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WSU/Pend Oreille Extension introduced the Sense of Place series in 1999, with a focus on place-based stewardship education. Since 2001, a partnership with the Kalispel Tribe of Indians Natural Resources Department (KNRD) has supported this newsletter and allowed us to expand class offerings through EPA funding. Further staff support comes through Renewable Resources Extension Act (RREA). Many thanks to our partners and to you, our readers, for your continued enthusiasm for "digging" into the natural history and culture of this part of the world.

Keystone Carpenters

by Paul Bannick

Winding between mature trees like a giant red-combed black arrow, the Pileated woodpecker arrives like a forest hero, entirely appropriate for one of North America's most important keystone species.

A keystone species is one that alters its habitat for the benefit of other species and thus has an inordinate impact upon its habitat. The pileated woopecker earns the keystone tag for the many ways it improves its environment for a variety of forest creatures including insects, amphibians, birds and mammals.

The pileated is North America's largest surviving woodpecker at 19 inches in body length. Although the pileated is described as “crow size,” to me it seems a bit larger and certainly more striking. The adjective pileated means “crested,” and both sexes sport a brilliant red crest, although on the larger male the red extends forward to the bill. A red malar or mustache also adorns the male, forming a narrow stripe that runs back from the base of the bill, merging into a black stripe that both sexes have on the sides of their necks. The large, chisel-like bill of this woodpecker enables it to craft impressive excavations.

Thick, standing trees featuring large oval cavities, littered at the base with wood-chips and pocked with fist-sized rectangular excavations at waist level and huge oval cavity entrances high above are sure signs of this great bird's presence.

Pileated woodpeckers mate for life, and if a partner dies the surviving bird will defend its territory alone and try to recruit a new mate from a neighboring territory. New vertical oval-shaped nest cavities are excavated every year, with several partial cavities often created before a commitment is made to the final one. Cavities are defended, but these birds allow other cavity-nesting birds to nest in the same tree. Once the young fledge, the adults dig additional cavities in which the young woodpeckers explore and roost. Each adult bird creates several roost cavities to use at night and during bad weather. These cavities are often created in hollow trees or snags so that only the entrances require excavation. Usually Pileateds create several entrances to provide escape routes in case a predator enters.

These birds also excavate large feeding cavities as a byproduct of their pursuit of wood-boring insects and insect larvae, frequently close to the ground. All these cavities and excavations tend to be chiseled as rectangular, horizontal shafts straight into stumps and snags. They require large old trees and leave behind potential nests and habitat improvements for dozens of species. Although they often excavate in decayed wood, they are the only western woodpeckers that also excavate in heartwood, the denser core of the tree. They are probably responsible for infecting a significant percentage of trees throughout their range with heart rot, a disease that weakens the heartwood, thereby creating a suitable base for weaker excavators such as sapsuckers, creepers, chickadees, wrens, and nuthatches.

The pileated will go to extreme lengths to pursue carpenter ants and other forests pests, ripping apart trees, excavating in snags until they topple, and prying off large sections of bark to gain access to the honeycombed nests. Other insect-eating birds, including other woodpeckers, take advantage of these excavations and sometimes trail the pileated in hopes of snagging missed treats. The pileated also eats wood-boring beetle larvae, fruit, berries, and even suet from feeders.

Beyond creating nest cavities, pileated woodpeckers aid in the forest decomposition process by breaking down trees into smaller, more easily decomposed pieces and creating dozens of huge nesting, roosting, and feeding cavities each year that serve the needs of several animals too large to use cavi- ties created by smaller woodpeckers. These wood chips and chunks also help return nutrients to the soil for plants and return soil moisture for amphibians.

The pileated woodpecker creates cavities twice the size of those provided by the northern flicker. In the Pacific Northwest alone, more than twenty species of secondary cavity nesters use these cavities. Large cavity nesters such as the wood duck, common goldeneye, bufflehead, hooded merganser, and northern hawk owl, are too large to use cavities created by any other woodpecker. Some of the more sensitive species benefitting from these cavities include several old-growth dependent “species of concern,” such as the Pacific fisher, American marten, silver-haired bat, and common merganser, as well as Vaux’s swift, which is on the “sensitive species” lists of both Washington and Oregon.

Although this bird emits several vocalizations, its territorial call is its most famous. It sounds a bit like a northern flicker but much louder and wilder and is used as the background call in jungle scenes of many old movies. This call is phoneticized as cuk, cuk, cuk. Its drumming is loud and slow like a drumroll that speeds up and becomes softer toward the finish.

The most dense populations of pileated woodpeckers are established in old-growth forests with an abundance of large, old trees in various states of decay. If such trees remain in other habitats, such as younger woodlands or even large parks, pileateds can nest in them as well. These woodpeckers can be found in forested lands in much of the western and eastern United States and southern Canada.

Timber harvest can greatly reduce populations. Pileated woodpeckers were nearly depleted in the eastern United States in the early 1900s after the land was cleared, but they rebounded after forests grew back. Populations throughout much of their range are stable now, but conversion of old-growth forests to younger or single-age stands, removal of large nest snags, and fragmentation of habitat are.

Pileated woodpeckers are currently candidates for endangered species listing by the Washington Department of Fish and Wildlife and are considered a “Species-at-Risk.” Population declines of pileateds could precipitate the decline of many species of wildlife that depend upon their excavations for shelter and food.

The U.S. Forest Service has identified the pileated woodpecker as a "management indicator species" (MIS) of mature forest habitats. Indicator species are ones which rely upon critical elements of habitat so that abundance or scarcity indicate the ecological health of habitat and its ability to meet the needs of other species dependent upon the habitat. In the Colville National Forest this translates to old-growth Douglas Fir and Cedar/Hemlock forests containing abundant snags and large downed logs. In order to maintain their habitat the Colville Forest plan designated such stands as pileated woodpecker units.

In addition to the protections afforded pileated woodpeckers within these units, regional groups including Conservation Northwest (http://conservationnw.org) and Northeast Washington Forestry Coalition (http://www.newforestrycoalition.org) are advocating for quantifiable benchmarks to protect current old-growth habitat wherever it exists across the Colville National Forest, as well as for restoration management that will improve and expand Pileated Woodpecker habitat. This approach will benefit the many wildlife species requiring the robust presence of these keystone birds, as well as the people who appreciate them.

Note: Photographer and naturalist Paul Bannick is the author of the 2009 book The Owl and the Woodpecker: Encounters with North America's Most Iconic Birds. Paul will be making a presentation in Colville on March 26th for the Friends of the Little Pend Oreille Wildlife Refuge, and will serve as the keynote speaker for the SandHill Crane Festival in Othello Washington on March 27th. You can find more details at www.paulbannick.com

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