The Eastern Bluebird populations have been decreasing. Factors contributing to the decline include loss of habitat and nesting sites through the clearing of land, removal of dead trees, and changing wooden fence posts for metal ones. Nesting site loss has been compounded by increasing numbers of two non-native species, the European starling and the House Sparrow. Both species are aggressive cavity nesters, can chase bluebirds away from nesting sites and even kill them.
Bluebird boxes can help
Man-made bluebird boxes are one of the best ways to help declining populations. It turns out that for bluebirds not any old birdhouse will do, no matter how cute it is on the outside. Just like us, they want a home that is safe and healthy. To do our part, Buncombe County Master Gardeners have placed three bluebird boxes in The Learning Garden on the grounds of the Buncombe County Extension office. The bluebirds moved in right away and have had multiple nesting cycles each year the boxes have been in place. Tree swallows and chickadees have also used the boxes, but with several boxes available the bluebirds always have a home.
Want to try your hand at making a bluebird box? The good news is that they are not hard to build. The North American Bluebird Society (NABS), North Carolina Bluebird Society (NCBS), and the Audubon Society all provide excellent plans and instructions regarding construction and placement.
Prefer to buy one? State Employee Credit Union offices in our area offer $10 boxes made by the Eastern Bluebird Rescue Group, a volunteer organization based in Warrenton, NC. .
Placing the bluebird box
Bluebirds prefer an open area with trees and shrubs in proximity for fledglings to reach easily when they are testing their wings. Mount the box using a smooth round pipe which acts as a deterrent for predators like possums, racoons and snakes. Consider adding a predator guard to the pipe for added protection.
Your bluebird boxes may not be used right away, but keep checking. Bluebirds usually return to the same boxes every year. They can have up to three nesting cycles a season starting in March and continuing through August.
Bluebird Monitoring Activities
|March||Males choose mates and nesting sites|
|April-May||First nesting cycle|
|June-July||Second nesting cycle|
|August||Third nesting cycle|
After mating season, bluebirds leave their boxes and flock together. Bluebirds of North Carolina do not migrate. Bluebirds will roost in pine trees and nesting cavities during winter, sometimes even in the bluebird boxes.
If possible, keep records of your findings when monitoring your boxes. Your information is important to NABS and Cornell Ornithology Lab, both of which compile data on bluebirds. You will find a form on the NABS website for collecting and reporting this data.
Written by Mary Ann Snedeker, Buncombe County Extension Master Gardener