Acadian flycatcher adults have greenish-brown upperparts, a pronounced white eye ring, and buffy wing bars. The throat is grayish white, the upper breast pale olive, the lower breast white, and the belly yellowish. Late-summer birds with worn plumage may not be yellowish below. Fall molt occurs in Missouri, so the throat and belly may be yellowish before migration, making it easily confused with the yellow-bellied flycatchers passing southward through our state. Song is an explosive PEET-suh; the call is a more quiet peet. They also make a rapid pip pip pip pip pip around the nest.
Similar species: Missouri has 14 species of the tyrant flycatcher family; 5 of these are in genus Empidonax and are notoriously similar-looking. To make things more confusing, pewees (genus Contopus) look similar, too. Learning their different body shapes helps: pewees have relatively longer wings than Empidonax flycatchers, judged by how far the tips extend along the tail. Empidonax species have white eye rings, while pewees don’t. Compared to others in its genus, the Acadian flycatcher is generally larger and greener. Also keep in mind that the Acadian flycatcher is a common summer resident in Missouri, while the others, except for the willow flycatcher, are migrants. The willow flycatcher is less common than the Acadian and is more closely associated with water; it also has a different voice: an energetic, somewhat harsh FITZbew; also listen for the call, a distinct and rich wit. As noted above, Acadian flycatchers can resemble yellow-bellied flycatchers in fall. The Acadian has a longer, wider bill, and it has a whitish zone between its yellow belly and the olive chest. The yellow-bellied flycatcher has no white area between the yellow belly and olive chest.
Length: 5¾ inches.
Statewide. More common in the southern two-thirds of the state.
Habitat and Conservation
Deciduous forests, especially bottomland forests and moist ravines.
This flycatcher usually forages by fluttering and hovering within forest branches, snatching a wide variety of insects and spiders, often from the undersides of leaves. It also flies out to catch flying insects. Note that, compared to many other flycatchers, those in genus Empidonax typically take shorter foraging flights and, instead of sitting still upon returning to a perch, they typically flip their tails upon landing. This species sometimes snatches insects from the ground.
As a summer resident, common in southern Missouri and uncommon in northern Missouri.
Acadian flycatchers start arriving in Missouri in late April. Cup nests straddle between two forked branches of trees, away from the trunk, in mature deciduous woods, usually near water or in ravines, or in wetlands. The shallow nests are made of grasses, bark fibers, and other fine materials held together with spider webs or caterpillar silk. Often, leaves or other detritus dangle randomly below the nest from silk strands. Clutches comprise 1–4 eggs, which are incubated 13–15 days. Young begin to fledge another 13–15 days after hatching. Acadian flycatchers begin to leave our state in mid-September and have all departed by mid-October. Winters are spent in Nicaragua, Costa Rica, Panama, Ecuador, Colombia, and Venezuela. Acadian flycatchers can live to be more than 12 years old.
Acadia was the name of the French colony that existed in today’s eastern Canada and New England, established long before the British acquired the territory. It included parts of Quebec, the Maritime provinces, and some of Maine. (Longfellow’s poem “Evangeline,” which used to be required reading in schools, was based on Acadian culture.) Although genus Empidonax is now known to comprise some 15 species, at first it was thought to be a single species. The first specimen was found in Nova Scotia, so it was called the “Acadian flycatcher.” But after the various species were divided up, the bird called Acadian flycatcher today isn’t even known from that region.
It’s not surprising that Empidonax flycatchers were first thought to be all one species, back when birds were identified as dead specimens, using external characteristics. But ornithologists discovered that young flycatchers don’t learn songs; they are born with their songs genetically coded. With them, different songs mean different genes. So scientists learned to separate flycatchers into groups based on their songs. It turns out female flycatchers only breed with males singing the songs of their own species. Even if they look alike, they won’t breed with a male singing the “wrong” song. They don’t have trouble identifying each other!