Bluebird numbers on the rise

Bluebird numbers on the rise

“When Nature made the bluebird she wished to propitiate both the sky and the earth, so she gave him the color of the one on his back and the hue of the other on his breast, and ordained that his appearance in the spring should denote that the strife and war between these two elements was at an end. He is the peace-harbinger; in him the celestial and terrestrial strike hands and are fast friends.” The Blue Bird by John Burroughs, from Wake Robin, published in 1871

A recent article in Connecticut Wildlife Magazine about the conservation success of the eastern bluebird caught my eye. Written by Brian Hess of the Connecticut Department of Energy and Environmental Protection (CT DEEP) Wildlife Division, the article describes conservation efforts of one of our region’s most popular birds.

“Like much of the wildlife in Connecticut, the fate of eastern bluebirds has ebbed and flowed with European colonization of eastern North America, the incursion of invasive species and attention of conservation actions,” Hess wrote.

No other bird frequently visiting our property gets as much attention and adulation as our resident bluebirds. The flash of their vivid blue backs and soft reddish-brown breasts is a sight to enjoy, as is the gentle murmurings of their song.

For years I lived at locations which were not suited to attracting bluebirds. There were too many trees and not enough open space for hunting their preferred food of invertebrates. Our property in Putnam is six acres with a dozen mature sugar maples near the house and then five acres of adjoining pasture and fields dominating the back lot. Bluebirds are cavity nesters, so I put up a bluebird nesting box in the open area soon after moving in, which was followed by a second and then a third. I was determined to attract bluebirds.

The biggest challenge for a bluebird’s nesting success is the very aggressive English sparrow, also known as the house sparrow, who is a competitor for the same cavity or nest box the bluebird seeks.  According to Hess, throughout the middle of the 19th century, immigrants of European descent imported and released thousands of house sparrows with 40 pairs released in New Haven in 1867. The introduction of European bird species also included the European starling. The sad result is the spread of these birds across North America, with European starlings and house sparrows now numbering in the hundreds of millions.

Determined to succeed with nesting bluebirds on our property, I have waged war on the house sparrow. I keep a close watch on our nesting boxes and dissuade pesky house sparrows by letting them build a nest in one box and destroying it before eggs are laid, causing them to rebuild and rebuild again while the bluebirds are busy with a brood of their own in one of the other nest boxes. (Note: House sparrows are a non-native invasive bird species and are not protected by the Migratory Bird Treaty Act.)

This year has been successful for our bluebird pair. In June they fledged three chicks in the nesting box near the raspberry bushes. I cleaned out the old nest hoping the pair would build a new nest and start again, but mister and mistress house sparrow had other ideas and quickly took up residence. The bluebirds were happy to relocate and built a new nest in the box at the edge of the back field. Soon there were eggs and at this writing four hungry chicks will soon be out and on the move. The season is still young, and I am hoping our bluebirds go for three broods. That would be a first for me. I’ll keep on the lookout for the house sparrows, but so far they seem to have moved on to other abodes.

I have been looking into new designs for nesting boxes that deter the sparrow but are fine for bluebirds. I hope to include some of these newer designs next year. Thankfully I have yet to experience the horrific predation that house sparrows can inflict on bluebirds. They are known to kill nesting adults and chicks and will build their nest on top of the carcasses of the unwitting bluebirds.

The 19th century introduction of house sparrows and European starlings wasn’t the only thing threatening bluebirds. They also suffered loss of their preferred habitat due to the decline in agriculture and the regrowth of forestlands. A more coordinated conservation effort was needed to aid these beautiful birds.

Thanks to countless volunteers, sympathetic landowners and organizations such as the North American Blue Bird Society and Sialis, the past 50 years have seen a rebound in the number of bluebirds. These groups have encouraged conservation through educational programs and the promotion of nesting boxes. There are even bluebird nest box trails and a network of volunteers helping to monitor them. You can find helpful information, as well as how to attract bluebirds and plans for bluebird nesting boxes, at the following websites:



North American Blue Bird Society:

At our property in Putnam we see bluebirds throughout winter. The species is a “partial migrant” with some birds moving south during the cold season and some keeping close to their breeding grounds. Our breeding pair prefers the latter, and we are glad to have them here all year. When invertebrates are hard to locate during the cold months, they will come to the hanging suet we put out. They prefer suet that is mixed with bits of seed and dried fruit. I have seen them foraging for sunflower bits under our bird feeder. They also search out several species of berry-producing native plants and shrubs for left-over gleanings. This year I planted three winterberry bushes with our bluebirds in mind.

Hess closes his article with this optimistic message, “Because our environment is so complicated, there are few straight-forward success stories in recovering species at risk. In a sea of bad news bluebirds offer hope of what might be possible when the interest of many align to help wildlife.”

We live in a beautiful place called The Last Green Valley National Heritage Corridor. When I see our bluebirds dashing about our backyard bringing caterpillars to their hungry brood, I am reminded again of the efforts of many in our region who have helped this beautiful bird rebound. I hope you’ll join me and others as we continue to care for, enjoy and pass on this place we (and bluebirds) call home.

Information for this column gleaned from Connecticut Wildlife Magazine April/March 2020 issue. It can be found on-line at:

Bill Reid is the Chief Ranger of The Last Green Valley National Heritage Corridor and has lived in the region for more than 35 years. He can be reached at





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