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PRAIRIEMAP: A GIS database for prairie grassland management in western North America PRAIRIEMAP: A GIS database for prairie grassland management in western North America

The USGS Forest and Rangeland Ecosystem Science Center, Snake River Field Station (SRFS) maintains a database of spatial information, called PRAIRIEMAP, which is needed to address the management of prairie grasslands in western North America. We identify and collect spatial data for the region encompassing the historical extent of prairie grasslands (Figure 1). State and federal agencies...
Authors
Water Resources Division U.S. Geological Survey

Native salamanders and introduced fish: Changing the nature of mountain lakes and ponds Native salamanders and introduced fish: Changing the nature of mountain lakes and ponds

During the last century, many fishless mountain lakes and ponds in the Pacific Northwest were stocked with non-native fish, such as brook trout, for recreational purposes. These introduced fish replaced long-toed and northwestern salamander larvae as the top aquatic vertebrate predator by preying on salamander larvae. This predatory interaction has been shown to reduce the abundances of...
Authors
Gary L. Larson, Robert L. Hoffman

The Amphibian Research and Monitoring Initiative in the Pacific Northwest The Amphibian Research and Monitoring Initiative in the Pacific Northwest

Amphibians have been disappearing from many locations around the world with reports of declines increasing in recent decades. Some of the most dramatic declines have occurred in areas that were thought to be protected from human disturbance. For example, the once-common boreal toad has virtually disappeared from Rocky Mountain National Park in Colorado. Although there has been debate on...
Authors
M. J. Adams

Crater Lake: blue through time Crater Lake: blue through time

Blue is the color of constancy, hence the term true blue. The unearthly blueness of Crater Lake reflects its pristine character and gives scientists a focal point for studying human impacts on aquatic environments over long periods of time. Scientists with the U.S. Geological Survey (USGS), National Park Service, and Oregon State University have systematically studied the lake for the...
Authors
Gary L. Larson, Mark Buktenica, Robert Collier

Food habits of the southwestern willow flycatcher during the nesting season Food habits of the southwestern willow flycatcher during the nesting season

The food habits and prey base of the endangered Southwestern Willow Flycatcher (Empidonax traillii extimus) are not well known. We analyzed prey remains in 59 fecal samples from an intensively-studied population of this flycatcher at the Kern River Preserve in southern California. These samples were collected during the nesting season in 1996 and 1997 from adults caught in mist nets, and...
Authors
Charles A. Drost, Eben H. Paxton, Mark K. Sogge, Mary J. Whitfield

Biological soil crusts in deserts: A short review of their role in soil fertility, stabilization, and water relations Biological soil crusts in deserts: A short review of their role in soil fertility, stabilization, and water relations

Cyanobacteria and cyanolichens dominate most desert soil surfaces as the major component of biological soil crusts (BSC). BSCs contribute to soil fertility in many ways. BSC can increase weathering of parent materials by up to 100 times. Soil surface biota are often sticky, and help retain dust falling on the soil surface; this dust provides many plant-essential nutrients including N, P...
Authors
Jayne Belnap

Impacts of the Brown Tree Snake: Patterns of Decline and Species Persistence in Guam's Avifauna Impacts of the Brown Tree Snake: Patterns of Decline and Species Persistence in Guam's Avifauna

Predation by brown tree snakes (Boiga irregularis ) devastated the avifauna of Guam in the Mariana Islands during the last half of the twentieth century, causing the extirpation or serious reduction of most of the island's 25 resident bird species. Past studies have provided qualitative descriptions of the decline of native forest birds but have not considered all species or presented...
Authors
G.J. Wiles, J. Bart, R.E. Beck, C.F. Aguon
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