Birds & Glass

The Issue

Given the hundreds of millions of birds killed every year due to collisions with glass on human-built structures, bird window strikes are a major factor in the decline of bird populations globally. Additionally, the collisions subject these delicate animals to an untimely, cruel and gruesome death. This is caused by glass on all types of structures—from tall skyscrapers to home windows to railings. Glass collisions do not discriminate between species, sex, age, geography or seasons. It is a constant threat to all birds.

It is both the reflective and transparent characteristics of glass that make windows and facades dangerous for birds. They see reflections of vegetation and sky and respond to it as if the reflections are reality. Birds might also see a flight path through a window, a glazed building corner or glass walkway (the “passage effect”). There is no barrier perceived and they fly into the glass causing instant death or severe head trauma that they eventually die from, or because they are injured, fall prey to scavengers.

The Challenge

Glass as a design element has many purposes, including providing a feeling of openness, to bring natural light into a building, while also providing thermal protection from heat and cold. Advances in glass technology make it an ideal building and design material. This along with green building practices that focus on energy efficiency through the use of natural light add up to more and more glass being utilized in architecture, which translates to increasingly dangerous conditions for birds.

Over recent years, awareness of and education about the collisions issue has grown. The call for the implementation of bird-friendly design considerations has traction not only in the architectural and building community, but also in state and city governments. Avian advocacy efforts have given rise to many cities and states adopting voluntary, sometimes mandatory, bird-friendly design practices, including the use of bird-friendly glazing treatments and lighting elements. Additionally, U.S. Green Building Council’s LEED program has an innovation credit in its rating system, Pilot Credit 55: Bird Collision Deterrence. This has established an important incentive for architects and building owners to adopt bird-friendly design methods.

The Solution

Because birds, unlike people, do not have the capability to read contextual architectural clues alerting to the presence of a clear piece of glass, something must be done to create a “visual signal” on the glass - patterns that birds can recognize.

There are many strategies to create these bird-friendly patterns for both existing and new glass, but it is important to keep in mind the “2 x 4 rule” which states that patterns should not be spaced more than 2 inches apart horizontally and 4 inches apart vertically to be effective at deterring collisions. Visit our Resources section for more information.


The 3 Pillars Approach

ARNOLD GLAS is committed to support, what we call the 3 Pillars of Bird-Friendly Architecture: Awareness and Education about the bird window collisions issue, making Bird-Friendly Glazing Solutions available, and Creating Behavioral Change in architectural design and building practices. These three things are essential elements in facilitating change, and representatives from each pillar must cooperate, for without one the others will not achieve their goal.

ORNILUX has been granted permission to use this image by artist, Miranda Brandon from her body of work titled, Impact. Her images have been exhibited nationally in museums, print and online.  Following is a statement from the artist:

"In 2013, artist Miranda Brandon began making images concerned with issues of how space is shared between human and nonhuman species. Volunteering for the Audubon, Brandon photographed birds that meet untimely deaths due to window collisions. The large-scale photos call attention to these frequent but often unknown tragedies, giving voice to these birds' plight and acknowledging the loss of their lives."


Miranda Brandon

Visit Miranda's site

General Management/Sales

Stefan Goebel

+1 857 294 7768


Project Management & Sales

David C. Johnson

+1 781 732 1292

U.K. Inquiries

Dave Wyatt / EU Glass

0044 208 854 2878 / 0044 781 504 4434

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