Food habits of the northern flying squirrel (Glaucomys sabrinus) in Oregon

Abstract

Digestive tracts of 91 northern flying squirrels (Glaucomys sabrinus) were analyzed for food items; 28 were from northwestern Oregon and 63 from northeastern Oregon. Ninety percent or more of the ingested materials were fungi and lichens, including 20 genera of hypogeous fungi. The northern flying squirrel, in using hypogeous fungi as a major food source, is an important nocturnal disperser of the spores. In Oregon coniferous forests, these fungi are obligatory ectomycorrhizal symbionts with the trees in which the squirrels live.

Lichen bioindication of biodiversity, air quality, and climate: baseline results from monitoring in Washington, Oregon, and California.

“…Lichens play many essential functional roles in these forested ecosystems. For instance, species of Bryoria and Alectoria are important forage for elk, caribou, deer, and flying squirrels (Maser et al 1985, McCune 1993, Stevenson 1978. Birds, rodents, and invertebrates also use these pendulous, hair-like species for nesting materials and shelter (Hayward andRosentreter 1994, Pettersson et al 1995).…”

Forest Structure Within Barred Owl (Strix varia) Home Ranges in the Eastern Cascade Range, Washington

“…Increased moisture tends to increase the abundance of mycorrhizal fungi, a source of food for several prey species including western Red-backed Voles and Flying Squirrels , Maser et al 1985, Carey 1995a. Fungal species differ in the moisture, temperature and nutrients gained from the mineral soil and organic matter (Molina and Trappe 1982, Molina et al 1992, Carey et al 1999a.…”

“…"Lichen litterfall biomass increased with increasing stand complexity and moisture" (Lehmkuhl 2004:381). Lichens are used by "…small mammals (Maser et al, 1985;Rosentreter et al, 1997;Zabel and Waters, 1997), mainly during the winter when plant and fungal food sources are at low levels or unavailable under deep snow" (Lehmkuhl 2004:381). If lichens provide critical nutrients and energy when species are most food stressed, lichen diversity and abundance may affect survival and be one factor in determining population levels of small mammals.…”

Analyzing lichen indicator data in the Forest Inventory and Analysis Program

“…In a typical southeastern forest, 20 to 60 lichen species are recorded in a single FIA plot sample (McCune et al 1997b). Lichens play numerous functional roles in temperate forest ecosystems (Nash 2008), including significant N-fixation and nutrient cycling (Pike 1978) and serving as forage for mammals and arthropods (Dawson et al 1987;Maser et al 1985Maser et al , 1986Rominger and Oldemeyer 1989;Servheen and Lyon 1989;Sharnoff and Rosentreter 2008).…”