The Pileated Woodpecker as a Keystone Habitat Modifier in the Pacific Northwest

We propose that the pileated woodpecker (Dryocopus pileatus) is a keystone habitat modifier in the Pacific Northwest. It is the largest woodpecker in this region and the only species that forages primarily by excavating; only pileateds are capable of creating large cavities in hard snags and decadent live trees. A wide array of species, including many that are of management concern in the Pacific Northwest, use old pileated nest and roost cavities. In addition, pileateds provide foraging opportunities for other species, accelerate decay processes and nutrient cycling, and may facilitate inoculation by heart-rot fungi and mediate insect outbreaks. Because of the potential keystone role of pileated woodpeckers in Pacific Northwest forests, it may be appropriate to give special attention to their habitat needs in forest management plans and monitoring activities.