Tree Swallow

Tachycineta bicolor

Order PASSERIFORMES - Family HIRUNDINIDAE

For complete Life History Information on this species, visit Birds of North America Online.

Tree Swallow, adult male

Tree Swallow, 1st year female

Description

Adults similar in appearance; yearling female and juveniles brown.

Song a series of repeated whistles and twitters.

Increasing slightly across most of range.

Hirondelle bicolore (French)
Golondrina invernal (Spanish)

Go here to take a look at what goes on inside a Tree Swallow nestbox, through the help of a Nest Box Cam provided by The Birdhouse Network at the Cornell Lab of Ornithology.
Outside of the breeding season the Tree Swallow congregates into enormous flocks and night roosts, sometimes numbering in the hundreds of thousands. They gather about an hour before sunset at a roost site, forming a dense cloud. They swirl around like a living tornado and as darkness approaches they then wheel low over the cattail marsh or grove of small trees. Large numbers drop down into the roost with each pass of the flock until the flock disappears.
The Tree Swallow uses many feathers from other birds in its nest. The feathers help keep the nestlings warm so they can grow faster. They help keep levels of ectoparasites, like mites, low too.
The Tree Swallow winters farther north than any other American swallow, and it returns to its nesting grounds long before other swallows come back. Its ability to use plant foods helps it survive periods of bad weather.

Robertson, R. J., B. J. Stutchbury, and R. R. Cohen. Tree Swallow (Tachycineta bicolor). In The Birds of North America, No. 11 (A. Poole, P. Stettenheim, and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, PA, and The American Ornithologists' Union, Washington, D.C.
Winkler, D. W. 1993. Use and importance of feathers as nest lining in Tree Swallows (Tachycineta bicolor). Auk 110:29-36.

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