Several times over the last few weeks we have been away over the weekends for a day or two. Awakening in a new place, we almost always step outside to hear what birds are singing in the area. On our recent trips we have enjoyed listening to “trillers”—birds that sing a song consisting of a rapidly repeated series of notes on the same pitch. Many people find it challenging to differentiate among the different species that share trilling-type songs; even experts can be stumped by some individuals whose songs can shade into sounding like what we think of as the typical song of another species.

The triller most commonly heard is the chipping sparrow. These little red-capped sparrows occur around most suburban neighborhoods as long as there is a bit of lawn on which to feed and some bushes to place a nest. The males sing a typically long, rather fast trill that is often described as sounding somewhat dry sounding—we often think of their song as sounding a bit like a person’s long, raspy inward breath. The chipping sparrow song is so ubiquitous in summer in much of North America that it quickly becomes background noise even to birdwatchers. Probably many people think that it is the sound of an insect—maybe a cicada, which also has a buzzy trill, though faster and more whiney.

A trilling song that floats down from a white pine tree is more likely coming from the aptly named pine warbler. Its song is typically more liquid-sounding, meaning, it is a bit slower and the individual notes are less separated and less percussive than in the chipping sparrow. Given the fact that Maine is the pine tree state, it is not surprising that pine warblers are quite common here, but they are remarkably tied to pine trees during the breeding season.

The songs of dark-eyed juncos are perhaps the most similar to chipping sparrows in our area, especially because chipping sparrows can show great variation in their songs among individuals. Junco songs typically sound higher and more musical than chipping sparrows and juncos are more likely to be found in and around openings in forest with lots of coniferous trees. Around the Maine coast including the Boothbay peninsula area, there are places where homes and lawns are set in a forested landscape with coniferous trees—a mix of habitats where chipping sparrows and dark-eyed juncos could occur together. For a birder trying to learn the songs of the trillers, this could a blessing or a curse! We suggest treating it as an opportunity to study the subtle differences in their songs.

Once you start listening closely to these trilling songs you will also note how much variety there can be not only among individuals but even how many different versions of the song an individual bird can sing. Just like we can pick out the sound of the voices of our loved ones in a crowd, these birds can tell who is who from the songs they sing.

Jeffrey V. Wells, Ph.D., is a Fellow of the Cornell Lab of Ornithology. Dr. Wells is one of the nation's leading bird experts and conservation biologists and author of the “Birder’s Conservation Handbook.” His grandfather, the late John Chase, was a columnist for the Boothbay Register for many years. Allison Childs Wells, formerly of the Cornell Lab of Ornithology, is a senior director at the Natural Resources Council of Maine, a nonprofit membership organization working statewide to protect the nature of Maine. Both are widely published natural history writers and are the authors of the book, “Maine’s Favorite Birds.”