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Effectiveness of Postfire Seeding to Reduce Cheatgrass (Bromus tectorum) Growth and Reproduction in Recently Burned Sagebrush Steppe

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...

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Rehabilitation of Salamander Populations in High Mountain Lakes, Mount Rainier National Park

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...

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Distributions and Relative Abundances of Amphibian Taxa Associated with Palustrine Vegetated Wetlands, Ponds, Lakes, Streams and Rivers in Mount Rainier National Park

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...

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Ecological Impact of Introduced Trout on Native Aquatic Communities in Mountain Lakes

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...

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Impact of invasive species on reptiles and amphibians

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...

  • Green turtle (Chelonia mydas L.)

Long-term Assessments of Golden Eagle Nesting Density and Productivity in the Snake River Birds of Prey National Conservation Area

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...

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Density and Size Distribution of Zebra Mussels (Dreissena polymorpha) in the Upper Mississippi River, Pool 8, and Effects of Predation

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...

  • Concrete blocks and cage used to determine the effects of predation on zebra mussels

Nonnative Grass Invasions and Fire in the Sonoran Desert

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...

  • Burned saguaros and yuccas, 1995 Rio Fire in the Phoenix area

Influence of Timber Harvest and Floods on the Distribution of Exotic Riparian Plants

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...

  • Scotch Broom (Cytisus scoparius) colonizes bare ground areas

Fire and Invasive Annual Grasses in Western Ecosystem

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...

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Impact of Fire and Grazing on Diversity and Invasion in Sierran Forests

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...

  • Photo of Ponderosa pine forest fire with cheatgrass-dominated understory being managed

Wildfire and Invasive Plants

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...

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