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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: 1216

Aquatic invasive species: Lessons from cancer research

Aquatic invasive species are disrupting ecosystems with increasing frequency. Successful control of these invasions has been rare: Biologists and managers have few tools for fighting aquatic invaders. In contrast, the medical community has long worked to develop tools for preventing and fighting cancer. Its successes are marked by a coordinated research approach with multiple steps: prevention, ea
Authors
Adam J. Sepulveda, Andrew Ray, Robert K. Al-Chokhachy, Clint C. Muhlfeld, Robert E. Gresswell, Jackson A. Gross, Jeffrey L. Kershner

Dietary breadth of grizzly bears in the Greater Yellowstone Ecosystem

Grizzly bears (Ursus arctos) in the Greater Yellowstone Ecosystem (GYE) are opportunistic omnivores that eat a great diversity of plant and animal species. Changes in climate may affect regional vegetation, hydrology, insects, and fire regimes, likely influencing the abundance, range, and elevational distribution of the plants and animals consumed by GYE grizzly bears. Determining the dietary brea
Authors
Kerry A. Gunther, Rebecca Shoemaker, Kevin L. Frey, Mark A. Haroldson, Steven L. Cain, Frank T. van Manen, Jennifer K. Fortin

Incorporating probabilistic seasonal climate forecasts into river management using a risk-based framework

[1] Despite the influence of hydroclimate on river ecosystems, most efforts to date have focused on using climate information to predict streamflow for water supply. However, as water demands intensify and river systems are increasingly stressed, research is needed to explicitly integrate climate into streamflow forecasts that are relevant to river ecosystem management. To this end, we present a f
Authors
Richard S. Sojda, Erin Towler, Mike Roberts, Balaji Rajagopalan

Black bear density in Glacier National Park, Montana

We report the first abundance and density estimates for American black bears (Ursus americanus) in Glacier National Park (NP),Montana, USA.We used data from 2 independent and concurrent noninvasive genetic sampling methods—hair traps and bear rubs—collected during 2004 to generate individual black bear encounter histories for use in closed population mark–recapture models. We improved the precisio
Authors
Jeff B. Stetz, Katherine C. Kendall, Amy C. Macleod

Thermal tolerance of meltwater stonefly Lednia tumana nymphs from an alpine stream in Waterton–Glacier International Peace Park, Montana, USA

Global climate change threatens to affect negatively the structure, function, and diversity of aquatic ecosystems worldwide. In alpine systems, the thermal tolerances of stream invertebrates can be assessed to understand better the potential effects of rising ambient temperatures and continued loss of glaciers and snowpack on alpine stream ecosystems. We measured the critical thermal maximum (CTM)
Authors
Hilary G. Billman, J. Joseph Giersch, K.M. Kappenman, Clint C. Muhlfeld, Molly A. H. Webb

The population history of endogenous retroviruses in mule deer (Odocoileus heminous)

Mobile elements are powerful agents of genomic evolution and can be exceptionally informative markers for investigating species and population-level evolutionary history. While several studies have utilized retrotransposon-based insertional polymorphisms to resolve phylogenies, few population studies exist outside of humans. Endogenous retroviruses are LTR-retrotransposons derived from retroviruse
Authors
Pauline L. Kamath, Daniel Elleder, Le Bao, Paul C. Cross, John H. Powell, Mary Poss

Response of Yellowstone grizzly bears to changes in food resources: A synthesis. Final report to the Interagency Grizzly Bear Committee and Yellowstone Ecosystem Subcommittee

The Yellowstone grizzly bear (Ursus arctos) was listed as a threatened species in 1975 (Federal Register 40 FR:31734-31736). Since listing, recovery efforts have focused on increasing population size, improving habitat security, managing bear mortalities, and reducing bear-human conflicts. The Interagency Grizzly Bear Committee (IGBC; partnership of federal and state agencies responsible for grizz
Authors
Frank T. van Manen, Cecily M. Costello, Mark A. Haroldson, Daniel D. Bjornlie, Michael R. Ebinger, Kerry A. Gunther, Mary Frances Mahalovich, Daniel J. Thompson, Megan D. Higgs, Kathryn M. Irvine, Kristin Legg, Daniel B. Tyers, Lisa Landenburger, Steven L. Cain, Kevin L. Frey, Bryan C. Aber, Charles C. Schwartz

Insights into the latent multinomial model through mark-resight data on female grizzly bears with cubs-of-the-year

Mark-resight designs for estimation of population abundance are common and attractive to researchers. However, inference from such designs is very limited when faced with sparse data, either from a low number of marked animals, a low probability of detection, or both. In the Greater Yellowstone Ecosystem, yearly mark-resight data are collected for female grizzly bears with cubs-of-the-year (FCOY),
Authors
Megan D. Higgs, William A. Link, Gary C. White, Mark A. Haroldson, Daniel D. Bjornlie

Roles of patch characteristics, drought frequency, and restoration in long-term trends of a widespread amphibian

Despite the high profile of amphibian declines and the increasing threat of drought and fragmentation to aquatic ecosystems, few studies have examined long-term rates of change for a single species across a large geographic area. We analyzed growth in annual egg-mass counts of the Columbia spotted frog (Rana luteiventris) across the northwestern United States, an area encompassing 3 genetic clades
Authors
Blake R. Hossack, M. J. Adams, Christopher A. Pearl, Kristine W. Wilson, Evelyn L. Bull, Kristin Lohr, Debra Patla, David S. Pilliod, Jason Jones, Kevin Wheeler, Samuel McKay, P. Stephen Corn

Asian carp behavior in response to static water gun firing

The potential for invasion of Asian carp into the Great Lakes has ecological and socio-economic implications. If they become established, Asian carp are predicted to alter lake ecosystems and impact commercial and recreational fisheries. The Chicago Sanitary and Shipping Canal is an important biological conduit between the Mississippi River Basin, where invasive Asian carp are abundant, and the Gr
Authors
Megan J. Layhee, Jackson A. Gross, Michael J. Parsley, Jason G. Romine, David C. Glover, Cory D. Suski, Tristany L. Wagner, Adam Sepulveda, Robert E. Gresswell

Spatial contexts for temporal variability in alpine vegetation under ongoing climate change

A framework to monitor mountain summit vegetation (The Global Observation Research Initiative in Alpine Environments, GLORIA) was initiated in 1997. GLORIA results should be taken within a regional context of the spatial variability of alpine tundra. Changes observed at GLORIA sites in Glacier National Park, Montana, USA are quantified within the context of the range of variability observed in alp
Authors
George P. Malanson, Daniel B. Fagre

Population-level thermal performance of a cold-water ectotherm is linked to ontogeny and local environmental heterogeneity

Negative effects of global warming are predicted to be most severe for species that occupy a narrow range of temperatures, have limited dispersal abilities or have long generation times. These are characteristics typical of many species that occupy small, cold streams.Habitat use, vulnerabilities and mechanisms for coping with local conditions can differ among populations and ontogenetically withi
Authors
Blake R. Hossack, Windsor H. Lowe, Mariah J. Talbott, P. Stephen Corn, Molly A. H. Webb, Kevin M. Kappenman