Date: November 2, 2015
Source: University of Illinois at Urbana-Champaign
A new study explores how a young cowbird, left as an egg in the nest of a different species, grows up to know it's a cowbird and not a warbler, thrush or sparrow.
The study, published in Animal Behaviour, reveals that cowbird juveniles leave the host parents at dusk and spend their nights in nearby fields, returning just after daybreak. This behavior likely plays a role in the cowbirds' ability to avoid imprinting on their host parents.
"If I took a chickadee and I put it in a titmouse nest, the chickadee would start learning the song of the titmouse and it would actually learn the titmouse behaviors," said Matthew Louder, who conducted the study as a Ph.D. student with Illinois Natural History Survey avian ecologist Jeff Hoover and INHS biological surveys coordinator Wendy Schelsky. "And then, when it was old enough, the chickadee would prefer to mate with the titmouse, which would be an evolutionary dead end," he said.
Louder is now a postdoctoral researcher with East Carolina University in North Carolina and Hunter College in New York.