The bluebird has long been
a favorite bird in North America. It is loved for its beautiful blue coloring,
as well as, its gentle disposition and its pleasing voice. The bluebird is the
symbol of love and happiness in many of our songs.
Once a common bird, the
bluebird was numerous even in urban residential areas, but it has seen a decline
in numbers, with the Eastern Bluebird losing up to 90 percent of its population.
A number of factors, such as insecticides, the destruction of their habitats,
predators, and competition from other birds have contributed to this decline.
The destruction of some of their food supply, such as the wild holly berries
used in Christmas decorations, has also been a factor.
Those who love the bluebird
have begun a massive effort to save it through the erection of thousands of
nesting boxes appropriate for this species and predator- and competitor-proof.
And the bluebird is beginning to reappear in areas where these nesting boxes are
There are three species of
bluebird: Eastern, Western, and Mountain, and they belong to the thrush family.
The Eastern Bluebird (Sialia sialis) breeds in every state east of the
Rocky Mountains. It is bright blue with a rusty red breast similar to the
robin's. The Western Bluebird (Sialia currucoides) breeds in the western
states from Canada to Mexico and east to Colorado. It has a blue throat, and the
red color extends to its upper back. The Mountain Bluebird (Sialia
mexicana) breeds in the Northwest, east to the Dakotas, and north into
Alaska. It is entirely blue, with a white underbelly.
Bluebirds are primarily
insectivores, eating many insects considered pests by man: cutworms,
grasshoppers, and flying insects. They supplement this diet in fall and winter
with wild berries and may starve if snow covers the ground and berries are
The spring courtship rites
of the bluebird are among the most enjoyable to witness. The male selects a
suitable nesting cavity and devotes all his energy to luring a female to it with
song. He sings and sings, as the female sits passively by, enjoying his effort.
When she inspects the nesting place, he interprets her interest as acceptance
and his song becomes even more passionate. But the final selection of the
nesting place is hers, and if she finds his choice unacceptable, he must search
for something better.
The female builds a nest of
dry grass or pine needles and other plant material. The nest is typically about
three to four inches deep. Here the Eastern Bluebird lays an average of three to
five clear blue eggs (though occasionally they may be white), with the western
and mountain species adding one or two more. They hatch in two weeks and the
baby birds leave the nest in 15 to 20 days, ready to fly and soon able to feed
themselves. By fall
the pair has raised two or three broods of young and may migrate south if their
food supply runs out or it gets too cold.
The bluebird's chief
competitors among other birds are the house sparrow, or English Sparrow, and the
starling, both of which like the same type of nesting space. Sparrows will break
the bluebird's eggs in a nest, or move into the nest during the winter when the
bluebird has migrated. They will even peck the baby or adult birds to death,
with the bluebird often unable to defend itself. Starlings will drive bluebirds
out of an entire area and occupy every available nesting cavity, unless man
What can we
We can assist in the return
of this lovely bird by providing suitable habitats, winter shelter, and food
supplies. Plants that bear berries throughout the winter (bittersweet,
hackberry, dogwood, American holly, privet, bayberry, sumac, and others) will
provide food for not only bluebirds but many other species. Winter roost boxes provide shelter
in the coldest season for many birds. In areas where bluebirds find sufficient
food, they may stay all year, but a roost box will allow them warmth on cold
nights. And specially
designed bluebird houses, with predator guards on the entrance to keep out
squirrels, raccoons, and competing birds, will give the bluebird a safe place to
live and rear its young. Nests of sparrows and other competitors must be cleaned
out of the bluebird house on a regular basis.
What is a
People sometimes create a
"bluebird trail" by hanging many bluebird houses in an area, about 100 yards
apart, to give the bluebirds an abundance of housing. They are often placed on
fence posts, giving the appearance of a "trail." Tree swallows often find bluebird
houses to their liking as well, and this problem can be lessened by hanging two
houses back to back, even on a post or close to each other. Two bluebirds will
not nest near each other, so this gives the swallows one house and the bluebirds
the other. The swallows will even help protect the bluebirds from other