No effects of thinning with riparian buffers on terrestrial salamanders in headwater forests 5 to 6 years post-harvest in western Oregon

Abstract

Th ere are emerging concerns for wildlife species associated with forested headwater systems. Given that headwater streams comprise a large portion of the length of fl owing waterways in western Oregon forests, there is a need to better understand how forest management aff ects headwater forest taxa and their habitats. Forest management strategies that consist of only partial canopy removal and retention of riparian buff ers may help ameliorate management eff ects on headwaters, especially relative to historical clearcutting practices. Our study investigated eff ects of upland forest thinning coupled with riparian buff er treatments on riparian and upland headwater forest amphibians, their ground-cover habitat attributes, and species-habitat associations. Amphibian captures and habitat variables were examined 5 to 6 years post-thinning, within riparian and upland forests thinned to 80 trees per acre with streamside-retention buff er widths (~20 ft [6m] wide, each side of streams) and variable-width buff ers (50 ft [15.2 m] minimum width, each side of streams), as well as unthinned reference stands. Distance-from-stream was found to be associated with amphibian abundance. However, no treatment eff ects of thinning or buff er widths were found. We observed that ground surface conditions (e.g., amount of rocky or fi ne substrate, microclimates) likely played a role in determining the response of riparian and upland amphibians to forest thinning along headwater streams. Moderate thinning and preservation of conditions in riparian and nearby upland areas by way of variable-width and streamside-retention buff ers may be suffi cient to maintain suitable habitat and microclimatic conditions vital to amphibian assemblages in managed headwater forests.

Parent Publication

• Density management in the 21st century: west side story

Citation

Kluber, Matthew R.; Olson, Deanna H.; Puettmann, Klaus J. 2013. No effects of thinning with riparian buffers on terrestrial salamanders in headwater forests 5 to 6 years post-harvest in western Oregon. In: Anderson, P.D.; Ronnenberg, K.L., eds. Density management in the 21st century: west side story. Gen. Tech. Rep. PNW-GTR-880. Portland, OR: US Department of Agriculture, Forest Service, Pacific Northwest Research Station: 213-213.