Local Volunteers Boost Bluebirds, Monitor Nestboxes

Local Volunteers Boost Bluebirds, Monitor Nestboxes

A little one-ounce blue, orange and white bird is a good news environmental story, for a change. Amid what seems like never-ending doom-and-gloom reports about climate change, biodiversity loss, deforestation and species declines and extinctions, the eastern bluebird is a comeback story and some Northern Virginians are helping tell the story.

In the early 20th century, eastern bluebird populations fell in North America, but since 1966, they have been rising, according to the North American Breeding Bird Survey.  Experts credit human-installed nest boxes as a major factor in the birds’ rebound.

Eastern bluebirds are cavity nesters. Females typically build nests in natural cavities like old woodpecker tree holes. Pairs raise two to three broods in the spring and early summer.

Local Volunteers

Since 1982, volunteers have maintained and monitored around 25 bluebird boxes at Huntley Meadows Park. The park’s most recent nestbox data show that in 2022 the bluebirds there laid 42 eggs and the success rate was 79 percent, meaning 79 percent of the young birds born fledged, grew up to leave the nest. This year, ten volunteers check the boxes weekly.

“The bluebirds are not having a problem around here. It’s certainly working well at Huntley Meadows,” said Brooks Long, the park’s Natural Resources Assistant.

AHS’s New Bluebird Trail

The American Horticultural Society (AHS) this year created its first bluebird trail at its Mount Vernon headquarters with eight boxes. Nestbox volunteers were encouraged when on April 9 in one nest box they found five bluebird eggs and the next week, three eggs and two young. On May 3, Donna Stauffer and Jerry Nissley with the Fairfax County Master Naturalists, in doing their weekly check, found one side of that box unscrewed and open and nothing inside. “It looks like a human predator,” said a dejected Nissley. 

No one is certain what happened or when. On May 11, volunteers found four bluebird eggs in one box and are hopeful the bluebird will lay a fifth in this nest. 

AHS and volunteers are trying to prevent non-native house sparrows and European starlings from using the boxes so before nest-building begins again, they are stuffing a cloth plug in the boxes’ openings. The house sparrow was introduced to New York, in 1850, according to the Sibley Guide to Birds. People brought the European starling in 1890. Both have spread all over North America, sometimes displacing native cavity nesting birds like bluebirds.

Raccoons, snakes and opossums are also threats if they can get into or reach inside the boxes. Metal stovepipe and skirt baffles can block access by many animal predators. A wire mesh device around the box entrance called a “noel guard” also stops some predators from reaching inside.

“We are trying to restore native plants and wildlife, to help key species lost from our area recover,” said Stauffer. “This helps the whole ecosystem.” For her, helping bluebirds is an extension of Care for Creation, a program of Good Shepherd Catholic Church.


Since this is AHS’s first year managing bluebird boxes, some trial and error is inevitable, says Nissley. Virginia Bluebird Society (VBS) experts have helped volunteers reposition some of the boxes. Cornell University’s NestWatch website says that boxes should face east toward open habitat, be four to six feet high and 300 feet apart. Virginia Bluebird Society donated the boxes to AHS and staff installed them over the winter.

“Environmental stewardship stands as one of the American Horticultural Society’s four pillars” explained Katie Tukey, AHS Director of Development and Engagement. “The thriving wildlife at River Farm serves as a testament to our commitment to responsibly care for the land.”

Bluebird Facts

Eastern bluebirds like open fields with scattered trees and sparse ground cover, like pastures, agricultural fields, suburban parks and golf courses. They often perch on wires and fence posts.

Female bluebirds build the nests and lay two to seven blue eggs. The incubation period is 11 to 19 days and the young usually fledge within 21 days.

Bluebirds eat insects and in fall and in winter eat fruit, including the berries of mistletoe, black cherry, dogwoods, pokeweed, juniper and other plants. 

North America also has two other species of bluebird, a western and a mountain bluebird.

More Information

Bluebird Conservation, https://www.nabluebirdsociety.org/ 

Bluebird nestbox basics, https://nestwatch.org/ and https://www.audubon.org/news/how-build-bluebird-nest-box