Birds sing in a higher pitch to travel further in urban areas
Last updated 1/30/2012 2:51:21 PM
Birds sing in a higher pitch to travel further in urban areas
Birds have changed the pitch of their birdsong to a higher pitch to help them travel further in built-up areas, according to new research.
Scientists from Aberystwyth University and the University of Copenhagen have found that it is the buildings that are changing the way that birds sing in cities.
Their new study suggests that urban architecture may be just as important as background noise in shaping how our birds sing.
"Our cities are packed with reflective surfaces, open spaces and narrow channels, which you just don't get in woodland," says researcher Emily Mockford. "Because sounds bounce and travel in different ways, birds have to use songs that can cope with this. The higher notes mean the echoes disappear faster and the next note is clearer."
Dr Rupert Marshall, Lecturer in Animal Behaviour, added: "In woodland where trees and leaves obscure the view, many species of songbird can tell how far away a rival is by how degraded its song is. In cities there are fewer visual obstacles and song doesn't degrade as quickly, so city birds may just concentrate on being heard."
Previously it was thought that great tits and other common birds sung at a higher pitch in noisy areas to avoid the low pitch noise from traffic and industry.