Publications
Filter Total Items: 167
Quantitative evidence for the effects of multiple drivers on continental-scale amphibian declines
Since amphibian declines were first proposed as a global phenomenon over a quarter century ago, the conservation community has made little progress in halting or reversing these trends. The early search for a “smoking gun” was replaced with the expectation that declines are caused by multiple drivers. While field observations and experiments have identified factors leading to increased local extin
Authors
Evan H. Campbell Grant, David A. W. Miller, Benedikt R. Schmidt, M. J. Adams, Staci M. Amburgey, Thierry A. Chambert, Sam S. Cruickshank, Robert N. Fisher, David M. Green, Blake R. Hossack, Pieter T.J. Johnson, Maxwell B. Joseph, Tracy A. G. Rittenhouse, Maureen E. Ryan, J. Hardin Waddle, Susan C. Walls, Larissa L. Bailey, Gary M. Fellers, Thomas A. Gorman, Andrew M. Ray, David S. Pilliod, Steven J. Price, Daniel Saenz, Walt Sadinski, Erin L. Muths
Spatial and temporal patterns of mercury concentrations in freshwater fish across the Western United States and Canada
Methylmercury contamination of fish is a global threat to environmental health. Mercury (Hg) monitoring programs are valuable for generating data that can be compiled for spatially broad syntheses to identify emergent ecosystem properties that influence fish Hg bioaccumulation. Fish total Hg (THg) concentrations were evaluated across the Western United States (US) and Canada, a region defined by e
Authors
Collin A. Eagles-Smith, Joshua T. Ackerman, James J. Willacker, Michael T. Tate, Michelle A. Lutz, Jacob Fleck, A. Robin Stewart, James G. Wiener, David C. Evers, Jesse M. Lepak, Jay A. Davis, Colleen Flanagan Pritz
Avian mercury exposure and toxicological risk across western North America: A synthesis
Methylmercury contamination of the environment is an important issue globally, and birds are useful bioindicators for mercury monitoring programs. The available data on mercury contamination of birds in western North America were synthesized. Original data from multiple databases were obtained and a literature review was conducted to obtain additional mercury concentrations. In total, 29219 origi
Authors
Joshua T. Ackerman, Collin A. Eagles-Smith, Mark P. Herzog, C. Alex Hartman, Sarah H. Peterson, David C. Evers, Allyson K. Jackson, John E. Elliott, Stacy S. Vander Pol, Colleen E. Bryan
Hg concentrations in fish from coastal waters of California and Western North America
The State of California conducted an extensive and systematic survey of mercury (Hg) in fish from the California coast in 2009 and 2010. The California survey sampled 3483 fish representing 46 species at 68 locations, and demonstrated that methylHg in fish presents a widespread exposure risk to fish consumers. Most of the locations sampled (37 of 68) had a species with an average concentration abo
Authors
Jay Davis, John Ross, Shira Bezalel, Lawrence Sim, Autumn Bonnema, Gary Ichikawa, Wes Heim, Kenneth C Schiff, Collin A. Eagles-Smith, Joshua T. Ackerman
Conditional vulnerability of plant diversity to atmospheric nitrogen deposition across the United States
Atmospheric nitrogen (N) deposition has been shown to decrease plant species richness along regional deposition gradients in Europe and in experimental manipulations. However, the general response of species richness to N deposition across different vegetation types, soil conditions, and climates remains largely unknown even though responses may be contingent on these environmental factors. We ass
Authors
Samuel M. Simkin, Edith B. Allen, William D. Bowman, Christopher L. Clark, Jayne Belnap, Matthew L. Brooks, Brian S. Cade, Scott L. Collins, Linda H. Geiser, Frank S. Gilliam, Sarah E. Jovan, Linda H. Pardo, Bethany K. Schulz, Carly J. Stevens, Katharine N. Suding, Heather L. Throop, Donald M. Waller
Quasi-extinction risk and population targets for the Eastern, migratory population of monarch butterflies (Danaus plexippus)
The Eastern, migratory population of monarch butterflies (Danaus plexippus), an iconic North American insect, has declined by ~80% over the last decade. The monarch’s multi-generational migration between overwintering grounds in central Mexico and the summer breeding grounds in the northern U.S. and southern Canada is celebrated in all three countries and creates shared management responsibilities
Authors
Brice X. Semmens, Darius J. Semmens, Wayne E. Thogmartin, Ruscena Wiederholt, Laura Lopez-Hoffman, James E. Diffendorfer, John M. Pleasants, Karen S. Oberhauser, Orley R. Taylor
Hydrologic indicators of hot spots and hot moments of mercury methylation potential along river corridors
The biogeochemical cycling of metals and other contaminants in river-floodplain corridors is controlled by microbial activity responding to dynamic redox conditions. Riverine flooding thus has the potential to affect speciation of redox-sensitive metals such as mercury (Hg). Therefore, inundation history over a period of decades potentially holds information on past production of bioavailable Hg.
Authors
Michael B. Singer, Lee R. Harrison, Patrick M. Donovan, Joel D. Blum, Mark C. Marvin-DiPasquale
Surface-air mercury fluxes across Western North America: A synthesis of spatial trends and controlling variables
Mercury (Hg) emission and deposition can occur to and from soils, and are an important component of the global atmospheric Hg budget. This paper focuses on synthesizing existing surface-air Hg flux data collected throughout the Western North American region and is part of a series of geographically focused Hg synthesis projects. A database of existing Hg flux data collected using the dynamic flux
Authors
Chris S. Eckley, Michael T. Tate, Che-Jen Lin, Mae S. Gustin, Stephen Dent, Collin A. Eagles-Smith, Michelle A. Lutz, Kimberly Wickland, Bronwen Wang, John E. Gray, Grant Edwards, David P. Krabbenhoft, David B. Smith
An alternative framework for responding to the amphibian crisis
Volumes of data illustrate the severity of the crisis affecting amphibians, where > 32% of amphibians worldwide are threatened with declining populations. Although there have been isolated victories, the current approach to the issue is unsuccessful. We suggest that a radically different approach, something akin to human emergency response management (i.e. the Incident Command System), is one alte
Authors
Erin L. Muths, Robert N. Fisher
Implications of projected climate change for groundwater recharge in the western United States
Existing studies on the impacts of climate change on groundwater recharge are either global or basin/location-specific. The global studies lack the specificity to inform decision making, while the local studies do little to clarify potential changes over large regions (major river basins, states, or groups of states), a scale often important in the development of water policy. An analysis of the p
Authors
Thomas Meixner, Andrew H. Manning, David A. Stonestrom, Diana M. Allen, Hoori Ajami, Kyle W. Blasch, Andrea E. Brookfield, Christopher L. Castro, Jordan F. Clark, David Gochis, Alan L. Flint, Kirstin L. Neff, Rewati Niraula, Matthew Rodell, Bridget R. Scanlon, Kamini Singha, Michelle Ann Walvoord
Crustal permeability
Permeability is the primary control on fluid flow in the Earth’s crust and is key to a surprisingly wide range of geological processes, because it controls the advection of heat and solutes and the generation of anomalous pore pressures. The practical importance of permeability – and the potential for large, dynamic changes in permeability – is highlighted by ongoing issues associated with hydrau
Deserts
The deserts of California (Lead photo, Fig. 1) occupy approximately 38% of California’s landscape (Table 1) and consist of three distinct deserts: the Great Basin Desert, Mojave Desert, and Colorado Desert, the latter of which is a subdivision of the Sonoran Desert (Brown and Lowe 1980). The wide range of climates and geology found within each of these deserts result in very different vegetative c
Authors
Jayne Belnap, Robert H. Webb, Todd C. Esque, Matthew L. Brooks, Lesley A. DeFalco, James A. MacMahon