Tachycineta bicolor

Family: Hirundinidae

Tree Swallow (Tachycineta bicolor) is a sleek, fast-flying swallow of open country, wetlands, and field edges, recognized by its glossy blue-green upperparts and bright white underparts. In Minnesota, it is one of the more familiar spring and summer aerial insectivores, often seen skimming low over water or pausing briefly on wires, rails, or nest boxes.

For representative images and visual context, see the page: Tree Swallow in the Gallery section.

Description

Tachycineta bicolor is recognized by:

Size: small swallow, compact but broad-chested, with long pointed wings
Plumage: glossy blue-green upperparts contrasting sharply with clean white underparts
Bill: short, slender, and dark, suited to catching insects in flight
Structure: streamlined body, short neck, small head, and a slightly notched tail
Sex differences: sexes are similar, though females may appear slightly duller; juveniles are browner above with less gloss

The overall field impression is of a bright, cleanly patterned swallow that appears equally graceful in the air and striking when briefly perched.

Habitat and Range

Typical habitats include:

Marshes, ponds, and lakeshores
Open fields, grasslands, and agricultural edges
Nest box trails, fence lines, and wetland margins

Notes may include:

Widespread in Minnesota during the breeding season
Most often present from spring through late summer, with migration in early fall
Closely associated with open areas where flying insects are abundant
Frequently uses nest boxes, natural cavities, and open perches near water or meadow habitat

In Minnesota, Tree Swallows are especially characteristic of wet meadows, wildlife areas, and rural roadsides where open airspace and cavity nesting sites occur together.

Identification

Key features for field diagnosis:

Shape: compact swallow with pointed wings, a short bill, and a neat, streamlined outline
Plumage: dark iridescent upperparts and crisp white underparts create a very clean two-tone appearance
Bill: small and dark, usually not obvious at a distance
Voice: a soft, fluid series of chirps and chatters, lighter and less buzzy than many other aerial insectivores
Behavior: often glides and darts low over water or fields, then pauses upright on wires, rails, or posts

The combination of bright white underparts, glossy back, and poised perching posture helps separate the species from similar swallows in the field.

Behavior and Ecology

Often seen singly, in pairs, or in loose groups, especially over feeding areas
Breeds readily in cavities, including natural tree holes and nest boxes
Frequently patrols open airspace in buoyant, sweeping flight
Feeding behavior or diet includes:
- Primary food type: flying insects
- Secondary food type: occasional berries during cold weather or migration
- Seasonal food source: emergent aquatic insects around wetlands and ponds

Tree Swallows help define the spring and summer character of open wetland habitats, where motion, light, and insect activity all seem to gather in the same air.

Notes

Perched birds can appear surprisingly round-bodied in cool conditions, with feathers fluffed over the chest and sides
The glossy back may shift between blue and green depending on angle and light
Tree Swallows are often easiest to study when briefly resting on rails, wires, or nest boxes between feeding flights
In Minnesota, they are among the most familiar swallows around marshes, restored prairies, and shallow water basins

References

Cornell Lab of Ornithology – All About Birds
https://www.allaboutbirds.org
Audubon Field Guide
https://www.audubon.org
iNaturalist taxon page
https://www.inaturalist.org/