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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

Testing ecological tradeoffs of a new tool for removing fine sediment in a spring-fed stream

Excessive fine sediment is a focus of stream restoration work because it can impair the structure and function of streams, but few methods exist for removing sediment in spring-fed streams. We tested a novel method of sediment removal with the potential to have minimal adverse effects on the biological community during the restoration process. The Sand Wand system, a dredgeless vacuum developed by
Authors
Adam J. Sepulveda, Juddson D. Sechrist, Laurie B Marczak

Contrasting past and current numbers of bears visiting Yellowstone cutthroat trout streams

Spawning cutthroat trout (Oncorhynchus clarkii bouvieri) were historically abundant within tributary streams of Yellowstone Lake within Yellowstone National Park and were a highly digestible source of energy and protein for Yellowstone’s grizzly bears (Ursus arctos) and black bears (U. americanus). The cutthroat trout population has subsequently declined since the introduction of non-native lake t
Authors
Mark A. Haroldson, Charles C. Schwartz, Justin E. Teisberg, Kerry A. Gunther, Jennifer K. Fortin, Charles T. Robbins

Yellowstone grizzly bear investigations—Annual report of the Interagency Grizzly Bear Study Team 2013

This Annual Report summarizes results of grizzly bear (Ursus arctos) monitoring and research conducted in the Greater Yellowstone Ecosystem (GYE) by the Interagency Grizzly Bear Study Team (IGBST) during 2013. The report also contains a summary of nuisance grizzly bear management actions. 

Summary of preliminary step-trend analysis from the Interagency Whitebark Pine Long-termMonitoring Program—2004-2013

In mixed and dominant stands, whitebark pine (Pinus albicaulis) occurs in over two million acres within the six national forests and two national parks that comprise the Greater Yellowstone Ecosystem (GYE). Currently, whitebark pine, an ecologically important species, is impacted by multiple ecological disturbances; white pine blister rust (Cronartium ribicola), mountain pine beetle (Dendroctonus
Authors
Kristin Legg, Erin Shanahan, Rob Daley, Kathryn M. Irvine

Statistical assessment on a combined analysis of GRYN-ROMN-UCBN upland vegetation vital signs

As of 2013, Rocky Mountain and Upper Columbia Basin Inventory and Monitoring Networks have multiple years of vegetation data and Greater Yellowstone Network has three years of vegetation data and monitoring is ongoing in all three networks. Our primary objective is to assess whether a combined analysis of these data aimed at exploring correlations with climate and weather data is feasible. We summ
Authors
Kathryn M. Irvine, Thomas J. Rodhouse

Meteorological variables associated with deep slab avalanches on persistent weak layers

Deep slab avalanches are a particularly challenging avalanche forecasting problem. These avalanches are typically difficult to trigger, yet when they are triggered they tend to propagate far and result in large and destructive avalanches. For this work we define deep slab avalanches as those that fail on persistent weak layers deeper than 0.9m (3 feet), and that occur after February 1st. We utiliz
Authors
Alex Marienthal, Jordy Hendrikx, Karl Birkeland, Kathryn M. Irvine

Status of whitebarkpine in the Greater Yellowstone Ecosystem: A step-trend analysis comparing 2004-2007 to 2008-2011

Whitebark pine (Pinus albicaulis) is a foundation and keystone species in upper subalpine environments of the northern Rocky Mountains that strongly influences the biodiversity and productivity of high-elevation ecosystems (Tomback et al. 2001, Ellison et al. 2005). Throughout its historic range, whitebark pine has decreased significantly as a major component of high-elevation forests. As a result
Authors
Erin Shanahan, Kathryn M. Irvine, Dave Roberts, Andrea R. Litt, Kristin Legg, Rob Daley, Nina Chambers

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