Do eastern bluebirds leave and come back?

Eastern Bluebirds Prepare for Fall, Leaving Questions About Their Journeys

Falmouth, Maine – As the leaves begin to turn, the Gilsland Farm Audubon Center is busy with a different kind of migration: the yearly cycle of the eastern bluebird (Sialia sialis). A new brood of young birds fledged from a nest box at the center just a couple of weeks ago, marking the end of a productive breeding season for the local population.

The question that often follows such a sight is where these bluebirds will go for the winter and whether they’ll return to Maine in the spring. The answer, it turns out, is as varied as the birds themselves.

A Patchwork of Movements

Eastern bluebirds are “partial migrants.” Some individuals travel south to escape Maine’s harsh winter, while others stay close to their breeding grounds. The furthest confirmed winter migration for a single bluebird covers roughly 1,300 miles, from Manitoba in Canada to Texas, according to records from the federal Bird Banding Laboratory. Those data come from licensed biologists who capture birds, attach unique metal bands to their legs, and log information whenever the bird is recaptured or sighted again. The band acts as a bird’s “social security number,” enabling scientists to track its life history.

Researchers note that birds that spend their summers in regions with severe winters are more likely to migrate. These migratory birds sometimes “leap‑frog” over resident birds, arriving further south before winter, while residents stay near their breeding territories.

How Long Do They Live?

The Bird Banding Lab also maintains a database of longevity records. The oldest documented eastern bluebird was banded in New York in May 1989 and was found dead in South Carolina in November 1999, giving it a confirmed lifespan of at least 10 years and six months. Scientists believe the true maximum age is probably higher, as it is unlikely that a very old bird would have been caught, banded early in life, and then found again at its maximum age.

Do Bluebirds Return Home?

Site fidelity, or the tendency of a bird to return to the same place each year, varies by region, sex, and breeding success. In southern populations, about 40% of bluebirds breed in the same location each year, whereas northern birds only return about 26% of the time. A study conducted in South Carolina found that male bluebirds were slightly more likely to return than females (44% versus 39%). Moreover, successful nesters were much more inclined to return (56%) compared with birds whose nests failed (15%).

The fate of the young is also influenced by their parents’ behavior. Once parents begin a new clutch, they often become aggressive toward the older chicks, forcing the fledglings to fend for themselves. Those young typically stay near their birthplace but must carve out their own territories as independent adults.

What’s Happening at Gilsland Farm?

The Gilsland Farm Audubon Center has a few pairs that have proven remarkably productive. One pair nesting in the orchard raised three broods over the course of the season and left shortly after the third group fledged. Another pair, the focus of a recent question from Alice and Tom Davis of Saco, had its last brood only a couple of weeks ago and remains on the property. Observers suspect that these birds will depart soon for the winter.

After October, the center’s activity tends to dwindle, but the arrival of new bluebirds is common. Whether these newcomers are coming from farther north or are local birds that have stayed to hold on to their breeding territories is still a mystery. As the winter settles in, visitors and birdwatchers are encouraged to keep a close eye on the skies over Gilsland Farm and the surrounding areas.

Learn More About Bluebirds

The Maine Audubon Society invites the public to explore birding opportunities throughout the state. Naturalists, including staff member Doug Hitchcox, lead free bird walks each Thursday morning at 8 a.m. at Gilsland Farm. For more information, or to submit a question about wildlife, residents can email [email protected] or visit www.maineaudubon.org.

While the bluebirds’ exact winter routes remain an open question, their presence each fall is a reminder of the dynamic life cycles that unfold right in our backyard and in parks across Maine.