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Scientists found that male great tits are singing at higher frequencies in order to combat the din of modern life.
But although their higher-pitched songs are being heard by females of the species, they are seen as less attractive.
Therefore males that struggle to make their low-frequency songs heard, or that change to less attractive higher tunes, are at risk of not finding a breeding mate.
Wouter Halfwerk from Leiden University in the Netherlands said: “These data are critical for our understanding of the impact of anthropogenic noise on wild-ranging birds, because they provide evidence for low-frequency songs being linked to reproductive success and to be affected by noise-dependent signal efficiency.”
His paper, published in the PNAS journal, is the latest to show the harmful effects of urban noise on songbirds.
Previous studies have suggested that some robins have abandoned the dawn chorus in order to sing at night, when the streets are quieter, while house finches in Mexico have taken to singing more loudly.
In the new experiment, great tits nesting in a Dutch national park were studied during April and May 2009 and 2010.
Researchers recorded the communication between males and females, analysed the paternity of chicks and played the female birds recordings of male songs with different levels of background noise.
They found that birds that sang low-frequency songs were less likely to be cuckolded by their mates, who in some cases “sneak away before sunrise” for “extra-pair copulations”.
When it was noisy, female birds were less likely to emerge from their nest boxes to mate when the males sang low-frequency songs at dawn, so “it pays urban birds to increase song frequencies when confronted with noisy conditions”.
In addition, “individuals that have to settle for noisy locations may suffer from reduced pairing and thus, reduced reproductive success”.