Sustainable facilities may be deadly for birds
BUILDING or AVIAN
For your sustain- ability practices to truly take
flight, it’s not enough
to green the inside
of your building. Your
facility impacts the rest
of the site surrounding it –
and it may be dangerous to
Glass buildings are beautiful and provide
occupants with much-needed daylight, but
to birds, they frequently appear as uninter-
rupted sky. Colliding with glass is the biggest
known killer of birds in the United States
and is responsible for hundreds of millions
of deaths every year, according to
the American Bird Conservancy.
In addition to the environmental
impact, the sight and sound of
birds slamming into windows are
distressing for the occupants who
witness the phenomenon.
Green practices can’t stop at
Is Your Building Dangerous for Birds?
your doorstep. Read on to discover
how to make your building bird-friendly.
Migratory songbirds such as sparrows, thrushes, and
warblers are typically the most vulnerable, especially during migration periods in spring and fall, explains Christine
Sheppard, bird collision campaign manager for the American Bird Conservancy. Birds typically feed on insects,
some of which can transmit disease or damage trees if
there are fewer birds to control their population.
Unfortunately, some of the same features commonly
used to create sustainable buildings that are healthy for
occupants can be deadly to birds – namely, the increasingly popular expanses of glass. Glass presents a two-pronged problem: depending on how reflective it is, it
can appear as either a transparent view into your indoor
plantings or as a reflection of the sky and outside vegetation. In both cases, birds simply perceive it as space they
can fly through.
Nearby vegetation exacerbates the problem. Birds are
drawn in when they look for places to roost or feed, but
they become confused when they see the same trees or
plantings reflected by glass and may collide with the window attempting to forage in the plants they think they’re
seeing. Try taking a look around your property to find
potential trouble spots.
“Look at all of the types of habitat provision that might
be happening,” says Roderick Bates, an associate and
LEED AP with Kieran Timberlake, a Philadelphia-based
architecture, research, and planning firm. “Do you have
plantings that provide berries and are fruiting during
certain times of year? Do you have water features? How
big are your ledges or parapets?”
Light is also a powerful draw for birds, especially if
your area is foggy or overcast at night, when migration
typically takes place. Intense light projected into the sky
refracts and disorients the birds, who can literally become
trapped in the skyward beams. Buildings that are lit all
night also contribute to the phenomenon.
“They’re drawn to the beams of light like moths,”
explains Deborah Laurel, principal for Prendergast Laurel
Architects. “In places like New York where a lot of lights
shine all night, birds are attracted and get exhausted.
They end up on the ground or find a tree to perch on for a
while. When dawn arrives, they’re in the middle of a glass
canyon, which is disorienting. They forage for some sustenance to keep going, but when it’s bright and sunny, the
reflections of trees and the sky are more intense on any
kind of glass surface and they’re prone to be caught on the