| NOCTURNAL COLLISIONS "Faith is the bird that sees the light while the dawn is still dark." Unknown Author |
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![]() Jay Smooth of www.hiphopmusic.com The white streaks you see in this image are in fact birds trapped in the "Tribute in Light" spots at the Ground Zero Memorial on September 11, 2004. |
Bird mortality at human-built structures
receives relatively little public attention,
but structural hazards are actually responsible
for more bird kills than higher profile catastrophes
such as oil spills. Human-built structures have been recognized as a hazard to birds for more than a century. However, the accelerated rate of urban development in recent years has seen the proliferation of radio and televi-sion towers, office buildings, power lines, cooling towers, emission stacks, and residential housing, all of which represent an increasing threat to flying birds In the dark, and especially in foggy or rainy weather, the combination of glass and light becomes deadly. Confused by artificial lights, blinded by weather, and unable to see glass, birds by the hundreds and even thousands can be injured or killed in one night at one building. Over 140 different species of birds have collided with buildings in Toronto alone. One expert estimates that across North America, up to 100 million birds die in collisions each year. Many species that collide frequently are known to be in long-term decline and some are already designated officially as threatened. Compared to habitat loss, pollution, and over-hunting, the issue of building collisions is neither well-known nor adequately understood. Yet across North America, more birds die from collisions each year than succumbed to the Exxon Valdez oil spill. |
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| Birds migrating at night are strongly attracted
to, or at least trapped by, sources of artificial
light, particularly during periods of inclement
weather. Approaching the lights of lighthouses,
floodlit obstacles, ceilometers (light beams
generally used at airports to determine the
altitude of cloud cover), communication towers,
or lighted tall buildings, they become vulnerable
to collisions with the structures themselves.
If collision is avoided, birds are still
at risk of death or injury. Once inside a beam of light, birds are reluctant to fly out of the lighted area into the dark, and often continue to flap around in the beam of light until they drop to the ground with exhaustion. A secondary threat resulting from their aggregation at lighted structures is their increased vulnerability to predation. The difficulty of finding food once trapped in an urban environment may present an additional threat. HOME |
![]() Toronto's Festival of Lights |
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