Read the full story from the Wildlife Society.
Climate change has likely caused migratory birds’ bodies to get smaller and their wings to get longer over the years, and the timing of their migrations has shifted substantially.
Researchers determined this by tapping into a one-of-a-kind dataset from the Field Museum in Chicago. Since the 1970s, museum staff and volunteers have collected migrating birds that crashed into Windy City buildings. One researcher—Field Museum ornithologist David Willard, now the collections manager emeritus—recorded body size and wing length of every single dead bird, where the crash occurred and when. Together, this effort resulted in nearly a half-century of data on more than 70,000 individuals of 52 migratory bird species.
That helped a team of biologists add to a growing body of research suggesting that climate change has affected the size and shape of a variety of species. In their latest study, published in the Journal of Animal Ecology, the team revisited those findings by looking at how changes in body size were related to changes in migration timing.