Often seen sitting on fences and branches near fields and lawns, the Eastern Bluebird is a farm favorite. Brightly colored males and elegant greyish females are quick to take advantage of nesting boxes mounted to abandoned fence posts and trees. It is the male who first finds a nesting site. While he works to attract a discerning female to the nest with his striking orange chest plumage and symbolic offerings of twigs and leaves, he must also aggressively protect it from other birds. If he manages to charm a mate with his display, the female will then complete the nest and lay two to seven pale blue eggs. The eggs – 20% of which may have been fertilized by alternative male partners – will hatch 11-19 days later. Their bond often lasts several seasons and commonly produces more than one brood a year. Hatchlings from spring broods leave their parents in mid-summer; broods raised later in the year may travel with their parents throughout the winter.
Typically feeding on insects during the spring and summer, the Eastern Bluebird is a savvy hunter who pounces on unsuspecting prey from above. Their remarkably keen eyesight – they are capable of seeing their quarry from 60 feet away – helps them to track down the beetles, caterpillars, spiders, and grasshoppers they prefer. Bluebirds relay on berries and other fruits during the colder months when insects are not as prevalent.
With an estimated global population of 22 million, bluebirds are thankfully very common. However, even with their large numbers and low conservation threat, their cheerful demeanor and insectivorous diet makes installing nesting boxes well worth the effort.