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Providing evidence to improve practice

Individual study: Stream buffers ameliorate the effects of timber harvest on amphibians in the Cascade Range of southern Washington, USA

Published source details

Pollett K.L., MacCracken J.G. & MacMahon J.A. (2010) Stream buffers ameliorate the effects of timber harvest on amphibians in the Cascade Range of southern Washington, USA. Forest Ecology and Management, 260, 1083-1087


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Retain riparian buffer strips during timber harvest Amphibian Conservation

A replicated, controlled, site comparison study in 2001 of amphibians in 41 forest streams in Washington, USA (Pollett, MacCracken & MacMahon 2010) found that where buffers were retained during clearcutting, densities of two of three species were significantly higher. Densities were significantly higher with buffers than without for tailed frogs Ascaphus truei (0.4 vs 0/m2) and cascade torrent salamander Rhyacotriton cascadae (0.5 vs 0.2). For both species, densities were significantly higher in unharvested forests (0.7 and 1.5/m2 respectively) but not secondary forests (0.2 and 0.6). In contrast, giant salamander Dicamptodon spp. densities were significantly lower in buffered (0.2/m2) than unbuffered streams and secondary forests (0.3/m2). Densities in unharvested forests (0.2) were significantly lower than the average for managed forests. Nine to 12 streams in each of four management types were sampled: clearcuts (≤10 years old) with 5–23 m wide buffers or without buffers, second-growth forest (≥35 years old) and unharvested forest. Amphibians were monitored within six 2 m long plots within 45–55m sub-sections of streams in June–August 2001.