What does the Tree Swallow song sound like?
Play the real Tree Swallow song, the "twitter warble", and learn what to listen for.
What the Tree Swallow song sounds like
Tree Swallows' "song" is a series of cheerful, liquid twitters and chirps given in a constant stream. It is a gurgling, high-pitched chatter that can be heard around nest sites at dawn. Both sexes may join in a quiet twittering chorus, especially during courtship or near the nest.
“twitter warble”
How to find the bird singing it
Open areas near water. Breeds in fields, meadows, lake shores, marshes, and forest edges – anywhere it can find tree cavities or nest boxes for nesting. Often associated with wetlands or ponds (hence the name "Tree" Swallow, as they nest in tree holes near water). During migration and winter, they gather in large roosts in wetlands, coastal marshes, and agricultural fields with available berry bushes.
- Blue-green Above, White Below: Adult male's upperside is a glossy metallic blue-green (can look black in poor light) and the entire underside from chin to undertail is snowy white. Females and juveniles are similar but upperparts are duller, often brownish with some iridescent tinges.
- Thin Black Eye Mask: The dark eye is set in a blackish "mask" on the face, especially in adult males. Because the face is dark and the throat is white, it can look like a thin black line through the eye. (Violet-green Swallows, by contrast, have a white patch that wraps around the eye.)
- Small Bill, Wide Gape: Extremely short and flat bill, appearing just as a little triangle. The mouth opens wide (gape) which is obvious when feeding chicks or snapping up flying insects – a classic swallow adaptation.
When you'll hear it
Spring
Arrives very early. By early March in many states, bright males are staking claim to nest boxes or cavities even with snow still on the ground. They often feed on bayberries if flying insects are not out yet. Pairs form and begin nesting by mid-late spring.
Summer
Breeding season. Pairs raise their brood in tree holes or nest boxes. You'll see adults constantly hunting insects in the air to feed their nestlings. Fledglings leave the nest about three weeks after hatching and are fed by parents for a short time after. By late summer, families begin to gather in groups and feed heavily on emerging insects over wetlands.
Fall
Massive roosts form. In late summer and fall evenings, hundreds of thousands can gather above marshes in the evening, performing swirling flight patterns before roosting. Many northern birds migrate to the Gulf Coast and beyond. In daytime, flocks roam, often mixing with other swallows, feeding over fields and bodies of water.
Winter
In the U.S., most stay in the far South or coastal areas (extreme SE, Florida, Gulf Coast, and parts of California). They gather in flocks and feed on berries (bayberry, wax myrtle) and any flying insects available. Roosting flocks in southern marshes can number in the hundreds of thousands, providing a spectacular sight in the evening sky.