Birds native to Europe are on average less colorful now than observed 15 years ago, according to a new study that suggests the climate crisis could be behind the change.
Researchers, including those from the University of the Basque Country in Spain, assessed two populations of blue tits in southern France, one located on the outskirts of Montpellier and the other in the island of Corsica over a 15-year period from 2005 to 2019, The Guardian reported.
They gathered over 5,800 observations on several characteristics of the blue tits, including its striking coloring – the bird has a blue crest and a yellow breast.
The results, published recently in the journal The American Naturalist, showed a decrease in both populations of blue and yellow coloration between 2005 and 2019, meaning the blue crests and yellow breasts are on average less colorful right now than when research began.
“Our work suggests that environmental changes, and specifically climate change, could be the main reason why birds such as the blue tit are undergoing a change in their physical features, more specifically in the brightness and intensity of their coloration,” said David Lopez-Idiaquez, a co-author of the study.
“A negative trend in terms of brightness and intensity of plumage coloration in both sexes and populations has been observed, although in Corsica this change is more associated with climate,” he explained.