Eastern Bluebirds – by Jenn Stumer, Appalachian Creations, Inc.
Imagine our surprise when we found a pair of eastern bluebirds moving into the nest box our son Joey made. The house was installed about a month ago even though it was a little late in the season for bluebirds. We were still hopeful and thought it wouldn’t hurt to put it up. A family of wrens started moving in a short time later so we really gave up hope. Then about two weeks ago, my husband Joe sent me the picture above. The bluebirds found the nest box, kicked out the wrens and moved right in! Amazing! (Although I’m sure the wrens didn’t think so.)
Preferring open country, bluebirds were rare in Pennsylvania before the 1900s, when forests covered most of the state. They increased in number as forests were cut in the early 1900’s but declined sharply in the mid-1900’s because of the widespread use of pesticides and competition for nest sites from house sparrows and starlings. Today, bluebirds have made a significant comeback mainly because of landowners installing nest boxes.
Bluebird nest boxes are used to increase available nest sites and attract the bluebirds. They are easy to make or can be purchased at a local garden center or bird supply store. Once you have a nest box, mount it on a fence post or a 4X4 post that is at least 8 feet tall. (The first 2 feet should go into the ground.) The nest box is then mounted 4 to 6 feet above the ground. Be sure to choose a spot so that the box faces away from prevailing winds.
To attract migrating bluebirds, prepare nest boxes for use by February (this is why we thought we were too late.) Leave them up all year as some eastern bluebirds stay year-round. To ensure that they are weather-tight and clean, open the boxes after each nesting season and remove all nesting materials.
For the bluebirds that do migrate south in the winter, expect them to return in early March. The males will arrive first with the females arriving a short time later. The adults often return to the same territories where they previously lived, and the young from the previous year return to breed near the area where they were hatched.
When they arrive, the bluebirds look for suitable nesting sites. Pairs begin breeding in early April. Because of this most pairs will raise two broods in a season. The female lays three to six pale blue eggs, which she incubates. The eggs hatch within 2 weeks, and the babies are fed in the nest by both the male and the female for about 3 weeks. The adults then feed the young out of the nest for another 10 days before they are on their own.
Now for their diet…Insects, including grasshoppers, crickets, beetles, and caterpillars, make up 68% and the remaining 32% is fruit. They gather insects from leaves, branches, and the ground. They also catch insects in the air by hunting from perches, a technique known as “hawking.”
I think what helped fill our bluebird house so late in the season was the extended winter and spring we experienced. Without that I’m not sure we would have them in residence. The wrens would still be happily living in the nest box and we would be hoping for bluebirds again next year!