Transient Wintering Bird Detection Requires Different Methods

[Cara J]

Birds of a feather don’t always flock together. During the winter, some birds of the same species like to create and defend a territory while other birds like to constantly be on the move, searching for the best resources. This makes it difficult for researchers to conduct surveys for birds like American redstarts (Setophaga ruticilla) that winter in Jamaica. Compounded with transience of some of the birds, American redstarts present chip notes — short, high-pitched calls — rather than songs, making detecting and studying them even more challenging. In a new study published in The Auk: Ornithological Advances, researchers found that common survey methods for the birds don’t accurately portray the whole population because they don’t account for transient birds. “We realized there was a disparity between population estimates in unmarked surveys or point counts versus territory-mapping methods, which include catching, banding and mapping birds’ movements,” said Ashley Peele, coordinator for the Virginia Breeding Bird Atlas based at Virginia Tech University and lead author of the recent study. “Basically, the disparity after looking closely at the data was that quite a few transient individuals were overlooked by traditional mapping methods.” To conduct their research, Peele and her colleagues spent four years [...]

 

Read more: http://wildlife.org/transient-wintering-bird-detection-requires-different-methods/