Mysterious Bird Is the First-Ever Documented Hybrid of Its Kind
Mom was a rose-breasted grosbeak and dad was a scarlet tanager.
The 1-year-old offspring of a rose-breasted grosbeak and scarlet tanager.
Here's a beautiful story for anyone who appreciates birds. A female rose-breasted grosbeak got together with a male scarlet tanager despite the bird species' preferences for dwelling in different habitats. Their offspring, a male, has now made ornithology history as the first-ever documented hybrid of its kind.
"I love this story, because it starts with a little mystery and ends with a surprising discovery," said biologist David Toews in a Penn State statement Wednesday. Toews is the lead author of a study in the journal Ecology and Evolution on the rare bird, which was discovered in mid-2020 by birder Stephen Gosser in the woods in Western Pennsylvania.
Male scarlet tanagers are lookers. They have bright red bodies and dark wings. Male rose-breasted grosbeaks are accurately named for the red splash on their chests, while the females have subtler colors. The birds' lineages diverged around 10 million years ago. The grosbeaks prefer the edges of woodlands, while the tanagers hang out up high in forest canopies.
Gosser heard a tanager's song, but traced it to a bird that looked more like a grosbeak. Gosser sent up the equivalent of a bat signal for birders and a team from the National Aviary in Pittsburgh came in, caught the young bird and got a blood sample.
A study of the mystery bird's DNA combined with an analysis of its song led the research team to an understanding of its remarkable hybrid roots. Birds usually learn their songs from their dads, so either the papa tanager stuck around or the bird learned its tune from another male tanager nearby.
The song part of the study involved more than enjoying the pretty sounds.
"Something people may not understand is that when we analyze birdsongs, we're not actually listening to them. We're looking at them," said Toews. "We're looking at wavelengths of the sound — or the 'spectrogram' is a more accurate term — and we're actually measuring visual components of a soundwave to analyze the song."
The bird's fate is unknown. The study noted "we could not verify reproduction by this individual hybrid, and a careful search for the bird on territory in 2021 was unsuccessful."
Another aspect of this tale that will remain a mystery is how the mom and dad met in the first place. The study also didn't address a possible nickname for the bird. Grosager? Tanabeak? Steve? Whatever you call it, it was a rare discovery.