This cedar waxwing was killed by a confusing window reflection.
The Portland-Vancouver metropolitan area is famed as one of the most wildlife-friendly areas in the nation, and in many ways that reputation is well-deserved. We consistently vote to invest in a network of regional parks that provides both high-value ecological habitat and creates opportunities for people to connect with nature. We clamor to certify our yards as backyard habitats that help knit parks and greenspaces together for birds and wildlife (3,000 yards and counting!). And we turn out in droves every September to welcome migrating Vaux’s swifts to their chimney roost at Chapman Elementary School in Northwest Portland.
Transparent and reflective glass facades pose hazards for birds.
At the same time, our urban region is growing like never before, and with that gold rush-paced development, our built landscape is getting taller, glassier and brighter. And while the sustainable building movement is beginning to think beyond the old status quo of energy-efficient buildings, we need strong leadership to ensure that, as a region, we are on a trajectory to protect the ecological function of our cities, including thoughtfully mitigating hazards for birds where they occur in built landscapes.
Window collisions are among the top conservation threats to birds, third only to habitat destruction and feral and free-roaming cats. Birds simply don’t perceive glass as a barrier. They see reflections of sky and trees as habitat and fly into a mirage.
Researchers estimate that up to 1 billion birds die every year in the United States from hitting windows. That’s a staggering number with huge population implications, because collisions are also indiscriminant—they kill healthy, fit birds as readily as weak ones—which culls birds from the population that would otherwise go on to breed successfully.
A 2014 study of 93,000 collision records across the U.S. showed that 44 percent of collisions occur at one- to three-story residential homes, 56 percent at low-rise buildings (under 11 stories), and less than 1 percent at high rises. This data reflects the sheer number of residential homes and low-rise buildings across the nation (123 million and 15 million, respectively), as compared to 21,000 high rises. Which means that we need to be addressing hazards for birds at all scales of development, not just at skyscrapers.
A feather-friendly dot pattern retrofit on reflective windows at Clean Water Services in Hillsboro helps minimize strikes.
Thankfully, there are cost-effective, even cost-neutral, design solutions that can synergistically meet a variety of design objectives. Our planning and design processes should be guided by big-picture ecological and sustainability objectives, and the question, ”How do we do this right so that we maintain the health of this region?
A growing number of local and national programs and projects have taken up the challenge of window collision reduction. The U.S. Green Building Council has added a Bird Collision Deterrence pilot credit to the LEED building credit library, an important step forward in recognizing this issue as a fundamental measure of the merit of a green building. FXFOWLE Architects used dot-patterned glass for the renovation of the Javits Convention Center in Manhattan, which has helped cut the building’s energy consumption by 26 percent, and has reduced the bird collision rate by a staggering 90 percent.
In the last 2 years, the Oregon Zoo has opened two new bird-safe buildings: Forest Hall (with UV-patterned glass) and the new Zoo Education Center (with acid-etched glass), the cost of which represented less than 1 percent of the total project budgets for each. The Port of Vancouver has shown great leadership in retrofitting their buildings with CollidEscape window film—a product that meets a triple bottom line: it reduces glare, reduces building cooling costs, and reduces confusing reflections for birds. The Port is also consulting with Portland Audubon on bird-safe recommendations for the master plan for its new waterfront development. Retrofits to address strike hazards have been installed at Clean Water Services in Hillsboro and at Lewis & Clark Law School in Portland.
Orange-crowned warbler felled by a deceptive courtyard reflection in Portland's South Waterfront neighborhood
This past November, Portland Audubon and partners developed a bird-safe demonstration project along OMSI’s Eastbank Esplanade, with three examples of do-it-yourself window retrofit solutions to minimize bird strikes on home windows. We have also been working with the City of Portland Bureau of Planning and Sustainability on integration of bird-safe glazing standards into the draft Central City 2035 plan.
However, despite all this progress, the number of individual projects and jurisdictions that integrate bird-safe considerations still represent just a tiny fraction of the overall development trend. We need to see much broader commitment to this work if we are going to make meaningful progress on addressing this source of mortality.
Light trespass and light pollution
Light pollution is a related hazard. Bird migration is a truly astonishing feat; millions of birds migrate every spring and fall, some of them traveling thousands of miles between their wintering grounds and their breeding grounds. Some of these migrants weigh just a fraction of an ounce. And most of them migrate at night, using constellations, the moon, and the magnetic pull of the earth to find their way. As they pass over brightly lit cities, skyglow confuses and lures them into the maze of urban areas.
In addition to hosting migratory birds on their way north or south, the night is actual habitat. Biological systems evolved on this planet in cycles of light and dark. When we light the night, we are in fact fragmenting habitat occupied by nocturnal species. We are also tampering with highly complex ecosystems that rely on carefully timed circadian rhythms that govern sleep, mating, migration, flowering, hunting, hibernation, bud burst, leaf drop, and the list goes on.
A bird-safe window retrofit demonstration at OMSI along Portland's Eastbank Esplanade
Artificial light repels some species and attracts others, causes some to chirp at night and others to remain silent, with dire repercussions for foraging, communication and reproduction. It is impossible to grasp the full extent to which light pollution disrupts incredibly complex and carefully choreographed relationships, with a cascade of consequences. LightsOut programs—in Portland and across the nation—help to mitigate such impacts.
A compounding issue is presented by the LED conversion that is sweeping the globe—the consequences of which we are only just beginning to investigate. A number of cities in our metro region have already made streetlight conversions from high-pressure sodium to light-emitting diodes (LEDs). LEDs offer significant energy savings and reduced maintenance costs, and there is an ever-increasing array of lamp options. However, too often the selected LED product is a ”cool” lamp that emits blue-rich white light, which scatters more readily in the atmosphere than longer wavelength light, thus increasing light trespass and skyglow.
This blue-rich white light impacts circadian rhythms in humans, plants, and fish and wildlife, as well as creating significant glare and suppressing melatonin production, which interferes with sleep cycles and may be linked to serious human health problems. The American Medical Association released a report in June of 2016 citing concerns about the human health impacts of blue-rich white light, and issued a statement encouraging municipalities to select warmer color temperature lamps.
The range of product options available today means that it is possible to achieve all the energy efficiency benefits of LED without compromising ecosystem or human health, and that’s the bar we should be setting for our region. Period.
Custom window film on the entrance to Hatfield Marine Science Center in Newport, Oregon, creates branding and visual interest while marking the otherwise highly reflective windows for birds.
Stray light, light trespass and skyglow from poorly designed lighting is increasingly being understood as a pollutant. Responsible lighting design factors into the livability of this region, providing important sustainability benefits including energy savings, cost savings, preservation of ecological and human health, reduction of our carbon footprint, and preservation of our view of the stars.
It is easy to minimize light trespass with well-designed lighting, and still provide all the light that we need. Audubon Society of Portland is working throughout the region to ensure that we are designing our built landscape for ecological resilience into the future. As we increase tree canopy targets, install eco-roofs, plant natives, and otherwise improve permeability for birds and wildlife in our urban environment, we need to prioritize ecosystem health, including mitigating hazards for birds, from window glass to lighting design.
Framework on the south, east and west aspects of the renovated Edith Green Wendell Wyatt Federal Building in downtown Portland was designed to reduce solar heat gain and cooling costs in the building, and also helps to interrupt confusing reflections in glass.
For more information, visit: http://audubonportland.org/issues/hazards/buildings/lo or contact Mary Coolidge, BirdSafe Campaign Coordinator, at mcoolidge@audubonportland.org.
To address window collisions at the residential scale, visit: http://audubonportland.org/issues/hazards/buildings/tips.
For architects and design professionals working at any scale, visit: http://audubonportland.org/issues/hazards/buildings/bird-friendly-building-design-toolkit