Overview

• The peer‑reviewed study in Ecology and Evolution reports roughly equal nuclear DNA from both species, with mitochondrial DNA indicating a green jay mother.
• Researchers trapped the bird in 2023 using a mist net, collected a blood sample, banded it, released it, and documented its return to the same yard in June 2025.
• Scientists link the event to concurrent range expansions influenced by warming temperatures and land‑use changes that brought the two species into contact.
• Only one hybrid individual is known so far, it is not a new species, and birders have nicknamed it the “grue jay” as researchers solicit additional sightings and recordings.
• A similar cross was produced in captivity in the 1970s, and the authors say this may be the first observed vertebrate hybrid resulting from both parent species expanding their ranges in part due to climate change.