A rare bird hybrid has been identified in a San Antonio backyard, marking what scientists believe is the first documented vertebrate hybrid caused by climate-driven range shifts.
In June 2025, a local resident spotted a bird with the blue plumage of a blue jay, but it had black spots over its eyes, a characteristic of green jays.
“This is the first record of non-captive hybridization between a Green Jay and a Blue Jay”
“This is the first record of non-captive hybridization between a Green Jay and a Blue Jay,” wrote Brian Stokes, a University of Texas at Austin graduate student, in the Ecology and Evolution journal. Stokes employed nets to capture the bird for documentation and genetic testing, confirming it was a hybrid.
Historically, blue jays and green jays occupied separate regions: blue jays in the eastern U.S., green jays in Central America. But over recent decades, climate change has altered their ranges, pushing green jays northward and blue jays westward into Texas. This overlap created conditions for hybridization.
Scientists are now closely watching such developments, as shifting ranges due to warming temperatures may increase hybridization events among other species, underscoring the effects of climate change on wildlife distribution and genetics.
