Tips to Help Bluebirds and Other Cavity Nesters

Are You Ready?

It’s spring and birds are thinking of one main thing: it’s time to raise a family. You can lend them a hand to help! But before you run out and build or buy a nestbox, there are a few things for you to examine.

First, look around your own backyard. What is the habitat? Do you know where to place a nestbox and how to make it safe for the guests? What is the level of activity? Are neighbors’ cats running loose and spending time in your yard and around your feeders? Before you put up a nestbox it is important to be responsible and do some homework. Remember, by putting up that nestbox you are accepting responsibility to the birds you hope to attract. You want those birds to be successful! So do some research online or pick up a book to learn more before you start.

Which Species?

In Ohio, there are several species of secondary cavity nesting birds that you can hope to attract to your yard. (A secondary cavity nesting species is one that cannot excavate its own nesting site, but instead relies on holes excavated by woodpeckers — or relies on the handiwork of humans to build a safe home.) Each of these birds has specific habitat requirements and in some cases there is overlap and conflict when housing is at a premium. You have heard the phrase “location, location, location” when looking for a home. The birds are looking for the right “habitat, habitat, habitat.”

In central Ohio, we can attract Eastern Bluebirds, Tree Swallows, Tufted Titmice, Carolina Chickadees, Carolina Wrens and House Wrens to our man made nestboxes. And the ever-present, non-native House Sparrow is always trying to capture a good home from one of our protected native species.

Bluebirds

Let’s start with the bluebird. In central Ohio they are starting to nest in April. However, they will nest two to three times a season given the right nesting conditions. They prefer an open grassy space, short grass, and perches (which may include trees, posts or garden stakes) to find their favorite food of spiders and ants to caterpillars to larger crawling, hopping and sometimes some flying insects. Try to place the nestbox 40 yards from a wood edge or structure and certainly away from a seed feeding station. Bluebirds will also eat fruit and berries, so consider offering some bird friendly plantings in your yard. Offer water if it is not readily available.

Inspect your nestbox to see that you can open it for monitoring and cleaning and that it is ventilated and has good drainage. Make sure the inside of the door has grooves so the young can climb out for their maiden flight. Face the nestbox in a southeastern direction out of the prevailing northwest winds and weather. Place a baffle on the pole (do not place the nestbox on a tree) to discourage climbing predators such as raccoons, snakes and feral cats.

Bluebirds build a nest of dried grass or pine needles in a week or less. They skillfully construct a level nest with a nice cup where they lay an egg a day (4-6 in a clutch), then begin incubation after the last egg is laid. Take the time to keep a notebook of your observations and be sure to monitor or open the nestbox weekly. The female will incubate the eggs for 14 days, and the eggs all will hatch on the same day. Try not to disturb the female during hatching. It could be harmful to the young if they become chilled or damp because you opened the box during cool, wet weather. Use a mechanic’s mirror and flashlight instead of opening the box. By watching the behavior of the adults you will be able to see them flying to the nestbox with food and leaving with whitish fecal sacs in their beaks. This is a good sign of a growing family! The parents can feed the young 30 to 50 times a day. Offering mealworms can help the adults and later the young and can be a fun thing to do in your yard.

As the young grow older, be careful to keep good notes and do not open the nextbox after the young are 12 days old. Opening the nestbox after the 12th day can cause the young to prematurely fledge, or leave the box too early, and lessen their chance to survive. As it is, only 50% make it to their first birthday. The young fledge or leave the nestbox between 18-22 days of age. The adults, primarily the male, will carefully watch over the young after fledging and will teach them to fly and hunt for their own food. By about 2.5 weeks after fledging the young will begin to hunt on their own. Soon the female will start another nest preparing to raise another family.

Bluebird Resources

Pick up the most widely read book by Julie Zickefoose “Enjoying Bluebirds More”. Visit the websites of Bird Watchers Digest, Cornell and the Birdhouse Network site http://www.birds.cornell.edu/birdhouse and the North American Bluebird Society to obtain more useful information.

Other Species

Some other species may move into a nestbox, depending on the habitat.

Tree Swallows are neo-tropical migrants and delightful aerial insect eaters who prefer to be somewhat close to water. They line their dried grass nests with curved feathers, and it’s fun in the spring to toss curved duck or chicken feathers near water where the birds are swooping to feed. The Tree Swallows will take these feathers, fly about doing their courtship acrobatics, then pop into the nestbox to place the feather in the dried coarse grass cup to provide for some warmth and camouflage where the female will lay her eggs. Tree Swallows will have a clutch of about 7 eggs and sometimes raise two families. They return late March to early April…and how exciting to see them back!

House Wrens also are neo-tropical migrants and are called the “boss-of-the-brush.” They land and eat insects while they scold us from the shrub and brush habitats they prefer. While they are delightful little sprite songsters, they are territorial in nature and check out any cavity near their shrub habitat, sometimes evicting other bird species. Their willingness to nest close to people in small gourds or small wren boxes up close to our windows make them a popular bird to attract and enjoy.

Chickadees and Titmice, year round residents and cousins, prefer a woods or wood edge to build a nest. The nest of the chickadee is a large moss nest; that of the titmice is a mixture of moss and dried leaves and grass. Both species can hiss at you when you monitor their nests.

Some Final Advice

This is just a sampling of some of our backyard favorites. Keep in mind that these birds are protected under the Migratory Bird Act, so no one should be harming them. Providing food, water, cover and housing is a rewarding experience for the whole family. You will learn together, feel like you are really lending a hand to whomever moves in to your backyard housing. You also will want to share your experiences with others.

It’s important to eliminate the use of pesticides and to try to garden with native plants for the benefit and well-being of your guests. Birding is the number two hobby in the country, second only to gardening, so you won’t be alone.

Keep a field guide handy, binoculars, journal and good resources to help you. The rewards are endless and your contributions to conservation important. Spread the word to your friends and neighbors so they can join in on the fun. The sharing of family time is priceless.

Henry David Thoreau said, “If the warble of the first bluebird does not thrill you, know that the morning and spring of your life are past…His soft warble melts in the ear as the snow is melting in the valley’s around. He wears the sky on his back.” Maybe Mr. Bluebird will Zippety Doo Dah just for you!! Good luck.

Scroll to Top