The Eastern Bluebird

Welcome to the wonderful and delightful world of the Eastern Bluebird in Florida. The Eastern Bluebird, whose official Latin name is Sialia sialis, is a member of the Thrush family.

There are three species of bluebirds: Eastern, Mountain and Western.

The Eastern Bluebird is found throughout the United States east of the Rocky Mountains from the southern part of Canada down into Mexico and Central America. That includes all of Florida. Bluebirds have been reported from Escambia to Nassau counties across the northern part of the state, and as far south as Key West in Monroe County. (ebird.org/view and explore data/maps/select species – Eastern Bluebird/continue/change location/Florida/entire region/continue).

If you haven’t seen an Eastern Bluebird in Florida it’s probably because you haven’t been looking! However, it is highly unlikely to see the other two members of the bluebird family in Florida.

A Brief History and The Need for a Helping Hand

The Western Bluebird (Sialia mexicana) is found in the western part of North America from southern Canada down into Mexico. The Mountain Bluebird (Sialia currucoides) also is found in the western part of North America, but its range extends from central Alaska to southern Mexico. Some Eastern Bluebirds stay in an area year round. Others, like human “snowbirds,” move south during colder weather. One study reported that in October and November, some Eastern Bluebirds from further north move into northwest Florida.

This study was complemented anecdotally by the increase in bluebirds reported seen during the winter months at a retirement community in Clay County, FL.

A Beautiful Little Bird

The Eastern Bluebird is a beautiful, medium sized songbird approximately 7 inches from the tip of its beak to the tip of its tail. What the Eastern Bluebird lacks in size it makes up for in color. The male Eastern Bluebird is bright blue on the top of its head, back and tail, with a contrasting reddish-orange chin, chest and flanks. The belly and undertail coverts are white.

The female Eastern Bluebird is not as brilliant as the male, but just as beautiful, nevertheless. The top of her head, back and tail are battleship blue. Her chin, throat and flanks are a pale orange. Like the male, she has a white belly and undertail coverts.

Add a beautiful song to eye-catching colors, and you have a bird which has become a favorite among poets and songwriters from Henry David Thoreau to Paul McCartney when they want to describe love, joy, happiness and beauty.

America’s love affair with bluebirds dates back to Colonial days when immigrants began clearing the forests to create homesteads and farmlands. As the Colonists cleared the land they unwittingly became one of the bluebirds’ best friends.

Eastern Bluebirds thrive in open, grassy areas which have been cut or mowed, are clear of underbrush and have widely scattered trees or high bushes to use as a perch. (In modern times, bluebirds frequently perch on telephone wires or fences.) Depending on the time of year, 68 percent of the bluebirds’ annual diet consists of insects. They often are seen swooping down from their perch to catch a grasshopper, beetle or other bug on or near the ground.

Settlers soon realized that bluebirds are secondary cavity nesters. That means a bluebird’s beak – unlike that of some birds, such as the woodpecker – isn’t strong enough to chisel out its own nest cavity in a tree. Instead, bluebirds rely on cavities created by nature, other critters or humans. Putting two and two together, settlers soon began putting out nest boxes to attract bluebirds in order to help combat the insects feasting on the crops in their fields and gardens. In the days before pesticides, farmers appreciated the bluebird’s help controlling insects. (Even today research is being conducted to determine the effectiveness of using bluebirds to help control insects on organic farms.)

During this time, the Eastern Bluebird population increased. It has been reported that in the eastern part of this country during the early 1800’s bluebirds probably were as common as the American Robin.

Unfortunately the good times eventually came to an end. In the mid to late 1800’s, the Eastern Bluebird received a one-two avian punch that sent the populations into a tailspin.

In 1850-1851 (English) House Sparrows were brought into the United States from England and released in Brooklyn, NY. Those were the first of many House Sparrows introduced into the United States in subsequent decades. Ironically, one of the reasons the House Sparrow was brought into the United States was to help control an insect infestation damaging trees in New York City’s Central Park. Unfortunately, unlike the insectivorous bluebird, 96 percent of an adult House Sparrow’s diet consists of grain and weed seeds.

The House Sparrow population exploded and quickly began having an injurious impact on native cavity nesting birds such as bluebirds. Nesting sites once available for bluebirds were invaded by House Sparrows. House Sparrows don’t just evict the bluebird from the nest site; House Sparrows will destroy the eggs or kill any adult

Good Intentions, Bad Results

In The Beginning…

and nestling bluebirds they can trap in a nest site. As if battling House Sparrows weren’t hard enough, the Eastern Bluebird also had to contend with the European Starling. In 1890 European Starlings were released in New York City’s Central Park. Starlings were included in an illogical effort to introduce into the United States all the birds mentioned in Shakespeare’s works. The starling apparently was the only species to survive, and survive and multiply it did.

Starlings, like House Sparrows, are aggressive birds which will take over nesting sites from the Eastern Bluebird. Starlings and House Sparrows now are counted among the most numerous songbirds in America. Because of their sheer numbers they can have a negative impact on native competitors such as bluebirds. Fortunately starlings are larger than bluebirds and cannot get into a properly designed bluebird nestbox.

The Eastern Bluebird also has been at the mercy of the weather. Severe storms and hurricanes – particularly during the breeding season – can have a severe but short-term impact on the bluebird population.

A Troubled History

The history of the Eastern Bluebird has been a series of good times, bad times. The 1900’s were no different. In the beginning of that century, the House Sparrow population apparently peaked, as the country began moving out of the horse-and-buggy days into the era of gasoline-powered automobiles and farm machinery. This meant less food for House Sparrows, which thrived on loose grain found around farms and in animal droppings.

But the good news was accompanied by bad news. The Eastern Bluebird population also was peaking about this time. Although bluebirds still were a common sight in some areas during the first decade or so of the 1900’s, the seeds for a precipitous decline already were being sown. As the years rolled by farms in many areas were abandoned and reverted back to forests. In other areas entire forests disappeared as loggers clear-cut every tree in sight.

The accidental importation of the fire ant in the 1930’s compounded the bluebirds’ problems in the South. Fire ants still represent a major problem on bluebird trails in Southern states. When fire ants get into a nest, they can reduce a baby bluebird to a skeleton in a few days. It is not a pretty sight to find nestlings in a bluebird nestbox one week, then come back the following week and find nothing but bones. When a fire ant mound is found near a nestbox pole, it could be only a matter of time before the nestbox is invaded and the nestlings eaten alive. One solution is to spread ant poison around the mound. Where this has been done, the nestlings have survived and there has been no visible evidence that the ant poison has had an adverse affect on the birds.

The decision to use poison to control fire ants is made despite the knowledge that increased use of pesticides, particularly DDT, made life even more hazardous for bluebirds in the latter half of the 1990’s. Pesticides were used to kill insects, which were the main item on the bluebird’s menu. The result was indirect poisoning of the bluebirds.

As a result of all these problems the population of Eastern Bluebirds was estimated to have dropped 90 percent between the 1920’s and the 1970’s. The News Wasn’t All Bad

Some concerned individuals recognized that the bluebird was in trouble. Nestboxes have been used since Colonial days to attract bluebirds. But it wasn’t until the 1920’s that Thomas Musselman, of Quincy, IL, reportedly came up with the idea of putting up “bluebird trails” which extended beyond local boundaries. This concept took flight and has proven to be a major factor in the survival of the bluebirds.

The continued placement of bluebird nestboxes becomes even more important in states such as Florida, where an ever-increasing population results in an ever-increasing loss of suitable habitat.

Whether a “bluebird trail” consists of one nestbox or a hundred nest boxes, it is important that the needs of the birds are given priority over the personal preferences of the individual. It must be remembered that first and foremost, nextboxes are for the birds, not for the people putting them up.

That being said, what do the bluebirds want?

Basically there are only two main things to keep in mind when putting up a bluebird box: (1) A good nestbox (2) in the right location.

It has been said that there are as many different nestbox styles as people who maintain bluebird trails. Though that is an exaggeration, it underscores the fact that there is no one “perfect” nestbox, only nestboxes that bluebirds are attracted to and use. That being said, there are certain fundamental requirements that all nestboxes should meet.

One Nestbox Bluebirds Like

See House Plans for one nestbox, which has received the “stamp of approval” from bluebirds in Clay County, FL.

Where to Learn More

Hopefully this brief review of the history of the Eastern Bluebird and the importance of putting out nestboxes to help preserve a bright future for these beautiful native songsters will inspire you to create your own “Bluebird Trail.” Remember, every bluebird trail starts with the first box.

For those people who would like more information on a wide range of subjects related to the Eastern Bluebirds, there are many excellent websites on the Internet. They include:

North American Bluebird Society

SIALIS

The Bluebird Box (Audubon Society of Omaha)

Bluebird-L Reference Guide @ Cornell

The Birdhouse Network

Life Histories for Familiar North American Birds by Arthur Bent

Summary of biological data, distribution, etc for bluebirds.

Patuxent Bird Identification InfoCenter

Searchable Ornithological Research Archive

The Florida Bluebird Society wishes to thank these sites for the information which was contained in this article.

The Florida Bluebird Society also thanks Wendell Long Photos for permission to use the photographs in this article.

You also can also contact the Florida Bluebird Society at floridabluebirdsociety@yahoo.com or at floridabluebirdsociety.com