Managing for wildlife:
Becoming a good wildlife manager requires learning the essentials about the animal
you plan to manage: where it lives, how it lives, and what it needs to survive, flourish
and reproduce. Creating a good Tree Swallow nest box project requires learning
some basic Tree Swallow characteristics and habitat needs.
What do Tree Swallows look like?
Tree Swallows, scientific name Tachycineta bicolor, are small songbirds. Like all
swallows they are fast, agile fliers that catch insects in their mouths as they fly.
Tree Swallows show the typical swallow body plan:
- Slender, streamlined bodies with short necks.
- Long, pointed wings.
- Small bills (but mouths that open wide).
- Very short legs with small feet.
Most adult male and female Tree Swallows can be told from other swallows by their:
- Shiny, iridescent blue upper body and head.
- Pure white throat and body underside.
- However females in the spring of their second calendar year of life (first nesting
season) show a mix of brown and greenish upper body feathers, like the second-
year female in Euan Reid's photo below.
- Juveniles, young Tree Swallows that have recently left their nests and have not
begun molt, are sooty gray above and white underneath. During this brief stage
they show no blue or greenish feathers. Photo below by John Gavin.
Where do Tree Swallows live?
- Tree Swallows nest from northern Canada and Alaska south through much of
the United States.
- The green areas of the map below show their main breeding range, but they
nest locally farther south.
- Field guides, local bird clubs, or state conservation departments can tell you if
Tree Swallows nest where you live.
- Tree Swallows winter from Florida and the Gulf Coast south into Mexico, Central
America, and the Caribbean (red areas of the map).
- Very specific range and occurrence data for Tree Swallows and other birds can
be found by exploring the eBird database.
What do Tree Swallows eat?
- All swallows feed mainly on insects that they catch in flight, as the Tree Swallow
in Robert Whitney's photo below is about to do.
- However, unlike other swallows, Tree Swallows eat certain berries, especially
those of bayberry and waxmyrtle. These berries become very important
sources of food in autumn and winter.
- Because they are such skillful fliers Tree Swallows are able to drink and bathe
on the wing, as the ones in Stephen Kolbe's photo below are doing.
What type of natural nesting habitat do Tree Swallow like?
- Tree Swallows prefer to nest near or in wetlands, such as marshes, swamps,
beaver ponds, and wet meadows.
- These wetlands are usually rather open for easy flight and have lots of the flying
insects Tree Swallows need to feed themselves and their young.
- Perhaps most important, wetlands often have nest sites Tree Swallows need.
Where do Tree Swallows build their nests?
- Tree Swallows are cavity-nesters. They nest inside holes in trees.
- However, Tree Swallows are unable to dig their own nest cavities. Under natural
conditions they must find an old woodpecker hole or a cavity in a dead tree if
they are going to raise any young. Photo below by Heather V. Hogg.
- Perhaps because there is usually a shortage of natural nest sites, Tree
Swallows quickly accept nest boxes, even ones far from water.
- And although they are not colonial like some other swallow species, pairs of
Tree Swallows will nest as close as 100' from one another if there are suitable
nest sites and a good food supply. This lets us create Tree Swallow projects
with multi-box grids.
- Tree Swallows are short-lived and may only get one or two chances to breed.
This, plus the shortage of nest sites, leads some Tree Swallows, like the one in
Cheryl Sutton's photo below, to try nesting in risky or inappropriate situations.
You are going to learn a tremendous number of other things about Tree Swallows, but
understanding these basics lets you take your next step: finding a good location for
your nest box project.
Click here for Next Step: Finding a Good Site.
Learn About Birds at Tree Swallow Nest Box Projects
|Creating Projects, Tree Swallow Basics, Finding a Good Site, Building Boxes,
Box Location, Pole Options, Mounting Boxes, Nest Box Grids, Predator Protection,
Bluebird Competition, Martin Competition, House Wren Damage, House Sparrow Damage