Researchers report that egg-laying dates among two populations of tree swallows near Ithaca, New York, advanced by approximately 13 days between 1972 and 2015 as daily temperatures during the breeding season increased; earlier laying has nearly doubled the risk of nestlings experiencing cold snaps associated with reduced aerial insect availability and mass chick mortality, highlighting the complex ways in which climate change can affect animal life cycles and survival, according to the authors.
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Article #20-09864: "Birds advancing lay dates with warming springs face greater risk of chick mortality," by J. Ryan Shipley et al.
MEDIA CONTACT: J. Ryan Shipley, Max Planck Institute for Animal Behavior, Radolfzell am Bodensee, GERMANY; tel: +49-1520-386-4693; e-mail: < rshipley@ab.mpg.de >
Proceedings of the National Academy of Sciences