Blue Beauties: Meet The Eastern Bluebird

Bluebirds are among those birds that seem to inspire affection almost everywhere. They have appeared in songs such as “Bluebird” by Paul McCartney & Wings, in well-known poems like Emily Dickinson’s “The Bluebird,” and in expressions that have become part of our culture, including “The Bluebird of Happiness,” a phrase associated with Edward Heyman’s 1934 song.

One of my favorite descriptions of these remarkable birds comes from the famous 19th-century naturalist and essayist Henry David Thoreau: “The bluebird carries the sky on its back.” With the male Eastern bluebird’s brilliant sky-blue plumage, it is easy to understand why this species has become such a beloved and beautiful bird.

How My Interest in Bluebirds Began

My deeper fascination with bluebirds began while I was developing teacher workshops through a program with the North Carolina Museum of Natural Sciences. Our team visited schools and worked with educators, helping them better understand their surroundings and become more confident about taking students outdoors to learn on school grounds. The activities covered many subjects, ranging from science to art.

With financial support from the National Science Foundation, we also assisted schools in developing small habitat areas that could serve as convenient outdoor classrooms and learning resources.

Why Nest Boxes Matter

One of the essential features of a bird-friendly habitat was a nest box designed for bluebirds. Their willingness to use these boxes may be another reason people are so fond of them. Although bluebirds naturally make use of cavities in trees and even old fence posts, they have also become very willing occupants of artificial nest boxes.

The Bluebird Boxes of Jack Finch

For schools that needed bluebird nest boxes, my preferred source was a remarkable man named Jack Finch, who lived in Bailey, North Carolina. Often known simply as Mr. Jack, he was a farmer, a practical naturalist and a passionate advocate for bluebirds.

Worried about the declining numbers of his favorite birds, Mr. Jack founded the nonprofit Homes For Bluebirds in 1973. The organization eventually constructed and sold tens of thousands of nest boxes bearing its name.

His nest-box design featured a 1.5-inch entrance hole. The opening was small enough to discourage competitors such as European Starlings from entering. A metal guard surrounded the entrance to stop woodpeckers, squirrels and starlings from enlarging the hole. The box also had a strong roof with an overhang and ventilation openings.

Mr. Jack often said that he had not truly invented the design himself—the bluebirds had. He experimented with numerous versions and ultimately kept the design that the birds appeared to favor most.

A Memorable Bluebird Encounter

One of the memories that has stayed with me from my early years at the museum happened one spring when I installed one of Mr. Jack’s nest boxes with a group of teachers. As we headed back toward the building, one of the teachers suddenly called out, “Look, there’s a bluebird on the box already!”

That kind of quick response is actually quite common. When a nest box is installed at an appropriate time of year, usually around February or March, local bluebirds may investigate it very soon afterward.

Mr. Jack died in 2006, but the durable Homes for Bluebirds boxes I obtained from him continue to provide nesting sites. Bluebirds still raise young in them year after year.

Nesting Begins in Spring

As I wrote this article in February, bluebirds had already begun visiting the nest box in our side yard. They generally start nesting sometime in March or April, carrying materials such as pine needles and dried grass into the box.

Both the male and female participate in constructing the nest. Once it is finished, the female begins laying eggs, producing one light-blue egg per day. Occasionally the eggs are white. A typical clutch contains four to six eggs.

After the final egg has been laid, the female begins incubation. The eggs hatch approximately 13 to 14 days later, with the young usually emerging within only a few hours of one another.

Caring for the Young

Both parents take part in feeding the nestlings. Their diet consists of a wide range of insects and spiders, along with the occasional small lizard.

The young birds also produce waste in a distinctive way. Their droppings are enclosed inside a gelatinous fecal sac, which the parents remove from the nest. The adults carry these sacs away and dispose of them at a distance, reducing the likelihood that predators will be attracted to the nest.

Leaving the Nest

Eastern bluebird young usually depart the nest 17 to 20 days after hatching. On fledging day, the parents may perch nearby while holding food and softly calling to encourage the young birds to make their first jump into the outside world.

The spotted juveniles can be surprisingly reluctant. Some may spend several minutes gathering the courage to take that first flight.

Even after the young have left the nest, the parents continue feeding them for another two to three weeks. The male may assume a larger share of this task once the female begins preparing another nest. Eastern bluebirds can produce two or three broods during a single nesting season.

What Eastern Bluebirds Eat

Eastern bluebirds have a varied diet that includes insects, spiders and fruit. I have watched the bluebirds around our home carry earthworms, beetle larvae, caterpillars and spiders back to their nest to feed their extremely hungry young.

When temperatures drop, their diet shifts more toward berries produced by native trees and shrubs. They appear particularly attracted to berries from red cedar, American holly and flowering dogwood.

Mr. Jack’s Dogwood Berries

Mr. Jack became especially interested in certain dogwood trees growing in yards throughout the region because some produced exceptionally large berry crops. He located these trees, cultivated them on his farm and eventually sold their berries as food for bluebirds.

He was the only person I ever encountered who collected dogwood berries, packed them in sawdust to reduce fungal growth and then stored them under refrigeration for sale as bluebird food.

His unusual method was remarkably effective. During winter, I could take several berries from the container, put them along the railing of my deck and soon have bluebirds arriving each morning. The largest group I ever counted on the deck was 14 birds, during a snowy January.

Additional Foods for Bluebirds

There are several other foods that can be offered to bluebirds, including suet, peanut butter during winter when combined with seed, and mealworms, whether fresh or dried.

Specially formulated bird-seed mixtures can also be useful, particularly those containing ingredients such as sunflower chips, suet pieces and dried fruits including cranberries and cherries.

Still, one of the simplest ways to encourage a wide range of birds to visit your yard is to create a habitat with plenty of native plant species. Providing a dependable water source as well as appropriate places for birds to shelter and nest can make the space even more attractive.

Creating a Bluebird Nesting Site

Anyone hoping to attract bluebirds has many nest-box designs to choose from, and building one at home is also relatively easy. The North American Bluebird Society offers a useful fact sheet containing numerous recommendations for constructing and placing bluebird nest boxes.

Providing the right habitat and nesting opportunities can bring the pleasure of observing and listening to one of North America’s most beautiful songbirds.

I will end with something Mr. Jack once told me during one of my visits. For him, the greatest pleasure was simply getting out of bed early, watching the sun rise and listening to bluebirds singing in the morning.