Study Finds City Birds Sing In Higher Key
December 14, 2011 by UPI - United Press International, Inc.
ABERYSTWYTH, Wales, Dec. 13 (UPI) — City birds sing their songs at a higher pitch than their country cousins to reduce the affect of echoes from surrounding buildings, a British study determined.
Researchers from Aberystwyth University said they found higher-pitched songs travel further in built-up areas because their echoes fade more quickly, and following notes are clearer and easier to pick out.
“Our cities are packed with reflective surfaces, open spaces and narrow channels, which you just don’t get in woodland,” researcher Emily Mockford told The Daily Telegraph.
“Because sounds bounce and travel in different ways, birds have to use songs that can cope with this.”
It had previously been suggested birds raised their pitch in urban areas to distinguish their song from the low-pitch drone of traffic and machinery.
Birds may also use song to determine their distance from one another, experts said.
“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,” researcher Rupert Marshal said.
“In cities there are fewer visual obstacles and song doesn’t degrade as quickly, so city birds may just concentrate on being heard.”