This audio story is brought to you by BirdNote, a partner of The National Audubon Society. BirdNote episodes air daily on public radio stations nationwide.
The tiny Common Redpoll, one of the smallest members of the finch family, weighs only as much as four pennies, yet it survives the cold and darkness of winter in the far North. Most birds depart in autumn to warmer climes. But redpolls feed on birch and alder seeds that are available throughout the winter, no matter how deep the snow. They do it in the cleverest of ways through a series of precise adaptations.
Redpolls are acrobats, feeding with ease on the smallest of branches, even hanging upside down to extract seeds from birch catkins. They may shake a catkin vigorously, then drop to the snow to pick up the fallen seeds in a more sheltered spot. This little bird typically eats 40% of its body weight in seeds every day to keep itself alive.
The redpoll’s expanded esophagus allows it to store large numbers of seeds during rapid feeding. The bird then retires to a dense conifer and while sheltered from the freezing winds, brings up the seeds one by one, cracking their shells and swallowing the nutritious kernels. In a land of extreme winter conditions, redpolls are survivors.
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