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: 1308
Agent-based models for collective animal movement: Proximity-induced state switching Agent-based models for collective animal movement: Proximity-induced state switching
Animal movement is a complex phenomenon where individual movement patterns can be influenced by a variety of factors including the animal’s current activity, available terrain and habitat, and locations of other animals. Motivated by modeling grizzly bear movement in the Greater Yellowstone Ecosystem, this article presents an agent-based model represented in a state-space framework for...
Authors
Andrew B. Hoegh, Frank T. van Manen, Mark A. Haroldson
Physiological consequences of consuming low-energy foods: Herbivory coincides with a stress response in Yellowstone bears. Physiological consequences of consuming low-energy foods: Herbivory coincides with a stress response in Yellowstone bears.
Meat, fruit, seeds and other high-energy bear foods are often highly localized and briefly available and understanding which factors influence bear consumption of these foods is a common focus of bear conservation and ecology. However, the most common bear foods, graminoids and forbs, are more widespread but of lower quality. We poorly understand how herbage consumption impacts bear...
Authors
David A Christianson, Tyler H Coleman, Quint Doan, Mark A. Haroldson
U.S. Geological Survey science for the Wyoming Landscape Conservation Initiative—2018 annual report U.S. Geological Survey science for the Wyoming Landscape Conservation Initiative—2018 annual report
The Wyoming Landscape Conservation Initiative (WLCI) was established in 2007 as a collaborative interagency partnership to develop and implement science-based conservation actions. During the past 11 years, partners from U.S. Geological Survey (USGS), State and Federal land management agencies, universities, and the public have collaborated to implement a long-term (more than 10 years)...
Authors
Patrick J. Anderson, Cameron L. Aldridge, Jason S. Alexander, Timothy J. Assal, Steven Aulenbach, Zachary H. Bowen, Anna D. Chalfoun, Geneva W. Chong, Holly Copeland, David R. Edmunds, Steve Germaine, Tabitha A. Graves, Julie A. Heinrichs, Collin G. Homer, Christopher Huber, Aaron N. Johnston, Matthew J. Kauffman, Daniel J. Manier, Ryan R. McShane, Cheryl A. Eddy-Miller, Kirk A. Miller, Adrian P. Monroe, Michael S. O’Donnell, Anna Ortega, Annika W. Walters, Daniel J. Wieferich, Teal B. Wyckoff, Linda Zeigenfuss
Is the grass always greener? Land surface phenology reveals differences in peak and season-long vegetation productivity responses to climate and management Is the grass always greener? Land surface phenology reveals differences in peak and season-long vegetation productivity responses to climate and management
Vegetation phenology—the seasonal timing and duration of vegetative phases—is controlled by spatiotemporally variable contributions of climatic and environmental factors plus additional potential influence from human management. We used land surface phenology derived from the Advanced Very High Resolution Radiometer and climate data to examine variability in vegetation productivity and
Authors
David J. A. Wood, Scott Powell, Paul C. Stoy, Lindsey Thurman, Erik A. Beever
Factors influencing distributional shifts and abundance at the range core of a climate-sensitive mammal Factors influencing distributional shifts and abundance at the range core of a climate-sensitive mammal
Species are frequently responding to contemporary climate change by shifting to higher elevations and poleward to track suitable climate space. However, depending on local conditions and species’ sensitivity, the nature of these shifts can be highly variable and difficult to predict. Here, we examine how the American pika (Ochotona princeps), a philopatric, montane lagomorph, responds to...
Authors
Peter D Billman, Erik A. Beever, Dave B. McWethy, Lindsey Thurman, Kenny C Wilson
Evaluating corticosterone as a biomarker for amphibians exposed to increased salinity and ambient corticosterone Evaluating corticosterone as a biomarker for amphibians exposed to increased salinity and ambient corticosterone
Physiological biomarkers are commonly used to assess the health of taxa exposed to natural and anthropogenic stressors. Glucocorticoid (GC) hormones are often used as indicators of physiological stress in wildlife because they affect growth, reproduction and survival. Increased salinity from human activities negatively influences amphibians and their corticosterone (CORT; the main...
Authors
Brian J. Tornabene, Blake R. Hossack, Erica J Crespi, Creagh W Breuner
Vulnerability of Pacific salmon to invasion of northern pike (Esox lucius) in Southcentral Alaska Vulnerability of Pacific salmon to invasion of northern pike (Esox lucius) in Southcentral Alaska
The relentless role of invasive species in the extinction of native biota requires predictions of ecosystem vulnerability to inform proactive management strategies. The worldwide invasion and range expansion of predatory northern pike (Esox lucius) has been linked to the decline of native fishes and tools are needed to predict the vulnerability of habitats to invasion over broad...
Authors
Chase S. Jalbert, Jeffrey A. Falke, Andres Lopez, Kristine J. Dunker, Adam Sepulveda, Peter A. H. Westley
Metal accumulation varies with life history, size, and development of larval amphibians Metal accumulation varies with life history, size, and development of larval amphibians
Amphibian larvae are commonly used as indicators of aquatic ecosystem health because they are susceptible to contaminants. However, there is limited information on how species characteristics and trophic position influence contaminant loads in larval amphibians. Importantly, there remains a need to understand whether grazers (frogs and toads [anurans]) and predators (salamanders) provide
Authors
Kelly L. Smalling, Emily Bea Oja, Danielle M. Cleveland, Jon D Davenport, Collin A. Eagles-Smith, Evan H. Campbell Grant, Patrick M. Kleeman, Brian J. Halstead, Kenzi M Stemp, Brian J. Tornabene, Zachary J Bunnell, Blake R. Hossack
Resilience to fire and resistance to annual grass invasion in sagebrush ecosystems of US National Parks Resilience to fire and resistance to annual grass invasion in sagebrush ecosystems of US National Parks
Western North American sagebrush shrublands and steppe face accelerating risks from fire-driven feedback loops that transition these ecosystems into self-reinforcing states dominated by invasive annual grasses. In response, sagebrush conservation decision-making is increasingly done through the lens of resilience to fire and annual grass invasion resistance. Operationalizing resilience...
Authors
Thomas Rodhouse, Jeffrey Lonneker, Lisa Bowersock, Diana Popp, Jamela Thompson, Gordon Dicus, Kathryn M. Irvine
Spatial Gaussian processes improve multi-species occupancy models when range boundaries are uncertain and nonoverlapping Spatial Gaussian processes improve multi-species occupancy models when range boundaries are uncertain and nonoverlapping
Species distribution models enable practitioners to analyze large datasets of encounter records and make predictions about species occurrence at unsurveyed locations. In omnibus surveys that record data on multiple species simultaneously, species ranges are often nonoverlapping and misaligned with the administrative unit defining the spatial domain of interest (e.g., a state or province)
Authors
Wilson Wright, Kathryn M. Irvine, Tom Rodhouse, Andrea R. Litt
Greater Yellowstone climate assessment: Past, present, and future climate change in the greater Yellowstone watersheds Greater Yellowstone climate assessment: Past, present, and future climate change in the greater Yellowstone watersheds
The Greater Yellowstone Area (GYA) is one of the last remaining large and nearly intact temperate ecosystems on Earth. GYA was originally defined in the 1970s as the Greater Yellowstone Ecosystem, which encompassed the minimum range of the grizzly bear. The boundary now includes about 22 million acres (8.9 million ha) in northwestern Wyoming, south central Montana, and eastern Idaho...
Authors
Steven W. Hostetler, Cathy Whitlock, Bryan Shuman, David Liefert, Charles Wolf Drimal, Scott Bischke
Integration of geophysical evidence suggests that anorthosite composes a significant portion of Grand Marais ridge, an inferred basement high in western Lake Superior Integration of geophysical evidence suggests that anorthosite composes a significant portion of Grand Marais ridge, an inferred basement high in western Lake Superior
The Midcontinent Rift System (MRS) is expressed geophysically by a semi-linear, regional gravity high that trends across the Midcontinent and Great Lakes region of North America. The gravity high is interrupted by two prominent, semi-circular gravity lows, which have been interpreted from modeling and seismic-reflection sections as basement highs of Archean granite (Allen et al., 1997)...
Authors
V. J. Grauch, Samuel J. Heller