US skyscrapers kill millions of birds a year, reports find

Studies have found that the bright lights and glazing of towering structures in US cities including New York, Chicago and Los Angeles are causing millions of migratory birds to die each year.
A study published by Cornell Lab of Ornithology this week ranked 125 US cities based on the danger they pose to birds. It found that Chicago is one of the most popular migration paths for birds in the US, and therefore the most dangerous.
The dense metropolitan areas of New York City and Los Angel