Bluebirds are a welcome sight in any yard, known for their striking color and gentle nature. Attracting these native songbirds requires providing their specific needs for food, shelter, and a secure environment. Unlike many common backyard birds, bluebirds are not typically drawn to seed feeders, necessitating a different strategy. Focusing on their unique dietary and nesting requirements creates a habitat that encourages them to stay and raise their young.
Providing Essential Food Sources
The bluebird’s diet is primarily insectivorous, meaning they rely heavily on insects and other arthropods. This is especially true during the breeding season when feeding their young. Approximately 68% of their annual diet consists of invertebrates, including caterpillars, grasshoppers, crickets, and beetles. Traditional seed feeders are largely ineffective for attracting them due to this reliance on insects.
The most effective supplemental food source is the mealworm, offered live or freeze-dried. Live mealworms are often preferred, but dried ones become more appealing when soaked in warm water for 10 to 15 minutes. Present mealworms in a specialized feeder with smooth sides or a tray feeder. This prevents them from crawling out and limits access by other birds.
Suet is another beneficial food, particularly during colder months when insects are scarce. Bluebirds are most attracted to insect-based suet, such as mealworm suet, or those containing peanut butter, fruit, or nut meats. These high-fat, high-protein options provide the energy needed to survive harsh weather.
Planting native berry-producing shrubs and trees offers a natural, long-term food supply, especially in the fall and winter. Species like flowering dogwood, sumac, winterberry, and eastern red cedar provide fruit that persists into the colder months. These native plants also provide shelter and perching spots, integrating the food source into the habitat.
Installing and Maintaining Nest Boxes
Bluebirds are secondary cavity nesters, relying on existing holes or man-made structures for nesting. Providing a properly designed nest box encourages them to settle in your yard. The entrance hole size is typically 1 1/2 inches in diameter for Eastern Bluebirds. This size is small enough to exclude larger, aggressive competitors like European Starlings.
Interior floor dimensions should be approximately 4 by 4 inches or 5 by 5 inches. The distance from the bottom of the entrance hole to the floor should measure 5 to 7 inches. Construct the box from untreated wood, such as cedar or pine, and include ventilation and drainage holes in the floor. A hinged side or front panel is necessary for regular monitoring and cleaning after each brood has fledged.
Mount the box on a smooth metal pole, not a tree, at a height of 5 to 7 feet off the ground. The location should be an open, grassy area with scattered trees nearby, as bluebirds prefer to hunt from low perches. Orient the entrance hole away from the prevailing wind and direct afternoon sun, often toward the east or southeast. This helps protect the nestlings from weather extremes.
Protecting the nest box from predators is necessary for successful nesting. A stovepipe or conical baffle installed on the mounting pole at least four feet off the ground is effective against climbing predators like raccoons, snakes, and squirrels. Managing aggressive competitors like House Sparrows is important, as they will displace or kill bluebirds. This may involve removing their nests immediately or using specialized slot entrances.
Creating a Safe and Welcoming Habitat
Beyond food and shelter, the overall environment must be safe and conducive to the bluebird’s foraging style. Bluebirds require a clean, shallow water source for drinking and bathing, which is important during hot weather. A bird bath with a depth of no more than three inches is suitable. Adding a dripper or mister can attract their attention with the sound of moving water.
Because bluebirds rely on insects for the majority of their diet, avoid using insecticides and pesticides in the yard. These chemicals eliminate the primary food source for adults and nestlings, making the habitat unsustainable. A pesticide-free lawn encourages a healthy population of the caterpillars, spiders, and other arthropods that bluebirds hunt.
General safety measures are important for protecting the birds from common threats. Keeping domestic cats indoors prevents a significant source of predation on adult bluebirds and fledglings. Ensure the area around the nest box is clear of dense shrubs or branches. This prevents predators from easily jumping onto the pole or hiding near the entrance.
Bluebirds are ground foragers, scanning for prey from low perches before swooping down to catch insects. Landscaping should include open, short-grass areas interspersed with low perches, such as fence posts or small trees. This supports their hunting behavior. The combination of open space for foraging and nearby cover creates a welcoming habitat.