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USD biology professor says winter in South Dakota is for the birds

VERMILLION, S.D. -- David Swanson, Ph.D., University of South Dakota professor of biology and contributing author of “Birds of South Dakota,” has spent more than 25 years studying birds. He recently has been publicized for his knowledge and work with bird adaptation to climate change in Audubon, a conservation magazine based in New York.

Birds go through physical, physiological and behavioral changes to prepare for the cold winters. Swanson is especially interested in these physiological changes.

“One major contribution to the birds’ physiological adjustments during the winter is their bigger muscles, which we’ve been noticing more over the last few years,” Swanson said.

While many larger birds are able to add more insulation from feathers, the smaller birds use their muscles to shiver explains Swanson. This produces heat for them.

According to Swanson, the birds that are in South Dakota year round include the Black-capped Chickadee, White-breasted Nuthatch, House Sparrow, American Goldfinch, House Finch and the Northern Cardinal. Certain birds, including the Dark-eyed Junco and the American Tree Sparrow, fly from Canada to nest in South Dakota for the winter.

These birds are true of the eastern side of South Dakota. The western side of the state closely compares to all the northern states west of the Dakotas, though Swanson notes that Dark-eyed Juncos do live in the Black Hills year round, even though they are natives of Canada. It is because of the forests in that region that attract them, said Swanson.

Swanson also notes that although an extremely harsh or extremely mild winter does not really throw these birds off, the biggest problem is when there is a vast change in a short period of time. The preparation the birds go through before a winter takes at least a week.

Swanson teaches several biology courses at USD, including Ornithology, which is the study of birds. He is currently the secretary of the South Dakota Ornithologist’s Union. A photo of Swanson is available for download at


Founded in 1862 and the first university in the Dakotas, the University of South Dakota is the only public liberal arts university in the state, with 202 undergraduate and 78 graduate programs in the College of Arts & Sciences, School of Education, Knudson School of Law, Sanford School of Medicine, School of Health Sciences, Beacom School of Business and College of Fine Arts. With an enrollment of nearly 10,000 students and more than 400 faculty, USD has a 16:1 student/faculty ratio, and it ranks among the best in academics and affordability. USD’s 18 athletic programs compete at the NCAA Division I level.

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Hanna DeLange
USD News