Diet and food availability: implications for foraging and dispersal of Prince of Wales northern flying squirrels across managed landscapes

• Published in: Journal of Mammalogy
• Main Authors: Flaherty, Elizabeth A., Ben-David, Merav, Smith, Winston P.
• Format: Text
• Language: English
• Published: Oxford University Press 2010
• Subjects: Feature Articles; Prince of Wales Island; Alaska
• Online Access: http://jmammal.oxfordjournals.org/cgi/content/short/91/1/79; https://doi.org/10.1644/09-MAMM-A-014R.1

Where dispersal is energetically expensive, feeding and food availability can influence dispersal success. The endemic Prince of Wales northern flying squirrel ( Glaucomys sabrinus griseifrons ) inhabits a landscape mosaic of old-growth, 2nd-growth, and clear-cut stands, with the latter 2 representing energetically expensive habitats. We estimated the diet of flying squirrels using stable isotope and fecal analyses, determined whether food availability varies among forest stands, and assessed the likelihood of foraging across a managed landscape given the distribution of foods on Prince of Wales Island (POW), Alaska. Both stable isotope and fecal analyses revealed that conifer seeds, lichens, and fungi were the main dietary items consumed and assimilated by flying squirrels. Similarly, soil macroinvertebrates were consumed by squirrels, whereas berries were not. Nonetheless, although examination of stable isotope data suggested that squirrels assimilated few nutrients from truffles, this food source was among the most frequent diet items in feces, probably because flying squirrels assimilate elements other than nitrogen from fungi. Our surveys showed that conifer seeds, truffles, and lichens were more prevalent in old-growth than 2nd-growth and clear-cut habitats. Thus, our results indicate that diet and availability of food items on POW may influence foraging success and dispersal movements of G. sabrinus across fragmented landscapes because of limited availability of food resources in the managed habitats.