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• 1. [Article] Granary-Site Selection by Acorn Woodpeckers in the Willamette Valley,

  © 2006 by the Northwest Scientific Association

  Citation × Citation Citation Abstract Copy Title: Granary-Site Selection by Acorn Woodpeckers in the Willamette Valley, Author: Rosenberg, Daniel K., Johnson, Eric M. © 2006 by the Northwest Scientific Association Title: Granary-Site Selection by Acorn Woodpeckers in the Willamette Valley, Author: Rosenberg, Daniel K., Johnson, Eric M. © 2006 by the Northwest Scientific Association Close

• 2. [Article] Granary-site selection by acorn woodpeckers in Benton County, Oregon

  The acorn woodpecker (Melanerpes formicivorus) is among the most common primary cavity nesters of the Oregon white oak (Quercus garryana) woodlands. Understanding their selection of granary sites is important ...

  Citation × Citation Citation Abstract Copy Title: Granary-site selection by acorn woodpeckers in Benton County, Oregon Author: Johnson, Eric M. The acorn woodpecker (Melanerpes formicivorus) is among the most common primary cavity nesters of the Oregon white oak (Quercus garryana) woodlands. Understanding their selection of granary sites is important in evaluating habitat quality and management actions. I hypothesized that granary locations would be consistent with the optimal foraging theory. Site characters were selected that were hypothesized to affect granary profitability. I compared site characteristics of granaries and non-granaries within the home ranges of 20 colonies in Benton County, Oregon during the winter of 2001. Granaries had greater oak basal area (x*=104 ± 16 dm2), shorter brush height (x*=-26 ± 7 cm), larger diameter at breast height (dbh) (x*=l1 ± 4 cm). Of 14 a priori models considered, I determined that the Forage Model was the best predictor of granary presence. This model is based solely on the oak basal area variable, a measure of potential acorn production. Increased acorn production in the vicinity of granaries is likely beneficial to the birds because minimal effort is expended in caching maximum forage. Title: Granary-site selection by acorn woodpeckers in Benton County, Oregon Author: Johnson, Eric M. The acorn woodpecker (Melanerpes formicivorus) is among the most common primary cavity nesters of the Oregon white oak (Quercus garryana) woodlands. Understanding their selection of granary sites is important in evaluating habitat quality and management actions. I hypothesized that granary locations would be consistent with the optimal foraging theory. Site characters were selected that were hypothesized to affect granary profitability. I compared site characteristics of granaries and non-granaries within the home ranges of 20 colonies in Benton County, Oregon during the winter of 2001. Granaries had greater oak basal area (x*=104 ± 16 dm2), shorter brush height (x*=-26 ± 7 cm), larger diameter at breast height (dbh) (x*=l1 ± 4 cm). Of 14 a priori models considered, I determined that the Forage Model was the best predictor of granary presence. This model is based solely on the oak basal area variable, a measure of potential acorn production. Increased acorn production in the vicinity of granaries is likely beneficial to the birds because minimal effort is expended in caching maximum forage. Close