About Leuconotopicus villosus (Linnaeus, 1766)
This species, Leuconotopicus villosus, more commonly known as the hairy woodpecker, can be described by the following physical traits. Adult hairy woodpeckers have mostly black upper parts and wings, paired with a white or pale back and white spotting on the wings. The color of their throat and belly ranges from white to sooty brown, and this variation is tied to the bird's subspecies. Each side of the eye has one white bar, one above the eye and one below. The tail is black, with white outer feathers. Adult males have a red patch, or two adjacent red patches, on the back of the head, while juvenile males have red, or more rarely orange-red, coloration on the crown. The hairy woodpecker measures 18–26 cm (7.1–10.2 in) in total length, has a wingspan of 33–43 cm (13–17 in), and weighs between 40–95 g (1.4–3.4 oz). The hairy woodpecker has almost identical plumage to the smaller downy woodpecker. Aside from differences in size and voice, the most reliable field identification trait is that the downy woodpecker has a shorter bill relative to its head size. Another identifying difference is that the hairy woodpecker's white tail feathers lack spots, while the downy woodpecker's white tail feathers have spots. Despite this outward similarity, the two species are not closely related, and they are generally placed in separate genera. This close similarity in appearance is a prominent example of convergent evolution. Only tentative hypotheses exist for why this convergence occurred, and considerable size difference between the two species means ecological competition between them is minimal. The hairy woodpecker's distribution covers mature deciduous forests across the Bahamas, Canada, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Saint Pierre and Miquelon, and the United States. It occurs as a vagrant in Puerto Rico and the Turks and Caicos Islands. Most hairy woodpecker populations are permanent residents, though individuals from the extreme northern part of the range may migrate further south for winter, and birds living in mountainous areas may move to lower elevations in colder seasons. Mating pairs excavate tree cavities to nest, and lay an average of four white eggs per clutch. Foraging by hairy woodpeckers takes place on trees; they often turn over bark or excavate wood to uncover insect prey. Their diet consists mainly of insects, but they also consume fruits, berries, nuts, and occasionally tree sap. They are known predators of the European corn borer, a moth species that causes over $1 billion in annual costs to United States agriculture, from both crop losses and population control efforts.
