their balance in flight. With the extended roof, it allows for bats to be protected before foraging into the woods.
Ground What is interesting about this particular structure is that it is not the oldest building at Hooke Park. It is only about 10 years old, whilst some of the other structures were built in the 1980s. It is common preconception that bats like to live in old buildings.In reality, bats are quite opportunistic mammals and with the right environmental conditions, bat will find a place to roost whether new or old.
Bat Presence
N
Top: Photo of Caretaker’s House (Southwest vew) Bottom: Plan of Caretaker’s House indicating the location of bat presence.
84
Bat Presence
A section drwaing of Caretaker’s House indicating where the bats enter into the roof.
Rules and Guidelines for Bat Roost Architecture
85
Rules and Guidelines for Bat Roost Architecture 2. A Case Study: Existing Bat Roosts of Hooke Park
2.1 The Campus
2.1.3 The Caretaker’s House
A solar study was conducted on the Caretaker’s House. Using weather data that is applied on the sun path diagram, the diagrams on the right show the sun exposure of the structure in the winter and summer. The diagrams on the top row shows the Caretaker’s House in the winter month of January, illustrating the amount of sun exposure from 9am to 3pm. It indicates that more than two-thirds of the roof surface receives 6 hours or more sun exposure. The part of the roof that recieves the least sunlight is the steepest slant part of the roof, which recieves about 4 or more hours of sun exposure in the month of January The diagrams on the bottom row shows the Caretaker’s House in the summer month of June, illustrating the amount of sun exposure from 9am to 3pm. It indicates that the entire roof surface receives 6 hours or more sun exposure. This solar study shows that more than two-thirds of the roof recieves sun exposure throughout the year, so why is that the bat colony is only present on the left part of the roof? The bat expert explains that it is possible that the bat found that part of the roof the most ideal roost site due to its height and distance from possible human encounters at lower height levels.
Caretaker’s House in January (Top View) Sunlight Hours: 9am-3pm
Caretaker’s House in June (Top View) Sunlight Hours: 9am-3pm
86
Caretaker’s House in January (Southwest View) Sunlight Hours: 9am-3pm
Caretaker’s House in June (Southwest View) Sunlight Hours: 9am-3pm
Rules and Guidelines for Bat Roost Architecture
87
Rules and Guidelines for Bat Roost Architecture 2. A Case Study: Existing Bat Roosts of Hooke Park
2.1 The Campus
2.1.3 The Caretaker’s House
1 2
2
5
4
3
Detailed roof section of the Caretaker’s House
1
Corrogated metal roof sheet Timber beam
2
Insulation
3
4
5
88
Dry wall
Interior space
The diagram above is a temperature variation study of the detailed roof section of the Caretaker’s house in January. The interior space is at a room temperature of 21 oC and the external temperature is at 3 oC (which is the average minimum temperature in the winter). It may be that the heat loss the travels through the insulation reaches between the insulation cover and roof sheet, which creates an warm shelter for the bats in the winter.
The diagram above is a temperature variation study of the detailed roof section of the Caretaker’s house in June. The interior space is at a room temperature of 21 oC and the external temperature is at 23 oC (which is the average mamimum temperature in the winter).
The diagram above shows the heat flux of the detailed roof section of the Caretaker’s House. Considering that there were very few materials used for this structure, mostly timber, wood fibre insulation and the corrogated metal roof sheet, the overall heat flux is very low and distributed quite evenly.
Left to Right: Detailed section of roof; temperature variation of roof section in January, temperature variation of roof section in June; and heat flux of roof section.
Rules and Guidelines for Bat Roost Architecture
89
Rules and Guidelines for Bat Roost Architecture 3. Methods of Incorporating Bat Roosts into Architecture
There are two ways in which bats could choose their roost sites within architecture. The first one comes naturally. Without any human intervention, bats find their way into cracks and crevices that were not intended for them. This has shown to have worked mostly in historical buildings in which had many cracks and crevices. The second method is to design and apply strategically bat roost architecture, considering the environmental requirements of bat roosts. This method is not always successful. Even if the environmental conditions are ideal, it might not succeed. The key to it is to give it time and consider flexibility. There may be different factors that may prove the roost architecture to not be successful. This second method is where humans try to study and understand. Why is it that bats like some structures and not others? How can we think more strategically for bats to live harmously with humans in the same structure?
Bat Roost in roof of the Caretaker’s House
Bat box in the Big Shed
90
Built strcuture (no planning, with observation over time)
Time
Built strcuture (planning, with strategic design of ideal roost)
Time
Bat inhabitation
Bat inhabitation
Rules and Guidelines for Bat Roost Architecture
91
Rules and Guidelines for Bat Roost Architecture 4. Existing Ready-made Products
The creation of bat boxes or bat roosts is not a new concept. There has been many trial and errors of products that have been in the market to accomodate bats. On the right are five example products that are intended to be used as bat roosts in architectural buildings. And in the following page are three examples of how these five products could be applied to architecture. These five products and many other products in the market have proved to be successful but these ready-made products does not mean that the building structure and the architectural design have found the best strategy to accomodate bats. There are many other parts of the building that could do with a slight change in design in order to accomodate bats and also to make use of the voids and temperature ranges that a building holds. The potential in designing for species such as bats are not researched enough and bringing the knowledge about bats and architecture can mean that we can consider how the buiding we design can cater beyond humans and that we can be more sensitive towards the surrounding environmental and cological well-being.
92
Schwegler Bat Box Usage: Outer wall construction Dimensions: 300 mm (w) x 300 m (h) x 80 mm (d) Made from woodcrete and is durable, weather resistant and air permeable. It can also be used to create access or as a roost space by the use of the optional back plate.
Roof Block Usage: Flat, hipped or any pitch roof. Outer leaf or cavity wall or halfbrick uninsulated walls to outbuildings Dimensions: - The roof block is a block with bat access slit in the bottom into the interior chamber.
Habitat Clay Bat Access Tile Usage: Replaces clay roof tile Dimensions: - The clay bat access roof tile is a five piece set and fits on any roof with plain clay tiles. Avaliable in a full range of colours, from red and brindle colors to Staffordshire blue. Provides a means for bats to crawl behind tiles.
Habitat Bat Box Usage: Replaces six clay brick slip face Dimensions: Dense aggregate or lightweight options are avaliable 215 mm (w) x 440 mm (h) x 103 mm (d) Inside the chamber are V wedges for different temperature zones and to create roosting surfaces.
Ecosurv Swift Box Usage: External elevations of buildings. Discreet nesting box for location near eaves. Dimensions: 328 mm (w) x 140 mm (h) x 200 mm (d) Access piece can be used for both bats and birds. In this particular product, the nest is withing product.
Source: Designing for Biodiversity: A technical Guide for new and existing buildings by K. Gunnell, B. Murphy and Dr. C. Willamas.
Rules and Guidelines for Bat Roost Architecture
93
Rules and Guidelines for Bat Roost Architecture 4. Existing Ready-made Products
Example 1: Insulated cavity wall and pitched roof providing space for bats and small birds
1
Habitat Clay Bat Access Tile
2
Roof Block 1 1
2
2
Detailed Section Drawing of Example 1
Detailed Perspective Model of Example 1
Example 2: Brick/block cavity wall construction eaves providing spaces for bats and birds
1
Habitat Clay Bat Access Tile
2
Schwegler Bat Box
1 1
2
Detailed Perspective Model of Example 2
94
2
Detailed Section Drawing of Example 2
Example 3: Brick/block cavity wall construction providing spaces for bats
1
Ecosurv Swift Box
2
Habitat Bat Box
3
Schwegler Bat Box
1
1
2
2
3
3
Detailed Perspective Model of Example 3
Detailed Elevation Drawing of Example 3
Detailed Section Drawing of Example
Three examples of how ready-made products are incorporated. Source: Designing for Biodiversity: A technical Guide for new and existing buildings by K. Gunnell, B. Murphy and Dr. C. Willamas.
Rules and Guidelines for Bat Roost Architecture
95
Rules and Guidelines for Bat Roost Architecture 5. Bat Roost for Crevice-Dwelling Bats
When designing for bats, it can be quite complex. There are many species of bats in the UK and each of these species have different preferences in the way they live. One way, as suggested by the bat expert, Nick Tomlinson, is to design bat roost based on the four categories of bat roost preferences: Crevice-dwelling bats (that tend to be hidden from view) Crevice-dwelling bats (that may be visible on roof timbers) Crevice-dwelling bats (require flight space in certain types of roost) Bats that need flight space and flying access He also suggested the best way to accomodate a wider range of bat species is to design for crevice-dwelling bats. This covers three of the four categories in the bat roost preferences. Crevice-dwelling bats cover a range of species from common species to rare species as shown on the table on the right. The following page highlights the requirements of crevice-dwelling bats. There are some requirements that are distinct for specific bats but for the most part, the three crevice-dwelling bats require similar basic environmental requirements (such as temperature range and access dimensions).
96
Common name
Crevice-dwelling bats (hidden from view)
Crevice-dwelling bats found in roofvoid (roof timber)
Crevice-dwelling bats found in roofvoid (flight space)
1
Barbastelle
•Rare, threatened
2
Bechstein’s bat
•Rare, threatened
3
Brandt’s bat
4
Brown long-eared
5
Common pipistrelle
6
Daubenton’s bat
7
Greater horseshoe bat
8
Greater mouse-eared bat
• Very rare
9
Grey long-eared bat
• Very rare
10
Leisler’s bat
11
Lesser horseshoe bat
12
Nathusius’ pipistrelle
13
Natterer’s bat
14
Noctule
• Threatened
15
Serotine
• Rare
16
Soprano pipistrelle
• Threatened
17
Whiskered bat
• Not threatened
Bats that need flight space and flying access
• Uncommon, not threatened •Threatened • Frequent, not threatened • Frequent, not threatened •
in • Frequent Ireland
• • Rare • Not threatened
Crevice-dwelling Bats of the UK Bat Species Source: Designing for Biodiversity: A technical Guide for new and existing buildings by K. Gunnell, B. Murphy and Dr. C. Willamas.
Rules and Guidelines for Bat Roost Architecture
97
Rules and Guidelines for Bat Roost Architecture 5. Bat Roost for Crevice-Dwelling Bats
Crevice-dwelling Bats (that tend to be hidden from view)
Access Dimensions
Roosting/Nesting Dimensions
Height of Entr
20 - 50mm (w) x 15 - 20mm (h)
Any size as long as some components of the area are crevices in the region of 20 - 30mm
2 - 7m
Greater total areas of about 1sq m would be useful for nursery (summer) roosts Male roosts contain smaller numbers of bats or even individual bats Roof dwelling bats need timber joists or beams on which to roost
Crevice-dwelling Bats (that may be visible on roof timbers)
20 - 50mm (w) x 15 - 20mm (h)
Any size as long as some components of the area are crevices in the region of 20 - 30mm
Over 2m
Greater total areas of about 1sq m would be useful for nursery (summer) roosts Male roosts contain smaller numbers of bats or even individual bats Roof dwelling bats need timber joists or beams on which to roost
Crevice-dwelling Bats (require flight space in certain types of roost)
20 - 50mm (w) x 15 - 20mm (h)
5m (w) x 2.8m (h) x 5m (d)
Over 2m
Not trussed, to allow flight Ideally 2.8m height, but a height of 2m may be acceptable in some circumstances To incorporate roost crevices, dimensions as above for crevice-dwelling bats
Bats that need flight space and flying access (Horseshoe bats)
98
Lesser horseshoe bats: 300 (w) x 200mm (h) Greater horseshoe bats: 400mm (w) x 300mm (h)
5m (w) x 2.8m (h) x 5m (d) Not trussed, to allow flight Ideally 2.8m height, but a height of 2m may be acceptable in some circumstances
At least above 5m abo ground and away from structions and creepe
Preferably integral to building, but where th possible externel, e.g. eaves
ry
ove m obers
the his is not under the
Aspect of Roost
Summer nusery roosts on most southerly side or westerly aspect for solar heating. However, the risk of overheating should be considered. A location that provides a stable microclimate/ regime mmay work better than one that heats up quickly and loses heat quickly
Temperature °C Summer
Winter
30 - 40 °C (day time temperature)
0 - 6 °C
Materials and Other Comments
Rough (for grip), natural materials such as untreated timber, stone or masonary is preferred Not toxic or corrosive and no risk of entanglement Suitable thermal properties (reducing 24-hour fluctuations), but allowing suitable thermal gain for summer roosts
Male roosts and winter hibernatiion roosts on notherly aspect
North facing boxes used for hibernating will benefit from using insulation materials. Larger crevice spaces (particularly in the vertical dimension) can provide a range of temperatures, which will allow the bats to move according to their temperature needs Access not lit by artificial lighting The crevice-roosting provision within the roost to be located on the south or west side for solar heating. or in the most thermally stable condition
30 - 40 °C
0 - 6 °C
Rough (for grip), natural materials such as untreated timber, stone or masonary is preferred Not toxic or corrosive and no risk of entanglement
The location of the flight area is not as important
Suitable thermal properties (reducing 24-hour fluctuations), but allowing suitable thermal gain for summer roosts North facing boxes used for hibernating will benefit from using insulation materials. Larger crevice spaces (particularly in the vertical dimension) can provide a range of temperatures, which will allow the bats to move according to their temperature needs Access not lit by artificial lighting
The crevice-roosting provision within the roost to be located on the south or west side for solar heating. or in the most thermally stable condition
30 - 40 °C
0 - 6 °C
Rough (for grip), natural materials such as untreated timber, stone or masonary is preferred Not toxic or corrosive and no risk of entanglement
The location of the flight area is not as important
Suitable thermal properties (reducing 24-hour fluctuations), but allowing suitable thermal gain for summer roosts North facing boxes used for hibernating will benefit from using insulation materials. Larger crevice spaces (particularly in the vertical dimension) can provide a range of temperatures, which will allow the bats to move according to their temperature needs Access not lit by artificial lighting
The roost is most likely to be in a roof space; this should have an orientation that allows a south-facing solar gain or an L-shape to allow temperature-range choice
30 - 40 °C
6 - 10 °C
Rough (for grip), natural materials such as untreated timber, stone or masonary is preferred Not toxic or corrosive and no risk of entanglement Suitable thermal properties (reducing 24-hour fluctuations), but allowing suitable thermal gain for summer roosts North facing boxes used for hibernating will benefit from using insulation materials. Larger crevice spaces (particularly in the vertical dimension) can provide a range of temperatures, which will allow the bats to move according to their temperature needs Access not lit by artificial lighting
Outline of roosting and nesting preferences for Crevice-dwelling Bats Source: Designing for Biodiversity: A technical Guide for new and existing buildings by K. Gunnell, B. Murphy and Dr. C. Willamas.
Rules and Guidelines for Bat Roost Architecture
99
Rules and Guidelines for Bat Roost Architecture 5. Bat Roost for Crevice-Dwelling Bats
Based on the research, a basic design for a stand alone bat roost for Crevice-dwelling bats was created. This is to illustrate and cover the basic requirements for a structure.
1
Entry point The entry point needs to be at least aboe 2m and following the dimensions of a crevice-dwelling bat access dimensions of ‘20 - 50mm (w) x 15 - 20mm (h)’.
2
Vertical distance for drop The vertical distance drop needs to be 1m or less so that the bats could drop from the access point before finding their balance to fly again.
3
Cavity volume The cavity volume is not mandatory. However, with a cavity volume there is more likely a variation in temperature.
4
Height from ground The entry point and volume has to be at least 2m high. Studies have shown around 2-7m but it could be even higher.
5
Interior slope The interior slop allows for a crawl space and also movement in temperature. Warm temperature travels upwards therefore cooler temperature zones can be applied for areas at the bottom of the slope and warmer temperatures could be applied for the top of the slope.
6
Gravel The placement of gravel at the bottom of the bat roost structure would be helpful for bat monitoring. It is important to avoid directly disturbing the bats and the bat roosts. Only professionals are allowed to handle bats by hand. However, bats leave their droppings outside their roost and bat droppings are one way to identify the species and the size of colony. The gravel allows for the droppings to stay and helps participates easily identify them.
7
Exterior surface with sun exposure If the exterior surface absorbs heat, it would be ideal because it could warm the interior space during colder weather. Bats could withstand cold weather but will always find warm shelter.
100
ooke Park
Warm
Warm ? kg
1m
? kg
1m
3
7
1m
1m
5
2
<1m
<1m
3m
?m
?m
1
3m 4
Cold
Cold
?m
?m
6
?m
?m
Chapter 4: Design Proposal
A simple diagram of the basic bat roost requirements, specifically for crevice-dwelling bats.
Rules and Guidelines for Bat Roost Architecture
101
Chapter 57
Rules and Guidelines for Bat Roost Architecture 6. Playing with the Rules of Architecture
There is in fact more to consider when building a bat roost structure. For example, what is the intention? Bats are protected species and it is true that one can see building a bat roost as a way for wildlife conservation. However, the status of bat species in the UK could be used to play with the rules or architecture and turn something temporary to permanent due to bats’ protected status. The drawing on the right shows three approaches: Playing with the rules of architecture with interior spaces Playing with the rules of architecture with exterior spaces Playing with the rules of architecture with temporary strcutures. Playing with the rules of architecture with interior and exterior spaces are similar because it could change the status of a building. Bats inhabiting a building could mean that the building itself becomes protected. Playing with the rules of architecture with temporary structures could become more of an activist role. For example, to save and protect a woodland area, a garden, or even a public space. In the case of Hooke Park, a planning permission is not required for many small temporary buildings so building something small and “temporary” would allow for a possible ‘Playing with the rules of architecture with temporary structures’ scenario. The process of building a bat roost structure in Hooke Park is shown below:
Typical process for an architectural project
Process for an architectural project in Hooke Park
The diagram above shows the two processes : a typical architectural project process and an architectural project in Hooke Park for bat roost architecture.
102
Playing with the rules of architecture through Interior Spaces
Playing with the rules of architecture through Exterior Spaces
Playing with the Rules of Architecture with Temporary Structures
Three approaches in bat roost architecture. Each of these approaches may have rules and regulations that could be further investigated to find ways in which species can live harmonously with humans.
Rules and Guidelines for Bat Roost Architecture
103
64
Part 3 Beyond Hooke Park 1. Hooke Park as an Initial Site of Exploration 2. Threats to Bat Species 3. Bats and Other â&#x20AC;&#x2DC;Building-reliant Speciesâ&#x20AC;&#x2122; 4. Playing with the Rules of Architecture: Rural vs. Urban 5. Bats in the Urban Context
5.1 Permitted Development (PD) 2012
5.2 Passive House
5.3 Bats and Artificial Lighting
6. Bats in London
6.1 Distribution of Bat Species in London
6.2 Monitoring Bats in London
6.3 Wild West End: An Ecological Initiative in Central London
105
Beyond Hooke Park 1. Hooke Park as an Initial Site of Investigation
Hooke Park sets itself up to be a great initial site study of how bats behave and live with us in architecture. However, the inhabitation of bats in built structures extends beyond woodland areas such as Hooke Park. In fact, according to the book ‘Bats in the Anthropocene: Conservation of Bats in a Changing World’, “bats likely form the most diverse group of mammels remaining in urban areas”. However, “our understanding of how other wildlife, including bats, respond to the complex process of urbanization is still limited. Research conducted to date provides a general indication that many bats may be declining due to urbanization, but an understandnig of the processes driving these patterns are still largely unknown”. Although it is important to note that impacts of urbanization are not always negative and can differ between geographic regions. The key is to better understand how urbanization is changing wildlife around the world combine both the scientific and architectural field to collaborate and to learn more about what can be done to imporve urban biodiversity.
106
The image above shows the cleared area of Hooke Park which identifies are the Hooke Park campus. Bats are known to live in the buildings and forage in the surrounding woodlands.
Beyond Hooke Park
107
Beyond Hooke Park 2. Threats to Bat Species
According to the book â&#x20AC;&#x2DC;Bats in the Anthropocene: Conservation of Bats in a Changing Worldâ&#x20AC;&#x2122;, it mentions that the IUCN assessment states that the global major threats to bat species are: Land use changes (logging, non-timber crops, livestock farming and randing, wood and pulp plantations and fire) Urbanization Hunting and persecution Quarrying General human intrusions Bats are particularly susceptible to these human-induced perturbations of habitats because of their distinct life history. Bats are on the slow side of the slow-fast continuum of life histories. For exam,ple, they reproduce at a low rate and are long-lived animals. Thus, bat populations recover slowly from increased mortality rates. The chart on the right shows the different activities/changes that have varied levels of effect on bat populations. The architectural industry is one of the leading factor that affects these bat populations. Architects contirbute to this problem (maybe more so indirectly) through urbanization and landuse changes as seen in the two diagrams on the bottom right.
108
Other Human Intrusions Invasive Species Pollution Climate Change Quarrying Hunting Urbanization Landuse Changes
Frequency in Speciesâ&#x20AC;&#x2122; Assessment
Landuse Change Livestock farming & Ranching, 3% Fire & Fire suppression, 8%
Non-timber Crops 38%
Urbanization
Wood & Pulp Plantations, 1%
Intentional hunting for bushmeat, medicine, sport, 76%
Roads & Rails, 13%
Residential & Commercial Development, 87%
The diagrams above show events that are affecting bat populations. Source: Bats in the Antrhopocene: Conservation of Bats in a Changing World.
Beyond Hooke Park
109
Beyond Hooke Park 3. Bats and Other ‘Building-Reliant Species’
Before the rise of human built structures, bats have existed in abundant populations in natural habitats such such as woodlands. They were living in the cracks,
1
crevices and woodpecker holes of old trees. There are bats that still live this way today but the numbers are getting smaller and smaller as the landscapes have drastically changed. Not only have areas of woodlands disappeared but bats and other speices such as owls, rely on structures such as old trees. Bats and owls are two example of species that do not build their own homes. They are opportunistic and rely on already built structures. The loss of bats and owls is one part of the problem but it has also created a phenomenon where species have gone to find
2
themselves a home within human built architecture. These species are called now called ‘building-reliant species’. 3 4
5
Bat Roost in Trees Navigational aid
1
Crack in tree
2
3
110
Rotten hole
4
Behind the ivy plant
5
Under the tree bark
1
2
3
4 5
6
Bat Roost in Houses
1
Barge board and roof felt Broken tiles
2
3
4
Eaves
Hanging tiles 5
Porch
6
Cellar
Time
The diagram above shows the changes in roost structure over time from natural landscapes to manmde landscapes.
Beyond Hooke Park
111
Beyond Hooke Park 4. Playing with the Rules of Architecture: Rural vs. Urban
Playing with the rules of architecture to build bat roost architecture can be complicated especially when it very much depends on location. The rules in a rural and urban context may differ. In Hooke Park, the idea to build a temporary structure follows very different rules. Hooke Park is a private woodland and has a special relationship with the forestry commission. Any temporary structure, as long as it is in line with the Forestry commision and the criteria of the Hooke Park warden (Zachery Mollica), the structure can be built. In London, the rules to build temporary structures can feel quite limiting. However, it is important to note that within private properties such as the Bedford Square Campus of the Architectural Association, temporary structures can also be built. However, building temporary structures in public places can be much more challenging as it requires a lot of paperwork and planning permission. Within architectural projects though, it is within the right of the homeowner and the architect to consider the urban wildlife that may rely on built structures. Therefore there is the opportunity to build for the purpose of conservation for both urban wildlife and to further use that as a tool to protect the building that is being designed.
112
Playing with the rules of architecture through Interior Spaces
Playing with the rules of architecture through Exterior Spaces
Playing with the Rules of Architecture with Temporary Structures
Three approaches in bat roost architecture. Each of these approaches may have rules and regulations that could be further investigated to find ways in which species can live harmonously with humans.
Beyond Hooke Park
113
Beyond Hooke Park 5. Bats in the Urban Context
5.1 Permitted Development (PD) 2012
In 2012, a new policy was developed called â&#x20AC;&#x2DC;Permitted Development (PD)â&#x20AC;&#x2122;. Permitted Development (PD) grants rights to enable homeowners to undertake certain types of work without the need to apply for planning permission. There are many innovative opportunities whereby PD rights can bring significant benefits to anyone who wants to undertake a project to improve their existing home or is looking to maximise the potential of a new investment. This implied consent of Permitted Development is granted in the form of General Development Planning Orders (GDPOs) which apply separately to England, Wales, Scotland and Northern Ireland. The emergence of the Permitted Development have both positive and negative outcomes. The right for permitted development means that homeowners are allowed to buildng without planning permission which means that the process in which bats are being surveyed are completely ignored. Permitted development could mean that homeowners will build extensions of a buiding without considering the wellbeing
Permitted development rights for householders
or surrounding environmental and ecological conditions. On a more positive note, without a planning permission could also mean building
Technical Guidance
an extended structure that could cater and accommodate building-reliant species such as bats. The aim is to bring awareness and encourage homeowners to consider the surrounding environmental and ecological well-being of their home.
Ministry of Housing, Communities and
114
Measurement of the extension beyond the rear wall should be made from the base of the rear wall of the original house to the outer edge of the wall of the extension (not including any guttering or barge boards).
The structure of the rules on permitted development The rules on permitted development, set out in Schedule 2 of the Order, are sub-divided into a series of Parts. Part 1 specifically deals with development within the curtilage of a house. Part 1 is then sub-divided into Classes covering various types of development: Class A covers the enlargement, improvement or alterations to a house such as rear or side extensions as well as general alterations such as new windows and doors. There is a neighbour consultation scheme for larger rear extensions under Class A, paragraph A.1(g). Class B covers additions or alterations to roofs which enlarge the house such as loft conversions involving dormer windows.
Measurement of ‘extend beyond a rear wall’ when the extension is directly attached to the rear wall
Front
Rear
Class C covers other alterations to roofs such as re-roofing or the installation of roof lights/windows. Class D covers the erection of a porch outside an external door. Class E covers the provision of buildings and other development within the curtilage of the house. Class F covers the provision of hard surfaces within the curtilage of the house such as driveways. Class G covers the installation, alteration, or replacement of a chimney, flue or soil and vent pipe. Class H covers the installation, alteration, or replacement of microwave antenna such as satellite dishes.
Where a new extension is joined to an existing extension, under paragraph (ja) (see page 28) the limits in (f) or (g) apply to the size of the total enlargement (being the proposed enlargement together with the existing enlargement). The following example, showing a side view of a detached house, would not be permitted development. If a detached house has an existing, single storey, ground floor extension that was not part of the original house, and which extended beyond the rear wall by 4 metres, then it would not be possible to add an additional single storey, ground floor extension of 5 metres without an application for planning permission - because the enlarged part of the house would then extend beyond a rear wall by more than 8 metres (or more than 4 metres on article 2(3) land or sites of special scientific interest).
There are also other Parts of the Order that may be relevant to householders. For example, Part 2 covers matters such as erection or construction of gates, fences and walls, exterior painting, charging points for electric vehicles and CCTVs. Part 14 covers the installation of domestic microgeneration equipment such as solar panels.
Previously added rear extension
When considering whether a development proposal is permitted development, all of the relevant Parts of the Order and all the Classes within those Parts need to be taken into account. For example, Part 1 Class A prevents the installation, alteration or replacement of a chimney, flue or soil and vent pipe from being permitted development because these works are specifically provided for in Class G subject to the rules set out under that Class. Similarly, changes to the roof of a house are not permitted development under Class A, but may be permitted development under Class B or C.
X New extension would not be permitted development
Front Rear
In order to be permitted development, a proposal must meet all the limitations and conditions under each Class relevant to the proposal. It is therefore essential that any proposed household development is considered in the context of the permitted development rules as a whole in order to determine whether it benefits from permitted development rights and therefore does not require an application for planning permission.
4m
5m
8
For example, where a proposed two storey extension at the rear of a house has a roof that joins onto the main roof of the original house, the works will need to meet the requirements of both Class A (which covers the enlargement of the house) and Class C (which covers any alterations to the roof) in order to be permitted development. If the works also include the creation of a dormer window to enlarge the roof space, either in the extension or the original roof space, then they would also need to meet the requirements of Class B.
18
Where the original rear wall of a house is stepped, then each of these walls will form ‘the rear wall of the original dwellinghouse’. In such cases, the limits on extensions apply to any of the rear walls being extended beyond. In the example below showing a plan of a semi-detached house with an original ‘stepped’ rear, each of the extensions (shaded) would meet the requirements for a single storey extension as they do not extend more than 6 metres beyond the rear wall (or more than 3 metres on article 2(3) land or sites of special scientific interest).
Further restrictions on permitted development It is important to note that a local planning authority is allowed to remove permitted development rights in some or all of its area by issuing what is known as an Article 4 Direction; or may have removed those rights on the original, or any subsequent, planning permission for the house. Where permitted development rights have been removed in either of these ways a planning application will be needed for development. Before undertaking any development, checks should be undertaken with the local planning authority to determine whether any such restrictions on permitted development have been made. The remainder of this guidance provides further explanation about the detailed rules covering what improvements can be made to a house and its surroundings as permitted development. In particular, it provides more details on the limits (for example on size) and the conditions that will need to be complied with if development is to take place without the need for an application for planning permission. The guidance covers in detail Classes AE of Part 1 of the Order which cover common development projects such as extensions, loft conversions, alterations to a roof, porches, and buildings on land surrounding the house. The rules for Classes F-H are included in this document for reference but detailed guidance on them is not included, although cross-references are included to other guidance published by the Ministry of Housing, Communities and Local Government.
3m 3m 3m
However, the extension shown below would not meet the requirements for permitted development. In the case of rear wall ‘B’, the extension goes more than 6 metres beyond that rear wall (or on article 2(3) land or sites of special scientific interest the extension to rear walls ‘A’ and ‘B’ is more than 3 metres beyond those walls).
3m
6m
336
9m
X
A B
September 2019 Local Government 19
9
Source: Ministry of Housing, Communities & Local Government. A few pages from the ‘Permitted development rights for householders’ from Ministry of Housing, Communities & Local Government.
Beyond Hooke Park
115
Beyond Hooke Park 5. Bats in the Urban Context
5.2 Passive House
The underlying passive principles were pioneered and formulated in the United States and Canada in the 1970s and 80s. By 1986 the noted physicist William Shurcliff was able to summarize what at the time he considered a mature and widely adopted technology. He described the five main principles of superinsulation also known then as passive housing in his article int the 1986 Energy Reviewâ&#x20AC;?: Thick insulation Airtight construction Prevention of moisture migration into cold regions within the walls, and other regions where much condensation could occur Optimum sizing of window areas Steady supply of fresh air Passive House standards are still considered and used today. But what is considered sustainable and energy efficient in a buiding, does not consider enough the surrounding environmental and ecological conditions. An airtight construction means that it is very well sealed and that heat loss would be minimal. This kind of design approach would mean that there would be less opportunity for bats to find roost in buildings. In fact, there are many parts of a passive house that could contribute to the accomdation of emerging building-reliant species if only they were considered more during the design process. So the question is, how can we build energy efficient buildings whilst accommodating building-reliant species such as bats?
116
Source: Passive House Institute. A self-contained passive house works for human conditions but does not consider the surrounding environmental and ecological conditions
Beyond Hooke Park
117
Beyond Hooke Park 5. Bats in the Urban Context
5.3 Bats and Artificial Lighting
According to the Bat Conservation Trust, studies have estimated that in 2016 more than 80% of the world population and more than 99% of the U.S. and European population live under light-polluted skies. Worldwide this is up from 66% in 2001, or an increase of more than 14%; ‘light-polluted skies’ are defined as being about 10% higher than normal night sky brightness levels. This means that only about a fifth of England now has ‘pristine night skies’ – that is skies ‘completely free from light pollution’. Concerns about the impacts of this have been expressed for a long time, both in reference to human and ecosystem health. For bats, artificial lighting is thought to increase the chances of predation, and therefore bats may modify their behaviour to respond to this threat. Many avian predators will hunt bats which may be one reason why bats avoid flying in the day. When we refer to artificial lighting we are referring to a number of different characteristics and types, all of which have varying impacts. For example, different types of luminaire emit a different spectrum of light. The spectrum of light runs from short wave (ultraviolet) to long wave (infrared), and can vary in intensity (potentially causing glare) and illuminance (measured in lux). It is important to remember that there is no legislation requiring an area or road to be lit. The building regulations for domestic buildings specify that 150 watts is the maximum for exterior lighting of buildings but this does not apply to private individuals who install their own lighting.
Source: Bat Conservation Trust. A document on bats and rtifical Lighting in the UK.
118
Source: Bat Conservation Trust. Top: A diagram of light zones in the urban context. Bottom: An example of physical light screening option.
Beyond Hooke Park
119
Beyond Hooke Park 6. Bats in London
6.1 Distribution of Bat Species in London
The map of the right is the Bat Atlas of London created by the London by group in 2010. The London Bat Group together with Green Information for Greater London (GiGL ) team mapped different time periods, record type (roost, flight, etc) and species distribution in London. The map on the right shows the distribution of all bat species. The maps on the following page shows the distribution of bats based on each of the twelve known species that currently exist in London. Visualising the bat records in this way has allowed understanding on how bats are using London’s urban landscape. Already the atlas has shown a few interesting trends. For example: Serotine bat seems to be concentrated to the south of London. Leisler’s bat roosts appear to be highly localised. Rare bat species (such as barbastelle & Bechstein’s bat) have not been recorded in London for many years. The London Bat Group hopes to use ‘The Bat Atlas of London’ to galvanise support for bat conservation in the capital. Copies have been sent to all London authority planning departments in hopes to use the atlas to direct survey effort to areas of London where there are gaps in our knowledge of bat distribution and status.
120
N
Source: GiGL (Green Information for Greater London). Distribution of all bat populations in London.
Beyond Hooke Park
121
Beyond Hooke Park 6. Bats in London
122
6.1 Distribution of Bat Species in London
1
Common pipistrelle
2
Daubentonâ&#x20AC;&#x2122;s bat
3
Kuhlâ&#x20AC;&#x2122;s pipistrelle
4
Lesser Noctule
5
Long-eared bats
6
Nathusius’ pipistrelle
11
Soprano pipistrelle
7
Natterer’s bat
12
Whiskered/Brandt’s bat
8
Noctule
9
Parti-coloured bat
10
Serotine
Source: GiGL (Green Information for Greater London). Distribution of bat populations based on bat species in London.
Beyond Hooke Park
123
Beyond Hooke Park 6. Bats in London
6.2 Monitoring Bats in London
There are many local groups that do monitoring and conservation work for bats, and this is for both rural and urban environments. In London, for example, there is the London Bat Group (which is a part of the Bat Conservation Trust). The London Bat Group aims toâ&#x20AC;? Protect and conserve bats, their roosts, feeding areas and hibernation sites in Greater London. Provide information on bats to the public Monitor bat populations and distributions Maintain a pool of licensed volunteer bat workers who can visit roost sites and provide expert assistance on matters relating to bats in Greater London. The map on the right are suggested sites for bat sightings from the London Bat Group.
A few photos of London Bat Group volunteers doing monitoring and conservation work. Source: London Bat Group.
124
A map of bat sighting sites in Greater London provided by the London Bat Group. Source: London Bat Group.
Beyond Hooke Park
125
Beyond Hooke Park 6. Bats in London
6.2 Monitoring Bats in London
Nature Smart Cities is another project that has been conducted, specifically in Queen Elizabeth Olympic Park. It is a project that is in partners with University College London (UCL), Intel, Bat Conservation Trust (BCT), London Wildlife Trust (LWT), and ARUP. It brings together environmental researchers and technologists to develop the world’s first end-to-end open source system for monitoring bats, to be deployed and tested on site. The known bat species they have found in Queen Elizabeth Olympic Park are: the Common pipistrelle, Soprano pipistrelle, Noctule, Leislers bat, Nathusius’ pipistrelle, Brown long-eared bat, Grey long-eared bat, Brandt’s bat, Daubenton’s bat and the Natterer’s bat. Of these species, the Grey long-eared bat is considered to be a very rare species in the UK. The image on the top left shows the device which is used to record bats in the park. The bottom left image shows the recorded data of from the device. This particular recording was from sensor number 7. The map on the right shows the distribution of sensors around Queen Elizabeth Olympic Park and the bat calls detected.
Top: A photo of the device used to collect bat calls. Bottom: Bat calls detected from sensor 7. Source: Nature Smart Cities.
126
Sensor 7
A map of bat sensors in Queen Elizabeth Olympic Park, East London. Source: Nature Smart Cities.
Beyond Hooke Park
127
Beyond Hooke Park 6. Bats in London
6.3 Wild West End: An Ecological Initiative in Central London
Looking closely at Central London, there is an known ecological initiative that is currently active known as the ‘Wild West End’. The monitoring program began in 2016 and occurs every two years to monitor target species and installed and enhanced features. The monitoring process aims to replicate the surveys carried out in 2016 to ensure that data is comparable to the baseline and enable progress to be tracked. Bats are monitored using remote echolocation devices to record the level of bat activity in the area, the species present, and the types of activity. Each device is left in-situ for one week during the late April to early June period – the peak time for seasonal activity. The findings were that in total, four species of bats were identified during the 2018 surveys: common and soprano pipistrelle, noctule, and serotine. High levels of activity were recorded at various locations including St James’s, Marylebone and Piccadilly. The results were indicative of there being roosts within the West End. New species was recorded in the Wild West End in 2018; the serotine. This species is rarely recorded in central London. Moths are an important dietary component for this species, which is known to favour foraging within mature woodlands and parks with large trees. The continued planting of a variety of habitats, management of exiting mature trees and garden squares, and planting of new trees which are intended to live a long time may create the right conditions to further encourage this species to forage in central London. An important point to note is that Bedford Square falls within the boundaries of the monitoring program due to the proximity of Bedford Square gardens so it could be benefitial for the Architectural Association to contribute to these studies.
128
Bedford Square: No Data
Location of bat box Location of pipistrelle pipistrelle
An interactive map on the Wild West End Website showing the area of green spaces covered, the location of bat sightings and the location of bat boxes.
Beyond Hooke Park
129
Beyond Hooke Park 6. Bats in London
130
6.3 Wild West End: An Ecological Initiative in Central London
Source: Wild West End Website. Wild West Endâ&#x20AC;&#x2122;s criteria for green spaces. Each green spac needs to fulfil two of the four categories .
Beyond Hooke Park
131
132
Part 4 Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 1. Considerations for Bat Roost Architecture in New and Existing Buildings of London 2. Interventions in an Existing Building: The Architectural Association, Bedford Square
2.1 Solar Analysis of Building Volume
2.2 The Two Interventions: Barrel Vault and 34 Bedford Sqaure
2.3 Barrel Vault
2.3.1 Temperature and Heat Flux Study
2.3.2 Bat Roost Design
2.3.3 Temperature and Heat Flux Study for Design
2.4 34 Bedford Square
2.4.1 Temperature and Heat Flux Study
2.4.2 Bat Roost Design
2.4.3 Temperature and Heat Flux Study for Design
3. Intervention in New Building: A Residential Project at Farncombe Street
3.1 Solar Analysis of Building Volume
3.2 The Area of Intervention Within Building
3.2.1 Temperature and Heat Flux Study
3.2.2 Bat Roost Design 1
3.2.3 Temperature and Heat Flux Study for Design 1
3.2.4 Bat Roost Design 2
3.2.5 Temperature and Heat Flux Study for Design 2
133
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 1. Considerations for New and Existing Buidlings in London
The annual temperature graph shown on the right illustrates the temperature range annually in London. In comparison to the weather data for Hooke Park as shown in Part 2 of this document, London is generally warmer in the summer and has longer warm days than Southewest of the UK. The average temperature range within that area ranges from 1 째C (coldest in February) to 30 째C (warmest in August). The warm season lasts for 3 months, from June 15 to September 17 and the The cool season lasts for 4 months, from November 22 to March 24. According to the Bat Roost Preferences for UK bat species, most crevice-dwelling bats can withstand the coldest temperature in this area. However, bats that need flight space and flying access to their roosts (particularly horseshoe bats) might find the winters too cold as their winter roost temperature range is 6 째C - 10 째C. In the following studies, this weather data will be used to test the sun exposure on the structural volumes and also for the temperature variation and heat flux on the structure.
134
Source: EnergyPlus Weather Data.
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
135
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 1. Considerations of Bat Roost Architecture in New and Existing Buidlings of London
The map on the right highlights all the green areas within London. This map shows a variation of green spaces: allotment areas, conservation areas, park and commons, miscellanous green space, water and wetland, and woodland. Unlike bats that live in rural areas, bats that live in urban areas might choose more so to live in built structures rather than trees. Built structures are likely to offer more warmth and protected shelter particularly in the urban environment where trees (old trees) are scarce. In this map, there are also two points indicated where a more detailed study will be conducted: The Architectural Association, Bedford Square 1 The buildings of the Architectural Association will be a part of the study to see how a bat roost could be incorporated into the building. There will be two studies one of which is an intervention on the roof of the 34 Bedford Square (Georgian building) and the other intervention is the roof of the Barrell Vault (which has existed since the 1950s). 2
A Residential Project, Farncombe Street
The Farncombe Street project is an ongoing project shared to be by Giles Bruce, a Technical Studies tutor at the AA. The aim is to look at building design aimed for energy efficiency and see how a slight tweek in design in a contemporary building could provide an opportunity for bats to roost in Central London.
136
1
Bedford Square
2
Farncombe Street
N
A map showing the green spaces of London and two points indicating two buildings for further study. Source: Green Information for Greater London (GiGL)
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
137
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 2. Intervention in Existing Building: The Architectural Association, Bedford Square
The Architectural Association (32-39 Bedford Square) sits within Central London and is situated next to a private and protected piece of green space, Bedford Square Gardens. Bats are known to exist within central London although so far from the known natural landscapes of bats such as the woodlands, they roost within the buildings and are connected by the green spaces of the city where they forage. The buildings that make up the Architectural Association are old Georgian buildings that are about 20m in height or more. The height is ideal for bats and more importantly, an old building where there could be nooks and cracks are the ideal places for bats to roost. The building itself is also situated within the boundaries of the Wild West End Project, which has proved that there are bats that exist within this area. It is possible and benefitial to contribute to the Wild West End ecological initiative so that the urban biodiversity could continue to coexist with humans in the urban context. The following page illustrates 32-39 Bedford Square and its sun exposure in the winter month of January (top row) and the summer month of June (bottom row).
138
The Architectural Association, Bedford Square
0m
20m
N
An aerial view of the Architectural Association, Bedford Square. Source: Google Earth.
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
139
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 2. Intervention in Existing Building: The Architectural Association, Bedford Square
2.1 Solar Analysis of Building Volume
Tested Volume (Southeast View)
Bedford Square in January (Top View)
Surrounded by similar Georgian buildings
Sunlight Hours: 9am-3pm
and a few tall buildings in the West.
Bedford Square in June (Top View) Sunlight Hours: 9am-3pm
140
Bedford Square in January (Southwest View) Sunlight Hours: 9am-3pm
Bedford Square in June (Southwest View) Sunlight Hours: 9am-3pm
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
141
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 2. Intervention in Existing Building: The Architectural Association, Bedford Square
2.2 The Two Interventions: Barrel Vault and 34 Bedford Square
1
Barrel Vault, Bedford Square
2
34 Bedford Square
142
1
Potential Bat Roost
2
Potential Bat Roost
The Third Floor Plan of the Architectural Association. Source: The Archive of the Architectural Association.
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
143
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 2. Intervention in Existing Building: The Architectural Association, Bedford Square
2.2 The Two Interventions: Barrel Vault and 34 Bedford Square
1
Barrell Vault, Bedford Square
2
34 Bedford Square
144
1
Potential Bat Roost
2
Potential Bat Roost
The Roof Plan of the Architectural Association. Source: The Archive of the Architectural Association.
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
145
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 2. Intervention in Existing Building: The Architectural Association, Bedford Square
2.2 The Two Interventions: Barrel Vault and 34 Bedford Square
1
Barrell Vault, Bedford Square
2
34 Bedford Square
1
146
2
Section drawing indicating the interested area within the Architectural Association. Source: The Archive of the Architectural Association.
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
147
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 2. Intervention in Existing Building: The Architectural Association, Bedford Square
2.2 The Two Interventions: Barrel Vault and 34 Bedford Square
100cm 91cm
364cm 239cm
184cm 79cm
1
1
6 2
2 3 3 5
5
4
4
5
Detailed roof section of the Barrel Vault, Bedford Square
1
Corrogated metal roof sheet Timber beam
2
Slate Roof Tile
1
4
Insulation
3
Dry wall
Interior space
Timber beam
2
Insulation
3
5
Detailed roof section of 34 Bedford Square
4
5
Dry wall
Interior space 6
Window
Top: Volume and dimensions of the two intervention area. Bottom: Section drawing of the two intervention area marking the material that will be used for the temperature and heat flux study.
148
1456cm
1641cm
6011cm
3302cm
A perspective model indicating the volume and dimension of intervention area in relation to the rest of the building.
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
149
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 2. Intervention in Existing Building: The Architectural Association, Bedford Square
2.3 Barrel Vault
2.3.1 Temperature and Heat Flux Study
150
Barrel Vault (Existing) Temperature Variation
Barrel Vault (Existing) Heat Flux
Exterior temperature (winter): 1 oC Interior temperature: 21 oC
Exterior temperature (winter): 1 oC Interior temperature: 21 oC
Barrel Vault (Existing) Temperature Variation
Barrel Vault (Existing) Heat Flux
Exterior temperature (Summer): 30 oC Interior temperature: 21 oC
Exterior temperature (Summer): 30 oC Interior temperature: 21 oC
Left to Right: Temperature variation in January; Heat flux in January; Temperature variation in June; Heat flux in June.
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
151
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 2. Intervention in Existing Building: The Architectural Association, Bedford Square
2.3 Barrel Vault
2.3.1 Bat Roost Design
1
5
2
3 5
4
6
Detailed roof section of the Barrel Vault, Bedford Square Metal roof sheet
1
Timber beam
2
Insulation
3
4
5
Interior space 6
152
Dry wall Window
1
2 5
3
91cm
3cm
2
2
1 2
4
79cm 3
4 6
5
3
A section drawing of a bat roost design, illustrating thechanges made from the existing building (shown on the left).
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
153
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 2. Intervention in Existing Building: The Architectural Association, Bedford Square
2.3 Barrel Vault
2.3.1 Temperature and Heat Flux Study for Design
1
2
Barrel Vault (Design) Temperature Variation
Barrel Vault (Design) Heat Flux
Exterior temperature (winter): 1 oC Interior temperature: 21 oC
Exterior temperature (winter): 1 oC Interior temperature: 21 oC
Changes in temperature variation and heat flux with design intervention: The changes made in this design were the addition of a dry wall to separate the space between the office and the bat roost. The final result showed that (even without any insulation on that additional dry wall, the bat roost will still experience warm temperatures of about 16 oC. Without the insulation, heat can travel through the dry wall and accommodate a warm space for bat colonies as shown in
1
.By
creating an extended opening, it allows for bats to have a vertical distance to drop 2 3 before their flight (which is common bat behavior). However, in and ,
it shows that the for this opening is a metal sheet and there is a void close to the opening. This allows for a lot of air movement which could help regulate the temperature within the interior space.
154
3
Barrel Vault (Design) Temperature Variation
Barrel Vault (Design) Heat Flux
Exterior temperature (Summer): 30 oC Interior temperature: 21 oC
Exterior temperature (Summer): 30 oC Interior temperature: 21 oC
Left to Right: Temperature variation in January; Heat flux in January; Temperature variation in June; Heat flux in June.
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
155
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 2. Intervention in Existing Building: The Architectural Association, Bedford Square
2.3 34 Bedford Square
156
2.3.1 Temperature and Heat Flux Study
34 Bedford Sqaure (Existing) Temperature Variation
34 Bedford Sqaure (Existing) Heat Flux
Exterior temperature (winter): 1 oC Interior temperature: 21 oC
Exterior temperature (winter): 1 oC Interior temperature: 21 oC
34 Bedford Sqaure (Existing) Temperature Variation
34 Bedford Sqaure (Existing) Heat Flux
Exterior temperature (Summer): 30 oC Interior temperature: 21 oC
Exterior temperature (Summer): 30 oC Interior temperature: 21 oC
Left to Right: Temperature variation in January; Heat flux in January; Temperature variation in June; Heat flux in June.
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
157
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 2. Intervention in Existing Building: The Architectural Association, Bedford Square
2.3 34 Bedford Square
2.3.1 Bat Roost Design
1
6 2
3
4
5
Detailed roof section of 34 Bedford Square Slate Roof Tile
1
Timber beam
2
Insulation
3
4
5
158
Dry wall
Interior space 6
Window
7
Plywood
1
7
3cm
3cm
100cm 6
2
4
184cm 3
3
5
A section drawing of a bat roost design, illustrating thechanges made from the existing building (shown on the left).
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
159
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 2. Intervention in Existing Building: The Architectural Association, Bedford Square
2.3 34 Bedford Square
2.3.1 Temperature and Heat Flux Study for Design
1
2
34 Bedford Sqaure (Design) Temperature Variation
34 Bedford Sqaure (Design) Heat Flux
Exterior temperature (winter): 1 oC Interior temperature: 21 oC
Exterior temperature (winter): 1 oC Interior temperature: 21 oC
Changes in temperature variation and heat flux with design intervention: The fluctuations in the temperature seem very high in the roof void. However, it does show that even in the winter, the interior temperature could reach up to 12 oC due to the heat travelling upwards from the top floor. The heat then travels up to the vertical planks where warm air could get trapped
1
. However, in the summer,
bats may find roosting in the lower parts of the planks more comfortable as it may be cool in temperature. The heat flux shows that in winter the movement of heat is very high, due to the heat coming from the top floor space, heat escapes the dry wall of the ceiling and into the roof void. The movement is much slower once it reaches within the planks
2
, which is ideal for bats if the warm temperature
accumulates there in the winter.
160
34 Bedford Sqaure (Design) Temperature Variation
34 Bedford Sqaure (Design) Heat Flux
Exterior temperature (Summer): 30 oC Interior temperature: 21 oC
Exterior temperature (Summer): 30 oC Interior temperature: 21 oC
Left to Right: Temperature variation in January; Heat flux in January; Temperature variation in June; Heat flux in June.
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
161
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 3. Intervention in New Building: A Residential Project at Farncombe Street
The Farncombe Street residential project is located in South London right by the River Thames. The site is surrounded by a mix of new and old buildings, most of which are about two floors in height. The taller buildings are located North of the site and for a part of this project, the building design was to build in height for a viewing tower without disrupting the other surrounding buildings. The site is surrouded by rows of trees and small patches of greenery but the closest park to the Farncombe project is Kings Stairs Gardens and Southwark Park, located East of the site. It would mostly likely be that bats venture and forage those parks and find roosting areas in nearby homes.
162
Residential Project, Farncombe Street
0m
20m
N
An aerial view of the residential project at Farncombe Street Source: Google Earth.
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
163
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 3. Intervention in New Building: Farncombe Street
3.1 Solar Analysis of Building Volume
Tested Volume (Southwest View)
Farncombe Street in January (Top View)
Surrounded by similar height buildings
Sunlight Hours: 9am-3pm
and a few tall buildings in the North.
Farncombe Street in June (Top View) Sunlight Hours: 9am-3pm
164
Farncombe Street in January (Southwest View) Sunlight Hours: 9am-3pm
Farncombe Street in June (Southwest View) Sunlight Hours: 9am-3pm
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
165
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 3. Intervention in New Building: Farncombe Street
3.2 The Area of Intervention Within Building
Third Floor Plan of the Farncombe Project Source: Giles Bruce, Technical Studies Tutor.
166
Section Drawing of the Farncombe Project. Source: Giles Bruce, Technical Studies Tutor.
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
167
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 3. Intervention in New Building: Farncombe Street
3.2 The Area of Intervention Within Building
1400cm 139cm 99cm
7
2
5
3
1
2
3 4
6
7
Detailed roof section of the Farncome Street Project Fibre cemet Slate
1
Insulation
2
3
7
Timber Steel beam
4
5
Dry wall
6
Window
Interior space
Top: Volume and dimensions of the intervention area. Bottom: Section drawing of the intervention area marking the material that will be used for the temperature and heat flux study.
168
1400cm 1245cm
139cm
99cm
846cm
1020cm
A perspective model indicating the volume and dimension of intervention area in relation to the rest of the building.
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
169
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 3. Intervention in New Building: Farncombe Street
3.2 The Area of Intervention Within Building
170
3.2.1 Temperature and Heat Flux Study
Farncombe Street (Existing) Temperature Variation
Farncombe Street (Existing) Heat Flux
Exterior temperature (winter): 1 oC Interior temperature: 21 oC
Exterior temperature (winter): 1 oC Interior temperature: 21 oC
Farncombe Street (Existing) Temperature Variation
Farncombe Street (Existing) Heat Flux
Exterior temperature (Summer): 30 oC Interior temperature: 21 oC
Exterior temperature (Summer): 30 oC Interior temperature: 21 oC
Left to Right: Temperature variation in January; Heat flux in January; Temperature variation in June; Heat flux in June.
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
171
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 3. Intervention in New Building: Farncombe Street
3.2 The Area of Intervention Within Building
3.2.2 Bat Roost Design 1
7
2
5
3
1
2
3 4
6
7
Detailed roof section of the Farncome Street Project Fibre cemet Slate
1
Insulation
2
Timber
3
Steel beam
4
7
5
Dry wall
6
Window
Interior space 8
9
172
Slate Plywood
5
2
3
7
5
139cm 1
8
3cm
4
99cm
4
5
6
7
A section drawing of a bat roost design, illustrating thechanges made from the existing building (shown on the left).
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
173
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 3. Intervention in New Building: Farncombe Street
3.2 The Area of Intervention Within Building
3.2.3 Temperature and Heat Flux Study for Design 1
1
Farncombe Street (Design 1) Temperature Variation
Farncombe Street (Design 1) Heat Flux
Exterior temperature (winter): 1 oC Interior temperature: 21 oC
Exterior temperature (winter): 1 oC Interior temperature: 21 oC
Changes in temperature variation and heat flux with design intervention: The intervention in design 1 shows that the temperature variation and heat flus is relatively similar to the existing structure since there are not many changes within the void. However, a access tunnel was added as a part of the design and it shows that temperature can escape through the tunnel in the winter but the warm temperatures may find they way in since the interior building temperature is much cooler than the outside summer heat. The heat flux in the winter shows that there is a lot of heat movment in the tunnel
1
and mild movement in the surrounding
2 void. However, in the summer , the heat flux diagram shows that the heat move-
ment is minimal a part from the heat movement in the access tunnel.
174
2
Farncombe Street (Design 1) Temperature Variation
Farncombe Street (Design 1) Heat Flux
Exterior temperature (Summer): 30 oC Interior temperature: 21 oC
Exterior temperature (Summer): 30 oC Interior temperature: 21 oC
Left to Right: Temperature variation in January; Heat flux in January; Temperature variation in June; Heat flux in June.
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
175
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 3. Intervention in New Building: Farncombe Street
3.2 The Area of Intervention Within Building
3.2.4 Bat Roost Design 2
7
2
5
3
1
2
3 4
6
7
Detailed roof section of the Farncome Street Project Fibre cemet Slate
1
Insulation
2
Timber
3
Steel beam
4
7
5
Dry wall
6
Window
Interior space 8
9
176
Slate Plywood
5
2
3
7
5
139cm 1
9 8
3cm
4
99cm
4
5
6
7
A section drawing of a bat roost design, illustrating thechanges made from the existing building (shown on the left).
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
177
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context 3. Intervention in New Building: Farncombe Street
3.2 The Area of Intervention Within Building
3.2.5 Temperature and Heat Flux Study for Design 2
1
2
Farncombe Street (Design 2) Temperature Variation
Farncombe Street (Design 2) Heat Flux
Exterior temperature (winter): 1 oC Interior temperature: 21 oC
Exterior temperature (winter): 1 oC Interior temperature: 21 oC
Changes in temperature variation and heat flux with design intervention: Design 2 shows an additional intervention from Design 1. Slanted wooden planks were added in the interior so that it could divert the temperature movement and create more roosting spaces (bats require surfaces in which they can cling onto with their feet). The temperature variation study shows that with these additional wooden planks, it created a small area
1
that can accumulate the heat during the
winter time and the heat flux diagram also shows that there are not a lot of heat movement in that same area
2
. Bats can also choose more cooler temperatures
when bats choose to roost on the wooden planks closer to the access tunnel. The temperature variation in the summer doesnâ&#x20AC;&#x2122;t fluctuate that much but the roost.
178
Farncombe Street (Design 2) Temperature Variation
Farncombe Street (Design 2) Heat Flux
Exterior temperature (Summer): 30 oC Interior temperature: 21 oC
Exterior temperature (Summer): 30 oC Interior temperature: 21 oC
Left to Right: Temperature variation in January; Heat flux in January; Temperature variation in June; Heat flux in June.
Application of Rules and Guidelines for Bat Roost Architecture in the Urban Context
179
180
Contacts
Christopher Sadd Hooke Park Forester Danielle Linton Bat researcher, Department of Zoology, University of Oxford Elisa Dierickx Programme Development Manager (Eurasia) of Fauna & Flora International Nigel Fisher Conservator of Wytham Woods, University of Oxford Nick Tomlinson Principal Ecologist of Nick Tomlinson Ecology Sheila Dyason Dorset Bat Group Stephan Hales Wildlife Expert Zachary Joseph Mollica Hooke Park Warden
181
182
References
Bats and Artificial Lighting in the UK: Bats and the Built Environment Series. Bat Conservation Trust. 2018. Print. Bats and Buildings. Bat Conservation Trust (BCT). 2015. Print. Bats in Traditional Buildings. English Heritage, National Trust and Natural England. 2009. Print. Christian C. Voigt, Tigga Kingston. Bats in the Anthropocene: Conservation of Bats in a Changing World. Springers. 2016. Print. Commissioned Report No. 160. A review of the success of bat boxes in houses. Bat Conservation Trust & Scottish Natural Heritage. 2006. Print. Dorset Bat Group: Bat Distribution in Dorset. Dorset Bat Group & Dorset Wildlife Trust. 2019. Print. Dorset Bat Group: Bat Information Leaflet 1 & 2. Dorset Bat Group & Dorset Wildlife Trust. 2019. Print. Garland, L., Wells, M., Markham. S. Performance of maternity bat roost structures near Bath, UK. Conservation Evidence 14, 44-45. 2017. Print. Gunnell, K., Grant, G., Williams, C. Landscape and urban Design for bats and biodiversity. Bat Conservation Trust (BCT). 2012. Print. Gunnell, K., Murphy, B., Williams, Dr. C. Designing for Biodiversity: A Technical Guide for new and existing buildings (Second Edition). RIBA Publishing & Bat Conservation Trust. 2013. Nature-Smart Cities: Urban Bat Life. 2018. https://naturesmartcities.com/. Webpage. Passive House Institute: About Passive House. 2015. https://passivehouse. com/02_informations/01_whatisapassivehouse/01_whatisapassivehouse.htm. Webpage. Tree, I. Wilding: The Return of Nature to a British Farm. Picador. 2019. Print. Tuttle, M., Kiser, M., Kiser, S. The Bat House Builderâ&#x20AC;&#x2122;s Handbook. Bat Conservation International. 2013. Print. Wild West End. 2017. http://www.wildwestend.london/about. Webpage.
183