https://phys.org/news/2018-11-discovery-rare-three-species-hybrid-warbler.html

A dedicated bird watcher and contributor to eBird.org in Roaring Spring, Pennsylvania, first noted the oddity in May 2018. Lowell Burket says he spends time birding and relaxing in the woods on family-owned property where he also likes to take photos and video of birds. In one piece of video he noticed a male bird that sang like a Chestnut-sided Warbler but had some of the physical characteristics of both Blue-winged and Golden-winged Warblers. Burket saw the bird again a number of times, reported it to eBird, and got in touch with researchers in the Cornell Lab's Fuller Evolutionary Biology Lab.

"I tried to make the email sound somewhat intellectual so they wouldn't think I was a crackpot," Burket recalls. "Having the photos and video helped. Within a week researcher David Toews came down. We found the bird again and collected a blood sample and measurements. It was a very interesting and exciting morning for us. A few days later I got a text message from Dave saying, 'You were right!!!'"