BIRD
SAFE BUILDING GUIDELINES
2 BIRD-SAFE BUILDING GUIDELINES
Thank you to New York City Audubon and their original working group
for permission to revise their Bird-Safe Building Guidelines (May 2007).
NYC Project Director: Kate Orff, RLA, Columbia University GSAPP
NYC Authors: Hillary Brown, AIA, Steven Caputo, New Civic Works
NYC Audubon Project Staff: E.J. McAdams, Marcia Fowle, Glenn Phillips,
Chelsea Dewitt, Yigal Gelb Graphics.
NYC Reviewers: Karen Cotton, Bird-Safe Working Group; Randi
Doeker, Birds & Buildings Forum; Bruce Fowle, FAIA, Daniel Piselli,
FXFOWLE; Marcia Fowle; Yigal Gelb, Program Director, NYC Audubon;
Mary Jane Kaplan; Daniel Klem, Jr., PhD., Muhlenberg College; Albert M.
Manville, PhD., US Department of the Interior, Fish and Wildlife Service;
E. J. McAdams, Former Executive Director NYC, Audubon; Glenn
Phillips, Executive Director, NYC Audubon.
Original publication of these guidelines was made possible with the
support of US Department of the Interior, Fish and Wildlife Service
through the Neotropical Migratory Bird Conservation Act, Joseph &
Mary Fiore and the support of NYC Audubon members and patrons.
Bird-Safe Building Guidelines
Over 100 bird species have been recovered from building collisions in Minnesota including Lincoln’s Sparrow, Black-capped Chickadee, Indigo Bunting, Common Yellowthroat, and Nashville Warbler
The mission of Audubon Minnesota is to conserve and restore natural
ecosystems, focusing on birds and their habitats, for the benefit of
humanity and the earth’s biological diversity.
AUDUBON MINNESOTA
2357 Ventura Drive, Suite 106
• Saint Paul MN 55125
mn.audubon.org
Published by Audubon Minnesota, May 2010
Project Director: Joanna Eckles (Audubon Minnesota)
Contributor: Edward Heinen (Perkins + Will)
Reviewers: Mark Martell, Mark Peterson (Audubon Minnesota); Lori
Naumann (Minnesota Department of Natural Resources); Chris
Sheppard (American Bird Conservancy); Susan Elbin (NYC Audubon);
Jonee Kulman Brigham (Center for Sustainable Building Research,
UMN), Benjamin Sporer, Paul Neuhaus (Perkins + Will)
Design Manager: Bonita Jenné (Audubon Minnesota)
Cover Cityscape Artwork: Edward Heinen
Printing made possible by TogetherGreen
Citation: Audubon Minnesota. (2010). Bird-Safe Building Guidelines
Photographs in this publication are copyrighted by the individual
photographers and have been used with permission. Site and lighting
diagrams courtesy of the City of Toronto from their Bird-Friendly
Development Guidelines.
JIM WILLIAMS
JIM WILLIAMS
MIKE LENTZ
MIKE LENTZ
MIKE LENTZ
BIRD-SAFE BUILDING GUIDELINES 3
Table of Contents
INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
BIRDS AND BUILDINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Birds and the Built Environment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Birds and Building Green. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Causes of Collisions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Factors Affecting Bird Collisions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Project BirdSafe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
BEST PRACTICES FOR BIRD SAFETY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Comprehensive Planning for Bird Conservation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Site and Landscape Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Building Layout and Massing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Exterior Glass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Emerging Technologies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Lighting Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Building Operations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Comprehensive Site Strategy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Modifications to Existing Buildings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
CONCLUSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
CASE STUDIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Products and Innovations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Local Resources. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
MIKE LENTZ
Dark-eyed Junco
4 BIRD-SAFE BUILDING GUIDELINES
Bird-building collisions
are an unfortunate side
effect of our expanding
built environment and
a proven problem
in Minnesota and
throughout the world.
These are just a portion
of the birds collected
from Toronto window
collisions in 2009.
KENNETH HERDY
BIRD-SAFE BUILDING GUIDELINES 5
INTRODUCTION
G
LAZED BUILDINGS THAT MAKE UP MODERN CITY
skylines and suburban settings along with countless windows
in our homes present serious hazards for birds. In the United States,
hundreds of millions of birds perish each year from collisions with
buildings.
1
In Minnesota, bird-window collisions are a proven problem. Over
100 species of birds have been documented at just a small number of
buildings being monitored throughout the state. Birds are killed or
injured as a result of clear and reflective glass. Artificial lighting also
confounds night-migrating species.
In addition, increased interest in “building green” often results
in both desirable habitat for birds and large expanses of glass – a
deadly combination.
Fortunately, awareness and preventative actions are emerging.
Internationally, Lights Out programs are aiding night migrants in a
growing number of cities. And by incorporating bird-safe building
design strategies as part of an integrated sustainable design program,
we can help save countless resident and migratory birds.
These Bird-Safe Building Guidelines expand upon ongoing Project
BirdSafe initiatives in Minnesota to address bird-building collision
issues at the building design level. Utilizing New York City
Audubon’s 2007 Bird-Safe Building Guidelines and other resources,
established standards for bird-safe building enhancements have
been updated and adapted to provide local examples and references.
These guidelines are intended for use by those involved in building
design and operations. They promote measures to protect birds in
the planning, design, and operation stages of all types of buildings,
in all settings and have been updated to reflect implementation
criteria in LEED® v3 (2009).
Bird-safe building criteria are scheduled to be incorporated into B3
State of Minnesota Sustainable Building Guidelines (B3-MSBG)
in 2010. B3-MSBG is required for all new construction and major
renovations that receive state bond money. B3-MSBG covers the
planning, design, construction, and operation of buildings.
2
DID YOU KNOW?
Birds are an important asset to the travel and recreational sectors of the economy. According to the
United States Fish and Wildlife Service, bird-watching is the second fastest growing leisure activity in
North America. An estimated 63 million Americans participate in wildlife watching and eco-tourism
each year. In the process, they spend close to $30 billion annually, with a major portion related to
birds.
3
With fully one-third of Minnesotans self-identifying as bird-watchers,
4
the health of our birds and
their habitats is economically as well as ecologically imperative.
“Architects And
their clients cAn
use All the recycled
mAteriAl they wAnt.
they cAn sAve All the
energy they wAnt,
but if their building
is still killing birds,
it’s not green to me.”
Dr. Daniel Klem,
Muhlenberg College,
Audubon, Nov-Dec 2008
Injured Golden Crowned Kinglet
NYC AUDUBON
6 BIRD-SAFE BUILDING GUIDELINES
BIRDS AND BUILDINGS
Birds and the Built Environment
DID YOU KNOW?
Buildings contribute substantially to greenhouse gas emissions, which in turn adversely impact native and migratory birds. Building
operations consume over 75% of the electricity in the U.S. In 2007, the commercial building sector alone produced more than 1 billion
metric tons of carbon dioxide, an increase of 4.4% from 2006 levels, and an increase of over 38% from 1990 levels.
6
Research provides clear
evidence of the negative effects of climate change on the migration, breeding, numbers, and behavior of many North American bird species.
7
IN RECENT DECADES, sprawling land-use patterns and
intensified urbanization have degraded the quantity and quality
of bird habitat throughout the globe. Cities and towns cling to
waterfronts and shorelines, and increasingly infringe upon the
wetlands and woodlands that birds depend upon for food and
shelter. Loss of habitat makes city parks, streetscape vegetation,
waterfront business districts, and other urban green patches
important resources for resident and migratory birds. There birds
encounter the nighttime dangers of illuminated structures and the
daytime hazards of dense and highly glazed buildings.
The increased use of glass poses a distinct threat to birdlife. From
urban high-rises to suburban office parks to single-story structures,
large expanses of glass are now routinely used as building enclosure.
Energy performance improvements in transparent exterior wall
systems have enabled deep daylighting of building interiors, often
by means of floor-to-ceiling glass expanses. The aesthetic and
functional pursuit of still greater visual transparency has spurred the
production of ultra-clear glass.
The combined effects of these factors have led scientists to
determine that bird mortality caused by building collisions is
a biologically significant
5
issue. In other words, it is a threat of
sufficient magnitude to affect the viability of bird populations,
leading to local, regional, and national declines.
Songbirds – already imperiled by habitat loss and other
environmental stressors – are especially vulnerable during migration
to daytime and nighttime collisions as they seek food and shelter
among urban buildings. Researchers have documented hundreds of
thousands of building collision-related bird deaths nationally during
migration seasons. Included in this toll are specimens representing
over 225 species, a quarter of the species found in the United States.
Stunned Brown CreeperLow-density development generally results in habitat loss Architectural trends favor use of glass
Bird populations,
already in decline from
loss of habitat, are
further threatened by
the incursion of man-
made structures into
avian air space.
JOEL DUNNETTE
BIRD-SAFE BUILDING GUIDELINES 7
A green roof is one way we “build green” American Redstarts weigh less than 1/2 ounce but their migration route may cover more than 2500 miles
Birds and Building Green
SUSTAINABLE, HIGH-PERFORMANCE BUILDINGS are
designed to conserve energy and reduce carbon emissions, conserve
water resources, harvest daylight and provide healthy indoor
environments. These buildings conserve and recycle materials and
display unprecedented levels of environmental responsibility and
functionality. They are integrated with their natural surroundings
and often enhanced with native landscaping.
The green building movement is an exciting advancement for
architects, designers, building users and conservationists alike.
But it is not without pitfalls. Unless carefully considered, greening
efforts may actually contribute to the loss of the very creatures we
seek to protect. Ironically, in our desire to bring the outside in,
we may increase risks to birds. By attracting birds in and around
glazed buildings we inadvertently increase the risk of bird-window
collisions. Better sustainable design practices therefore demand that
buildings also be designed to integrate specific bird-safe strategies.
“there is nothing
in which the birds
differ more from
mAn thAn the wAy
in which they cAn
build And yet leAve A
lAndscApe As it wAs
before.”
Robert Lynd, The Blue Lion
and other essays
Advocating bird-safety in buildings should be integral to the green
building movement. Many of the strategies for reducing bird
collisions complement other sustainable site and building objectives.
In concert, efforts to reduce collision hazards, enhance and restore
habitat and conserve energy help native and migratory birds.
While development poses a myriad of risks to birds, the movement
towards sustainability and collaboration offers hope. Those
leading the shift to building green are well suited to stimulate the
development of new glazing technologies and to create a market for
all bird-safe building products. If builders and developers demand
it, much-needed advancements will follow.
Bird populations are remarkably resilient and can respond well to
conservation efforts. By incorporating bird-safe building design
strategies as part of an integrated sustainable design program, we
can help birds thrive in our built environment.
MIKE LENTZ
8 BIRD-SAFE BUILDING GUIDELINES
BIRDS AND BUILDINGS
Causes of Collisions
DAYTIME COLLISIONS occur because most birds do not perceive glass as an obstacle. Migratory birds in particular have not evolved
to live in built environments and don’t see the context cues that indicate that glass is solid.
8
Instead they see the things they know and need,
such as habitat and open sky, reflected in the glazed surface or on the other side of one or more panes of glass.
Collisions occur at glass facades of all sizes, in all seasons and weather conditions, and in every type of environment from residential and
rural settings to dense urban cores. Collisions and mortality occur at any place where birds and glass coexist.
1
As a result, daytime collisions
are likely the most prevalent of all building collision hazards.
Birds have two key
issues with buildings –
one relates to glass, the
other to lighting.
From outside most buildings, glass often appears highly
reflective. Under the right conditions almost every type
of architectural glass reflects the sky, clouds, or nearby
trees and vegetation, reproducing a perceived habitat
familiar and attractive to birds. Birds fly from the real
habitat to the reflected habitat or sky and hit the glass
in between.
PROBLEM GLASS REFLECTIVITY: MIRROR EFFECT
The trick of transparency is exacerbated when windows
are installed directly across from one another or at
a corner because birds perceive an unobstructed
passageway and attempt to fly through the glass. In
Minnesota, glass linkways and skyways are commonly
used to protect people from the elements and often
cause bird collisions.
PROBLEM GLASS TRANSPARENCY: FLY THROUGH
Problem: Reflection Problem: Transparency
BIRD-SAFE BUILDING GUIDELINES 9
NIGHTTIME COLLISIONS occur because the illumination of buildings creates a beacon effect for night-migrating birds. When
weather conditions are favorable, these birds tend to fly high (over 500 feet) and depend heavily on visual references to maintain their
orientation. However, during inclement weather, they often descend to lower altitudes, possibly in search of clear sky celestial clues or
magnetic references and are liable to be attracted to illuminated buildings or other tall lighted structures.
Night lighting also affects daytime collisions by temporarily increasing the number of migratory birds in urban areas. When the sun rises and
those “trapped” birds begin to move about, forage or seek an escape, they often encounter the deadly effects of reflective and transparent glass.
Heavy moisture (humidity, fog or mist) in the air greatly
increases the illuminated space or “skyglow” around buildings,
regardless of whether the light is generated by an interior or
exterior source. Birds become disoriented and entrapped
while circling in the illuminated zone and are likely to succumb
to exhaustion, predation, or lethal collision.
When night-migrating birds become trapped in a dense urban
area they often fly towards illuminated lobbies and atria on
lower levels. Potted plants inside the glass can be a deadly lure
as birds seek safety and do not perceive the glass in their way.
DID YOU KNOW?
In addition to the adverse impacts on migrating birds, significant economic and health incentives exist for curbing light pollution. Overly lit
buildings waste tremendous amounts of electrical energy, increasing greenhouse gas emissions and air pollution levels, and of course, wasting
money. Researchers estimate that the United States alone wastes over one billion dollars on electricity annually because poorly designed or
improperly installed outdoor fixtures allow much of the lighting to go up to the sky.
9
In addition to the threat this poses to birds and other
animals, “light pollution” has significant aesthetic and cultural impact as well. Studies estimate that over two thirds of the world’s population
can no longer see the Milky Way, which humans have gazed at with a sense of mystery and imagination for millennia. Together the ecological,
financial and aesthetic/cultural impacts of excessive lighting serve as compelling motivation to reduce and refine light usage.
“even the dArkness
moves with the
pAssAge of birds.
on soft spring
midnights, the Air is
Alive with the flight
notes of unseen
birds filtering
down through the
moonlight like the
voices of stArs.”
Scott Weidensaul,
Living on the Wind
PROBLEM ILLUMINATED ATRIA
PROBLEM BEACON EFFECT
Problem: Beacon
effect, illumination
NYC AUDUBON
10 BIRD-SAFE BUILDING GUIDELINES
Factors Affecting Bird Collisions
PROXIMITY TO STOPOVER LOCATIONS. Birds make stopovers in
waterfront, wetland, grassland, and wooded environments that are now
America’s most densely populated urban areas. Migrating birds have a
significant chance of encountering at least one major metropolitan area
during migration between breeding and wintering grounds. Birds need
stopover sites to refuel. Building sites located near bird feeding areas,
waterfront habitat, or patches of urban vegetation experience increased
risk of bird collisions.
MIGRATION. Collisions tend to increase each spring and fall when
local bird populations are boosted by a huge influx of migrants traveling
between breeding and wintering grounds. Songbirds travel primarily at
night in a “broad-front” migration following several major flyways. These
historic routes follow major rivers, coastlines, mountain ranges, and
lakes. Along the way densely built urban areas have become migration
danger zones.
PLANNING BIRD-SAFE ENVIRONMENTS for both new and existing buildings requires an assessment of existing conditions.
Conditions affecting bird collisions include migration, proximity to stopover locations, proximity to feeding grounds, glass coverage and
glazing characteristics, building orientation and massing features, lighting, weather conditions, and building height.
MIGRATION
IN MINNESOTA
Minnesota is on the
Mississippi Flyway.
About 40% of all
North American
waterfowl and 326
species of birds (1/3
of all species in North
America) use the
Mississippi Flyway on
their spring and fall
migrations. Our peak
migration months are
May, September and
October.
BIRDS AND BUILDINGS
Radar captures masses of migrating birds as seen from each station Glass hi-rise near key habitat
S.A. GAUTHREAUX, JR.
BIRD-SAFE BUILDING GUIDELINES 11
PROXIMITY TO FEEDING AND HABITAT AREAS. Sites bordering
parkland, pocket parks, habitat patches, green roofs, and street-tree
corridors threaten birds since they forage in these areas for food.
Building sites near water bodies and wetlands – no matter how small
– put both resident and migrant species at risk. Suburban building sites
with proximity to natural landscapes also present a range of hazards and
can be even more dangerous to birds than urban settings.
GLASS COVERAGE AND GLAZING CHARACTERISTICS. A major
determinant of potential strikes is the sheer percentage of glass used on
the building facade. In general, collisions will occur wherever glass and
birds coexist. Ground level and low stories are the major collision zones.
At these levels large expanses of monolithic glazing should be minimized,
glazing reflectivity (especially when adjacent to landscapes) reduced, and
“fly-through” situations eliminated.
BUILDING ORIENTATION AND MASSING FEATURES. Since
migratory routes are broad and flight patterns vary, one cannot simply
address building facades that face an assumed direction of migration.
The impacts of all facades, with special emphasis on those adjacent to
landscapes or other features attractive to birds, must be considered.
For example, landscaped courtyards and glass vestibules can be very
confusing and difficult for birds to negotiate.
LIGHTING AND WEATHER. Regions that are prone to haze, fog, mist,
and/or low-lying clouds may see more frequent bird-kills, especially if the
area contains tall buildings that are highly illuminated. Generally, there are
fewer birds aloft during precipitation; however, inclement weather can
develop, reducing their navigational awareness and forcing them to fly at
lower altitudes in search of visual clues. Heavily illuminated buildings in
their path can serve as deadly lures.
Birds use urban green spaces
How a building is situated on a property affects collision rates Bright lighting oriented skyward draws birds in
Glass confuses birds by reflecting sky or habitat
NYC AUDUBON
NYC AUDUBON
12 BIRD-SAFE BUILDING GUIDELINES
BUILDING HEIGHT
TALLEST:
While birds’ migratory paths vary, radar tracking has determined that
approximately 98% of flying vertebrates (birds and bats) migrate at
heights below 1640 feet during the spring, with 75% flying below that
level in the fall.
10
Today, many of the tallest buildings in the world reach
or come close to the upper limits of bird migration.
11
Storms or fog,
which cause migrants to fly lower and can cause disorientation, can put
countless birds at risk during a single evening. Any building over 500 feet
tall is an obstacle in the path of avian nighttime migration and must be
thoughtfully designed and operated to minimize its impact.
MODERATE HEIGHT:
Buildings between 50 and 500 feet tall pose hazards since migrating
birds descend from migration heights in the early morning to rest and
forage for food. Migrants also frequently fly short distances at lower
elevations in the early morning to correct the path of their migration,
making moderate-height buildings, especially if reflective or transparent,
a serious hazard.
LOWER LEVELS:
The most hazardous areas of all buildings, especially during the day
and regardless of overall height, are the ground level and bottom few
stories. Here, birds are most likely to fly into glazed facades that reflect
surrounding vegetation, sky and other attractive features.
BIRDS AND BUILDINGS
Many urban areas, like Saint Paul (above) have developed along key migration corridors like the Mississippi River
SONGBIRDS & RAPTORS
2,000’
WATERFOWL
SHORE BIRDS
DAYTIME COLLISION ZONE
1,500’
500’
1,000’
250’
Info Credit: Fox & Fowle Architects
Bruce Fowle, E.J. McAdams - 3/11/05
50’
Fox & Fowle Architects - Bruce Fowle, E.J. McAdams, March 11, 2005
BIRD-SAFE BUILDING GUIDELINES 13
Project BirdSafe
LIGHTS OUT. Bright lights make beautiful skylines but they can also
disorient migrating birds and lead to deadly collisions with buildings.
In 2007 an ongoing Lights Out program was established as a core
Project BirdSafe program. Lights Out was embraced early by both the
Minneapolis and St. Paul Building Owner’s and Manager’s Associations
(BOMA) and had an immediate effect on the Twin Cities skylines.
Lights Out buildings extinguish all possible interior and exterior lighting
after midnight during both spring and fall migration. See page 26.
In 2009 the State of Minnesota passed a “Lights Out” law requiring all of
the over 5,000 state owned and leased buildings to adhere to our Lights
Out criterion in order to save birds and energy.
PARTNERS
Audubon Minnesota
Audubon Chapter of
Minneapolis
Bell Museum of
Natural History
BOMA Greater
Minneapolis
BOMA Saint Paul
DNR Non-game
Wildlife Program
National Parks Service
Perkins + Will
Minneapolis
St. Paul Audubon
Society
Wildlife Rehabilitation
Center
Zumbro Valley
Audubon Society
11:55 pm
12:05 am
PROJECT BIRDSAFE WAS ESTABLISHED IN MINNESOTA in 2007 as a result of growing international concern over the impact
of bird collisions. Minnesota joins a growing network of individuals and organizations working to reduce hazards to birds from building
collisions. Key Project BirdSafe initiatives include Lights Out, research, building monitoring, and bird safe buildings.
RESEARCH AND MONITORING. To answer key questions about the
numbers and types of birds affected by collisions in Minnesota, Project
BirdSafe volunteers monitor specific research routes in downtown
Minneapolis, St. Paul and at Rochester’s Mayo Clinic for dead and injured
birds. These routes, while representing only a tiny subset of Minnesota
structures, are designed to sample a variety of dense urban buildings.
Findings help researchers to better understand some of the local
conditions that contribute to bird collisions.
BIRDSAFE BUILDINGS. Ultimately the work done here and
throughout the world to understand and quantify the problem
of bird-building collisions must lead to action. Those who
design and operate buildings are perfectly positioned to make
design decisions that not only save birds day to day but also
create markets for bird-safe products.
To increase awareness of bird safety in the architecture and
planning community, Audubon Minnesota worked with New York City
Audubon to revise these Bird-Safe Building Guidelines for distribution
in Minnesota. This publication serves as an important first step towards
increasing awareness and adoption of strategies locally to reduce
hazards to native and migratory birds using this key migration corridor.
Minneapolis before and after “Lights Out” on the same April night
Ovenbirds (left) and Nashville Warblers (right) are common Minnesota collision victims
PER BREIEHAGEN
TAMI VOGEL / CLAUDIA EGELHOFF
14 BIRD-SAFE BUILDING GUIDELINES
BEST PRACTICES FOR BIRD SAFETY
Comprehensive Planning for Bird Conservation
Objective:
Incorporate bird-
friendly policies and
activities in design
and development of
urban spaces. Raise
awareness of bird
collision issues.
THE INCREASED INTEREST IN BUILDING GREEN creates
genuine opportunities to address broader conservation issues in the
design and planning of our urban and suburban spaces. A building’s
effect on the local, regional, national and international environment
over its lifetime is reflected in energy and resource use, waste
management, daily operations and direct environmental impact.
Bird safety is one clear and direct impact that can be creatively
addressed through collaborative comprehensive planning.
Birds are an ideal focus of community wide conservation efforts
because they are a sentinel of overall environmental health.
Stewardship strategies that benefit birds and their habitats also
benefit a myriad of other plants and animals. These strategies go
beyond those related to buildings and infrastructure just as bird-
friendly design includes more than glass and lighting choices.
These Guidelines encourage participation in natural resource-
based planning to protect and restore native and migratory bird
species of Minnesota. This type of planning benefits communities
by emphasizing vital natural assets, involving citizens in natural
resource monitoring and helping to prevent unwise patterns of
development which lead to disconnected fragments of open space,
poor water quality and diminished community character.
Collaboration among diverse disciplines is a valuable and uniquely
innovative aspect of sustainable design and development. Such an
approach calls upon key participants to work beyond conventional
planning and design that relies on the expertise of specialists
working in isolation. Through collaboration, participants develop
an enhanced understanding of how specialized knowledge can
inform the design process. This new insight creates the potential
for innovative design solutions to protect natural resources while
improving the quality of life for communities.
Key participants in natural resource-based planning include design
and engineering professionals, natural science professionals and
citizen scientists, government agencies, and advocacy organizations.
Prairie planting at Thomson Reuters Native plantings at Aveda headquarters reflect corporate commitment to the environment Renewable energy helps birds
BIRD-SAFE BUILDING GUIDELINES 15
“by improving our
cities for birds
we enhAnce our
own lives And
the strength of
our community.
protection of birds
in An urbAn AreA
presents pArticulAr
chAllenges thAt
cAn best be met by
developing strong
And creAtive
pArtnerships.”
Kent Warden
Executive Director
BOMA Greater
Minneapolis
BIRDS AND URBAN PLANNING
The Minnesota Land Planning Act, (Minn. Stat. 473.852.869)
requires that communities submit comprehensive plans in
accordance with the Metropolitan Planning Council’s 2030 Regional
Development Framework, which includes protection of natural
resources as a primary goal.
12
Native and migratory birds are a
valuable natural resource.
Several North American cities have made birds a priority. The City
of Chicago has developed a Bird Agenda to showcase, outline and
carry forward city-wide initiatives benefiting birds. They have also
signed an Urban Conservation Treaty for Migratory Birds with the
US Fish & Wildlife Service, an agreement to conserve birds through
education and habitat improvement.
The City of Toronto recently made history by being the first city
to make it mandatory for all new construction to meet specific
standards for bird safety. They have also produced and distributed
a book of Bird-Friendly Development Guidelines
13
and undertaken
a broad Biodiversity Campaign to educate their citizens about the
natural environment in and around Toronto with birds as their
initial focus.
14
There is tremendous potential in our urban centers to make
meaningful behavior adjustments to benefit the natural
environment. Working collaboratively between specialties and
among cities we can create a network of habitat corridors and
safe areas for birds to live and breed or to pass through unharmed
between summer and wintering grounds. In the process we benefit
countless other creatures and ourselves.
Best Practices for Bird Safety
Best Practices included in this section make specific
recommendations toward the planning, design, retrofit, and
operation of buildings to minimize bird collisions. The strategies
included complement the LEED (Leadership in Energy and
Environmental Design) Green Building Rating System™ as well as
the Minnesota Sustainable Building Guidelines (B3-MSBG).
The LEED system is the U.S Green Building Council’s nationally
accepted standard of sustainability for the commercial,
residential, and institutional building industries. Provisions related
to bird safety and landscaping are included in the latest version of
LEED v3 (2009).
LEED challenges practitioners to assess the impact of building and
site development on wildlife, and incorporate measures to reduce
threats that buildings pose to birds. Buildings may be certified
as silver, gold or platinum according to the number of credits
achieved in seven categories:
1. Sustainable Sites (SS)
2. Water Efficiency (WE)
3. Energy and Atmosphere (EA)
4. Materials and Resources (MR)
5. Indoor Environmental Quality (IEQ)
6. Innovation and Design Process (ID)
7. Regional Priority (RP)
Additionally, bird-safe building criteria are planned for inclusion
into Minnesota Sustainable Building Guidelines, as part of the
Buildings, Benchmarks, and Beyond Program (B3-MSBG) in 2010.
2
DID YOU KNOW?
If you imagine the most populous North American cities arranged horizontally as a horizon line or “birds-eye view” they cover over 40% of
the width of North America. Many cities are concentrated on key migration routes, making them nearly impossible for birds to avoid.
10
16 BIRD-SAFE BUILDING GUIDELINES
BEST PRACTICES FOR BIRD SAFETY
Site and Landscape Design
Objective:
Minimize the potential
for bird collisions when
siting buildings near
existing landscape
features and when
planning new
landscapes in close
proximity to buildings.
A WELL-INTEGRATED SUSTAINABLE DESIGN enhances open space and protects and restores habitat while enhancing the overall
architectural and operational quality of a built facility. Efforts to integrate nature and attract wildlife should be balanced with specific
considerations of a site’s impact on birds. Birds attracted to on-site habitat are vulnerable to collisions with glass. These guidelines encourage
bird-safe design strategies early in the collaborative design process through consideration of site, existing habitat, and bird-safe landscaping.
Analyze the site to determine potential attractions for bird populations.
Consult with an ecologist or bird specialist to inventory the site.
Document the location of nearby vegetated streetscapes and urban
parks.
Identify all sources of food and shelter for migratory and resident bird
populations, including plants, water and other natural features.
Identify human-made features that attract birds, including water
sources, nesting and perching sites, and shelter from adverse weather.
15
CONSIDER SITE ANALYSIS
Site building(s) to reduce conflicts with existing and planned landscape
features that may attract birds.
Where buildings cannot be located away from bird sensitive areas, take
special care in treating windows. See “Exterior Glass” pages 20-21.
Where strategic reductions to building footprint have been made in
order to enhance vegetated open space and habitat, assess site conflicts
and include bird safe treatments.
Use soil berms, furniture, landscaping, or architectural features to
prevent reflection in glazed building facades.
CONSIDER EXISTING HABITAT
LEED
LEED
Coordinate with LEED Credits
SS 5.1 Site Development: Protect or Restore Habitat
Coordinate with LEED Credits
SS 5.2 Site Development: Maximize Open Space
Urban parks attract birds Treat windows near habitat
BIRD-SAFE BUILDING GUIDELINES 17
WHILE BIRDS COLLIDE WITH BUILDINGS AT ALL LEVELS, ground-level stories are considered the most dangerous because this
is where habitat reflections, glazing and internal planting are often all quite prominent. Analysis of bird collision data over 10 years in New
York City showed that “most collisions were documented to occur during the day at the lower levels of buildings where large glass exteriors
reflected abundant vegetation, or where transparent windows exposed indoor vegetation.”
16
Birds are vulnerable to collisions nearly anywhere glass occurs. Habitat
in proximity to glass exacerbates this threat unless reflections are
avoided or eliminated or visual cues are incorporated in glazing.
When planning new landscapes be aware of reflections and see-through
effects created by habitat in relation to building features. Place plantings
to minimize these effects.
Alternatively, situate trees and shrubs immediately adjacent to the
exterior glass walls, at a distance of less than three feet from the glass.
17
Close proximity will minimize habitat reflections. In addition, if a bird
does try to fly to a reflection at this range, flight momentum will be
minimal, thereby reducing fatal collisions. This planting strategy also
provides beneficial summertime shading and reduces cooling loads.
If any bird-attracting features (food, water, shelter) are in reflective
range of the building(s), use fritting, shading devices or other techniques
to make glass visible. See “Exterior Glass” pages 20-21.
CONSIDER LANDSCAPE PLACEMENT
Birds will mistakenly seek shelter in landscaping located behind glass.
Mask views of interior plantings from outside the building.
Use screening, window films or treatments to make glass visible.
With the increased use of green roof technology, impacts on birds must
be considered.
Treat glass to minimize the reflection of rooftop landscaping in adjacent
building features.
Consider foregoing green roof installation or eliminating access to birds
if reflection in adjacent buildings will occur.
CONSIDER INTERIOR LANDSCAPING
CONSIDER ROOFTOP LANDSCAPING
LEED
Coordinate with LEED Credits
SS 7.1 Heat Island Effect: Non-Roof
SS 7.2 Heat Island Effect: Roof
Dangerous reflections Confusing interior plants
CANOPY HEIGHT
Glass treatments
should be applied to
the height of the top
of the surrounding
tree canopy or the
anticipated height of
surrounding vegetation
at maturity.
13
18 BIRD-SAFE BUILDING GUIDELINES
BEST PRACTICES FOR BIRD SAFETY
Building Layout and Massing
Objective:
Include bird-safe
strategies as part of
an integrated design
approach before
construction rather
than retrofitting a
building that proves
problematic.
BIRD-SAFE STRATEGIES do not restrict the ability to design creatively. These guidelines encourage an integrated design approach,
challenging building designers to include bird-safe strategies to enhance aesthetic, functional, and building performance goals. The layout
of individual buildings and their relationship to other structures on the site can affect the number of bird collisions that occur. Building
layout and massing can be planned along with landscaping to minimize the likelihood of bird collisions.
CONSIDER SPECIFIC SITE FEATURES
Ground level stories are the most hazardous areas of all buildings and
should be designed to minimize bird collisions.
Minimize those hazards that bring birds close to buildings such as
vegetation, water and other features.
Provide uniform covering with bird-safe materials, especially adjacent to
landscapes. See “Exterior Glass” pages 20-21.
Use angled glass, between 20 and 40 degrees from vertical, to reflect
the ground instead of adjacent habitat or sky.
18
Clear barriers such as transparent bus-shelters, skyways, linkways,
railings, windscreens and noise barriers create a serious hazard for birds
because they are invisible, causing a deadly fly-through hazard.
Avoid use of transparent materials in these structures in any location
where birds may be present. Use translucent or decorative glazing as
an alternative.
If clear panels of any kind are in use, incorporate surface treatments to
make glass visible. See “Exterior Glass” pages 20-21.
Clear barriers create a deadly hazard for birds
These two birds were fooled by habitat reflections
BIRD-SAFE BUILDING GUIDELINES 19
“bird sAfety is eAsier
to sell when it
overlAps with other
green strAtegies.
slAnted glAss
reduces solAr heAt
gAin but Also works
to effectively reduce
bird injuries. fritted
glAss reduces heAt
gAin, And if it’s 50%
you cAn still see
through it.”
Jeanne Gang, Studio Gang
Architects, Chicago
Courtyards may contain landscaping and confusing internal corners that
limit bird escape routes. These areas often allow sudden access by people
that flush birds into glass.
Control access to enclosed areas so birds flush away from glass into
open areas.
Treat glass with bird-safe materials so birds see and avoid glass.
Driveways can also cause birds to flush from landscaping into reflective
glazing as vehicles approach.
Ensure routes of escape for birds that are using landscaping along
driveways and access roads.
Take care in routing driveways adjacent to landscaping and reflective
glazing.
Site ventilation grates also present a unexpected danger for birds.
An injured bird that falls onto a ventilation grate with large pores can
become trapped.
Specify ventilation grates with a porosity no larger than 0.8 inches.
13
Cover larger grates with netting.
Never up-light ventilation grates.
Rooftop obstacles such as antennas and media equipment can injure
or kill birds and should be minimized. In poor weather and bright lighting
conditions birds may congregate on and around rooftops.
Co-locate antennas and tall rooftop media equipment to minimize
conflicts with birds.
Utilize self-supporting structures that do not require guy wire supports.
Avoid up-lighting rooftop antennas and tall equipment, as well as
decorative architectural spires. See “Lighting Design” pages 24-25.
Confusing corners with multiple reflections
Birds can fall through grates after hitting windows
20 BIRD-SAFE BUILDING GUIDELINES
Exterior Glass
MOST BIRD COLLISIONS OCCUR at the glazed surfaces of buildings. While circumstances such as lighting and other obstacles do
contribute, glass areas are the primary focus of bird-safe design and retrofit strategies regardless of the overall site, landscape, layout and
massing features. Bird-friendly glass products can contribute to aesthetics, energy efficiency, and effective daylighting. For bird safety,
efforts focus on creating visual markers to make glass visible to birds and minimize reflection of habitat and sky.
CONSIDER VISUAL MARKERS
Objective:
Prevent bird collisions
with glazed surfaces,
while maintaining
transparency for views,
daylighting and passive
environmental control.
White fritted pattern on glass facade at IAC Offices in New York CityInterior shades and exterior film at the Minneapolis Central Library
“Visual noise” is what allows us to see glass. It is created by varying materials, textures, colors, opacity, or other features and helps to break up glass
reflections and reduce overall transparency.
19
Creating these visual markers can alert birds to the presence of glass as an obstacle. This is the most
effective way to mitigate the danger that glass poses to birds.
Utilize etching, fritting, translucent and opaque patterned glass to
reduce transparency and reflection, while achieving solar shading.
(Note: Although fritting is useful for creating visual noise, it is less
effective at reducing reflectance since it is generally applied on the
interior face of the glass.)
Incorporate windows with real or applied divided lights to break up
large window expanses into smaller subdivisions.
Consider applying acid-etched or sandblasted patterns to glass on the
outside surface to “read” in both transparent and reflective conditions.
Create patterns that follow the “hand-print” rule (below).
Use window films featuring artwork or custom patterns permanently
or on a rotating basis.
Low-reflectivity glass has not been sufficiently tested for bird safety but
may prove beneficial in certain installations.
BEST PRACTICES FOR BIRD SAFETY
DID YOU KNOW?
Studies show that small birds will attempt to fly through any opening larger than 4 inches wide or 2 inches tall or about the size of a child’s
handprint oriented horizontally. When creating “visual noise” on or around a window, optimal openings are no larger than a small handprint.
19
NYC AUDUBON
BIRD-SAFE BUILDING GUIDELINES 21
Large expanses of clear exterior glazing do not equate to effective day-
lighting for buildings. In fact, over-glazing can contribute to glare, veiling
reflections, unwanted heat gain, and also bird collisions. Many strategies
used to achieve effective daylighting are compatible with bird safety.
Where appropriate, daylighting strategies such as exterior shading
devices, fritted glass, and diffuse and translucent glass can also help to
prevent bird collisions.
In general, the more untreated glass you have, the greater the risk to
birds, especially on sites that are in predictable migratory and resident
bird areas.
CONSIDER INTEGRATED DAYLIGHTINGCONSIDER INTERIOR AND EXTERIOR TREATMENT
Translucent glass can help balance daylighting and prevent bird collisions
An exterior ceramic framework provides shading and daylighting (New York Times)
Exterior shading or other architectural devices enhance bird safety.
Utilize shading devices, screens, and other physical barriers to reduce
reflectivity and birds’ access to glass.
Incorporate louvers, awnings, sunshades, light shelves or other exterior
shading/shielding devices to reduce reflection and give birds a visual
indication of a barrier.
Consider other highly patterned shading/shielding devices that will
provide visual cues and encourage bird safety.
Interior window treatments can provide visual cues for birds and
reduce both transparency and reflections. They also help reduce light
trespass from buildings. See “Building Operations” page 26.
Design interior window treatments using light-colored solar reflective
blinds or curtains. Partially open blinds during the day.
Close curtains and blinds if evening lighting is utilized.
For best results, consider photo-sensors, timers and other automatic
controls to regulate shading devices, lighting and daylighting.
LEED
Coordinate with LEED Credits
EQ 8.1 and 8.2 Daylight & Views
EA 1 Optimize Energy Performance
WINDOW AREA
Windows constitute
about 25-40 percent
of the wall area of
effectively designed
daylit buildings, an
area very similar to
the windowed area in
non-daylit buildings.
20
22 BIRD-SAFE BUILDING GUIDELINES
DID YOU KNOW?
Unlike humans, birds perceive UV light as a separate color. In fact,
many birds have feather patterns that are invisible to humans. These
patterns help birds distinguish among species and sexes. UV vision
is also important for feeding and for orientation during migration.
Glass products that either reflect or absorb UV wavelengths are
being tested for bird safety but are not yet readily available.
21
BEST PRACTICES FOR BIRD SAFETY
Objective:
Encourage glass
manufacturers to
advance the search
and development of
innovative technologies
that make glass visible
to birds without visually
impairing glass for
humans.
Emerging Technologies
THE ARCHITECTURE AND BUILDING DESIGN INDUSTRY is perhaps best positioned to press for long-term technological
solutions for bird-safety. Encouraging a technological solution would stimulate research and development in the glass industry, and
encourage wide-ranging innovative product development with beneficial economic consequences.
An innovative technological solution would be widely accepted in the design and construction industry, with beneficial economic
consequences, particularly if it minimized aesthetic impacts and was cost-competitive. Developing effective technologies will require
commitment of time and resources along with the support and leadership of glass and construction industry officials.
CONSIDER INNOVATION
Bird-safe glass may involve novel uses of known manufacturing
processes, new/unexplored technologies or even the use of
polycarbonates. Designers and architects can create demand for bird-
safe technology that has stalled in development due to an uncertain
market for these products.
Encourage manufacturers to offer “bird-safe” patterns as stock
products in a variety of finishes for design flexibility (i.e. ceramic frit,
acid etching, laminated LEDs, electrochromic coatings).
Encourage the development of glass that eliminates reflections. The
exterior surface of glass is of primary concern, however all surfaces of
glass reflect habitat to some extent.
Request plastic films, diachronic coatings, and tints for exterior use.
Utilize existing patterning materials such as ceramic frits and acid
etching for exterior use.
Support research on pattern recognition of both humans and birds
to identify patterns that inhibit the fly-through effect while minimally
obstructing human views.
700 nm
600 nm
500 nm
400 nm
300 nm
WAVELENGTH
UV VISIBLE
Differences in human and avian vision have inspired one type of bird-visible glass –
Ornilux Glass – and much ongoing research
Human-visible Bird-visible
ROBERT BLEIWEISS, PROCEEDINGS OF
NATIONAL ACADEMY OF SCIENCES
NYC AUDUBON
BIRD-SAFE BUILDING GUIDELINES 23
Ornilux Glass was recently installed at the Wildlife Conservation Society’s Center for
Global Conservation in Bronx, New York
CONSIDER NEW TECHNOLOGY
The development of an integral glass technology would greatly reduce
the problem of building-related bird mortality without imposing major
aesthetic modifications to contemporary building designs.
Develop glass with integral patterns in the ultra-violet range that will be
visible to birds and not humans.
21
Experiment with particles that can be cast integrally into glass during
the production process.
Encourage the development of other forms of non-reflective tinted or
spectrally selective glass.
LEED
Coordinate with LEED Credits
EQ 8.1 and 8.2 Daylight & Views
ID 1 to 1.4 Innovation in Design
Research and New Product Development
The need for readily-available, cost-effective and aesthetically
acceptable products that effectively deter birds from windows
cannot be overstated. Existing products and strategies, while
developed for other purposes, have great bird-safe potential
and have, in some cases, been used intentionally as such.
Still there remain few materials specifically developed for this
purpose as industry demands have not pushed manufacturers to
meaningful action. It is hoped that ongoing research along with
collaboration between architects, glass/film manufacturers and
bird conservation professionals will yield new products in the
near future.
Ornilux Glass (left) is currently the only commercially available
glass product being marketed as “bird-friendly.” A UV striped
pattern on the inside of the glass increases glass visibility for
birds while remaining relatively unobtrusive for people.
Many consider UV coated glass and films to be an ideal solution
because of their potential to deter birds while leaving the
appearance of glass largely unchanged. Recent research by
Dr. Daniel Klem of Muhlenberg College explored the use of
a window film with alternating UV reflecting and absorbing
stripes and found it highly effective as a deterrent to collisions.
22
Ongoing work in Austria by Martin Roessler has focused on
finding which patterns, when applied to glass, are most effective
in deterring birds while simultaneously requiring the least
coverage.
23
In the end, the development of effective bird-friendly products
requires the will on the part of building designers, owners
and managers to demand and test new and existing materials
in real-life conditions. A number of inspiring case studies
exist (see pages 32-36) and ongoing work with glass and film
manufacturers may soon yield readily available products that
satisfy both birds and people.
CHRISTINE SHEPPARD
24 BIRD-SAFE BUILDING GUIDELINES
BEST PRACTICES FOR BIRD SAFETY
Lighting Design
Objective:
Undertake strategies
to reduce light trespass
from buildings,
particularly during
migration seasons.
REDUCING EXTERIOR BUILDING AND SITE LIGHTING has been proven effective at reducing nighttime migratory bird
collisions and mortality. At the same time, such measures reduce building energy costs and decrease air and light pollution. These guidelines
encourage efficient design of lighting systems as well as operational strategies to reduce light trespass from buildings, particularly during
migration seasons.
CONSIDER EXTEROR LIGHT TRESPASS
PREFERRED DISCOURAGED
Light pollution is largely a result of inefficient exterior lighting.
Eliminate light directed upwards by attaching cutoff shields to street-
lights and external lights.
Highlight building features without up-lighting.
Reduce the amount of light that spills outside areas where it is needed
for safety and security.
Maximize the useful light directed to targeted areas.
Eliminate the use of spotlights and searchlights during bird migration.
DID YOU KNOW?
Red lights that don’t flash are most attractive (and therefore
deadly) to birds. Instead, use flashing white or non-flashing blue or
green lights.
24
Direct exterior lighting downwards and adhere to Lights Out Guidelines
Light advertising from above to reduce the light projected skyward
Lighting diagrams courtesy
of the City of Toronto
BIRD-SAFE BUILDING GUIDELINES 25
CONSIDER INTERIOR LIGHT TRESPASS
Light trespass from within buildings can be reduced through design and
operational changes.
Design lights to shut off using automatic controls, including photo-
sensors, infrared and motion detectors. These devices generally pay for
themselves in energy savings within one year.
Reduce the need for extensive overhead lighting.
Encourage the use of localized task lighting and shades.
Reduce perimeter lighting and/or draw shades wherever possible.
PREFERRED DISCOURAGED
Preferred lighting designs project
light downward, reducing waste
and light pollution.
Discouraged lighting designs cause
spill light to be directed into the
sky where it is not needed.
LEED
WASTED LIGHT
Light pollution is
largely the result of
bad lighting design,
which allows artificial
light to shine outward
and upward into the
sky, where it’s not
wanted, instead of
focusing it downward,
where it is.
National Geographic,
November 2008
Coordinate with LEED Credits
SS 8.0 Light Pollution Reduction
EQ 6.1 Controllability of Systems: Lighting
EA 1 Optimize Energy Performance
26 BIRD-SAFE BUILDING GUIDELINES
BEST PRACTICES FOR BIRD SAFETY
Building Operations
Objective:
Further reduce light
trespass through
operational procedures.
Implement monitoring
programs to determine
bird-collision areas
and success of light
reduction.
GREAT STRIDES CAN BE MADE to reduce light pollution from buildings during normal building operations. These strategies
apply to new and existing buildings and often require the commitment and participation of both building owners and users. In addition,
implementing bird-collision monitoring practices will help identify problem areas of a building or site.
CONSIDER DAYTIME CLEANING
CONSIDER LIGHTS OUT
CONSIDER BIRD MONITORING
Cleaning during normal work
hours is becoming more common
and can reduce bird mortality and
light pollution. Such a schedule
reduces energy consumption
and enhances security. If cleaning
during the day is not an option:
Complete nightly maintenance
activities before midnight or
earlier.
Instruct cleaning crews to work
down from the upper stories,
turning off lights as they go.
Implementing daily bird-collision
monitoring provides valuable
information for science and for
prioritizing building retrofits.
Sweep the building perimeter,
setbacks, and roof daily for
injured or dead birds.
Note specific times, dates and
locations of birds that are found.
Work with Project BirdSafe to
document all bird deaths and
assist injured birds. Most birds
are protected by the Migratory
Bird Treaty Act of 1918.
Lights Out programs are city or state-wide initiatives designed to
reduce light pollution and bird mortality. In Minnesota, Lights Out
is coordinated by Audubon Minnesota’s Project BirdSafe using these
parameters:
Building owners and facility managers extinguish all unnecessary
exterior and interior lights from at least midnight to dawn especially
during bird migration periods:
(Spring) March 15 to May 31
(Fall) April 15 to August 31
Priority lights include: exterior architectural lighting; interior lighting
especially on upper floors; lobby and atrium lighting.
Clean buildings from the top down The iconic Wells Fargo building was the first to sign on to Lights Out in Minnesota
Bird monitoring pinpoints problem areas
NYC AUDUBONNYC AUDUBON
It is also recommended that building managers work with Project
BirdSafe to monitor the effectiveness of Lights Out programs by
tracking bird collisions and mortality rates. In addition, tracking light
emission reductions and cost savings can provide valuable statistics.
Sign on to Lights Out at mn.audubon.org
BIRD-SAFE BUILDING GUIDELINES 27
Comprehensive Site Strategy
Blue-winged Warbler
The overall rate of collisions at a given building is based on
many variables. Solutions can be implemented at the initial
design stage or with modifications or operational changes.
The following examples represent a comprehensive bird-
friendly site strategy.
A. Treatment applied to glass projecting visual markers to
make it visible to birds
B. Task lighting in use after dark
C. Blinds drawn after dark
D. Lights off after work hours
E. Awning blocks reflections on lobby windows from above
F. Glass effectively angled to reduce strike angle and project
reflections downward
G. Bird-friendly site ventilation grates
H. Use of lighting fixtures effectively projecting light
downward
MIKE LENTZ
28 BIRD-SAFE BUILDING GUIDELINES
BEST PRACTICES FOR BIRD SAFETY
Modifications to Existing Buildings
Objective:
Undertake alterations
or retrofits to buildings
with high incidence of
bird collisions.
IMPLEMENTING BIRD-SAFE STRATEGIES for new buildings
provides important opportunities to protect birds through design.
However, new buildings represent only a small fraction of those
responsible for bird fatalities. Retrofitting existing buildings is an
important challenge and opportunity to help reduce bird-building
collisions. Systematic site analysis and bird monitoring can dictate
priorities for building modifications, programmatic enhancements
and landscape adjustments to benefit birds.
CONSIDER YOUR BUILDING AND SITE
This checklist summarizes conditions that contribute to bird injury and
mortality. It may be used towards an initial evaluation of new and existing
buildings for potential problems.
Region
Within Migratory Route
Proximate to Migratory Stopover Destination
Locale
Near Attractive Habitat Areas
Dense Urban Context (Reduced Sky Visibility)
Fog-Prone Area
Site
Nearby Trees and Shrubs
Adjacent to Grassy Meadows
Water Features/Wetlands
Façade Glass Coverage (Overall Percentage)
Less than 20%
Between 20 and 35%
Between 35 and 50%
Over 50%
Special Features
Unbroken Glass Expanses at Lower Levels
Courtyard(s)
Transparent Corners
Glazed Passageways
Glazed Site Dividers/Bus Shelters
Glazing Characteristics
Tinted
Reflective
Mirrored
Dusk and Night-Time Illumination
External Facade Up-Lighting
Non-Cut-Off Exterior Lighting
Spill of Interior Lighting
Other Building Elements
Antennae
Spires
Guy-Wires
LEED
Coordinate with LEED Credits
EQ 8.1 & 8.2 Daylight & Views
EA 1 Optimize Energy Performance
Specific bird-collision problem areas can be identified and targeted for
intervention during routine building maintenance activities.
Analyze your building facility and site to determine the presence and
extent of bird collision hazards. Use checklist at right.
Integrate bird monitoring efforts with daily maintenance. See “Bird
Monitoring” page 26.
Undertake retrofits and other strategies to reduce bird collisions.
Continue monitoring building(s) to determine the effectiveness of
retrofits in reducing or eliminating bird mortality.
Identify problem areas
CHECKLIST OF BIRD COLLISION LIABILITIES
BIRD-SAFE BUILDING GUIDELINES 29
CONSIDER MODIFICATIONS
Create a physical barrier at notably hazardous windows to deter birds
or reduce the momentum of their impact.
Install netting over problem windows.
Mount exterior coverings or insect screens.
Incorporate latticework, artwork, shading or shielding devices outside
glass.
Make interior changes to indicate glass barrier or remove attractants.
Install and operate window blinds, shades, or curtains to hide interior
views of plants and hiding places.
Close curtains or blinds after dark if the interior is illuminated.
Relocate or shield interior plantings, water sources, and other features
that may be contributing to bird collisions.
Install artwork or screening just inside glass to be clearly visible from
outside at all angles.
Retrofit problematic windows and facades which cause birds to
attempt to fly through glass or fly to reflections of habitat or sky. While
creating visual barriers for birds, these strategies can simultaneously
improve daylighting, save on energy costs, and enhance aesthetics.
Install transparent or perforated patterned, non-reflective window films
that make glass visible to birds.
Consider painting, etching or temporarily coating collision prone
windows to make them visible to birds.
Add decorative exterior screening and/or solar shading devices,
including louvers, awnings, sunshades, and light shelves.
Consider re-glazing existing windows that experience high rates of bird
collisions with translucent, etched, frosted, or fritted glass.
Consider replacing large existing windows with multiple smaller units,
divided lights, translucent, or opaque sections.
Window film eliminated collisions in this courtyard at Patuxent Refuge in Maryland Window screening by Birdscreen installed at Rowe Audubon Sanctuary in Nebraska
If monitoring reveals bird collisions, building retrofits usually focus on eliminating reflections and fly-through effects or creating physical barriers.
Many design strategies for new buildings and building operational changes (pages 16-26) can be used to improve existing buildings for birds.
NYC AUDUBON
LAURA ERICKSON
30 BIRD-SAFE BUILDING GUIDELINES
BEST PRACTICES FOR BIRD SAFETY
Creative use of graphics can serve program needs and simultaneously
create glazing opacity.
Utilize decorative window films and banners to announce programs,
enhance aesthetics, and display artwork.
Consider rotating art displays in problematic windows during each
migration season or on a more permanent basis. Such displays should
create enough visual noise to be seen clearly from outside the glass at
all angles.
Research public art programs in your area as a way of encouraging
window art displays.
CONSIDER OPERATIONAL CHANGES
In addition to incorporating bird monitoring with routine maintenance
and security operations, an existing building that is experiencing bird
collisions can consider other operational changes.
Institute the practice of cleaning during the day to reduce light pollution
and energy consumption, enhance security, and save money.
Educate building users about the dangers of light trespass for birds.
Incorporate lighting design changes to reduce spill light and automate
lighting systems.
Adopt a Lights Out policy for building and site.
Utilize minimum wattage fixtures to achieve required lighting levels.
CONSIDER LANDSCAPE ENHANCEMENTS
Generally the most effective way to solve bird-collision issues is by
dealing with reflective or transparent glass issues as outlined on pages
20-21. Sometimes, it is possible to alter landscaping to improve bird
safety at specific sites.
Consider moving or shielding habitat that is being reflected in windows
or is a lure from the other side of clear glass (fly-through effect).
To address problematic glass windows, consider planting or re-locating
trees and shrubs close to the building within a maximum of three feet.
This planting strategy can block access to habitat reflections and birds
alighting in these trees will not have the distance to build momentum
on a flight path towards the glass. Such plantings can also provide
beneficial summertime shading and reduce cooling loads.
Create a green screen for foliage to grow adjacent to building exterior
offering shading and visibility to birds.
See “Site and Landscape Design” pages 16-17.
Dayshift cleaning
cost savings are
estimated at 4-8% per
year. That translates
to $145,790 –
$291,581 for a
building like the IDS
Center in Minneapolis
or up to $10 million
a year if incorporated
throughout the city.
25
LEED
Coordinate with LEED Credits
SS 8.0 Light Pollution Reduction
EQ 6.1 Controllability of Systems: Lighting
SS 5.1 Protect or Restore Habitat
CONSIDER PROGRAMMATIC OPPORTUNITES
Community art displays, like this one at St. Paul Travelers, can reduce bird collisions
BIRD-SAFE BUILDING GUIDELINES 31
CONCLUSION
Hope for the Future
BIRDS HAVE CAPTURED OUR HEARTS throughout history.
We are captivated by their songs, their colors and their unlikely
feats of endurance during migration. Birds have penetrated our arts,
literature and even hijacked our leisure time. And birds are indicators
of the state of our world. We all have a stake in their future.
While the challenges we all face in protecting biodiversity seem
daunting, solutions abound. With commitment we can halt and
reverse the decline of birds and their habitats. Reducing hazards
to birds navigating our built environment is one way to make a
positive difference. Armed with the knowledge and best practices
included in these guidelines, we can incorporate bird-safe strategies
in our approach to new construction. And, with examples of other’s
successes, we can modify existing structures to reduce their toll on
birds. In either case we need to take action.
We have great potential in our urban centers to engage people – from
residents to community leaders, from students to executives – in
making changes that help us all co-exist with nature. Being “green”
is now a pervasive desire expressed in our product choices in the store,
our design choices in our buildings and in our guiding principles as
a culture. Incorporating the needs of birds is a logical progression in
our concept of sustainable design and development. Working across
disciplines using intellect and creativity can yield untold benefits for
people and for birds in the future.
Architects, designers and biologists working together are our best hope for the future
A polycarbonate core makes this glass visible to birds (IIT Student Center, IL) Warblers like this Chestnut-sided will benefit from our creativity and collaboration
NYC AUDUBON
LAURA ERICKSON
32 BIRD-SAFE BUILDING GUIDELINES
The Minneapolis Central Library incorporates bird-safe design
techniques in several ways. Its variegated and curtained facade presents
an identifiable pattern to birds, while an indigenous shale and birch
garden at the building’s north perimeter filters views to and from the
main level reading rooms. This technique of planting very close to a
building facade, in addition to providing shade, prevents incidents of
fatal bird strike. Birds cannot see reflections cast upon the glass and are
less likely to develop fatally high speed collision rates due to the close
proximity of planting to glass. The Library’s central atrium features
angled glass, a dramatic architectural feature that also greatly eliminates
reflections of habitat and sky from most angles. The likelihood of fatal
collisions at this angle is also greatly reduced.
MINNEAPOLIS CENTRAL LIBRARY - Minneapolis, MN
▪ Architects: Pelli Clarke Pelli Architects ▪ Landscape design: Coen + Partners ▪ Architectural Alliance
CASE STUDIES
New Construction
Solution: Visual
Noise
Solution: Vegetation
near building
Problem: Reflection
Problem:
Transparency
BIRD-SAFE BUILDING GUIDELINES 33
AQUA TOWER - Chicago, IL
▪ Architects: Studio Gang Architects
Solution: Screen /
scrim / fritting
Solution: Visual
Noise
Problem: Reflection
Problem:
Transparency
The Aqua Tower is a new Chicago landmark and the winner of the 2009
Emporis Skyscraper Award for high-rise architecture. This 82-story
residential and commercial tower is a departure from the modern
sheer glass skyscraper, incorporating an undulating pattern of exterior
terraces which create an organic façade. Architect Jeanne Gang and her
team not only aspired to create the natural look of eroded cliffs with
the wavering terraces, they also convinced the developer to use fritted
glass with a grey dot pattern and picketed railings on the balconies, all to
enhance bird-safety. Gang has long been an advocate of bird-safe design
and has incorporated bird-safe strategies in a number of her projects.
studiogang.net
This renovation and 75,000 square foot addition to an existing science
facility was planned to create a series of outdoor courtyards that took
advantage of the site’s beneficial topography and mature trees. Sensitive
to the liabilities of extensive glazing placed near attractive landscapes,
the College and its architect consulted ornithologist Daniel Klem who
proposed patterning portions of the glass at potential collision “hot
spots.” After testing several configurations, the designers decided to use
a glass with a ceramic frit matrix at locations deemed susceptible to bird
collision. Swarthmore engineering professor Carr Everbach designed a
“thump sensor” webcam for installation next to windows to detect bird
collisions. According to Klem, collisions have been reduced significantly
to a mere one or two a year, giving Swarthmore confidence to extend
the treatment to other campus buildings.
archnewsnow.com/features/Feature171.htm
SWARTHMORE COLLEGE UNIFIED SCIENCE CENTER - Swathmore, PA
▪ Architects: Helfand Architecture and Einhorn Yaffee Prescott ▪ Landscape design: Gladnick Wright Salameda; ML Baird & Co.
STUDIO GANG ARCHITECTSBIRDSANDBUILDINGS.ORG
34 BIRD-SAFE BUILDING GUIDELINES
This Town building with reflective glass and a solarium entrance has
long been a site of bird strikes. The environment is one of six strategic
goals for Markham Council. One of the town Councilors, Valerie Burke,
championed bird-friendly buildings and design as an integral aspect of
the environment. Town staff worked with FLAP and The Convenience
Group to develop and apply a patterned window film to address the bird
collision problem.
This is the first application of a bird-friendly window film on a municipal
building in the Greater Toronto Area. Initial results indicate the film is
very effective in eliminating collisions. This application could serve as a
highly influential tool for convincing building managers and governments
at all levels to make their structures bird-friendly.
flap.org/markham.htm
TOWN OF MARKHAM – Markham, Ontario, Canada
▪ The Convenience Group ▪ The Fatal Light Awareness Program (FLAP)
Retrofitting Existing Buildings
This green building demonstration project, completed in 2001, was built
adjacent to a wetland. Its glazed elevations, while affording intimate
views of the natural surrounding, caused bird fatalities. The problem was
successfully remedied through a partial retrofit with fine netting.
CUSANO ENVIRONMENTAL EDUCATION CENTER – Philadelphia, PA - John Heinz National Wildlife Refuge
Solution: Use
of plastic films,
diachroic coatings
and tints on facade
Problem: Reflection
Solution: Screen /
scrim / fritting / net
Problem: Reflection
Problem:
Transparency
CASE STUDIES
FLAPBILL BUCHANAN
BIRD-SAFE BUILDING GUIDELINES 35
New York City Audubon’s Project Safe Flight volunteers identified the
six-story Morgan Mail Processing Facility as a high-collision site. The
building had a full city block of black reflective spandrel panels facing a
park. Birds in the park were hitting the building because of the habitat
they saw reflected in Morgan Mail’s façade. Alerted to NYC Audubon’s
mortality findings, postal officials worked with SurfaceCare to resolve
this problem. They applied a vinyl black matte signage film to the
exterior on all 440 (8’ by 5’) panels of glass (left, during installation).
The solution was a success and the building went from being one of New
York’s deadliest buildings for birds to one of its safest.
nycaudubon.org
surfacecareusa.com
MORGAN MAIL – Manhattan, NY
▪ SurfaceCare ▪ New York City Audubon
Solution: Use
of plastic films,
diachroic coatings
and tints on facade
This glass pavilion positioned directly adjacent to Lake Michigan encloses
the Adler Planetarium’s exit stair. Noting that it was causing bird death
and injury, the Museum maintenance staff sought to address the problem
first through the application of traditional bird decals. When that
solution proved ineffective, they subsequently upgraded to this painted
striping system for the glass fronting the lake, which has largely solved
the problem.
ADLER PLANETARIUM – Chicago, IL
Solution: Screen /
scrim / fritting
Problem:
Transparency
Problem: Reflection
NYC AUDUBONBIRDSANDBUILDINGS.ORG
HealthPartners signed on to participate in the Lights Out program
in Minnesota as soon as they heard about it in the local media. They
embraced Lights Out and incorporated it along with other facility-wide
energy saving measures. Because they are a healthcare company and
house a department of 24 hour on-call phone agents, HealthPartners did
have certain interior lights in use all night long. In response, the company
moved those employees to the lower level of the building and into the
interior in order to allow the perimeter lights to be extinguished at
night. HealthPartners has also hosted an informational session about
birds for their employees and monitors the building for birds. In fact,
they have made bird monitoring part of their landscaping contract and
work with Project BirdSafe to document and take care of any birds they
find.
HEALTHPARTNERS – Bloomington, MN
Building Operations
Solution: Lights out
Solution: Lights out
Problem: Beacon
effect, illumination
Problem: Beacon
effect, illumination
Problem: Reflection
STATE OF MINNESOTA – Lights Out Law
In May 2009 the State of Minnesota passed legislation requiring
occupants of state-owned or state-leased buildings to attempt to
reduce dangers posed to migrating birds by turning off unnecessary
lights between March 15 to May 31 and August 15 to October 31 from
midnight to dawn. The law allows the Commissioner of Administration
to adopt policies for the practical implementation of this law for prisons
and other facilities that depend upon night lighting. The Lights Out law
was sponsored by State Representative Phyllis Kahn (DFL – Minneapolis)
and inspired by Audubon Minnesota’s Lights Out program.
Chapter 101, Article 2, Section 54 [16B.2421] BIRD-SAFE BUILDINGS
HENNEPIN COUNTY – Dayshift cleaning
Starting in March 2010 about half of Hennepin County Minnesota’s
63 buildings transitioned to day shift cleaning to save on electricity,
heating and cooling costs. Savings are expected to be at least $100,000
annually. With this move, Hennepin County joined a trend that has been
popular in the private sector for some time. While day-shift cleaning is
generally initiated as a cost-savings measure, it has many other positive
side-effects for workers and for the environment. The reduction in
greenhouse gas emissions and decrease in light pollution from interior
lights make daytime cleaning a very positive move for the birds.
bluegreenalliance.org/press_room/press_releases?id=0064
36 BIRD-SAFE BUILDING GUIDELINES
CASE STUDIES
BIRD-SAFE BUILDING GUIDELINES 37
Products and Innovations
RESOURCES
Translucent and Decorative Glazing:
3Form (3-form.com)
Bendheim (bendheim.com)
Cabont Nanogel/Aerogel (cabot-corp.com)
Goldray Industries (goldrayindustries.com)
Kalwall (kalwall.com)
Major Industries (majorskylights.com)
Schott (us.schott.com)
TG P/Pilkington Profilit (tgpamerica.com)
Viracon (viracon.com)
Decorative Ceramic Fritting:
Goldray Industries (goldrayindustries.com)
Oldcastle Glass (oldcastleglass.com)
Viracon (www.viracon.com)
PPG Industries (ppg.com)
Applied Window Films and Spectrally Selective Glass:
Arnold Glas, Ornilux (glaswerke-arnold.de)
Collidescape (fetchgraphics.com)
Solutia / CPFilms Inc. (cpfilms.com)
SurfaceCare USA (surfacecareusa.com)
The Convenience Group (conveniencegroup.com)
U.S. Dept. of Energy (eere.energy.gov)
Electrochromic Glass:
Sage Electrochromics Inc. (sage-ec.com)
Smart Glass International (smartglassinternational.com)
While product innovations continue to emerge, many currently available products have potential bird-safety features even if they were
developed for other purposes such as balanced daylighting, innovative aesthetics, building safety and security, and energy efficiency.
The following material sources may contribute to bird safety for new or existing buildings. Products and manufacturers listed below are for
information only, and are neither recommended nor endorsed by Audubon Minnesota and its Project BirdSafe partners.
Architectural Metal Mesh:
Cambridge Architectural (cambridgearchitectural.com)
GKD Metal Fabrics (gkdmetalfabrics.com)
Johnson Screens (johnsonscreens.com)
Building-Integrated Photovoltaics:
PowerFilm (powerfilmsolar.com)
Uni-Solar (www.uni-solar.com)
ARCH Aluminum and Glass (archaluminum.net)
Exterior Louvers and Sunscreens:
Hunter Douglas Contract (hunterdouglascontract.com)
Industrial Louvers Inc. (www.industriallouvers.com)
Nysan Shading Systems (nysan.com)
Savannah Trims (suncontrolers.com)
Façade-Integrated LEDs:
Cambridge Architectural (cambridgearchitectural.com)
GKD Metal Fabrics (gkdmetalfabrics.com)
Schott (us.schott.com)
Window Treatments and Banners:
Banner Creations (bannercreations.com)
Biographix (rainierdisplays.com/biographix.html)
Exterior Coverings, Nettings, Screening:
Bird-B-Gone (birdbgone.com)
Nixalite bird exclusion netting (nixalite.com)
StealthNet (birdbarrier.com)
TopRite Netting (cutlersupply.com)
JIM WILLIAMS
Tennessee Warbler
38 BIRD-SAFE BUILDING GUIDELINES
Local Resources
RESOURCES
Bird Collision Monitoring: Project BirdSafe volunteers conduct
surveys daily during migration along established research routes.
Surveys can also be started at any interested building in conjunction
with the project. Surveys involve collection of injured and dead birds
resulting from building collisions in accordance with established bird
monitoring protocols. Visit mn.audubon.org/birds-science-education/
project-birdsafe
Important Bird Areas (IBA): This international conservation
effort identifies, designates, monitors and conserves the most valuable
habitats for birds. An Important Bird Area (IBA) is a site that provides
essential habitat for breeding, wintering, and migrating bird species.
In Minnesota the IBA program is a joint effort between Audubon
Minnesota and the Minnesota DNR Non-game Wildlife program. Visit
mn.audubon.org/birds-science-education/important-bird-areas or www.
dnr.state.mn.us/iba/
Christmas Bird Count (CBC): This one-day annual event has been
conducted for over a century. The CBC database contains more than
100 years of data on winter bird populations across the Americas. In
Minnesota the Christmas Bird Count is done in partnership with the
Minnesota Ornithologists' Union. Visit moumn.org/CBC/
IN MINNESOTA a variety of organizations have established programs related to bird-collision monitoring, bird counting, population
mapping and identification of key habitat including Important Bird Areas. Data from these programs can be used in developing natural
resources inventories for development projects. Corporations can also get involved in these efforts as a contribution to their community and
for the enrichment of their employees.
Minnesota Breeding Bird Atlas: Starting in April 2009, volunteers
began documenting evidence of breeding birds throughout the state.
The project will continue through the summer of 2013 and will result
in a detailed atlas of all breeding bird species in the state. The presence
and abundance of birds provides valuable information about the health
of our environment. This atlas will be an important baseline for future
surveys. Visit mnbba.org.
The Wildlife Rehabilitation Center (wrcmn.org) and The Raptor
Center at the University of Minnesota (raptor.cvm.umn.edu)
provide emergency medical care for injured birds and animals from all
over Minnesota.
The Red-Headed Woodpecker Recovery Project
(redheadrecovery.org), Minnesota Purple Martin Conservation
Project (mnmartin.org) and Bluebird Recovery Program (bbrp.
org) are species-specific conservation programs that may be applicable
to corporate campuses in the appropriate habitats.
Great Backyard Bird Count: This annual Presidents’ Day Weekend
event is an opportunity for volunteers to count the birds in their
backyards and beyond. Visit birdsource.org/gbbc.
Local organizations, programs and citizens track bird populations and protect bird species like the Ovenbird, Eastern Bluebird, Baltimore Oriole, Ruby-throated Hummingbird, and White-throated Sparrow
JIM WILLIAMS
REBECCA FIELD
JIM WILLIAMS
JIM WILLIAMS
REBECCA FIELD
BIRD-SAFE BUILDING GUIDELINES 39
References
1. Klem, Daniel, Jr. (1989). Bird-Window Collisions. The Wilson Bulletin, 101(4), 606-620.
muhlenberg.edu/main/academics/biology/faculty/klem/ACO/Research_Papers.htm
2. Buildings, Benchmarks & Beyond: The State of Minnesota Sustainable Building Guidelines
(B3-MSBG). msbg.umn.edu
3. Leonard, Jerry. (2008). Wildlife Watching in the US: The Economic Impacts on National
and State Economies in 2006. Arlington, VA: US Fish and Wildlife Service.
4. Carver, Erin. (2009). Birding in the United States: A Demographic and Economic
Analysis. Arlington, VA: The US Fish and Wildlife Service.
5. Longcore, Travis, Ph.D. et al. (2005). Scientific Basis to Establish Policy Regulating
Communications Towers to Protect Migratory Birds. WT Docket No. 03-187, Federal
Communications Commission Notice of Inquiry (Feb 14,2005).
6. US Energy Information Administration, Office of Integrated Analysis and Forecasting,
December 2008. Emissions of Greenhouse Gases in the United States 2007, (Report
#: DOE/EIA-0573(2007)). US Department of Energy: Washington, DC. eia.doe. gov/
oiaf/1605/ggrpt/pdf/0573(2007).pdf
7. North American Bird Conservation Initiative, U.S. Committee. (2009). The State of the
Birds, United States of America, 2009. Washington, DC: U.S. Department of Interior.
stateofthebirds.org/
8. The exception seems to be pigeons, starlings and sparrows that do not collide with
buildings in significant numbers due to their high level of adaptation to urban
environments.
9. International Dark-Sky Association Newsletter Issue #67. (2006). The Cost of Light
Pollution. data.nextrionet.com/site/idsa/nl67.pdf
10. Ogden, Lesley J. Evans. (1996). Collision Course: the Hazards of Lighted Structures and
Windows to Migrating Birds. Published by World Wildlife Fund Canada and the Fatal
Light Awareness Program. flap.org/new/ccourse.pdf
11. The world’s tallest structure is the 2,720 ft. tall Burj Khalifa in Dubai, United Arab
Emirates which opened 4 January 2010. It is taller than any other man-made structure
ever built. The two tallest buildings in the USA are the Willis Tower in Chicago (formerly
Sears Tower) at 1450 ft and the Empire State Building in New York City at 1250 ft. The
tallest Minnesota building is the IDS Tower at 792 ft. en.wikipedia.org/
12. metrocouncil.org/OnCourse2008/presentations/CompPlanning.pdf
13. City of Toronto Green Development Standard. (2007). Toronto Bird-Friendly
Development Guidelines. City Planning, Toronto, Ontario, Canada. toronto.ca/lightsout/
pdf/development_guidelines.pdf
14. City of Toronto Biodiversity Series. (2009). Birds of Toronto: A Guide to their
Remarkable World.
15. Klem, Daniel, Jr. (1989). Bird-Window Collisions. The Wilson Bulletin, 101(4): 606-620.
16. Gelb, Yigal and Nicole Delacretaz. (2009). Windows and Vegetation: Primary Factors in
Manhattan Bird Collisions. Northeastern Naturalist, 16(3): 455-470.
17. Klem, Daniel, Jr. (1990). Collisions Between Birds and Windows: Mortality and
Prevention. Journal of Field Ornithology, 61(l): 120-128.
18. Klem, Daniel, Jr., et al. (2004). Effects of Window Angling, Feeder Placement, and
Scavengers on Avian Mortality at Plate Glass. Wilson Bulletin, 116(1): 69–73.
19. Doeker, Randi. Bird and Buildings: Creating a Safer Environment. Birds & Buildings
Forum. birdsandbuildings.org/
20. Effective daylighting is a result of integrated design and brings together multiple
disciplines in the planning of indoor spaces. See daylighting.org
21. Burkhardt, D. and Maier, E. (1989). The Spectral Sensitivity of a Passerine Bird is highest
in the UV. Naturwissenschaften 76: 82-83.
22. Klem, Daniel Jr. (2009). Preventing Bird-Window Collisions. The Wilson Journal of
Ornithology, 121(2): 314-321.
23. Rössler, Martin, Wolfgang Laube and Phillip Weihs. (2007). Avoiding Bird Collisions with
Glass Surfaces: Experimental investigations of the efficacy of markings on glass panes
under natural light conditions in Flight Tunnel II. Biological Station Hohenau-Ringelsdorf.
24. Gehring, Joelle, Paul Kerlinger and Albert Manville. (2009) Communication towers,
lights and birds: successful methods for reducing the frequency of collisions. Ecological
Applications: 19(2), 505-514.
The Phillips Company has developed new lighting products for off-shore oil platforms to
reduce bird mortality at those structures. origin.newscenter.philips.com/about/news/
news/20070824_bird_lighting.page
25. Young, Jim, Kelly Schwinghammer, Eric Steen, and David Zaffrann. (2010). Clean Sweep:
How a new approach to cleaning commercial buildings in the Twin Cities can protect
our health and the environment while securing jobs and saving money. Minneapolis, MN.
Published by SEIU Local 26 and the Blue Green Alliance.
Online Resources
The American Bird Conservancy (abcbirds.org)
Birds & Buildings Forum (birdsandbuildings.org)
Chicago Audubon (lightsout.audubon.org)
Chicago Bird Collision Monitors (birdmonitors.net)
The Fatal Light Awareness Program (flap.org)
Muhlenberg College – Acopian Center for Ornithology (aco.muhlenberg.edu/aco.htm)
New York City Audubon (nycaudubon.org)
DISCLAIMER: This publication is presented in good faith and is intended for general guidance
only. The material was drawn from many sources; every effort was made to cite the sources and
any omissions are inadvertent. The contents of this publication are not intended as professional
advice. The authors, National Audubon Society, Audubon Minnesota, and NYC Audubon make
no representation or warranty, either express or implied, as to the completeness or accuracy
of the contents. Users of these guidelines must make independent determinations as to the
suitability or applicability of the information for their own situation or purposes; the information
is not intended to be a substitute for specific technical or professional advice or services. In no
event will the publisher or authors be responsible or liable for damages of any nature or kind
whatsoever resulting from the distribution of, use, or reliance on the contents of this publication.
JIM WILLIAMS
Black and White Warbler
AUDUBON MINNESOTA
2357 Ventura Drive, Suite 106
Saint Paul MN 55125
651.739.9332
mn.audubon.org
Printed on 10% post-consumer recycled paper
