Female Cerulean Warblers recently were documented singing at and near their nests in Indiana (photo by Ryan O’Donnell).

More and more scientists are turning their attention to female birds, uncovering new behaviors and changing the way we think about female songs and calls. Karan Odom, a Cornell Lab of Ornithology researcher and her team used recordings in the Macaulay Library to discover that female bird songs have been documented in 64 percent of songbird species in the world. You and other birders may be able to help learn more about female bird songs too.

Prior to this discovery, most people, especially in the Northern Hemi­sphere, tended to think of bird song as a behavior exclusive to males, because in the Northern Hemisphere many male birds are conspicuous and vociferous. But around the world, females from more than 600 songbird species sing too.

Recently, researchers in Indiana added a new species to the list of birds in which females sing – Cerulean Warblers. Garrett MacDonald and colleagues from Ball State University documented two Cerulean Warbler females singing.

One female sang longer and more complex variations of the typical “zeet” call from her nest during the incubation period, often after the male sang. This female only sang when she had eggs in the nest and stopped singing when the eggs hatched. Another female sang a series of “zeets” only during the nestling stage while foraging near the nest.

MacDonald and colleagues suggest that the female songs they documented likely helps females maintain the bond with their mate. But females may sing for other reasons too and MacDonald and Odom urge birders and ornithologists to listen and try to document more female songbirds singing.

You can help researchers learn more about female bird songs too. This field of study is really still in its infancy, so if you are interested, please check out the Female Bird Song Project at http://femalebirdsong.org/ and add your field recordings to your eBird checklist. To refer to the original article that includes sonograms and recordings of the Cerulean Warbler songs, visit https://www.macaulaylibrary.org/2019/07/17/female-bird-song/

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