Tree swallows are a small migratory songbird found widely across North America. They are known for their bright iridescent blue-green upperparts and clean white underparts. Tree swallows get their name from their habit of nesting in cavities in dead trees, nest boxes, and other manmade structures. Understanding where tree swallows like to live and their habitat preferences can help people provide habitat for these birds.
What kind of habitats do tree swallows prefer?
Tree swallows thrive in open habitats near water, fields, and wetlands. They prefer areas with a mix of open fields, water sources like rivers, lakes, or ponds, and dead trees or nest boxes for nesting. Some key habitat features that tree swallows seek out include:
- Open fields and grasslands – Tree swallows enjoy hunting for insects over open areas.
- Wetlands – Close proximity to water provides insects that tree swallows feed on.
- Dead trees or nest boxes – Tree swallows nest in cavities, requiring dead standing trees or artificial nest boxes.
- Perches – Tree swallows use perches like bare branches in dead trees to rest and scan for insects.
While tree swallows originally nested in natural tree cavities, they have readily adapted to using artificial nest boxes provided in appropriate habitat. Putting up nest boxes for tree swallows is a great way to attract them and provide critical nesting habitat if natural nest sites are limited.
What areas and regions do tree swallows live in?
Tree swallows live across most of North America. Their breeding range extends from Alaska across Canada and the northern United States to the Atlantic coast. Their winter range includes the southern United States, Mexico, Central America, and the Caribbean islands.
Some key areas tree swallows inhabit include:
- Northern United States – Throughout northern states from Maine to Washington.
- Southern Canada – Across southern Canadian provinces.
- Coastal regions – Along the Atlantic, Pacific, and Gulf coasts.
- Central America – Overwintering grounds along the Pacific coast.
Tree swallows generally avoid dense forest and desert environments. They are most widespread in areas with a mix of open and wooded habitats and close proximity to water.
What elevation ranges do tree swallows live at?
Tree swallows can be found from sea level up to elevations of 10,000 feet (3,000 m). However, they are most abundant at lower elevations under 5,000 feet (1,500 m).
Some patterns in tree swallow elevation ranges include:
- Coastal areas: At sea level.
- Plains and grasslands: Up to around 3,000 feet (900 m).
- Mountain valleys: Up to around 7,000 feet (2,100 m).
- High mountain nesting: Up to 10,000 feet (3,000 m).
Higher elevation populations are generally limited to valleys and open mountain areas. Tree swallows may temporarily fly over high mountain peaks during migration, but do not typically breed or reside in dense, high elevation forests.
Do tree swallows live in urban or rural areas?
Tree swallows can thrive in both rural and urban/suburban environments as long as their basic habitat needs are met. They readily nest in nest boxes and adapt well to human-altered areas.
Some differences between rural and urban tree swallow habitats:
Rural | Urban/Suburban |
---|---|
Natural water sources like ponds, lakes, rivers | Man-made water sources like ponds, fountains, drainage ditches |
Dead trees for nesting | Nest boxes provided in yards, parks, golf courses |
Large open meadows and fields | Smaller parks and open spaces |
One advantage of urban areas is ornamental trees and shrubs that provide berries for late summer food sources.
What types of nesting sites do tree swallows prefer?
Tree swallows nest in cavities, traditionally using natural tree cavities or old woodpecker holes. They also readily use artificial nest boxes made for their use. Ideal nesting sites for tree swallows have these features:
- Cavity with adequate interior size – At least 4 inches wide x 5 inches deep (10 x 13 cm).
- Entrance hole 1 1⁄2 inches across (3.8 cm).
- Located 5-15 feet above ground.
- Protected from predators and elements by tree trunk/box structure.
- Clear flight path to entrance hole.
In natural settings, tree swallows compete for nest sites with other cavity-nesting birds. Proper nest box placement and density helps reduce this competition.
What materials do tree swallows use to build their nests?
The nests tree swallows construct inside their nesting cavities are relatively simple. Nests consist of these basic materials:
- Grasses – Long grasses form the base and structure.
- Feathers – Collected feathers line the inner cup.
- Hair – Animal hair provides insulation.
- Mosses – Mosses may be used in small amounts for padding.
Tree swallows build their nests on top of the layer of wood chips left over from years of previous use. They may include shed snake skins in their nests to reduce parasitism.
What trees do tree swallows nest in?
Tree swallows use a variety of dead trees and snags for nesting. Common nest trees include:
- Aspen
- Birch
- Maple
- Oak
- Pine
- Poplar
- Spruce
- Willow
The most important factor is a tree with an appropriately sized cavity. The species of tree is less important. Tree swallows readily use nest boxes wherever they are provided if natural sites are limited.
How do tree swallows interact with other bird species?
Tree swallows interact with other species in several key ways:
- Competition for nest sites – Tree swallows compete for nest cavities with chickadees, nuthatches, bluebirds, and other cavity nesters.
- Mixing in feeding flocks – Tree swallows mix with other swallows, swifts, and aerial insectivores when feeding.
- Mobbing predators – Tree swallows mob potential predators like crows, jays, and raptors near the nest.
- Nest parasitism – Brown-headed cowbirds sometimes lay eggs in tree swallow nests.
Properly spaced nest boxes can help reduce competition. Careful monitoring is needed if cowbird nest parasitism is an issue.
Conclusion
In summary, tree swallows thrive in open habitats near water across much of North America. They nest in cavities in dead trees and readily accept nest boxes. Tree swallows interact with other species when competing for nest sites, gathering in feeding flocks, mobbing predators, and dealing with brood parasitism. Understanding where tree swallows live and their habitat needs can help efforts to provide habitat and monitor populations of these iconic aerial insectivores.