2013 was a good year for native, cavity-nesting birds of Fairfax.
Births of animals at Frying Pan Farm Park are publicized and celebrated, but not all of the births in the park take place in the barn. There are Eastern bluebird (Sialia sialis) hatchings in nest boxes around the park, and sometimes the newborns are known only to the staff and volunteers who monitor those boxes.
There weren’t a lot of them around during the Great Depression. Bluebirds weren’t common in the 1930s. The usual problems — habitat loss and the introduction of non-native competition –depressed their population. The European starling and the English house sparrow, both aggressive species, competed with bluebirds for nesting cavities.
But people liked them, even crooned about them. Dame Vera Lynn sang about bluebirds over “The White Cliffs of Dover” in 1942. “Zip-a-Dee-Doo-Dah,” with the line “Mr. Bluebird on my shoulder,” won the 1947 Academy Award for Best Original Song. “Bluebird of Happiness,” recorded in 1945 by tenor Jan Peerce, was a worldwide hit.
More empirical, but just as romantic at the time, were bluebird enthusiasts. These folks installed and monitored nest boxes, and bluebirds recovered. We still use nest boxes, romantics that we are, to support the Eastern bluebird population in Fairfax County.
You can see bluebirds at Frying Pan year round, often near the park’s upper horse ring or the stormwater pond. During the spring and summer, they nest in cavities in trees and in the nest boxes. The small size of the entrance hole in the park’s 13 bluebird nest boxes keeps out the larger starling, and the monitors remove house sparrow nests to discourage them from using the boxes. The starlings and house sparrows still nest at the park in the farm yard. The bluebird boxes welcome all native species and are used by tree swallows, Carolina chickadees, tufted titmice, house wrens and others. You can learn more about the boxes and how they work by finding the display box along Frying Pan’s wagon ride path near the visitor’s center.
The bluebird monitors keeping an eye on those flirting birds in the boxes are park staff and volunteers with the Virginia Bluebird Society (VBS), a 17-year-old non-profit that promotes bluebirds and other native cavity nesters. Information about bluebirds, their nesting habits and how the monitoring program works is on the organization’s website. VBS is working to establish a statewide network of bluebird trails. Here’s what they learned by keeping count last year.
In 2013, 29 bluebirds and 19 tree swallows were born and fledged from the Frying Pan boxes. July’s hot weather seemed to discourage the birds, which may be why this total of 48 birds was down a bit from the two previous years (56 birds each in 2011 and 2012). The numbers fluctuate naturally, and the drop in 2013 is not a concern. It’s still a nice total, and it’s still fun to look for the bluebirds when you visit the park.
The number of bluebirds fledged in 2013 in monitored nests across Northern Virginia was up 2.2 percent from 2012. That’s 3,603 birds successfully raised from 56 monitored nests. In 2012, monitors logged 3,523 birds fledged on 49 trails, up from the 2,974 birds fledged on 47 trails reported in 2011 data. The numbers recorded by the monitors annually since 2000 are on the VBS web page.
Frying Pan is not alone among Fairfax County Park Authority sites hosting bluebirds. Burke Lake, Cub Run, Eakin, Ellanor C. Lawrence, Greendale, Lake Fairfax, Langley Fork, Laurel Hill, Nottoway, Oak Marr, Riverbend, and South Run are some of the Park Authority sites that host bluebird boxes. Another is Huntley Meadows (HMP), whose monitors track nesting box results in the park and at the adjacent Coast Guard Station (CGS). HMP has 27 boxes, 20 of which are paired to permit Eastern bluebirds and tree swallows to nest side by side, reducing competition within those species. Eastern bluebirds and tree swallows forage differently and do not compete for the same prey base.
Two paired boxes are located behind the observation tower on the south side of Huntley Meadows, and the others sit near the hike/bike trail on the northwest side of the park. The CGS hosts five boxes that overlook a well-kept lawn in contrast to the park boxes, which are located in open but typically overgrown meadows. All boxes are equipped with predator guards as prescribed by the Virginia Bluebird Society.
The VBS trains and organizes volunteers to monitor the nest boxes. If you are interested in becoming a monitor, contact VBS president Carmen Bishop. Many of the trails in Fairfax County are monitored by teams of four people, and there is a need for volunteers.
A reminder: it is important that people not open the boxes unless they are a trained monitor. Opening a box that holds nestlings age 13 days or older might cause them to fledge prematurely. Monitors keep records, so they know when and which boxes to avoid opening. The birds generally are pretty tolerant of monitor visits, but not endlessly so. Too much disturbance can discourage them from nesting. For visitors not part of the monitoring program, watch but don’t touch. Enjoy a walk along a bluebird trail, and enjoy the results of the monitors who are trying to keep Fairfax County blue.
Author Carmen Bishop is the president of the Virginia Bluebird Society and a former Fairfax County Park Authority employee. Co-author David Ochs is the Park Authority’s Manager of Stewardship Communications.