Study measures light’s radical impact on bird behaviour

Migratory birds are both attracted to and influenced by light. As a result, their behaviours alter drastically in the presence of artificial light at night, according to a new Oxford University collaboration, that was conducted at a unique landmark: the 'Tribute in Light' in New York. Every year, billions of birds undertake migratory journeys during the spring and autumn months. Most of these spectacular movements go unseen, occurring under the cover of darkness. However, a new study published in the Proceedings of the National Academy of Sciences offers compelling evidence that artificial light at night causes radical changes in the behaviours of migrating birds. Over the course of seven years, scientists from the University of Oxford, the Cornell Lab of Ornithology and New York City Audubon studied migrant bird behaviour in a truly unique setting: the "Tribute in Light" art installation that commemorates the September 11, 2001 terrorist attacks. In honour of the anniversary of the tragedy, in which nearly 3,000 people were killed, two blue beams of light, formed from 44 xenon bulbs of 7,000-watt intensity, shine into the night sky, mirroring the twin towers of the World Trade Center.