In this season when many bird species are on the move to overwintering areas, activity seems to have increased among one of the tiniest but most common birds in the Blue Ridge, the least flycatcher (Empidonax minimus).
Like many species that prefer cooler climes for breeding, most eastern flycatchers spend the spring and summer far north of Virginia, well into Canada, but also extend their range throughout much of the cool elevations of the Appalachian Mountains — in this case, all the way down to South Carolina.
These little birds (4.7 to 5.5 inches) should soon be on their way to their wintering grounds at the southern tip of Florida or in Central America. Perhaps the increased activity indicates more least flycatchers have joined our summer population on their way south, or our summer population is just busier fattening up for the flight.
Busy is the operative word for least flycatchers, in the tyrant flycatcher family (Tyrannidae). They’ve been flitting everywhere in and around the forest edge near my house, animatedly calling “che-bec´” to each other. The call is so distinctive that this flycatcher is also commonly called “chebec,” according to “A Natural History of American Birds of Eastern and Central North America,” by Edward Howe Forbush and John Richard May.
Forbush and May’s large book, published in 1955, has charming illustrations by well-known nature illustrators Louis Agassiz Fuertes, Allan Brooks and Roger Tory Peterson. The text is also worth reading, with wonderful, if somewhat dated, descriptions of the natural history of bird species.
While using references this old to learn about nature has its pitfalls, because science continually marches on and even the classification and names of species can change, I enjoy reading them to see how scientists’ views have evolved, and just for the marvelous descriptions in so many of them. Here’s how Forbush and May describe the least flycatcher’s call and accompanying behavior:
“The loud unmusical chebéc is uttered with the utmost vim and vigor, accompanied by an upward jerk of the head and a flirt of the tail, as if to call attention to the little bird’s superior musical abilities, while some of his softer notes are given with a characteristic trembling of the wings, as if he were rendering ecstatic melodies.”
From my limited observations of this flycatcher, I’d go more with “harsh” than “loud” — and constant. They just never seem to shut up. Then again, the ones I’ve observed have been foraging in pairs, rarely more than 20 feet up in trees and bushes or more than a few feet from each other. Perhaps this constant chatter is a way of communicating where the food is or where to go next, as the pair flits through the trees.
With their constant movement, it took me a while to identify the species. Along with its call, I noted its size and bright-white eye ring, which is distinctive among flycatchers. While I can’t speak for much of the least flycatcher’s behavior beyond my brief observations of them, Forbush and May’s overall characterization of it seems apt:
“The least flycatcher or ‘Chebec’ may be characterized by superlatives. It is the smallest, earliest, tamest, smartest, bravest, noisiest and most prominent member of its genus in the East and many ladies will agree that it is the dearest.”
Okay, these books can be more than somewhat dated.
Unlike the other small flycatchers of its genus, the least flycatcher “has gradually become accustomed to man and his works and prefers his neighborhood to more retired localities,” Forbush and May write. For habitat, it prefers aspen groves, open woods, shade trees and orchards. Among its prey are many agricultural pests. This time of year, with insects getting scarcer as days get colder, berries serve to round out the least flycatcher’s diet.
Birds that hunt flying insects, such as tyrant flycatchers, use one or more of five basic techniques, as explained by H.A. Ford and others in their 1988 article, “The Relationship between Ecology and the Incidence of Cooperative Breeding in Australian Birds”: gleaning (foraging for insects on leaves, branches and trunks of trees); snatching (while in flight, grabbing prey from the ground or a branch); hawking (leaving a perch to take prey from the air); pouncing (dropping to the ground to take prey); and pursuing (taking insects from air).
There are variations on these hunting techniques. According to Cornell Lab of Ornithology’s AllAboutBirds.org, the least flycatcher hunts through hawking and “hover-gleaning,” which adds hovering in the air like a hummingbird to the gleaning process. My resident pair of eastern phoebes, also in the tyrant flycatcher family, often hover-glean for insects under the eaves of my house.
Among the many great features of the site is a “Cool Facts” list for each species. A lover of what I think of as fascinating factoids, this list is one of my favorite features of the site. Despite Forbush and May’s depiction of them, the least flycatcher is not exactly fascinating, but it does have two items in the “Cool Facts” list.
One relates to migration: The adults, unlike most songbirds, migrate to their wintering grounds before molting, while young birds molt before and during autumn migration. This is likely tied to those arriving early being more successful.
The other cool fact is that one least flycatcher nest was lined with dragonfly wings. I guess we can add dragonflies to the list of least flycatcher prey.