A study suggests that migratory behavior and winter geography may affect birds' ability to adapt to climate change. Populations of North American migratory bird species have declined by nearly 2.5 billion individuals in the past half-century, even as resident species populations have remained stable. Clark Rushing and colleagues analyzed 43 years of monitoring data from the North American Breeding Bird Survey using a dynamic species distribution model to quantify the rate of latitudinal breeding range shifts for 32 eastern North American bird species. For migratory species that winter in the Neotropics, the southern limits of their breeding ranges shifted northward over the study period, 1972-2014, whereas their northern range limits did not change significantly. For both resident and temperate-wintering migratory species, northern range limits shifted northward but southern range limits did not change. Consequently, the latitudinal distribution of Neotropical migrants contracted, whereas that of residents expanded. The results suggest that resident and temperate migratory species may be relatively resilient to future climate change owing to their ability to colonize newly suitable habitat and to adapt in place. On the other hand, Neotropical migratory species may be constrained in their ability to respond to climate change and thus may be particularly vulnerable to future climate change, according to the authors.
Article #20-00299: "Migratory behavior and winter geography drive differential range shifts of eastern birds in response to recent climate change," by Clark S. Rushing, J. Andrew Royle, David J. Ziolkowski Jr., and Keith L. Pardieck.
MEDIA CONTACT: Clark Sawyer Rushing, Utah State University, Logan, UT; tel: 404-295-9391; e-mail: crushing05@gmail.com
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Proceedings of the National Academy of Sciences