My kids just called me to share interesting facts about bluebirds they just learned. Since we started homeschooling in 2018, my kids have the ability to learn at their own rate, on things in the world around them, not useless facts and figures. And learning about attracting bluebirds is one of those things. There are 3 species of bluebirds in the world, all native to North America. We have just one of those in the Central Great Plains, the Eastern Bluebird. When we put our focus on attracting just one native bird, it enhances the landscape for all native birds.
Bluebirds, like all native birds are protected under the Migratory Bird Treaty Act of 1918. The Migratory Bird Treaty Act (MBTA) prohibits the take (including killing, capturing, selling, trading, and transport) of protected migratory bird species without prior authorization by the Department of Interior U.S. Fish and Wildlife Service. Because of the act, we have protections on all of our native songbirds and others, which helps homeowners in attracting them.
Like other birds, bluebirds need food, shelter, water, and protection. How we can help them get those things is up to us. It all starts in our own yards.
Nesting for Bluebirds
We will start with shelter, or nesting. Bluebirds begin the nesting process in early spring. In our region, males begin looking for homes in late February and mates by early March. Therefore, if we are supplying homes for them, we need to have them out and ready by mid-February. Bluebirds are cavity nesters, meaning they will use cavities created by woodpeckers in snags (what are snags?), hollows in trees, or nest boxes. Because of our man-made nest boxes, bluebirds have come back from decline to nearly 23 million birds in 2022.
They prefer to have their homes in open areas such as meadows, pastures, or fields, especially those with lower grasses. They hunt the majority of their food from grasslands. If you are providing nesting boxes, place them 100 feet from a tree or perch for the fledglings, and 300 feet apart from each other. They should be placed 5 feet above the ground, on a secure post or tree, facing a tree or away from prevailing winds (southwest and northwest in Kansas).
Nest Boxes
Nest boxes should be no more than 6 inches square in the inside, and made from a durable material such as cedar wood. They can be painted on the outside with latex paints. However, there are some studies which show that PVC nest boxes deter House Sparrows, the bluebird’s main antagonist. But many children, such as my own, prefer to make wooden boxes, both for the birds and to show at the county fair.
Next boxes for bluebirds should be well ventilated, but waterproofed as much as possible. There is some debate about the hole sizes. But it seems that the best course for bluebirds is to do a slit opening at the top, rather than a round hole. This slit helps deter sparrows as well as the material does. But if you are determined to do a circular hole, make it no bigger than 1.5 inches in diameter.
Boxes should be mounted 50 to 200 feet away from woodlands or brushy areas, because wrens and other birds which prefer brush will also use the boxes.
Food for Bluebirds
What do they eat? Native insects and berries comprise the diets of most songbird species. For the bluebird, it varies from season to season. During the nesting and breeding season, they hunt and eat crickets, grasshoppers, caterpillars, worms, moths, and other insects, mainly from the ground or low plants. How can you help them find food? First of all, STOP USING PESTICIDES. Pesticides such as insecticides in your yard and garden reduce the numbers of insects that can be consumed by birds. By turning your yard over to biodiversity and natural processes, you will invite more and more birds.
Around the landscape you should start by planting as many native species into meadow garden, flower beds, and borders as possible. Starting with keystone species, you can add a great amount of biodiversity to the landscape.
During the winter months, bluebirds, which do migrate, eat mainly berries from trees and shrubs. Plants that you can add for keeping bluebirds in your landscape include:
- Juniper
- Arrowwood viburnum
- Winterberry holly
- American holly
- Blackhaw viburnum
- Smooth sumac
- Black chokeberry
- Red chokeberry
- Coralberry
You can also provide a flat-topped feeder with mealworms and suet cakes for them during the winter feeding time. Do not use poor quality bird-food mixes which contain high amounts of millet, milo, or other fillers.
Providing Water
During the summer months I am covered by the 2 lakes, 1 pond, 1 river, and 1 supply stream which are all within 800 feet of my backyard. But what about those who are not, or winter? If you do not have a major source of water available within close proximity to your garden, then you may want to add it. Bluebirds prefer moving water during the summer months, so adding a bubbler or pondless waterfall may be the best idea. Even animal waterers such as large tanks or small duck ponds may be enough, as long as its fresh and somewhat moving.
Through the winter, provide heated water in a dog bowl or bird bath for all the birds visiting, because those bigger bodies of water may be iced over. A heated dog waterer for outside is probably the best bet. Put it high enough off the ground that cats and other predators cannot sneak up too quickly.
The Breeding Season
Bluebirds can have 1 to 4 clutches or broods of babies each season, depending on food and water resources. If there is a lot of food available, then they will have more broods. The male courts a female by dancing and waving his wings at her. If she chooses him, then they mate, and the female prepares the nest in the chosen location. Nests are cup shaped and made from grasses and pine needles. If you are checking your nest boxes weekly, and see a nest which has a lot of weeds or trash in it, then the box has likely been invaded by a house sparrow, which you should remove.
After the nest is made the female will lay 2 to 7 small, pale blue eggs. During this time, the male is absent, likely watching but not protecting the brood. After the eggs hatch, 13 to 17 days later, the male returns and both parents begin feeding and managing the brood. Approximately 14 to 17 days after hatching the chicks will begin to fledge, or fly for the first time. During this growing period, it may take as many as 2000 insects (mainly caterpillars) per day to raise the brood.
What Else Can I do for Bluebirds?
Start by keeping an eye on them and the nest boxes. Check the boxes weekly during the nesting season to make sure there are no invaders, such as the house swallows. If you find house swallows, you can kill or trap them (invasive birds are not protected). I knew about the problem with house sparrows, but never thought about checking the boxes weekly before now.
Join the North American Bluebird Society or any local bird groups or societies. Some of our local societies are Audubon of Kansas, Kansas Native Plant Society, Nebraska Statewide Arboretum, The Nature Conservancy, and the Grassland Heritage Foundation. I am sure there are more local bird watching groups in each city or region.
Rewilding your yard with native plants is the best overall choice after providing food, water, and shelter. To do this, you need to take inventory of what you already have and determine what you need to add. If you need help with this step, please call Grimm’s Gardens and ask for Andrew (me). I would be happy to help as much as possible. We do consultations for $100/hour plus travel within 100 miles of our main office in Hiawatha, KS.
Conclusion
Bluebirds are easily recognizable and one of the most popular of our native songbirds. Once you start attracting them to your garden by changing the landscape, yu will enhance it for other birds to show up too. Continue to keep up the good work.
Happy planting!
