LONDON, March 25 (Reuters) - The early bird is getting even earlier.
With climate change spurring earlier springs across much of North America, many birds are laying their eggs earlier in the year, according to a new study – adding to mounting evidence that global warming is turning wildlife habits upside down.
Of 72 bird species examined around Chicago, roughly a third lay their eggs about 25 days earlier than they did a century ago, researchers report in the paper published on Friday in the Journal of Animal Ecology.
Those affected include the mourning dove, American kestrel and Cooper's hawk.
The scientists so far haven't found any clear traits shared by these species, such as size or migratory status, that might explain why they’re changing their schedules.
But "the majority of the birds we looked at eat insects, and insects' seasonal behavior is also affected by climate," said lead author John Bates, curator of the bird division at the Field Museum in Chicago.