27 October 2017
By Andy Coghlan
For the first time, female
dark-eyed juncos have been found to burst into song in the wild. Although many
female tropical birds sing, singing females are rare among northern,
temperate songbirds. However, the behaviour is now becoming more
common, and climate change may mean it becomes even more widespread.
Dustin
Reichard of Ohio Wesleyan University knew that female dark-eyed
juncos (Junco hyemalis)
sometimes sang in captivity, but only after being injected with testosterone.
To find out if they sang in the wild, he and his colleagues goaded them by
placing a live, caged female in their territories. The researchers also played
recordings of a soft trill that females make when they are receptive to mating.
In all, 17 females, along with 25
males, interacted with the caged females. Half the females dived and lunged at
them, and a minority also performed aggressive tail-spreads not normally seen
in females. Three of the females sang songs similar to those of males.
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