Skip to main content
U.S. flag

An official website of the United States government

Publications

Browse publications authored by our scientists.  Publications available are: USGS-authored journal articles, series reports, book chapters, other government publications, and more. **Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.

Filter Total Items: 4116

Assessing potential health risks to fish and humans using mercury concentrations in inland fish from across western Canada and the United States

Fish represent high quality protein and nutrient sources, but Hg contamination is ubiquitous in aquatic ecosystems and can pose health risks to fish and their consumers. Potential health risks posed to fish and humans by Hg contamination in fish were assessed in western Canada and the United States. A large compilation of inland fish Hg concentrations was evaluated in terms of potential health ris
Authors
Jesse M. Lepak, Mevin Hooten, Collin A. Eagles-Smith, Michael T. Tate, Michelle A. Lutz, Joshua T. Ackerman, James J. Willacker, Allyson K. Jackson, David C. Evers, James G. Wiener, Colleen Flanagan Pritz, Jay Davis

Sea lamprey carcasses exert local and variable food web effects in a nutrient-limited Atlantic coastal stream

Resource flows from adjacent ecosystems are critical in maintaining structure and function of freshwater food webs. Migrating sea lamprey (Petromyzon marinus) deliver a pulsed marine-derived nutrient subsidy to rivers in spring when the metabolic demand of producers and consumers are increasing. However, the spatial and temporal dynamics of these nutrient subsidies are not well characterized. We u
Authors
Daniel M. Weaver, Stephen M. Coghlan, Joseph D. Zydlewski

Pacific lamprey (Entosphenus tridentatus) ammocoetes exposed to contaminated Portland Harbor sediments: Method development and effects on survival, growth, and behavior

Many anthropogenic disturbances have contributed to the decline of Pacific lampreys (Entosphenus tridentatus), but potential negative effects of contaminants on lampreys are unclear. Lamprey ammocoetes are the only detritivorous fish in the lower Willamette River, Oregon, USA, and have been observed in Portland Harbor sediments. Their long benthic larval stage places them at risk from the effects
Authors
Julia R. Unrein, Jeffrey M. Morris, Rob S. Chitwood, Joshua Lipton, Jennifer Peers, Stan van de Wetering, Carl B. Schreck

Effects of thyroid endocrine manipulation on sex-related gene expression and population sex ratios in Zebrafish

Thyroid hormone reportedly induces masculinization of genetic females and goitrogen treatment delays testicular differentiation (ovary-to-testis transformation) in genetic males of Zebrafish. This study explored potential molecular mechanisms of these phenomena. Zebrafish were treated with thyroxine (T4, 2 nM), goitrogen [methimazole (MZ), 0.15 mM], MZ (0.15 mM) and T4 (2 nM) (rescue treatment), o
Authors
Prakash Sharma, Song Tang, Gregory D. Mayer, Reynaldo Patiño

Common carp disrupt ecosystem structure and function through middle-out effects

Middle-out effects or a combination of top-down and bottom-up processes create many theoretical and empirical challenges in the realm of trophic ecology. We propose using specific autecology or species trait (i.e. behavioural) information to help explain and understand trophic dynamics that may involve complicated and non-unidirectional trophic interactions. The common carp (Cyprinus carpio) serve
Authors
Mark A. Kaemingk, Jeffrey C. Jolley, Craig P. Paukert, David W. Willis, Kjetil R. Henderson, Richard S. Holland, Greg A. Wanner, Mark L. Lindvall

Variability in the sensitivity among model simulations of permafrost and carbon dynamics in the permafrost region between 1960 and 2009

A significant portion of the large amount of carbon (C) currently stored in soils of the permafrost region in the Northern Hemisphere has the potential to be emitted as the greenhouse gases CO2and CH4 under a warmer climate. In this study we evaluated the variability in the sensitivity of permafrost and C in recent decades among land surface model simulations over the permafrost region between 196
Authors
A. David McGuire, Charles Koven, David M. Lawrence, Joy S. Clein, Jiangyang Xia, Christian Beer, Eleanor J. Burke, Guangsheng Chen, Xiaodong Chen, Christine Delire, Elchin Jafarov, Andrew H. MacDougall, Sergey S. Marchenko, Dmitry J. Nicolsky, Shushi Peng, Annette Rinke, Kazuyuki Saito, Wenxin Zhang, Ramdane Alkama, Theodore J. Bohn, Philippe Ciais, Bertrand Decharme, Altug Ekici, Isabelle Gouttevin, Tomohiro Hajima, Daniel J. Hayes, Duoying Ji, Gerhard Krinner, Dennis P. Lettenmaier, Yiqi Luo, Paul A. Miller, John C. Moore, Vladimir Romanovsky, Christina Schädel, Kevin Schaefer, Edward A.G. Schuur, Benjamin Smith, Tetsuo Sueyoshi, Qianlai Zhuang

Age, sex and social influences on adult survival in the cooperatively breeding Karoo Scrub-robin

Among cooperatively breeding species, helpers are hypothesised to increase the survival of breeders by reducing breeder workload in offspring care and increased group vigilance against predators. Furthermore, parental nepotism or other benefits of group living may provide a survival benefit to young that delay dispersal to help. We tested these hypotheses in the Karoo Scrub-robin (Cercotrichas cor
Authors
Penn Lloyd, Thomas E. Martin, Andrew Taylor, Anne Braae, Res Altwegg

Large herbivores surf waves of green-up during spring

The green wave hypothesis (GWH) states that migrating animals should track or ‘surf’ high-quality forage at the leading edge of spring green-up. To index such high-quality forage, recent work proposed the instantaneous rate of green-up (IRG), i.e. rate of change in the normalized difference vegetation index over time. Despite this important advancement, no study has tested the assumption that herb
Authors
Jerod Merkle, Kevin L. Monteith, Ellen O. Aikens, Matthew M. Hayes, Kent Hersey, Arthur D. Middleton, Brendan Oates, Hall Sawyer, Brandon Scurlock, Matthew J. Kauffman

Reproduction in moose at their southern range limit

Reproduction is a critical fitness component in large herbivores. Biogeographic models predict that populations occurring at the edges of the range may have compromised reproductive rates because of inferior habitat at range peripheries. When reproductive rates are chronically low, ungulate populations may lack the resiliency to rebound quickly after periods of environmental stress, and this effec
Authors
Joel S. Ruprecht, Kent Hersey, Konrad Hafen, Kevin L. Monteith, Nicholas J. DeCesare, Matthew J. Kauffman, Daniel R. MacNulty

Diet breadth and variability in Sander spp. inferred from stable isotopes

We used stable isotopes of carbon and nitrogen to evaluate trophic similarity between sauger Sander canadensis and walleye S. vitreus in three Missouri River impoundments characterized by unique differences in riverine habitat. Mean δ15N was similar for sauger and walleye in each reservoir ranging from 15.7 to 17.8‰ for sauger and 15.2 to 17.7‰ for walleye. However, mean δ13C was greater for sauge
Authors
M.J. Fincel, Steven R. Chipps, B. D. S. Graeb, M. L. Brown

Hibernal habitat selection by Wood Frogs (Lithobates sylvaticus) in a northern New England montane landscape

Poikilothermic species, such as amphibians, endure harsh winter conditions via freeze-tolerance or freeze-avoidance strategies. Freeze-tolerance requires a suite of complex, physiological mechanisms (e.g., cryoprotectant synthesis); however, behavioral strategies (e.g., hibernal habitat selection) may be used to regulate hibernaculum temperatures and promote overwintering survival. We investigated
Authors
Luke A. Groff, Aram J.K. Calhoun, Cynthia S. Loftin

Validation of a stream and riparian habitat assessment protocol using stream salamanders in the southwest Virginia coalfields

Within the central Appalachia Coalfields, the aquatic impacts of large-scale land uses, such as surface mining, are of particular ecological concern. Identification and quantification of land use impacts to aquatic ecosystems are a necessary first step to aid in mitigation of negative consequences to biota. However, quantifying physical environmental quality such as stream and riparian habitat oft
Authors
Sara E. Sweeten, W. Mark Ford