Habitat use by Pileated Woodpeckers at two spatial scales in eastern Canada

To study the multiple spatial scale pattern of habitat use by Pileated Woodpeckers (Dryocopus pileatus L.), we compared the vegetation characteristics at used sites with those at unused sites at macrohabitat (154 ha radius plots) and microhabitat (ca. 0.04 ha radius plots) scales in the La Mauricie region of Quebec. Used macrohabitats were those in which woodpeckers were detected at playback stations. Used microhabitats corresponded to sites showing signs of foraging (i.e., excavated cavities). Pileated Woodpeckers responded to vegetation structure at both scales sampled. Macrohabitats used by woodpeckers had relatively low percentages of mixed shade-intolerant hardwood stands, coniferous stands, and stands of relatively low stem density and tree height, but included high percentages of 51- to 90-year-old stands. Microhabitats used by woodpeckers were characterized most strongly by a high density of large snags but also by a high density of small-diameter snags and a low density of shade-intolerant hardwood trees and coniferous trees less than or equal to 30 cm diameter at breast height. The concordance between the observed and predicted use of micro- and macro-habitat plots was independent of spatial scale (logistic regression, chi(0.05,1)(2) = 1.8, P = 0.18, n = 429), suggesting that habitats use by woodpeckers was influenced to a similar extent by habitat features measured at both spatial scales. Because Pileated Woodpeckers are likely to require specific habitat features at different spatial scales, forest-management guidelines intended to conserve this umbrella species should consider a multiple spatial scales approach.