Choose the Right Birdhouse
Early spring is an ideal time to install birdhouses on your property
Because birds are already shopping around for nest sites, early spring is a good time to install backyard birdhouses. Not all birds nest and rear their young in houses. Those that do are species that seek out natural cavities in trees. Of some 85 North American species that nest in cavities, about three dozen also will nest in birdhouses.
Some of the most common backyard birds that use houses are chickadees, titmice, bluebirds and wrens. But you can attract other species depending on what kind of habitat you have in or near your yard—and the kind of box you put up. But first, you want to make sure you’re choosing a box that will help, not harm, your tenants.
Desirable nesting box features include:
Thick walls constructed of untreated wood for insulation.
Holes for ventilation and drainage.
An extended and sloped roof to keep out the rain.
A baffle to keep out raccoons, snakes, house cats and other predators that steal eggs and chicks. (One of the best baffles is made from a length of stovepipe.)
To maximize the number of birds that use your houses, certain nest box and habitat requirements must be met. Former National Wildlife Field Editor George H. Harrison, author of more than a dozen books on birds and backyard wildlife, provides the following tips:
House wrens and Carolina wrens are among the easiest birds to attract to birdhouses.
Requirements: 4” x 4” or 4” x 6” base, 8” high; hole: 1-1/8”, centered 6” above the floor; color: earth tone; placement: 5–10’ high on post or hanging in a tree.
Habitat: House wrens prefer their houses hanging from a small tree in the middle of a yard, or along the border of an open yard. Carolina wrens will go into a birdhouse that is well hidden in natural habitat.
All three bluebird species (eastern, western and mountain) will use birdhouses. Read more about setting up the right bluebird house.
Requirements: 5-1/2” x 5-1/2” x 10” high; hole: 1-1/2”, centered 6” above the floor; color: earth tone; placement: 5–10’ on post facing open field (preferring east, north, south, and then west facing directions).
Habitat: Bluebirds feed their young insects they capture in open, grassy fields. Their houses are most acceptable if placed on a post that faces, or is very near, an open field where they can find food.
Chickadees and Titmice
All species of chickadees and titmice will use birdhouses.
Requirements: 4” x 4” or 5” x 5” base x 8” high; hole: 1-1/4”, centered 6” above the floor; color: earth tone; placement: 4–8’ high in small tree thicket.
Habitat: These birds nest in dense natural habitat, such as thickets or stands of small trees.
A tree swallow will occupy a house of the same dimensions, location and color as a bluebird house, but the structure should be near water.
Habitat: Like bluebirds, tree swallows like to catch their insect food above open fields or water. Their houses should be placed facing this kind of natural habitat.
Purple martins use apartment houses that accommodate numerous families. They also like bird-houses made out of gourds.
Requirements: multiple apartments 6” x 6” x 6” each; 2-1/2” hole, 2-1/4” above floor; color: white; placement: 15–20’ high in the open, near water.
Habitat: Long sweep of grassy lawn or field should surround the martin apartment house as these birds hunt insects on the wing. A nearby utility wire may make the habitat even more attractive, because purple martins like to perch on or near their houses.
One of the few cavity-nesting ducks, wood ducks naturally nest in a tree cavity, but readily inhabit a house.
Requirements: 10” x 10” x 24” high; hole: 4” wide x 3” high (elliptical), centered 20” above the floor; color: earth tone; placement: on a post 3–5’ feet above open water or on a tree 12–40’ high near water; nesting material: 3–4” of wood shavings on the floor of the house.
Habitat: These tree ducks look for houses that are in trees on or near lakes, rivers or streams, to which they can lead their broods after the ducklings vacate the house.
Screech-owls are more common in backyards than most people realize, but because they are nocturnal, they often go unseen. They nest in summer or roost in winter in a birdhouse of the same dimensions and placement as that of a wood duck house. Roosting owls will sit in entrance holes at dusk.
Habitat: Birdhouses mounted on the trunk of a tree in a woodland of mature trees will bring owl occupancy either for nesting in early spring or for roosting in winter.
Because they often nest on ledges and downspouts on people’s houses, robins also may use a shelter that is a three-sided birdhouse.
Requirements: 6” x 6” x 8” high, open front; color: earth tone; placement: on side of building, arbor or tree. Phoebes and barn swallows will utilize this kind of shelter if placed under a deck for the phoebe, or in a barn for the swallow.
Habitat: The shelter should be mounted in a location surrounded by natural habitat, including mature trees and grassy lawns for hunting earthworms.
All woodpeckers nest in tree cavities, but northern flickers, red-headed woodpeckers and downy woodpeckers also may take up residence in bird houses.
Northern flicker requirements: 7” x 7” x 18” high; hole: 2-1/2”, centered 14” above the floor; color: natural; placement: 8–20’ high on tree trunk; nesting material: 4” of wood shavings on floor.
Red-headed woodpecker requirements: 6” x 6” x 15” high; hole: 2”, centered 6–8” above the floor; placement: 8–20’ high on tree trunk; nesting material: 4” of wood shavings on floor.
Downy woodpecker requirements: 4” x 4” x 10” high; hole: 1-1/4”, centered 6–8” above the floor; placement: 8–20’ high on tree trunk; nesting material: 4” of wood shavings on floor. Habitat: Because woodpeckers are woodland birds, they will be more likely to occupy birdhouses that are mounted on the trunks of mature trees in the middle of woodlands.
Birdhouses can be crafted in a workshop, or they can be purchased at a local bird supply store or National Wildlife Federation's catalog.
Adapted from “ Rooms to Let, Cheep, Cheep ” by Cynthia Berger, National Wildlife , February/March 2008.
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