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Skyscrapers are killing millions of birds

This month brings with it the shocking news that skyscrapers in the US are killing at least 100 million birds every year. Scientists have been taking a closer look at the issue and believe that as many as one billion birds could perish each year following collisions with buildings. Following a huge study, conservationists now have a much better idea which cites are the most deadly for birds.

The trouble with Chicago

The research has revealed that Chicago is the deadliest city for avian species. The Chicago skyline features many glass tower blocks and this area of the country sees the most migrating birds in the sky. It’s a bad cocktail! Migrating birds journey twice a year, going north in the spring from Central and South America, across the Great Lakes to Canada, and then returning south in the autumn.

New York, New York

The famous Manhattan skyline is another death trap for birds and migrating species in particular. Birds land in the city to rest at night and when daylight arrives, they see what they think is a tree and fly towards it but that tree is often merely a reflection in the glass of a building. The birds smash into the glass and are killed.

Many migrating birds fly at night when the air is cooler and are often attracted towards cities with their bright lights. Any city with glass buildings and bright lights at night is a problem, but some are more dangerous to birds than others. Experts believe that it is actually low-rise and medium-rise structures which cause the most accidents, but the enormous skyscrapers are also an issue.

The most dangerous cities

Following extensive research, the Cornell Lab of Ornithology recently published a study that ranks cities based on the danger they pose to the birds. Chicago was the most dangerous with Houston and Dallas completing a trio of shame! Houston and Texas, like Chicago, lie on major migration paths. Next on the list of offenders were New York, Los Angeles and Atlanta.

Raising awareness of collisions

The scientists are attempting to raise awareness of the problem and hope that their findings will help to reveal solutions. It is important that the number of collisions is mitigated and the have estimated that the number of deaths could be as many as one billion.

Certain species of birds are more susceptible to collisions than others. Another study conducted by the University of Michigan found that songbirds, such as and , are more likely to collide with buildings. This is because they chirp when they see the bright lights of a city and so attract other birds to the danger zone.

Finding solutions

There are measures that can be taken to reduce collisions. Turning out the lights in buildings at night for a few weeks during peak migration periods could make a big difference. New York and Minnesota have already participated in conservation schemes and have turned off the lights in state-operated buildings at night during migration. Conservationists have also suggested that buildings use patterned glass and dimmer lighting.

One billion birds are far too many to lose. Cities pose a huge threat to birds and this is an issue which is only going to get worse unless birds are a serious consideration during the design process of new structures.


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