Birds of a New Feather

There is a blue jay, and there is a green jay. The former (Cyanocitta cristata) is a temperate bird found across the Eastern US, the latter (Cyanocorax luxuosus) is a tropical bird found across Central America. The two are separated by 7 million years of evolution, and they have stayed out of each other’s way for most of that time.  

Recently, however, researchers say they are meeting and mating, resulting in one of the first examples of a hybrid creature that is the result of recent changes in climate patterns. 

“We think it’s the first observed vertebrate that’s hybridized as a result of two species both expanding their ranges due, at least in part, to climate change,” first study author Brian Stokes said in a statement, adding that previous vertebrate hybrids were the result of human activity. 

In the 1950s, green jays barely reached southern Texas, while blue jays extended only as far west as Houston, so the two rarely met. Since then, however, green jays have moved north and blue jays west, making their ranges converge around San Antonio.  

Stokes first spotted the hybrid bird on a social media post by a woman in a suburb northeast of San Antonio. In the picture, he saw an odd-looking blue bird with a black mask and white chest that looked vaguely like a blue jay, but that was also clearly different. Stokes then went to observe for himself. 

“The first day, we tried to catch it, but it was really uncooperative,” he said. “But the second day, we got lucky.” 

After doing so, he took a blood sample of the bird, banded its leg for future identification, and then released it.  

According to an analysis, the bird is a male hybrid born to a green jay mother and a blue jay father. It is similar to a hybrid that scientists produced in captivity in the 1970s by crossing the two species. 

“Hybridization is probably way more common in the natural world than researchers know about because there’s just so much inability to report these things happening,” Stokes said. “And it’s probably possible in a lot of species that we just don’t see because they’re physically separated from one another and so they don’t get the chance to try to mate.”