Page 63 - BBC Wildlife Volume 36 #11
P. 63
NEWS FEATURE
enough to spark “serious concern for the Lighting Professionals published ‘Bats and focus on addressing LEDs. “This is an
conservation of the species concerned”. Artificial Lighting in the UK’, offering 25 important first step in raising awareness
Bats face worsening light pollution in pages of guidance for lighting professionals, of the problems with artificial lighting
urban areas, too. In a 2014 report for the designers, planning officers, developers, and how to avoid or reduce them.” She
BCT, Emma Stone of Bristol University bat ecologists and anyone making decisions points out that although people often see
advised that lighting reduces the quantity, about lighting. bats hunting around street lights, this
quality and connectivity of habitats bats Jo Ferguson, Built Environment Officer at behaviour is limited to a few of Britain’s
use for foraging and roosting, including the BCT, says the new guidance has a strong fastest flying species. “Bats risk predation
river corridors, woodland edges and by feeding this way,” she warns.
hedgerows, creating barriers and delaying “Artificial lighting can interfere with
the emergence of light-shy species who where and how bats roost, commute and
miss peak feeding opportunities at dusk Batsandlight feed, which is why the Bat Conservation
up/Getty when insect prey is most abundant. Which are afected? Trust prefers the term ‘reduced-impact’
Stone estimates that almost a quarter of rather than ‘bat-friendly’ lighting.” Bat
Re anzon/naturep .com; noctu e: Theo Douma/AGAMI/A amy; turb nes: Sean Ga
all bat species are threatened worldwide, All UK bats have good eyesight ecologists also want higher standards
with the biggest threats to Europe’s as well as a very sophisticated of sympathetic design and planning, as
bat populations being disturbance, echolocation system, but lighting well as tougher enforcement, says Lisa
urbanisation (including lighting), habitat impacts them in diferent ways. Kerslake, England Vice President of
change, wind turbines and loss of roosts. the Chartered Institute of Ecology and
Environmental Management. “There are
Joined-up thinking LIGHT-SHY BATS concerns and gaps at all levels,” Kerslake
In recent years, warm-spectrum white Slower flying, broad- cautions. “Even where better lighting
LED lighting has been recommended by winged species – is specified and conditioned, this is not
ecologists, architects and town planners, such as the brown always enforced post-development. Many
instead of the blue-rich or UV lighting and grey long- schemes go ahead without any constraint
that can be particularly harmful to bats. eared, greater and on lighting whatsoever.”
Zuidhoek-Nieuwkoop, a town in Holland, lesser horseshoe “Our consultants and local authority
is trialling the replacement of white street (pictured) and several ecologist members encounter frequent
lights with red ones. The Netherlands Myotis bats, including problems in relation to lighting and
Daubenton’s –
Institute of Ecology (NIOO-KNAW) has are strongly averse to white or green its impact on bats. I know of a scheme
Lesser horseshoe: Inak eight dark locations in forest edge habitat. light, and may also be more vulnerable particularly light-sensitive species – were
also tested the impact of these lights at
where lesser horseshoe bats – a
The BCT says there’s still much to
to night-vision hunters. But the full
having to fly across a road to a roost
site under street lights that were not
learn about light and bat behaviour. In
impacts of red light are not clear.
installed to the ecologist’s specifications.
September, the BCT and Institute of
This was rectified, but in many cases it
LIGHT-TOLERANT simply wouldn’t be noticed.”
BATS Many councils currently favour variable
Faster flying, agile species – lighting designs, which are dimmed
such as the serotine, noctule or turned off at critical times for bats,
(pictured) and Leisler’s and the or triggered to light up temporarily by
soprano, common and Nathusius’ passing pedestrians, or are opting for less
pipistrelles – can often be seen bat-reactive colour wavelengths. Such
diving and chasing insect prey around choices rely on rigorous monitoring by
Fatal attraction: white and green lighting, but their ecologists before and after installation.
migratory bats are navigation, life-cycle and natural Light barriers can also be used, such
among the species at behaviour may still be compromised. as planting trees to reduce light ‘spill’.
highest collision risk
from wind turbines. Creating and maintaining dark corridors
through towns and cities is critical to
support some light-shy species, such as
lesser and greater horseshoe bats, grey
and brown long-eared bats and some
Myotis bats, some of which are now
rare in the British Isles.
ALEX MORSS is an ecologist,
bat surveyor and science writer;
alexmorss.co.uk.
GET INVOLVED Learn more about
Britain’s bats – and how you can watch,
survey and help them – at bats.org.uk.
November 2018 BBC Wildlife 63
