Eastern Bluebirds are a common songbird across North America. Their diet is diverse and adapts to the changing seasons, though it primarily centers on insects. Understanding their dietary habits helps in observing these birds and supporting their well-being, and appreciating their ecological role.
Insect-Based Diet
Eastern Bluebirds rely on insects and other invertebrates as a main food source. During the breeding season, particularly in spring and summer, protein-rich arthropods form up to two-thirds of an adult bluebird’s diet. This high-protein intake is important for feeding their young. They consume a variety of insects, including grasshoppers, crickets, beetles, butterflies and moth larvae, and spiders. Earthworms and snails are also part of their diet. Bluebirds control insect populations, often preying on garden pests.
They primarily find prey by scanning the ground from a low perch, dropping from vantage points to snatch insects. Ground foraging is their main method.
Seasonal Fruit and Berry Consumption
The diet of Eastern Bluebirds changes with the seasons. During late fall and winter, their diet shifts to primarily include fruits and berries. This seasonal adaptation provides essential energy and nutrients when insects are scarce.
They consume a variety of wild fruits and berries, such as wild grapes, sumac, holly, dogwood, eastern red cedar, juniper, honeysuckle, hackberry, pokeberries, blackberries, and raspberries. These plant-based foods help them survive during periods of limited insect availability.
Hunting and Foraging Techniques
Their most characteristic method is the “perch and pounce” or “drop-hunting” technique. This involves perching on an elevated spot, like a fence post or low tree branch, and intently scanning the ground below. They possess keen eyesight, spotting insects from up to 60 feet away.
Once prey is sighted, they swiftly drop to the ground to capture it. This ground-based foraging accounts for most of their hunting attempts. Bluebirds may also engage in aerial hawking, catching insects mid-flight, or glean them from plant leaves. Larger prey items with hard exteriors may be beaten against a hard surface before being eaten.
Attracting Bluebirds with Food
To attract Eastern Bluebirds, offer supplemental food sources. Mealworms, both live and dried, are a preferred food and can be offered in platform or tray feeders. Live mealworms are especially attractive. Suet, especially varieties infused with berries or insects, can also be offered during colder months for a high-calorie treat.
Planting native berry-producing trees and shrubs, such as dogwood, sumac, wild grape, and juniper, provides a natural food source. Avoid feeding bluebirds items like bread, large seeds, or processed foods, as these lack proper nutrition and can attract undesirable species. During the breeding season, crushed, roasted eggshells can provide calcium for nesting females. Avoid using pesticides, as they eliminate the bluebirds’ natural insect food sources.