Glassy death traps

Bird Deaths
Last Updated 05 November 2012, 12:47 IST

The instances of birds hitting the glass towers of Toronto, Canada’s most populous city, are many. Every day, volunteers   scour the streets of the financial district for dead birds in the predawn darkness. Glass facades disorient birds as they reflect the surrounding trees, writes Ian Austen

In the shadow of the massive black towers of a bank’s downtown headquarters, here was an almost indistinguishable puff of dark gray fluff on the sidewalk. It was the body of a golden-crowned kinglet that had crashed into the iconic Toronto-Dominion Center building.

There is no precise ranking of the world’s most deadly cities for migratory birds, but Toronto is considered a top contender for the title. When a British crew wanted to film birds killed by crashes into glass, Daniel Klem Jr., an ornithologist at Muhlenberg College in Allentown, Pa., who has been studying the issue for about 40 years, directed them here, where huge numbers of birds streaking through the skies one moment can be plummeting toward the concrete the next.

So many birds hit the glass towers of Canada’s most populous city that volunteers scour the ground of the financial district for them in the predawn darkness. They carry paper bags and butterfly nets to rescue injured birds from the impending stampede of pedestrian feet or to pick up the bodies of dead ones.

The group behind the bird patrol, the Fatal Light Awareness Program (FLAP), estimates that one million to nine million birds die every year from collisions with buildings in the Toronto area. The group’s founder once single-handedly recovered about 500 dead birds in one morning. Toronto’s modern skyline began to rise in the 1960s, giving it a high proportion of modern, glass-clad structures, forming a long wall along the northwestern shore of Lake Ontario.

That barrier crosses several major migratory flight paths, the first large structures birds would encounter coming south from the northern wilderness. Though those factors make Toronto’s buildings particularly lethal, Klem was also quick to say that the city also leads North America when it comes to addressing the problem.

Recourse to law

After years of conducting rescue and recovery missions and prodding the city to include bird safety in its design code for new buildings, FLAP has recently begun using the courts to help keep birds alive. It is participating in two legal cases using laws normally meant to protect migratory birds from hunting and industrial hazards to prosecute the owners of two particularly problematic buildings. On a recent volunteer bird patrol, Michael Mesure, who founded FLAP 19 years ago, pointed out many examples of killer buildings. As he neared one particularly troublesome spot, on the eastern edge of the financial district, he pointed to a gaggle of sea gulls sitting in trees across the street from an office building.

They were waiting, he said, to dine on the smaller birds maimed or killed by the building. The building has a glass facade that disorients birds by reflecting the surrounding trees. Perceiving the reflection as habitat, birds zoom at it full throttle without regard for the danger. The victims are largely songbirds. Perhaps because of familiarity, the urbanites of the bird world, like house sparrows, pigeons and gulls, are much less prone to crashing into glass, Klem said.

All the birds collected by FLAP, dead or alive, go into paper bags. Though there were no survivors that recent morning, the merely stunned or frightened would have been released in a park near the shore of Lake Ontario. The injured would have been taken to one of two animal rehabilitation centres outside the city. The dead birds, with the location of their deaths marked on their bags, first end up in a freezer at FLAP’s headquarters. Although the autumn migration was barely under way, the freezer was already close to full. Its contents ranged from owls to hummingbirds, and the vividness of their plumage was generally offset by the gruesomeness of their smashed heads.

Simple solutions

One especially effective, if unpopular, method of reducing the threat to birds, Mesure said, is simply to cover the outside of windows up to the height of adjacent trees with the finely perforated plastic film often used to turn transit buses into rolling billboards. The film can be printed with advertising or decorative patterns, although the group has found that a repetitive pattern of small circles made from the same adhesive plastic is both effective and less likely to prompt aesthetic objections. For new buildings, the solution can be as simple as etching patterns into its glass.

A German glass company is also developing windows that it hopes can take advantage of the ability of birds to see ultraviolet light, by including warning patterns that are invisible to humans. But even after nearly two decades of drawing attention to the problem, Mesure acknowledged that the threat to birds is still rarely considered by architects and developers. The effect of legal proceedings against using glass is obvious at Consilium Place, a suburban complex of three office towers involved in the first prosecution. Consilium sits between a river valley that is a major migratory bird resting spot and Lake Ontario.

The location and the reflective glass exterior on two of the buildings, helpful in reducing heating and air-conditioning costs, but deceiving to birds, make it consistently among the city’s most dangerous structures for birds, Mesure said. The former owner consistently rejected proposed solutions on the basis of cost and aesthetics, he said. But since the complex was sold this year, the new owner has begun to apply a pattern of small white dots on the windows. While far from complete, the measure was already having an effect. A freezer for storing dead birds, which the new landlord had placed in an underground parking garage, contained only a dozen remains, far fewer than usual during a migratory period.

In the case of the Toronto-Dominion Center, however, the birds are also running up against aesthetic concerns. The soaring 1967 towers are the last major work of the modernist master Mies van der Rohe. The property’s owner said it recently applied a dot-pattern film on the windows to protect birds, but used a black pattern apparently to avoid detracting from the architect’s minimalist design. But because they blend in, Mesure said, the black dots are ineffective as a warning for birds.

The company declined an interview request, but in a statement said, “Bird protection is a matter we take seriously.” The activists’ final stop that morning made it clear that buildings do not have to be skyscrapers to be lethal. A dead chickadee and red-breasted nuthatch lay at the base of a small industrial building that featured mirrored blue glass that reflected an adjacent woodlot.

(Published 05 November 2012, 12:25 IST)

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