City noise causes robins to sing at night

University of Sheffield researchers have determined that British robins around the UK city have recently started singing at night because the urban noise drowns out their mating calls in the day. Apparently, the background noise in locations where the robins sing at night is on average ten decibel louder than elsewhere. From New Scientist:

There are two ways of looking at these results," says (scientist Richard) Fuller, who admits he does not know if the birds that sing at night are vocal in the daytime too. "On one hand, you could conclude that these birds are highly adaptable to the urban environment. On the other, it could be that they are suffering from the poor-quality habitat and having trouble attracting a mate."

If this is the case, says Fuller, the night-time singers could be sacrificing other activities such as feeding and preening in order to maximise their singing time.

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