Bluebirds are found throughout North America including the Eastern, Western and Mountain Bluebirds. All bluebirds are cavity nesters and will use an artificial nest box. Habitat and nest cavities had been disappearing for many years, but bluebirds have made an incredible come back due to thousands of bluebird nest boxes being installed across the country.
.Nesting occurs from March through August. Only the female incubates the 4-6 eggs which she maintains at a temperature of 98 to 100ºF.
Bluebirds are generally monogamous, staying together throughout the breeding season, and may breed together for more than one season. However, some birds may switch mates during a breeding season to raise a second brood.
Bluebirds may raise two and sometimes three broods per season. Pairs may build their second nests on top of the first nest, or they may nest in an entirely new site. The male continues to take care of the recently fledged young while the female begins to re-nest. Young of the first brood will occasionally help raise their siblings in the second brood.
Both sexes defend territories; however, the males tend to defend territory edges while the females primarily defend the nest site.
Males may carry nest material to the nest, but they do not participate in the actual building. They spend much time guarding their mates during this time to prevent them from mating with other males.
Families flock together until fall, when they merge with other family flocks. Some, but not all, bluebirds residing in the northern portions of the range migrate to southern latitudes, but those residing in southern latitudes tend to be residential.
Adult Bluebirds tend to return to the same breeding territory year after year, but only a small percentage (three to five percent) of young birds return to where they hatched.
Bluebirds love mealworms and can be drawn in with a small dish filled with mealworms.
A bluebird can spot caterpillars and insects in tall grass at the remarkable distance of over 50 yards.
Bluebirds have no blue pigments in their feathers. Instead, each feather barb has a thin layer of cells that absorb all wavelengths of color except blue. Only the blue wavelength is reflected and scattered, resulting in their blue appearance to our eyes.
Eastern and Western Bluebirds sit on an elevated perch while searching for insects; when one is spotted, they drop to the ground to capture it with their bill. This sit-and-wait technique is called drop-hunting.
Bluebirds can fly at speeds up to 45 miles per hour if necessary.
.Nesting occurs from March through August. Only the female incubates the 4-6 eggs which she maintains at a temperature of 98 to 100ºF.