Publisher: USGS | Science Center: Western Ecological Research Center (WERC, Sacramento) | Format: URL
www.werc.usgs.gov — This web resource addresses the positive relationship between cheatgrass (Bromus tectorum) and fire frequency as a major concern for land managers in semi-arid shrublands throughout western North America, particularly in Great Basin sagebrush steppe. Management tools are needed to break this cycle, and in this project we will evaluate the use of More...
Publisher: USGS | Science Center: Forest and Rangeland Ecosystem Science Center (FRESC, Corvallis) | Format: URL
fresc.usgs.gov — The National Park Service has stated that declining amphibian populations are the top priority for research in the National Park System. Salamanders are a native vertebrate predator in high-mountain lakes throughout the western US, especially in many small lakes naturally barren of fish. This issue overview demonstrates the potential for using More...
Publisher: USGS | Science Center: Forest and Rangeland Ecosystem Science Center (FRESC, Corvallis) | Format: URL
fresc.usgs.gov — Little is known about the amphibian taxa associated with streams, lakes, ponds, and wetlands in Mount Rainier National Park (MORA). This issue overview addresses the concerns about the possible impacts of introduced trout on amphibian taxa, and park management's interest in documenting current distribution and abundance of amphibian taxa in the More...
Publisher: USGS | Science Center: Forest and Rangeland Ecosystem Science Center (FRESC, Corvallis) | Format: URL
fresc.usgs.gov — Fish introductions have been implicated in the disappearance of amphibian communities and in the alteration of zooplankton communities. Furthermore, the presence and abundance of amphibian larvae and zooplankton in mountain lakes are directly related to nutrient concentrations in the aquatic environment, as well as enhancement to recreational More...
Publisher: USGS | Science Center: Western Ecological Research Center (WERC, Sacramento) | Format: URL
www.werc.usgs.gov — Native amphibian and reptile populations worldwide are under threat from exotic invasive species of plants and animals, including other reptiles and amphibians. As habitats are changed and plant community organization is modified by exotic species, delicate relationships between plants and animals are altered or eliminated, creating a negative More...
Publisher: USGS | Science Center: Forest and Rangeland Ecosystem Science Center (FRESC, Corvallis) | Format: URL
srfs.wr.usgs.gov — The Snake River Birds of Prey National Conservation Area (NCA) has undergone massive habitat changes since 1980. Occupancy and productivity data have been collected at all eagle territories in the NCA since 1971, providing a wealth of background information. This issue overview continues the long-term assessments of territory occupancy and More...
Publisher: USGS | Science Center: Upper Midwest Environmental Sciences Center (UMESC, LaCrosse) | Format: URL
www.umesc.usgs.gov — The invasion of the exotic zebra mussel (Dreissena polymorpha) into the Upper Mississippi River (UMR) was documented in 1991 with the discovery of a zebra mussel in Pool 8 near La Crosse, Wisconsin. Zebra mussels have expanded their range throughout the UMR because of their high reproductive rate, the free-swimming veliger stage, and ease of More...
Publisher: USGS | Science Center: Western Ecological Research Center (WERC, Sacramento) | Format: URL
www.werc.usgs.gov — This issues overview and its resources deal with the spread of nonnative grasses in the Sonoran desert of Arizona has increased the risk of devastating fires by ignited fuel. The saguaro cactuses and desert tortoises have suffered catastrophic population losses as a result of these fires fueled by nonnative grasses. Read more about nonnative More...
Publisher: USGS | Science Center: Western Ecological Research Center (WERC, Sacramento) | Format: URL
www.werc.usgs.gov — Riparian vegetation is intimately linked to the stream and river channels along which it grows. This project addresses the status of the riparian zone along Redwood Creek north coastal California, and answers three questions: 1) How have the overstory riparian conditions changed in Redwood Creek and major tributaries since the advent of timber More...
Publisher: USGS | Science Center: Western Ecological Research Center (WERC, Sacramento) | Format: URL
www.werc.usgs.gov — This resource provides an overview of the research on ways to prevent invasive annual grass invasions and restore invaded habitats, which has independently and repeatedly been identified by all land management agencies as a top national research priority. Annual grasses have invaded a number of shrub and forest ecosystems in western North America More...
Publisher: USGS | Science Center: Western Ecological Research Center (WERC, Sacramento) | Format: URL
www.werc.usgs.gov — USGS scientists are conducting research through the Joint Fire Science Program to determine if fire contributes most to plant invasion in low-nutrient soils by making available increased nutrients that invasive grasses may exploit more effectively than native flora. Soil nutrient changes can vary widely depending on soil properties and the amount More...
Publisher: USGS | Science Center: Fort Collins Science Center (FORT, Ft. Collins) | Format: URL
www.fort.usgs.gov — The severity of wildfires in recent years has increased public awareness and concern about a fuel build-up in western U.S. forests. Federal land management agencies are responding by greatly expanding programs to reduce hazardous fuels, but little is know about the efficacy of fuel treatments for mitigating wildfire severity or the influence of More...