The Outside Story: Spring excavations: pileated woodpeckers

By Susan Shea

Wuk-wuk-wuk-wuk! With a rattling call, a large bird took off from a tree and flew in an undulating fashion across our field towards the woods. It was black and the size of a crow, but flashes of white on the underside of its wings and a red crest on its head easily identified it as a pileated woodpecker.

We had seen the unmistakable signs of pileateds foraging for insects in the adjacent woodland:  huge rectangular holes excavated in trees with big wood chips littering the ground below, long strips of bark pulled off a dead elm, a rotten log torn apart. We had heard their loud drumming echoing through the forest. There was likely a nest nearby, although we never found it. The pileated woodpecker, up to 19 inches long with a wingspan up to 30 inches, is North America’s largest woodpecker. (The ivory-billed, of southeastern swamps and Cuba, was larger, but that species is believed to be extinct.) Pileated means “crested”; years ago, the bird was often called a log-cock.

In early spring these woodpeckers engage in a courtship dance which involves bowing, spreading wings, swinging heads, and raising crests. The male can be distinguished from the female by a red mustache extending backwards from the base of his bill. Both members of the pair excavate a nesting hole, usually in a dead tree, but sometimes in a live tree with heartwood decay, or even in a utility pole. The nest site is often near water.

Pileateds prefer large-diameter trees for nesting. Mature forests support higher populations of the birds because the bigger trees, increased canopy cover, logs, and stumps provide enough food for smaller territories.

Nest holes are excavated in April or May over a period of a few weeks. The entrance to the pileated’s nest is round or triangular, in contrast to the rectangular holes they make while feeding. To deter parasites, a new hole is chiseled out every year, sometimes in the same tree. The female lays three to eight glossy white eggs on a bed of fine wood splinters. Both sexes share incubation duties.

After 18 days, the young woodpeckers hatch. The parents make frequent trips to the nest, inserting their beaks into the nestlings’ throats and regurgitating ants, beetles, caterpillars, and other insects. The young grow rapidly on this diet, opening their eyes at eight days and developing feathers. When a parent appears, they crowd the hole, eagerly stretching out their heads and crying for food. The male broods the young overnight while the female sleeps in one of several roosting holes drilled nearby.

Parents are normally secretive around the nest and will defend their young vigorously. However, Vermont naturalist and author Ted Levin was able to observe two different nests of pileateds by slowly acclimating them to his presence. He began by hiding in a blind, progressed to a ladder, and was able to get within five feet of the nest hole to photograph the birds.

At about four weeks of age, the young woodpeckers leave the nest and begin to learn how to find food. Levin watched pileated parents open anthills in the ground for their young. With their powerful bills, these woodpeckers chisel holes in dying trees and extract carpenter ants and wood-boring beetles from tunnels with their barbed tongues and sticky saliva. They also eat flies, moths, grubs, acorns, beechnuts, wild grapes, and cherries. Pileateds occasionally come to bird feeders for suet and nuts.

Fledglings stay with their parents into the fall. Often the parents remain together and defend their territory until the next nesting season.

The pileated’s old roosting and nesting cavities are used by many other animals, including owls, wood ducks, flying squirrels, bats, fishers, and martens. Their role in creating shelter for other animals make the pileated woodpecker an important part of the forest ecosystem. This keystone species has gradually resurged in population as our forests have recovered from the widespread clearing of the eighteenth and nineteenth centuries.

They are also spectacular birds. One hundred years ago naturalist Ernest Waters Vickers described a male pileated woodpecker drumming:  “With such energy did he hammer that his whole body shook and his wings quivered. He fairly hurled himself wildly at it. The great loose hair-like scarlet crest flowed in the sun and his scarlet moustache added to his noble and savage appearance.”

Susan Shea is a naturalist, freelance writer, and conservation consultant who lives in Brookfield, Vt. The illustration for this column was drawn by Adelaide Tyrol. The Outside Story is assigned and edited by Northern Woodlands magazine, and sponsored by the Wellborn Ecology Fund of New Hampshire Charitable Foundation.