This App Identifies Birds by Their Songs
The Cornell Lab of Ornithology recently added the ability to identify birds from hearing their birdsong to their Merlin Bird ID app — a “Shazam for bird songs” as Fast Company says. You just start recording with your phone and the app starts telling you the birds it’s hearing. Here’s how it works:
Automatic song ID has been a dream for decades, but analyzing sound has always been extremely difficult. The breakthrough came when researchers, including Merlin lead researcher Grant Van Horn, began treating the sounds as images and applying new and powerful image classification algorithms like the ones that power Merlin’s Photo ID feature.
“Each sound recording a user makes gets converted from a waveform to a spectrogram-a way to visualize the amplitude [volume], frequency [pitch], and duration of the sound,” Van Horn says. “So just like Merlin can identify a picture of a bird, it can now use this picture of a bird’s sound to make an ID,” Van Horn says.
This pioneering sound-identification technology is integrated into the existing Merlin Bird ID app, meaning Merlin now offers four ways to identify a bird: by a sound, by a photo, by answering five questions about a bird you saw, or by exploring a list of the birds expected where you are.
Margaret Renkl tried the app out and it seems to work pretty well:
I set my phone down on the table on my back deck, opened the Merlin app, chose “Sound ID” and hit the microphone button. Immediately a spectrogram of sound waves began to scroll across the screen. Every time a bird sings, the sound registers as a kind of picture of the song. By comparing that picture with others in its database, the app arrives at an ID.
I watched as Merlin rolled out the names of bird after bird — tufted titmouse, European starling, Carolina chickadee, northern cardinal, American crow, white-breasted nuthatch, eastern towhee, house wren, American goldfinch, blue jay, eastern bluebird, American robin, Carolina wren, house finch. It didn’t miss a single one.
What amazed me was not merely the accuracy of the ID but also the way the app untangled the layers of song, correctly identifying the birds that were singing in my yard, as well the birds that were singing next door and the birds that were singing across the street. If the same bird sang a second time, the app highlighted the name it had already listed. Watching those highlights play across the growing list of birds was almost like watching fingers fly across a piano keyboard.
See also this video review. You can download the app here. I’m going to give this a shot over my lunch hour today. I try to eat outside when the weather is nice and there are always birds out singing.