Swallows are a family of perching birds that are found all around the world on all continents except the polar regions. These birds are highly adapted to aerial feeding and have a distinct appearance. Swallows have trouble walking but are very strong fliers and like to eat insects they catch while in flight.
A black and white drawing of a Tree Swallow
Illustration of a Tree Swallow
NPS/Intern Tristan Thomas

Tree Swallow (Tachycineta bicolor)

• When migrating or wintering Tree Swallows sometimes form giant flocks that can have as many as thousands of birds in it. These giant flocks gather about an hour before sunset and form a dense cloud above their roost site and they then swirl around like a living tornado.
• Tree Swallows were given their names from their habit of nesting in tree cavities but they also like nest boxes.
• Tree Swallows take baths by flowing low over the water and skimming their bodies against the surface. They then rise quickly while shaking off the water droplets.
• They love to eat insects but will also eat other small animals and plants during bad weather when prey is unavailable.

Identification Information

• Size: Sparrow sized or smaller (Extra Small/Small)
• Color: Adult males are a blue/green on their backs with black feathers and thin black mask across their eyes. Females are duller in coloring with more brown in their upper parts. Young Tree Swallows are completely brown on top.
All of the above information is an abbreviated version of information gathered from the Cornell Lab of Ornithology. Please visit their website for more in-depth bird information.

Last updated: September 16, 2019

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Harpers Ferry National Historical Park
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