Use of Arboreal Nests of Tree Voles (Arborimus spp.) by Amphibians.

.—We describe occupancy of arboreal nests of Tree Voles (Arborimus spp.) by four amphibian species in westernOregon and northern California, including Clouded Salamanders (Aneides ferreus), Arboreal Salamanders (Aneides lugubris),Pacific Tree Frogs (Pseudacris regilla), and a California Giant Salamander (Dicamptodon ensatus). These observations suggestthat occupancy of the canopy of Douglas-fir (Pseudotsuga menziesii) forests by arboreal amphibians may be a more commonphenomenon than is generally known. We suggest that salamanders and Pacific Tree Frogs may be attracted to occupied volenests because they support large populations of invertebrate prey and provide a damp microenvironment. Tree Voles maybenefit from the presence of amphibians in their nests because the amphibians feed on mites and other arthropods thatcommonly infest vole nests. We suggest that more detailed studies are needed to determine the extent of arboreal activity bysalamanders in Douglas-fir forests.