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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: 1211

Extending ordinal regression with a latent zero-augmented beta distribution

Ecological abundance data are often recorded on an ordinal scale in which the lowest category represents species absence. One common example is when plant species cover is visually assessedwithin bounded quadrats and then assigned to pre-defined cover class categories.We present an ordinal beta hurdle model that directly models ordinal category probabilitieswith a biologically realistic beta-distr
Authors
Kathryn M. Irvine, T.J. Rodhouse, Ilai. N. Keren

Effects of energy development on wetland plants and macroinvertebrate communities in Prairie Pothole Region wetlands

Energy production in the Williston Basin, USA, results in the coproduction of highly saline, sodium chloride-dominated water (brine). The Prairie Pothole Region (PPR) overlies the northeastern portion of the Williston Basin. Although PPR wetlands span a range of salinity, the dominant salt is sodium sulfate, and salinities are much lower than brine. Introduction of brine to wetlands can result in
Authors
Todd M. Preston, Andrew M. Ray

Demographic mechanisms underpinning genetic assimilation of remnant groups of a large carnivore

Current range expansions of large terrestrial carnivores are occurring following human-induced range contraction. Contractions are often incomplete, leaving small remnant groups in refugia throughout the former range. Little is known about the underlying ecological and evolutionary processes that influence how remnant groups are affected during range expansion. We used data from a spatially explic
Authors
Nathaniel Mikle, Tabitha A. Graves, Ryan P. Kovach, Katherine C. Kendall, Amy C. Macleod

Pika (Ochotona princeps) losses from two isolated regions reflect temperature and water balance, but reflect habitat area in a mainland region

Although biotic responses to contemporary climate change are spatially pervasive and often reflect synergies between climate and other ecological disturbances, the relative importance of climatic factors versus habitat extent for species persistence remains poorly understood. To address this shortcoming, we performed surveys for American pikas (Ochotona princeps) at > 910 locations in 3 geographic
Authors
Erik A. Beever, John D. Perrine, Tom Rickman, Mary Flores, John P. Clark, Cassie Waters, Shana S. Weber, Braden Yardley, David P. Thoma, Tara L. Chesley-Preston, Kenneth E. Goehring, Michael Magnuson, Nancy Nordensten, Melissa Nelson, Gail H. Collins

Disease introduction is associated with a phase transition in bighorn sheep demographics

Ecological theory suggests that pathogens are capable of regulating or limiting host population dynamics, and this relationship has been empirically established in several settings. However, although studies of childhood diseases were integral to the development of disease ecology, few studies show population limitation by a disease affecting juveniles. Here, we present empirical evidence that dis
Authors
Kezia Manlove, E. Frances Cassirer, Paul C. Cross, Raina K. Plowright, Peter J. Hudson

Potential of environmental DNA to evaluate Northern pike (Esox lucius) eradication efforts: An experimental test and case study

Determining the success of invasive species eradication efforts is challenging because populations at very low abundance are difficult to detect. Environmental DNA (eDNA) sampling has recently emerged as a powerful tool for detecting rare aquatic animals; however, detectable fragments of DNA can persist over time despite absence of the targeted taxa and can therefore complicate eDNA sampling after
Authors
Kristine J. Dunker, Adam J. Sepulveda, Robert L. Massengill, Jeffrey B. Olsen, Ora L. Russ, John K. Wenburg, Anton Antonovich

Mechanistic variables can enhance predictive models of endotherm distributions: The American pika under current, past, and future climates

How climate constrains species’ distributions through time and space is an important question in the context of conservation planning for climate change. Despite increasing awareness of the need to incorporate mechanism into species distribution models (SDMs), mechanistic modeling of endotherm distributions remains limited in this literature. Using the American pika (Ochotona princeps) as an examp
Authors
Paul Mathewson, Lucas Moyer-Horner, Erik A. Beever, Natalie Briscoe, Michael T. Kearney, Jeremiah Yahn, Warren P. Porter

Life history characteristics and vital rates of Yellowstone Cutthroat Trout in two headwater basins

The Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri is native to the Rocky Mountains and has declined in abundance and distribution as a result of habitat degradation and introduced salmonid species. Many of its remaining strongholds are in headwater basins with minimal human disturbances. Understanding the life histories, vital rates, and behaviors of Yellowstone Cutthroat Trout within
Authors
Patrick Uthe, Robert K. Al-Chokhachy, Alexander V. Zale, Bradley B. Shepard, Thomas E. McMahon, Tracy Stephens

Distribution of a climate-sensitive species at an interior range margin

Advances in understanding the factors that limit a species’ range, particularly in the context of climate change, have come disproportionately through investigations at range edges or margins. The margins of a species’ range might often correspond with anomalous microclimates that confer habitat suitability where the species would otherwise fail to persist. We addressed this hypothesis using data
Authors
Chris Ray, Erik A. Beever, Thomas J. Rodhouse

Niche shifts and energetic condition of songbirds in response to phenology of food-resource availability in a high-elevation sagebrush ecosystem

Seasonal fluctuations in food availability can affect diets of consumers, which in turn may influence the physiological state of individuals and shape intra- and inter-specific patterns of resource use. High-elevation ecosystems often exhibit a pronounced seasonal “pulse” in productivity, although few studies document how resource use and energetic condition by avian consumers change in relation t
Authors
Kyle A. Cutting, Michelle L. Anderson, Erik A. Beever, Sean Schroff, Nathan Korb, Eric Klaphake, Scott R. McWilliams

A long-term evaluation of biopsy darts and DNA to estimate cougar density

Accurately estimating cougar (Puma concolor) density is usually based on long-term research consisting of intensive capture and Global Positioning System collaring efforts and may cost hundreds of thousands of dollars annually. Because wildlife agency budgets rarely accommodate this approach, most infer cougar density from published literature, rely on short-term studies, or use hunter harvest dat
Authors
Richard A. Beausoleil, Joseph D. Clark, Benjamin T. Maletzke

Evaluating the effectiveness of wildlife detection and observation technologies at a solar power tower facility

Solar power towers produce electrical energy from sunlight at an industrial scale. Little is known about the effects of this technology on flying animals and few methods exist for automatically detecting or observing wildlife at solar towers and other tall anthropogenic structures. Smoking objects are sometimes observed co-occurring with reflected, concentrated light (“solar flux”) in the airspace
Authors
Robert H. Diehl, Ernest W. Valdez, Todd M. Preston, Mike J. Wellik, Paul M. Cryan