Pacific Northwest salmonids are adapted to natural disturbance regimes that create dynamic habitat patterns over space and through time. However, human land use, particularly long-term fire suppression, has altered the intensity and frequency of wildfire in forested upland and riparian areas.
Increasingly frequent “megafires” in North America's dry forests have prompted proposals to restore historical fire regimes and ecosystem resilience. Restoration efforts that reduce tree densities (eg via logging) could have collateral impacts on declining old-forest species, but whether these risks outweigh the potential effects of large, severe fires remains uncertain.
In this study, researchers developed models of freshwater habitat for spring Chinook Salmon in pre- and post-fire scenarios in the Wenatchee River sub-basin of central Washington, where a large number of wildfires have occurred in the past 30 years. They predicted changes in in-stream wood, sediment, and water temperature as a result of wildfires and modeled their influence on habitat quality for three life stages (egg/fry, juvenile, and adult) of spring Chinook Salmon. They also compared their model results with the current and historic distribution of spring Chinook Salmon to better understand if decreasing populations are distributed in ways that correlate with fire impacts on habitats.
Fire is a prevalent feature of many landscapes and has numerous and complex effects on geological, hydrological, ecological, and economic systems. In some regions, the frequency and intensity of wildfire haveincreased in recent years and are projected to escalate with predicted climatic and landuse changes.
Greater sage-grouse (Centrocercus urophasianus; hereinafter, sage-grouse) are a sagebrush obligate species that has declined concomitantly with the loss and fragmentation of sagebrush ecosystems across most of its geographical range. The species currently is listed as a candidate for federal protection under the Endangered Species Act (ESA).
Severe wildfires infrequently occur in large heterogeneous riparian valleys. Riparian areas may affect fire behavior and the pattern of burning due to saturated soils and patchy fuels that may have high moisture content in live and dead stems.
Habitat suitability models can provide guidelines for species conservation by predicting where species of interest are likely to occur. Presence-only models are widely used but typically provide only relative indices of habitat suitability (HSIs), necessitating rigorous evaluation often using independently collected presence-absence data.
Linked atmospheric and wildfire changes will complicate future management of native coldwater fishes in fire-pronelandscapes, and new approaches to management that incorporate uncertainty are needed to address this challenge.
National Forests in the dry forest provinces on the east‐side of the Oregon and Washington Cascades have been managed under the guidelines of local Forest Plans and the Northwest Forest Plan (NWFP), both of which specify large areas of late‐successional reserves (LSRs).
We used 1 year of pre-fire and 4 years of post-fire data to quantify changes in the occurrence of birds at burned and unburned sites in a southern Oregon watershed after a 2500-ha wildfire. Our objectives were to identify bird species that increased or decreased as a result of this mixed-severity fire.