WRC Home > Research > Watershed Management

 

Effect of riparian forest harvest on instream habitat and fish and invertebrate communities

PIs: Ray Newman, Bruce Vondracek, and James Perry, Professors, Fisheries, Wildlife, and Conservation Biology

Funding Source: USGS-WRRI 104B/ CAIWQ Competitive Grants Program

Project Duration: 3/1/02- 2/28/05

Best management practices for timber harvest are often implemented to allow forest harvest while protecting the aquatic resource, however, the effectiveness of these practices is rarely evaluated. The aim of the proposed research is to evaluate site-based effects associated with applying various riparian management practices (varying density of residual standing trees within a standard RMZ and filter strip width) aquatic habitat, macroinvertebrates, and fish. We will use an experimental manipulation to apply four levels of riparian harvest (riparian control, low riparian harvest, moderate riparian harvest, and high riparian harvest) to replicate five stream sites. At these sites we will evaluate effects of riparian forest harvest on fish and invertebrate habitat (temperature, sediment composition and embeddedness, depth, width, cover, bank stability, canopy coverage, woody debris, etc.), benthic macroinvertebrates (rapid bioassessment protocol) and stream fish communities (relative abundance, species richness and an Index of Biotic Integrity). Sites will be sampled above, within and below the treatment area the year prior to harvest and the year after harvest to provide an initial assessment of the effects of harvest treatment and to establish a baseline for longer-term assessment. These results will be used to determine the effects of different levels of riparian harvest on instream processes and to inform water quality managers and policy makers of the efficacy of current and alternative forest harvest best management practices to protect aquatic resources. This research is supported by a grant from the WRC.