Response of Small Mammals to Clearcutting, Burning, and Glyphosate Application in the Oregon Coast Range

Abstract

We sampled amphibians on 3 red alder (Alnus rubra) sites 1 year before and 1 and 2 years after the following treatments were applied to each site: (1) control (uncut), (2) clearcut and broadcast burned, and (3) clearcut, broadcast burned, and then sprayed with the herbicide glyphosate. All sites included uncut riparian buffer strips. For 3 of the 6 species with ≥20 captures in pitfall traps, we did not detect changes in capture rates after clearcutting. Capture rates of ensatinas (Ensatina eschscholtzii) and Pacific giant salamanders (Dicamptodon tenebrosus) decreased after logging. Capture rates of western redback salamanders (Plethodon vehiculum) increased the first year after logging, probably because the salamanders sheltered in pitfalls, but effects on populations were unclear. Logging did not significantly alter capture rates of rough-skin newts (Taricha granulosa), Dunn's salamanders (P. dunni), and red-legged frogs (Rana aurora). Planning the location and timing of clearcuts or other silvicultural practices over a landscape and retaining riparian buffer strips may be necessary to ensure long-term persistence of Pacific giant salamanders. We did not detect any effects of herbicide spraying on capture rates. Capture rates for rough-skin newts and red-legged frogs were higher in uncut red alder stands than in Douglas-fir (Pseudotsuga menziesii) stands sampled in other studies, an indication that, when red alder stands are converted to Douglas-fir, some alders should be left adjacent to streams to provide habitat for these species and other hardwood associates.