Skip to main content
U.S. flag

An official website of the United States government

Publications

Below is a list of available NOROCK peer reviewed and published science. If you are in search of a specific publication and cannot find it below or through a search, please contact twojtowicz@usgs.gov.

Filter Total Items: 1220

Inferential consequences of modeling rather than measuring snow accumulation in studies of animal ecology

Abstract. It is increasingly common for studies of animal ecology to use model-based predictions of environmental variables as explanatory or predictor variables, even though model prediction uncertainty is typically unknown. To demonstrate the potential for misleading inferences when model predictions with error are used in place of direct measurements, we compared snow water equivalent (SWE) and
Authors
Paul C. Cross, Robert W. Klaver, Angela Brennan, Scott Creel, Jon P. Beckmann, Megan D. Higgs, Brandon M. Scurlock

Factors influencing the distribution of native bull trout and westslope cutthroat trout in western Glacier National Park, Montana

The widespread declines of native bull trout (Salvelinus confluentus) and westslope cutthroat trout (Oncorhynchus clarkii lewisi) populations prompted researchers to investigate factors influencing their distribution and status in western Glacier National Park, Montana. We evaluated the association of a suite of abiotic factors (stream width, elevation, gradient, large woody debris density, pool d
Authors
Vincent S. D'Angelo, Clint C. Muhlfeld

Genomic patterns of introgression in rainbow and westslope cutthroat trout illuminated by overlapping paired-end RAD sequencing

Rapid and inexpensive methods for genomewide single nucleotide polymorphism (SNP) discovery and genotyping are urgently needed for population management and conservation. In hybridized populations, genomic techniques that can identify and genotype thousands of species-diagnostic markers would allow precise estimates of population- and individual-level admixture as well as identification of 'super
Authors
Paul A. Hohenlohe, Mitch D. Day, Stephen J. Amish, Michael R. Miller, Nick Kamps-Hughes, Matthew C. Boyer, Clint C. Muhlfeld, Fred W. Allendorf, Eric A. Johnson, Gordon Luikart

Regional patterns and proximal causes of the recent snowpack decline in the Rocky Mountains, U.S.

We used a first-order, monthly snow model and observations to disentangle seasonal influences on 20th century,regional snowpack anomalies in the Rocky Mountains of western North America, where interannual variations in cool-season (November–March) temperatures are broadly synchronous, but precipitation is typically antiphased north to south and uncorrelated with temperature. Over the previous eigh
Authors
Gregory T. Pederson, Julio L. Betancourt, Gregory J. McCabe

Characterizing the thermal suitability of instream habitat for salmonids: A cautionary example from the Rocky Mountains

Understanding a species’ thermal niche is becoming increasingly important for management and conservation within the context of global climate change, yet there have been surprisingly few efforts to compare assessments of a species’ thermal niche across methods. To address this uncertainty, we evaluated the differences in model performance and interpretations of a species’ thermal niche when using
Authors
Robert K. Al-Chokhachy, Seth J. Wegner, Daniel J. Isaak, Jeffrey L. Kershner

Statistical classification of vegetation and water depths in montane wetlands

Relationships between water depths and density of submergent vegetation were studied in montane wetlands using statistical techniques based on clustering and an extension of regression trees. Sago pondweed (Stuckenia pectinata) was associated with lower average water depths than water milfoil (Myriophyllum sibiricum). We detected a nonlinear relationship when average water depths were used to pred
Authors
Julia L. Sharp, Richard S. Sodja, Mark Greenwood, Donald O. Rosenberry, Jeffrey M. Warren

Omnivory and the terrestrial food web: Yellowstone grizzly beard diets

No abstract available.
Authors
Charles C. Schwartz, Mark A. Haroldson, Kerry A. Gunther, Charles T. Robbins

Exotic plant colonization and occupancy within riparian areas of the Interior Columbia River and Upper Missouri River basins, USA

Exotic plant invasions into riparia often result in shifts in vegetative composition, altered stream function, and cascading effects to biota at multiple scales. Characterizing the distribution patterns of exotic plants is an important step in directing targeted research to identify mechanisms of invasion and potential management strategies. In this study, we employed occupancy models to examine t
Authors
Robert K. Al-Chokhachy, Andrew M. Ray, Brett B. Roper, Eric Archer

Interactive effects of wildfire, forest management, and isolation on amphibian and parasite abundance

Projected increases in wildfire and other climate-driven disturbances will affect populations and communities worldwide, including host–parasite relationships. Research in temperate forests has shown that wildfire can negatively affect amphibians, but this research has occurred primarily outside of managed landscapes where interactions with human disturbances could result in additive or synergisti
Authors
Blake R. Hossack, Winsor H. Lowe, R. Ken Honeycutt, Sean A. Parks, P. Stephen Corn

Underestimating the effects of spatial heterogeneity due to individual movement and spatial scale: infectious disease as an example

Many ecological and epidemiological studies occur in systems with mobile individuals and heterogeneous landscapes. Using a simulation model, we show that the accuracy of inferring an underlying biological process from observational data depends on movement and spatial scale of the analysis. As an example, we focused on estimating the relationship between host density and pathogen transmission. Obs
Authors
Paul C. Cross, Damien Caillaud, Dennis M. Heisey

Disease in a dynamic landscape: host behavior and wildfire reduce amphibian chytrid infection

Disturbances are often expected to magnify effects of disease, but these effects may depend on the ecology, behavior, and life history of both hosts and pathogens. In many ecosystems, wildfire is the dominant natural disturbance and thus could directly or indirectly affect dynamics of many diseases. To determine how probability of infection by the aquatic fungus Batrachochytrium dendrobatidis (Bd)
Authors
Blake R. Hossack, Winsor H. Lowe, Joy L. Ware, Paul Stephen Corn

Introduced northern pike predation on salmonids in southcentral Alaska

Northern pike (Esox lucius) are opportunistic predators that can switch to alternative prey species after preferred prey have declined. This trophic adaptability allows invasive pike to have negative effects on aquatic food webs. In Southcentral Alaska, invasive pike are a substantial concern because they have spread to important spawning and rearing habitat for salmonids and are hypothesised to b
Authors
Adam Sepulveda, David S. Rutz, Sam S. Ivey, Kristine J. Dunker, Jackson A. Gross
Was this page helpful?