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This book on Ecological Assessment of Selenium in the Aquatic Environment synthesizes and advances the state-of-the-science regarding this unique metalloid and identies critical knowledge gaps. Assessment methods appropriate for other metals and metalloids are not always appropriate for selenium (Se). Selenium requires site-specific risk assessments to a much greater extent...

For many years, amphibians were understudied in the ecotoxicological literature. In 1989, the Canadian Wildlife Service published a comprehensive review of studies examining the effects of contaminants on amphibians (Power et al. 1989). Just 10 years later, the same organization published an updated review that included twice the number of...

The Least Bittern (Ixobrychus exilis) and the Pied-billed Grebe (Podilymbus podiceps) are secretive marsh bird species that breed in the Illinois and Upper Mississippi River Valleys. Marsh bird surveys were conducted on public and private wetlands in this region during the breeding seasons of 2006 and 2007. Detection probability (ῥ)...

River otters (Lontra canadensis) are important predators in aquatic ecosystems, but few studies quantify their prey consumption. We trapped crayfish monthly as an index of availability and collected otter scat for diet analysis in the Ozark Mountains of northwestern Arkansas, USA. We measured otter daily energy expenditure (DEE) with the...

Alphaviruses (Togaviridae) infect wild birds, but clinical illness and death attributable to virus in naturally infected birds is rarely reported, particularly for small passerine species or nestlings. Buggy Creek virus is a unique alphavirus in the Western equine encephalomyelitis virus (WEEV) complex that is vectored by the cimicid swallow bug (Oeciacus vicarius), an ectoparasite...

No abstract available....

Based on the work and contributions of 46 scientists, managers, and policymakers, Ecological Assessment of Selenium in the Aquatic Environment documents the state of the science and explores how to use this information when assessing and managing the environmental effects of Se. A focused discussion on the fate and effects...

A model with a small amount of numerical dispersion was used to represent saltwater 7 intrusion in a homogeneous aquifer for a 10-year historical calibration period with one 8 groundwater withdrawal location followed by a 10-year prediction period with two groundwater 9 withdrawal locations. Time-varying groundwater concentrations at arbitrary locations...

Isotopes are a potentially powerful component of monitoring and assessment programs aimed at quantifying and mitigating alterations to environments from human activities. In particular, isotopic techniques have proved useful for tracing sources and sinks of various pollutants in large river basins, wetlands, and airsheds. Many of these studies have been...

No abstract available....

Beak abnormalities are rare among adult birds and, typically, are not widespread in a given population, within a region, or across multiple species. A high concentration of beak deformities was recently documented in Black-capped Chickadees (Poecile atricapillus) and other resident avian species in Alaska. We describe a parallel condition in...

The terminus of Columbia Glacier, Alaska, unexpectedly became ungrounded in 2007 during its prolonged retreat. Visual observations showed that calving changed from a steady release of low-volume bergs, to episodic flow-perpendicular rifting, propagation, and release of very large icebergs - a style reminiscent of calving from ice shelves. Here, we...

This 18-month field study addresses the seasonal and spatial patterns and processes controlling methylmercury (MeHg) production, bioaccumulation, and export from natural and agricultural wetlands of the Yolo Bypass Wildlife Area (YBWA). The data were collected in conjuntion with a Proposition 40 grant from the State Water Resources Control Board in...

The number of invasive exotic plant species establishing in the United States is continuing to rise. When prevention of exotic species from entering into a country fails at the national level and the species establishes, reproduces, spreads, and becomes invasive, the most successful action at a local level is early...

Acoustic and electrical image logs in fractured granitic rocks penetrated by U.S. Navy well 58A-10, Coso Wash, in the eastern margin of the Coso geothermal field, California, were compared to evaluate their relative ability to characterize fractures and fault rock textures and to measure stress orientations from borehole failure. Electrical...

Numerical modeling is needed to predict environmental temperatures, which affect a number of biota in southern Florida, U.S.A., such as the West Indian manatee (Trichechus manatus), which uses thermal basins for refuge from lethal winter cold fronts. To numerically simulate heat-transport through a dynamic coastal wetland region, an algorithm was...

The purpose of this chapter is to provide a summary of issues and findings related to the potential effects of coalbed natural gas (CBNG) development on fish and other aquatic resources. We reviewed CBNG issues from across the United States and used the Powder River Basin of Wyoming as a case study to...

No abstract available. ...

We designed a digital underwater video camera system to monitor nesting centrarchid behavior in the Tallapoosa River, Alabama, 20 km below a peaking hydropower dam with a highly variable flow regime. Major components of the system included a digital video recorder, multiple underwater cameras, and specially fabricated substrate stakes. The...

A mark-recapture field study was conducted to determine fish passage at 5 concrete box culverts and 5 low-water crossings (concrete slabs vented by culverts) as well as 10 control sites (below a natural riffle) in Flint Hills streams of northeastern Kansas. Additionally, we tested the upstream passage of four fish...

Conservation planning requires identifying pertinent habitat factors and locating geographic locations where land management may improve habitat conditions for high priority species. I derived habitat models and mapped predicted abundance for the Golden-winged Warbler (Vermivora chrysoptera), a species of high conservation concern, using bird counts, environmental variables, and hierarchical models...

There is a need to provide agency leaders, elected officials, and the general public with summary information regarding the effects of large wildfires. Recently, the Wildland Fire Leadership Council (WFLC), which implements and coordinates National Fire Plan (NFP) and Federal Wildland Fire Management Policies adopted a strategy to monitor the...

An experiment for studying the effects of sediment dredging on denitrification in sediments was carried out through a one-year incubation of undredged (control) and dredged cores in laboratory. Dredging the upper 30 cm of sediment can significantly affect physico-chemical characteristics of sediments. Less degradation of organic matter in the dredged...

Background Phenotypic and molecular genetic data often provide conflicting patterns of intraspecific relationships confounding phylogenetic inference, particularly among birds where a variety of environmental factors may influence plumage characters. Among diurnal raptors, the taxonomic relationship of Buteo jamaicensis harlani to other B. jamaicensis subspecies has been long debated because of the polytypic nature of the...