Treesearch

1. Conservation of the federally endangered Roanoke logperch (Percina rex, Jordan and Evermann) necessitates protection of habitat that is critical for all age classes. We examined habitat use patterns of individual logperch to determine: (1) if age classes of logperch in the Nottoway and Roanoke Rivers exhibit habitat selectivity, (2) if age classes differ in habitat use, and (3) if ontogenetic patterns of habitat use differ between the Roanoke and Nottoway river populations. 2. In the summers of 2000 and 2001, we observed 17 young-of-year (YOY) logperch [8 cm TL) in the upper Roanoke...

Bayesian inference facilitated structured interpretation of a nonreplicated, experience-based survey of potential nesting habitat for bald eagles (Haliaeetus leucocephalus) along the five Great Lakes shorelines. We developed a pattern recognition (PATREC) model of our aerial search image with six habitat attributes: (a) tree cover, (b) proximity and (c) type/amount of human disturbance, (d) potential foraging habitat/shoreline irregularity, and suitable trees for (e) perching and (f) nesting. Tree cover greater than 10 percent, human disturbance more than 0.8 km away, a ratio of total to...

The 1964 Wilderness Act and subsequent wilderness legislation have resulted in the designation of over 106 million acres of the United States as wilderness. Charged with the responsibility of protecting a significant portion of federal lands as wilderness, the federal land management agencies with responsibility for wilderness stewardship (Bureau of Land Management, Fish and Wildlife Service, Forest Service, and National Park Service) have often struggled with how to translate legislative direction into policy and management practices. The direction to manage wilderness in a manner that...

Selection of suitable locally available materials to build strong and durable roads with aggregate surfaces is desired to minimize road construction and maintenance costs and to minimize the detrimental effects of sedimentation. Eighteen aggregates were selected from local sources in Idaho, Oregon, South Dakota, and Washington State. Aggregate was placed in shallow metal frames and compacted to simulate a forest road. The levels of runoff and sediment from a high-intensity, long-duration simulated rainstorm were measured. The material tests selected for use in the study included ones that...

Mass failure is one of the most common failures of low-volume roads in mountainous terrain. Current methods for evaluating stability of these roads require a geotechnical specialist. A stability analysis program, XSTABL, was used to estimate the stability of 3,696 combinations of road geometry, soil, and groundwater conditions. A sensitivity analysis was carried out to find the most important site-specific variables in estimating slope stability, and two regression equations were developed to predict the factor of safety (FS) for a given road, one with the groundwater below the road fill...

Many of the forests in the U.S. and elsewhere in the world are source areas for water. The quantity and quality of this water are major public concerns. In a forested watershed, any road segment, harvesting operation, or other management activity can adversely impact forest streams. These disturbances are distributed in both time and space. The disturbance in the first year may have minimal impact on the hydrologic integrity of the watershed, but if the disturbance in the following year is added to the first, and the disturbance in year 3 added to those in years 1 and 2, the net effect may...

Wilderness preservation is strongly supported by the American people (Cordell et al. 1998) and a substantial portion of the public domain has been allocated to wilderness. The Wilderness Act of 1964 and more than 135 subsequent wilderness bills have created a National Wilderness Preservation System of 661 wilderness areas with a total acreage that exceeds 106 million acres. The proportion of the United States currently designated as wilderness is 4.5%. Designated wilderness constitutes more than 16% of lands owned by the federal government, 57% of National Park Service lands, 22% of Fish...

Increased runoff and erosion commonly occur after wildfires with the onset of precipitation events. Various erosion mitigation treatments are often used after wildfires to reduce flooding and sedimentation. The effectiveness of these treatments has not been well documented in the literature; therefore we undertook a rapid response approach (within four weeks following fire suppression) to install small catchment monitoring systems to compare treatment effectiveness. A paired watershed approach uses two adjacent and similar catchments (5-20 ac) after wildfires, treating one catchment and...

Wildfire is an important ecological process and management issue on western rangelands. Major unknowns associated with wildfire are its affects on vegetation and soil conditions that influence hydrologic processes including infiltration, surface runoff, erosion, sediment transport, and flooding. Post wildfire hydrologic response was studied in big sagebrush plant communities on steep slopes with coarse-textured soils. Significant rill erosion was observed following both thunderstorm and rapid snowmelt events. Rainfall simulation and controlled overland flow techniques were used to study...

Western white pine (Pinus monticola) is an economically and ecologically important species from western North America that has declined over the past several decades mainly due to the introduction of blister rust (Cronartium ribicola) and reduced opportunities for regeneration. Amplified fragment length polymorphism (AFLP) was used to assess the genetic variation in northern Idaho populations of western white pine (including rust-resistant breeding stock) in relation to blister rust. A total of 176 individuals from four populations was analyzed using 163 AFLP loci. Within populations, an...