Pacific Northwest Research Station - Ecological Process & Function - Wildlife Ecology Team

Sensitive Species Research within the Wildlife Ecology Team

Stream-associated Amphibian Microhabitat Study (SAMS)

This study is an outgrowth of the Riparian Ecosystem Management Study (REMS). However, it specifically addresses amphibian microhabitat use by all nine streamassociated amphibian species in the Olympic Peninsula, the Willapa Hills, and the southern Washington Cascades. Based on our findings (Bisson and others, in prep.; Raphael and others, in prep.;), and that of other researchers (Bury and Corn 1988, Corn and Bury 1989, Welsh 1990, Welsh and Ollivier 1998), amphibians are probably the best vertebrate bioindicators of stream and streamside health. Stream-associated amphibians as a group are recognized in the Northwest Forest Plan as being sensitive to environmental perturbation, and riparian reserves were established, in part, to ameliorate the impact of adjacent stand harvest. It was assumed that these buffers would retain the integrity of microhabitats, but this has not been demonstrated. The primary objectives are: (1) to determine patterns of microhabitat use and mechanisms of coexistence among species of stream-associated amphibians, and (2) to determine microhabitat differences of stream Wildlife Ecology Team Problem Analysis October 10, 2002 Page 10 of 33 amphibian communities among the 3 centers of distribution in western Washington. The methods used are the same for amphibian portion of REMS, including in-stream belt surveys, stream to upland transects, and systematic spotlight surveys (Jones and Raphael in press; this method was experimental in REMS). Unlike REMS, which primarily addresses stand- to landscape level responses, this study addresses microhabitat-scale issues. Results will be presented through workshops, conferences, presentations at scientific meetings, and publication in peer-reviewed journals. The team lead on this study, Larry Jones, has since left to assume another position but he will complete the research reports.

Team Lead: Lawrence L. C. Jones and Martin G. Raphael.

Cooperators: Marc Hayes and Timothy Quinn, Washington Department of Fish and
Wildlife; N. Phil Peterson, Simpson Timber Company; Washington Department of
Natural Resources.

Amphibians in managed, second-growth Douglas-fir forests of western Washington

The maintenance and restoration of biodiversity has been identified as a critical component of federal, state, and private forest management policies in the Pacific Northwest. Amphibian populations, in particular, are believed to be at risk from the effects of timber harvesting in both upland and riparian zones. Information that could be used to evaluate either the short- or long-term effects of timber harvesting and subsequent silvicultural practices on amphibians in this region is scarce, however. An extensive program of research on wildlife communities in unmanaged, late-seral Douglas-fir forests was conducted by the Pacific Northwest Research Station’s Old-Growth Wildlife Habitat Research Program in the mid-1980's, but the applicability of those studies in managed forests was limited. Stand ages varied from 30 to 900 years, but all had resulted from catastrophic wildfires and contained residual structures from the previous stand, such as large decadent trees, snags, and logs. Amphibian abundances generally did not differ significantly among age classes sampled, indicating that habitat conditions that limit forest amphibian populations occur above threshold levels in all age classes of unmanaged, lateseral Douglas-fir forests. Thus, to understand the potential effects of forest management on terrestrial amphibians in the Douglas-fir region, similar studies need to be conducted in intensively managed forest landscapes where late-seral structural elements are lacking or persist at low levels. The objectives of this study are to (1) describe the species composition and relative abundances of amphibians occurring in different age classes of managed, second-growth Douglas-fir forest, (2) determine if species richness, biomass, relative abundance, or body condition indices differ significantly among age classes, and (3) explore amphibian habitat relationships in intensively managed forests at both the stand and landscape scales. Wildlife Ecology Team Problem Analysis October 10, 2002 Page 11 of 33

Team lead: Keith B. Aubry
Cooperators: Washington Department of Natural Resources, University of Washington,
Weyerhaeuser, Champion Pacific Timberlands

USDA Forest Service - Pacific Northwest Research Station - Olympia Forestry Sciences Laboratory
Last Modified: Monday, 31 January 2011 at 16:52:53 EST