Biodiversity Net Gain - In this issue - Bulletin of the Chartered Institute of Ecology and Environmental Management - CIEEM
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Bulletin of the Chartered
Institute of Ecology
and Environmental
Management
Issue 104 | June 2019
Biodiversity
Net Gain
In this issue
Biodiversity Net Gain – Better Biodiversity Biodiversity Net Gain –
Opportunity and Challenge Accounting A Scottish Perspective
Feature Article: The Swift – A Bird
You Need to Help!
Figure 1. Swifts are a familiar sight above the rooftops of our villages, towns and cities. Photo credit RSPB-Images.
The Swift – A Bird
You Need to Help! Keywords: biodiversity, conservation,
John Day MCIEEM, Edward Mayer, Dick Newell developments, nestbrick, swift, urban
The Government’s ambitious buildings. They return to the same nest many traditional sites disappear each
every year, establishing colonies that can year through renovation, insulation and
house building programme demolition, while new buildings exclude
last for centuries. They eat flying insects
needs to be carried out in a including aphids, gnats, mosquitoes, flea them from the spaces they normally use.
way that protects and benefits beetles, moths, hoverflies and flying ants
Public perceptions
as well as spiders floating in the air, and
all those species impacted by A recent MSc study investigated
they spend most of their life on the wing.
development. One bird directly (Figure 1) householder attitudes toward nest and
in the line of fire is the swift roost bricks in houses. It questioned 142
Despite a rapid 53% decline between
people of whom 75% thought integral
Apus apus, with a reduction in 1995 and 2016 (Breeding Bird Survey –
swift bricks were a good thing (Roberts
BBS, Harris et al. 2018), the swift is only
suitable nest sites resulting in amber-listed as a Bird of Conservation
2017). Overall, 85% of respondents said
declining numbers across the their decision to buy a house is unlikely to
Concern (BoCC) (Eaton et al. 2015). This
be negatively influenced by the presence of
country. This article reviews the decline is greater than the ‘50% in 25
an integral swift brick while the remaining
years’ threshold required for a species to be
worrying conservation status of 15% thought it might even increase their
placed on the BoCC red list. Therefore, the
likelihood of buying a property. When
the swift, the growing public swift may well move from the amber to red
asked, 73% of people would recommend
interest and the urgent action list at the next BoCC revision in 2021. In
a house with an integral swift brick to a
addition, according to International Union
needed to prevent further losses friend; the remainder didn’t know, and
for Conservation of Nature (IUCN) criteria nobody said they wouldn’t. The study found
by providing suitable nest sites the swift is classified as endangered in the there were no discernible differences in the
in new developments. UK (Stanbury et al. 2017). perceptions of people of different wealth
The causes of decline may include a (using the number of bedrooms as a proxy),
Introduction lack of insect food, but nest site loss age, gender or whether there were children
The swift is a summer visitor, arriving back is a particular problem and is an issue in the house. Studies like this will help to
in the UK to nest in the eaves of houses, we can start to address. Swifts rely on allay concerns of developers that nesting
commercial buildings, churches and older nest sites in buildings but unfortunately birds compromise the saleability of houses.
38 Issue 104 | June 2019
Figure 2. An example of a Manthorpe brick. Figure 3. Cross section of Cambridge Brick system. Photo credit Dick Newell.
Photo credit John Day.
Nest provision range from £25 to £160 or more. It is house sparrows are also declining and will
Great advances have been made in the UK preferable to choose a product compatible benefit from artificial nest sites, there is
over the last decade in our understanding with UK brick sizes; many imported the potential for conflict with homeowners
of swift nest requirements, both for the products are not. There are cement-based because starlings often leave droppings.
protection of existing nests and provision products, for example the CJ Cambridge Starlings can also displace swifts from a
of new nests. Options are now available System and Schwegler, as well as products nest site, but they can be excluded by
for most situations, either ‘off-the-shelf’ made of lighter materials including ensuring nest entrance holes are no larger
or bespoke. Provision of artificial nest sites plastic, for example from Manthorpe and than 65 x 28 mm. It is best to consider
has secured or created many local swift Birdbrickhouses (see Newell 2019b or visit providing external starling boxes on trees
colonies both in the UK and in Europe. https://www.nhbs.com/equipment) adjacent to open areas of grassland where
(Figures 2, 3). they can easily find their insect food.
Swift boxes can be mounted externally
Other species are known to use swift House sparrows and tits will happily use
or fitted internally, either flush with an
bricks, including starlings Sturnus vulgaris, swift bricks (Figure 4) as well as sparrow
external wall or inside a roof space.
house sparrows Passer domesticus, great bricks or external sparrow terraces, which
Externally mounted nest boxes can more
tits Parus major and blue tits Cyanistes swifts cannot use. Sparrows and tits will
easily be fitted to existing buildings but
caeruleus. Whilst numbers of starlings and not generally exclude swifts from a nest
it can also be cost effective to retrofit
integral swift bricks. These are more
secure and eliminate future maintenance
requirements. Details and case studies of
these techniques appear on the Action for
Swifts and the Swift Conservation websites
(see Further Resources below).
For new houses, be it one, several hundred
units or a small two-storey extension,
internal swift bricks are the preferred
option. They leave a neat, tidy finish, last
the lifetime of the building and require no
maintenance (Figure 2). An integral swift
brick is a self-contained unit and prevents
access to anywhere else in the roof space.
It has been around 30 years since the
ornithologist Chris Mead worked with
Schwegler to design integral swift bricks.
Since then many companies have joined
the market. An impartial booklet, Facts
about Swift Bricks (Newell 2019a),
listing many brands and suppliers can be
downloaded from the Action for Swifts Figure 4. House sparrows also use swift nest bricks and can attract swifts to nest.
website (tinyurl.com/swiftbricks). Unit costs Photo credit John Day.
Issue 104 | June 2019 39
Feature Article: The Swift – A Bird
You Need to Help! (contd)
site, and their presence in a swift brick may shade-casting eaves. However, nest boxes Mapping for swifts
even attract prospecting swifts to use that exposed to the sun need to be constructed There are several local or county-level
nest site in future years. Therefore, other of thick enough material and possibly recording systems for swifts. Currently,
species can be accommodated by providing painted white to prevent overheating. two systems operate across the whole of
more swift bricks in a building without Avoid locating nest boxes and bricks above the UK: the RSPB Swift Survey and the
this being detrimental to swifts. However, doors and windows. There is no upper Swift Mapper phone app. Data from these
provision of suitable cover in the form of limit for the height of a swift nest but systems can be used by local authority
hedges and large shrubs in the vicinity of nest boxes installed 5 m or more from the planners, architects, ecologists and
the nest boxes is of equal importance to ground should lead to higher occupancy developers to identify swift hotspots. This
house sparrows.
rates. Ensure a clear flyway of at least should enable adequate mitigation to be
How many swift bricks? 5 m in front of the nest box avoiding incorporated into development projects
And where? obstructions such as trees, including any to protect breeding swifts and to provide
trees planted in new landscaping that may swift nest sites as part of building works.
As swifts and sparrows nest in groups, nest
cause obstruction when mature (Newell The RSPB Swift Survey was created to
bricks should be clustered in suitable areas
of the development, two to four bricks 2019b) (Figure 5a,b). collect data on nesting swifts from the
per dwelling, resulting in an equal number Swifts are long-lived birds and may take public. It allows users to enter or search
overall of nest sites and residential units several years to find a new nest site. for records of swift nest sites or parties of
(Gunnel et al. 2013). On larger commercial Playing recordings of swift calls can ‘screaming’ swifts in flight and provides
buildings, one swift brick per 6 m2 of wall, encourage swifts to investigate a site details about the nest sites. It also allows
mounted near the roof, in clusters of three and accelerate the process. Advice on the absence of swifts to be recorded from
or more, is recommended (Figure 5a,b). this well-proven technique is available previously occupied sites.
Swift boxes can be placed on any aspect from actionforswifts@gmail.com or The Swift Mapper phone app, launched in
of an existing building, ideally under mail@swift-conservation.org. the autumn of 2018, is available for both
Figure 5a. Recommended positions of internal nest boxes for swifts and house sparrows. Other possibilities include holes in soffits and fascias.
Photo credit Dick Newell.
40 Issue 104 | June 2019
Figure 5b. Recommended
positions of internal nest boxes
for swifts and house sparrows.
Photo credit Dick Newell.
Apple and Android phones. It has the same (NPPF) 2018 in paragraph 175d: When monitoring progress. Where swift bricks are
objectives as the RSPB survey but with the determining planning applications, local not installed, we need to work with council
added flexibility of recording sightings in planning authorities should apply the officers in charge of planning conditions to
the field. Records from the app may be following principles:..... opportunities to ensure bricklayers return and fit them.
exported into other systems such as the incorporate biodiversity improvements in and
RSPB Swift Survey. around developments should be encouraged. Recommendations
In some areas, RSPB data are transferred Many local authorities now include Biodiversity continues to decline in the UK
to local biodiversity records centres for swift nest site provision in Local Plans and swifts are just one species suffering
and Supplementary Planning Guidance as a consequence. The UK Government’s
ease of local access. The value of these
documents. One of the first to do so was ambitious target to build 300,000 homes
datasets increases over time, for example
Exeter City Council (Exeter City Council per year presents an opportunity for effective
the RSPB Swift Survey now contains tens of
2010) and other authorities around the mitigation and compensation for the
thousands of records. Gaps in coverage still
country have followed suit, for example continual loss of existing swift nest sites. We
exist, of course, and lack of records from
the Local Plans for the London Boroughs of propose the following key recommendations
any individual area does not mean swifts
Hackney and Islington require swift bricks for all planning applications.
are absent. The imperative is to provide
new nests to compensate for the gradual to be used in many new developments. • Incorporate nest boxes into development
loss of established sites, help maintain Unfortunately, lack of resource in Planning projects. Nest boxes suitable for multiple
and expand existing colonies and start Authorities means delivery can be ‘hit and species such as swift nest boxes will help
new colonies elsewhere. (See also Further miss’. Officers do not have time to make more species. Although birds of any
Resources below.) checks and may not know the details of kind are good for people’s health and
correct installation. Where measures come wellbeing, budgets should be targeted
Planning policy and proposed as part of a planning application, at species that need help.
the role of ecologists a local authority may not have the • Use data from the mapping tools
Under Section 40 of the Natural Environment knowledge to determine if those proposals together with ecological survey work
and Rural Communities (NERC) Act 2006, are correct. There is therefore an extremely to assess likely impacts on swifts;
public bodies have a duty to protect and important role for ecologists to play here, implement effective mitigation by
enhance all biodiversity. This is supported ensuring they specify the right provision installing enough swift boxes in the
by the National Planning Policy Framework and that it is executed correctly on site by correct location and position.
Issue 104 | June 2019 41Feature Article: The Swift – A Bird
You Need to Help! (contd)
• Wherever possible, incorporate swift include one swift brick per 6 m2 of wall, • If in doubt, ask for advice: the Swift
bricks in new or restored buildings to mounted near the roofline, in clusters Local Network (SLN) group, Swift
increase the overall availability of nest of 3 or more, with approximately 1 m Conservation, Action for Swifts or the
sites for swifts and other species. Birds between entrance holes. RSPB are always available and happy
such as house sparrows can use swift • Try to ensure swift bricks have a to provide help. Check their respective
bricks but swifts cannot use house minimum of 5 m clearance beneath and websites and contact them for one-to-
sparrow nest bricks. in front, and avoid locating them above one advice on a project.
• Integral swift bricks are the preferred doors and windows.
option on new housing developments • ‘Tool-box’ training and on-site
(fitted in clusters of 2 to 4 on gables supervision is essential to ensure swift
and near the roofline where swifts bricks are fitted correctly and in the
would naturally look for a potential nest right places.
site); on larger commercial buildings
Further Resources About the Authors
Distribution data: http://actionforSwifts.blogspot.com John Day is the
RSPB Swift Survey is available at Swift Local Network Groups near you – link from RSPB’s Urban Adviser.
https://swiftsurvey.org/rspb/home/index http://actionforswifts.blogspot.com His work covers
many aspects of the
Swift Survey Data is used to provide Training:
built environment,
GIS layers for administrative areas Swift-related training (on-site and CPE style)
promoting the design
(email: dataunit@rspb.org.uk) for ecologists, architects and planners and landscaping
Advice and case studies: is offered by Swift Conservation of climate-resilient
http://www.rspb.org.uk/helpSwifts (mail@swift-conservation.org) and towns and cities to
http://swift-conservation.org RSPB (Conservation-advice@rspb.org.uk) green space managers and developers,
and encouraging the provision of wildlife
beneficial features.
Contact John at: John.day@rspb.org.uk
Dick Newell is an
References
engineer who, since
Eaton, M., Aebischer, N., Brown, A., Hearn, R., Newell, D. (2019a). Facts about Swift bricks. Action retirement, has
Lock, L., Musgrove, A., Noble, D., Stroud, D. and for Swifts, Swift Conservation, RSPB. Available at focussed on solutions
Gregory, R. (2015). Birds of Conservation Concern tinyurl.com/swiftbricks. Accessed 19 March 2019. to the problem of
4: the population status of birds in the UK, Channel a declining swift
Newell, D. (2019b). Guidance for including bird
Islands and Isle of Man. British Birds, 108: 708-746. population. He
boxes in residential development. Action for
Exeter City Council (2010). Biodiversity Swifts. Available at https://actionforswifts.blogspot. was given a BTO
Requirements of the Exeter Residential Design com/2019/02/guidance-for-including-bird-boxes-in. Marsh Award for
Guide Supplementary Planning Document html. Accessed 19 March 2019. “Innovative Ornithology” in 2016.
(section 9.28). Exeter City Council, Exeter. Several swift nest box designs on the
Roberts, S. (2017). The attitudes of housing market incorporate ideas resulting from
Available at https://drive.google.com/file/
occupants to integral bird and bat boxes.
d/0B4CpCORtOQdTRTNYSENnUXdoNTQ/view. bespoke projects by Action for Swifts.
Unpublished MSc thesis, University of
Accessed 19 March 2019. Contact Dick at:
Gloucestershire. Summary available at https://
Gunnel, K., Murphy, B. and Williams, C. (2013). actionforswifts.blogspot.com/2018/06/the- actionforswifts@gmail.com
Designing for biodiversity: a technical guide for attitudes-of-housing-occupants-to.html.
Edward Mayer runs
new and existing buildings (second edition). Bat Accessed 19 March 2019.
Swift Conservation,
Conservation Trust and RIBA Publishing, London.
Stanbury, A., Brown, A., Eaton, M., Aebischer, N., a free online advice
Available at: http://www.ribabookshops.com/item/
designing-for-biodiversity-a-technical-guide-for-
Gillings, S., Hearn, R., Noble, D., Stroud, D. and service for those
new-and-existing-buildings-2nd-edition/79859/.
Gregory, R. (2017). The risk of extinction for birds wanting to help
in Great Britain. British Birds, 110: 502-517. swifts. He gives talks
Accessed 19 March 2019.
on the conservation
Harris, S.J., Massimino, D., Gillings, S., Eaton, of swifts and
M.A., Noble, D.G., Balmer, D.E., Proctor, D., enhancing urban
Pearce-Higgins, J.W. and Woodcock, P. (2018). biodiversity. His background in property
The Breeding Bird Survey 2017. BTO Research and museum management gives him great
Report 706, British Trust for Ornithology, Thetford.
credibility within the building profession.
Available at https://www.bto.org/volunteer-surveys/
bbs/bbs-publications/bbs-reports. Contact Edward at: Edward.mayer@
Accessed 19 March 2019. swift-conservation.org
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