Publications
This list of publications includes peer-review journal articles, official USGS publications series, reports and more authored by scientists in the Ecosystems Mission Area. A database of all USGS publications, with advanced search features, can be accessed at the USGS Publications Warehouse.
Filter Total Items: 42876
Bounded fractional diffusion in geological media: Definition and Lagrangian approximation Bounded fractional diffusion in geological media: Definition and Lagrangian approximation
Spatiotemporal Fractional-Derivative Models (FDMs) have been increasingly used to simulate non-Fickian diffusion, but methods have not been available to define boundary conditions for FDMs in bounded domains. This study defines boundary conditions and then develops a Lagrangian solver to approximate bounded, one-dimensional fractional diffusion. Both the zero-value and non-zero-value...
Authors
Yong Zhang, Christopher T. Green, Eric M. LaBolle, Roseanna M. Neupauer, Hong-Guang Sun
The automated reference toolset: A soil-geomorphic ecological potential matching algorithm The automated reference toolset: A soil-geomorphic ecological potential matching algorithm
Ecological inventory and monitoring data need referential context for interpretation. Identification of appropriate reference areas of similar ecological potential for site comparison is demonstrated using a newly developed automated reference toolset (ART). Foundational to identification of reference areas was a soil map of particle size in the control section (PSCS), a theme in US Soil...
Authors
Travis W. Nauman, Michael C. Duniway
Long-term continuous acoustical suspended-sediment measurements in rivers – Theory, evaluation, and results from 14 stations on five rivers Long-term continuous acoustical suspended-sediment measurements in rivers – Theory, evaluation, and results from 14 stations on five rivers
We have developed a physically based method for using two acoustic frequencies to measure suspended-silt-and-clay concentration, suspended-sand concentration, and suspended-sand median grain size in river cross sections at 15-minute intervals over decadal timescales. The method is strongly grounded in the extensive scientific literature on the scattering of sound by suspensions of small...
Authors
David J. Topping, Scott Wright, Ronald E. Griffiths, David J. Dean
A suspended dive-net technique for catching territorial divers A suspended dive-net technique for catching territorial divers
A variety of methods such as night-lighting and lift nets have been used to catch divers (Gavidae), although 24-hour daylight in the Arctic summer and the remote nature of field sites can make the use of these traditional methods impossible. Our research required capture of adult divers at remote locations in northern Alaska. Here we describe a suspended dive-net technique that we used...
Authors
Brian D. Uher-Koch, Daniel Rizzolo, Kenneth G. Wright, Joel A. Schmutz
A comparative examination of cortisol effects on muscle myostatin and HSP90 gene expression in salmonids A comparative examination of cortisol effects on muscle myostatin and HSP90 gene expression in salmonids
Cortisol, the primary corticosteroid in teleost fishes, is released in response to stressors to elicit local functions, however little is understood regarding muscle-specific responses to cortisol in these fishes. In mammals, glucocorticoids strongly regulate the muscle growth inhibitor, myostatin, via glucocorticoid response elements (GREs) leading to muscle atrophy. Bioinformatics...
Authors
Nicholas J. Galt, Stephen D. McCormick, Jacob Michael Froehlich, Peggy R. Biga
Bacterial genomics reveal the complex epidemiology of an emerging pathogen in arctic and boreal ungulates Bacterial genomics reveal the complex epidemiology of an emerging pathogen in arctic and boreal ungulates
Northern ecosystems are currently experiencing unprecedented ecological change, largely driven by a rapidly changing climate. Pathogen range expansion, and emergence and altered patterns of infectious disease, are increasingly reported in wildlife at high latitudes. Understanding the causes and consequences of shifting pathogen diversity and host-pathogen interactions in these ecosystems...
Authors
Taya L. Forde, Karin Orsel, Ruth N. Zadoks, Roman Biek, Layne G. Adams, Sylvia L. Checkley, Tracy Davison, Jeroen De Buck, Mathieu Dumond, Brett T. Elkin, Laura Finnegan, Bryan J. Macbeth, Cait Nelson, Amanda Niptanatiak, Shane Sather, Helen M. Schwantje, Frank van der Meer, Susan J. Kutz
Response of imperiled Okaloosa darters to stream restoration Response of imperiled Okaloosa darters to stream restoration
The Okaloosa Darter Etheostoma okaloosae is a small percid endemic to six stream drainages in northwestern Florida. The U.S. Fish and Wildlife Service listed Okaloosa Darters as endangered in 1973 and downlisted them to threatened in 2011 because of habitat improvements and increasing abundance across much of their geographic range. Delisting is possible if remaining recovery criteria...
Authors
David B. Reeves, William B. Tate, Howard L. Jelks, Frank Jordan
Low-cost floating emergence net and bottle trap: Comparison of two designs Low-cost floating emergence net and bottle trap: Comparison of two designs
Sampling emergent aquatic insects is of interest to many freshwater ecologists. Many quantitative emergence traps require the use of aspiration for collection. However, aspiration is infeasible in studies with large amounts of replication that is often required in large biomonitoring projects. We designed an economic, collapsible pyramid-shaped floating emergence trap with an external...
Authors
Pete Cadmus, Justin Pomeranz, Johanna M. Kraus
Phenology of the adult angel lichen moth (Cisthene angelus) in Grand Canyon, USA Phenology of the adult angel lichen moth (Cisthene angelus) in Grand Canyon, USA
We investigated the phenology of adult angel lichen moths (Cisthene angelus) along a 364-km long segment of the Colorado River in Grand Canyon, Arizona, USA, using a unique data set of 2,437 light-trap samples collected by citizen scientists. We found that adults of C. angelus were bivoltine from 2012 to 2014. We quantified plasticity in wing lengths and sex ratios among the two...
Authors
Anya N. Metcalfe, Theodore A. Kennedy, Jeffrey D. Muehlbauer
New findings of twisted-wing parasites (Strepsiptera) in Alaska New findings of twisted-wing parasites (Strepsiptera) in Alaska
Strepsipterans are a group of insects with a gruesome life history and an enigmatic evolutionary past. Called ‘twisted-wing parasites’, they are minute parasitoids with a very distinct morphology (Figure 1). Alternatively thought to be related to ichneumon wasps, Diptera (flies), Coleoptera (beetles), and even Neuroptera (net-winged insects) (Pohl and Beutel, 2013); the latest genetic...
Authors
Molly Mcdermott
Do water level fluctuations influence production of walleye and yellow perch young-of-the-year in large northern lakes? Do water level fluctuations influence production of walleye and yellow perch young-of-the-year in large northern lakes?
Many ecological processes depend on the regular rise and fall of water levels (WLs), and artificial manipulations to WL regimes can impair important ecosystem services. Previous research has suggested that differences in WL between late summer and early spring may alter the suitability of shoals used by Walleyes Sander vitreus for spawning. Other species, such as the Yellow Perch Perca...
Authors
James H. Larson, David F. Staples, Ryan P. Maki, Jon M. Vallazza, Brent C. Knights, Kevin E. Peterson
Development of novel microsatellite markers for the Northern Goshawk (Accipiter gentilis) and their utility in cross-species amplification Development of novel microsatellite markers for the Northern Goshawk (Accipiter gentilis) and their utility in cross-species amplification
The Northern Goshawk (Accipiter gentilis) is a large forest raptor with a Holarctic distribution and, in some portions of its range, a species of conservation concern. To augment previously reported genetic markers, 13 novel polymorphic microsatellite markers were developed to establish individual identification and familial relationships, to assess levels of genetic diversity, and to...
Authors
Christy Haughey, George K. Sage, Gabriel Degange, Sarah A. Sonsthagen, Sandra L. Talbot