BUILDING SUPPLY INDUSTRY ASSOCIATION - Spring 2019 - 11

FEATURE

|

BY KRISTA DE GROOT

BIRD-GLASS
COLLISIONS:
CONSERVATION OPPORTUNITIES FOR
THE BUILDING SUPPLY INDUSTRY

B

irds have inspired us for
millennia and feature in
human art dating back to
prehistoric times. They play an
important role in maintaining
the health of our ecosystems
and provide services with
significant economic value
including: pest control,
pollination and seed dispersal.
Bird watching and bird feeding
are popular pastimes among
all age groups, including
youth, and these multi-million
dollar industries are growing
quickly. However, many bird
populations are in steep
decline and face a range of
conservation issues including
threats related to urban
development, such as habitat
loss and collisions with glass.
While it may seem incongruous
to feature an article on birds
in a building supply industry
magazine, there are concrete
and meaningful actions that
can be taken by this industry to
address these threats.
Most people have heard the telltale
thud or witnessed a bird killed by
striking a window. When you factor
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all the birds that are killed by hitting
our homes, institutional buildings and
commercial towers, the resulting figure
is startlingly high. Up to 41 million birds
are estimated to be killed by colliding
with glass on buildings in Canada
every year (Machtans et al. 2013). The
tally may be close to a billion birds
per year in the U.S. (Loss et al. 2014).
While individual tall towers can kill a
lot of birds, particularly in cities that
are situated along major migration
routes, the vast majority of
bird-window collision deaths occur
at homes. This is simply a function of
the relative number of single-family
homes in Canada, compared to other
building classes.
Both the clear and the reflective
properties of glass make it hazardous
to birds. Clear glass on walkways
or glass railing systems are deadly
because they provide an illusion of
clear passage. Birds are able to see
sky, trees or other vegetation on
one side of the glass, which they
attempt to access. This is much like
our own propensity to walk into
glass doors when our attention is
diverted, when we are in a rush, or
if we are not expecting an obstacle.
The speed at which birds move
through their environment results in

high-impact collisions that are often
immediately fatal. The reflection of
trees and shrubs in windows creates
an additional hazard to birds. Birds
see these reflections and attempt
to fly into the mirror image of
the vegetation.

Single decals are ineffective
Solutions exist to mitigate this
problem. Numerous municipalities
and more recently, university
campuses, have developed
bird-friendly architectural guidelines
to ensure that buildings are
designed at the outset to minimize
bird-window collisions. There are
also many retrofit products that
can be applied to existing building
windows, and bird-friendly glass can
be used for window replacement
projects or new builds. The principle
for making glass safe for birds
is simple: we need to convince
birds that glass is a solid barrier.
This is tricky because many species
of birds have evolved to fly through
narrow spaces (between tree
branches in the forest, for example).
Therefore, fixing one object or decal
on a window does not prevent birds
from colliding with the remaining
unmarked window.
SPRING 2019 | BSIA NEWS | NEWS MAGAZINE

11


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Table of Contents for the Digital Edition of BUILDING SUPPLY INDUSTRY ASSOCIATION - Spring 2019

https://www.nxtbook.com/naylor/BSPS/BSPQ0320
https://www.nxtbook.com/naylor/BSPS/BSPQ0220
https://www.nxtbook.com/naylor/BSPS/BSPQ0120
https://www.nxtbook.com/naylor/BSPS/BSPQ0419
https://www.nxtbook.com/naylor/BSPS/BSPQ0319
https://www.nxtbook.com/naylor/BSPS/BSPQ0219
https://www.nxtbook.com/naylor/BSPS/BSPQ0119
https://www.nxtbook.com/naylor/BSPS/BSPS0518
https://www.nxtbook.com/naylor/BSPS/BSPS0318
https://www.nxtbook.com/naylor/BSPS/BSPS0218
https://www.nxtbook.com/naylor/BSPS/BSPS0118
https://www.nxtbook.com/naylor/BSPS/BSPS0617
https://www.nxtbook.com/naylor/BSPS/BSPS0517
https://www.nxtbook.com/naylor/BSPS/BSPS0417
https://www.nxtbook.com/naylor/BSPS/BSPS0317
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