Nest Boxes and Structures for Wildlife

Eastern bluebird at a nest box.

Many species of wildlife are attracted to backyards and woodlots when artificial nest structures are available. Wildlife use a variety of man-made structures for nesting, sometimes to the disappointment of people. Squirrels and bats may take refuge in an attic, raccoons in the garage, or swallows under the porch roof. Birdhouses have been readily accepted by many natural cavity-nesters, and the placement of houses in your backyard can be an effective way of providing for a number of resident birds.

The supply of nest sites available to cavity nesting wildlife has declined in certain areas due to the clearing of land for development, the removal of snags (standing dead trees) during agricultural and forestry operations, the use of treated fence posts that do not develop cavities, and competition with introduced species, such as the European starling and house sparrow. Nest boxes have been used successfully as a wildlife management tool where surveys have shown that virtually no natural nest sites occur. In Connecticut, eastern bluebird, wood duck, and osprey populations have increased, partially due to the erection of nest structures in suitable habitat. Nest boxes are used by many other wildlife species, such as gray and flying squirrels, screech and barn owls, hooded mergansers, house wrens, and kestrels.

Nest boxes should be properly designed, erected, and maintained for beneficial results. They should also be durable, predator-proof, weather-tight, lightweight, and economical to build. Boxes for a target species should be constructed with the correct dimensions, placed at the appropriate height above the ground and installed in suitable habitat. When constructing nest boxes, do not use pressure treated lumber and do not paint or stain the inside of the box. Whether there are one or 1,000 boxes, they should be inspected annually for needed repairs, replacement, and cleaning. Keeping an inventory of the location of each box and a history of wildlife use will not only provide important information, but will also prove to be a rewarding experience.

Bluebird Nest Box Plans

Bat House Plans

American Kestrel Nest Box Plans, courtesy of Art Gingert

Find plans for Nest Boxes and Nest Structures for a variety of birds through Nest Watch, The Cornell Lab of Ornithology

Dimensions for Nest Boxes and Platforms

Species

Floor

Entrance
Diameter

Depth

Entrance
Above
Floor

Height
Above
Ground

Wood Duck

9" x 10"

3 1/2" x 4"

25"

18"

3-20'(a)

Hooded Merganser

9" x 10"

3 1/2" x 4"

25"

18"

3-20'(a)

Kestrel

8" x 9 1/2"

3 1/4"

12-15"

9-12"

20-30'

Barn Owl

10" x 18"

6"

15-18"

4"

12-18'

Screech Owl

8" x 8"

3"

12-15"

9-12"

10-30'

Saw-whet Owl

6" x 6"

2 3/4"

10-12"

8-10"

12-20'

Red-bellied Woodpecker

6" x 6"

2"

12-15"

10"

10-20'

Downy Woodpecker

4" x 4"

1 1/4"

9-12"

6-8"

6-20'

Hairy Woodpecker

6" x 6"

1 1/2"

12-15"

9-12"

12-20'

Flicker

7" x 7"

2 1/2"

16-18"

14-16"

6-20'

Great Crested Flycatcher

6" x 6"

2"

8-10"

6-8"

8-20'

Tree Swallow

5" x 5"

1 1/2"

6"

5"

6-16'

Black-capped Chickadee

4" x 4"

1 1/8"

8-10"

6-8"

6-15'

Tufted Titmouse

4" x 4"

1 1/4"

8-10"

6-8"

6-15'

White-breasted Nuthatch

4" x 4"

1 1/4"

8-10"

6-8"

12-20'

Carolina Wren

4" x 4"

1 1/8"

6-8"

6"

6-10'

House Wren

4" x 4"

1 1/8"

6-8"

6"

6-10'

Eastern Bluebird

4" x 4"

1 1/2"

8"

6"

5-6'

Prothonotary Warbler

5 1/2" x 4"

1 1/4"

8-10"

6-8"

6-15'

Gray Squirrel

10" x 11"

4"(b)

24"

20"

12-30'

Flying Squirrel

6" x 6"

1 1/2"

8-10"

6-8"

10-36'

Open Platforms

Phoebe

7" x 8"

8-12"

8-12'

Barn Swallow

7" x 8"

6"

8-12'

Robin

7" x 8"

8"

6-15'

(a) Height above water surface
(b) Entrance on side of box

Federal Aid in Wildlife Restoration logo and tagline.

Content last updated in August 2022.