Watercolor portrait of Tree Swallow (Tachycineta bicolor)

Tree Swallow

Tachycineta bicolor
Breeds across Canada and the northern an… Open areas near water Common Song

Learn to identify the Tree Swallow by ear. Master the "liquid, gurgling chirps and chitters over the water" phrase and tell it apart from similar species.

“twitter warble”

What the Tree Swallow sounds like

A small, streamlined swallow with iridescent blue-green upperparts and pure white underparts. The head and back of adult males shimmer blue in sunlight, while females are duller (brownish with some iridescent sheen). The bill is tiny and the tail is only slightly forked. Tree Swallows are often seen zipping over fields and water, flashing blue above and white below.

“liquid, gurgling chirps and chitters over the water”

How to tell it apart

Listen for: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. Often written as “twitter warble”.
Don't confuse with:The Violet-green Swallow — smaller and with a shorter, more forked tail. adults have bright green backs and purple rump, plus distinctive white patches on the sides of the rump and white that wraps over the eye – features tree swallow lacks.

Where you'll hear 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.

Arrives very early in spring – often by late February or March in northern states – before other swallows, thanks to its berry-eating ability. Breeding occurs from late spring into summer, often with one brood. By late summer and fall, huge flocks form in the evening, swirling in "tornadoes" before roosting in marshes. In winter, flocks of Tree Swallows in the South feed on wax berries and roost together in the thousands.

Similar species

Violet-green Swallow

Smaller and with a shorter, more forked tail. Adults have bright green backs and purple rump, plus distinctive white patches on the sides of the rump and white that wraps over the eye – features Tree Swallow lacks.

Northern Rough-winged Swallow

Uniform drab brown above and dirty gray-white below, without the crisp white belly and iridescent blue back of Tree Swallow.

Tree Swallow song FAQ

What does a Tree Swallow sound 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. Listen for the "liquid, gurgling chirps and chitters over the water" phrase.
How do I tell a Tree Swallow from a Violet-green Swallow by sound?
Violet-green Swallow: Smaller and with a shorter, more forked tail. Adults have bright green backs and purple rump, plus distinctive white patches on the sides of the rump and white that wraps over the eye – features Tree Swallow lacks.; Violet-green's underparts are also white, but its cheeks are white up to the eye (Tree Swallow's face is dark around the eye). Range barely overlaps (Violet-green is far West)..
When is the best time to hear a Tree Swallow?
Arrives very early in spring – often by late February or March in northern states – before other swallows, thanks to its berry-eating ability. Breeding occurs from late spring into summer, often with one brood. By late summer and fall, huge flocks form in the evening, swirling in "tornadoes" before roosting in marshes. In winter, flocks of Tree Swallows in the South feed on wax berries and roost together in the thousands.