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: 1308

Invasive hybridization in a threatened species is accelerated by climate change Invasive hybridization in a threatened species is accelerated by climate change

Climate change will decrease worldwide biodiversity through a number of potential pathways1, including invasive hybridization2 (cross-breeding between invasive and native species). How climate warming influences the spread of hybridization and loss of native genomes poses difficult ecological and evolutionary questions with little empirical information to guide conservation management...
Authors
Clint C. Muhlfeld, Ryan P. Kovach, Leslie A. Jones, Robert K. Al-Chokhachy, Matthew C. Boyer, Robb F. Leary, Winsor H. Lowe, Gordon Luikart, Fred W. Allendorf

Influence of whitebark pine decline on fall habitat use and movements of grizzly bears in the Greater Yellowstone Ecosystem Influence of whitebark pine decline on fall habitat use and movements of grizzly bears in the Greater Yellowstone Ecosystem

When abundant, seeds of the high-elevation whitebark pine (WBP; Pinus albicaulis) are an important fall food for grizzly bears (Ursus arctos) in the Greater Yellowstone Ecosystem. Rates of bear mortality and bear/human conflicts have been inversely associated with WBP productivity. Recently, mountain pine beetles (Dendroctonus ponderosae) have killed many cone-producing WBP trees. We...
Authors
Cecily M. Costello, Frank T. van Manen, Mark A. Haroldson, Michael R. Ebinger, Steven L. Cain, Kerry A. Gunther, Daniel D. Bjornlie

Re-evaluation of Yellowstone grizzly bear population dynamics not supported by empirical data: response to Doak & Cutler Re-evaluation of Yellowstone grizzly bear population dynamics not supported by empirical data: response to Doak & Cutler

Doak and Cutler critiqued methods used by the Interagency Grizzly Bear Study Team (IGBST) to estimate grizzly bear population size and trend in the Greater Yellowstone Ecosystem. Here, we focus on the premise, implementation, and interpretation of simulations they used to support their arguments. They argued that population increases documented by IGBST based on females with cubs-of-the...
Authors
Frank T. van Manen, Michael R. Ebinger, Mark A. Haroldson, Richard B. Harris, Megan D. Higgs, Steve Cherry, Gary C. White, Charles C. Schwartz

Parasite-mediated selection drives an immunogenetic tradeoff in plains zebra (Equus quagga) Parasite-mediated selection drives an immunogenetic tradeoff in plains zebra (Equus quagga)

Pathogen evasion of the host immune system is a key force driving extreme polymorphism in genes of the major histocompatibility complex (MHC). Although this gene family is well characterized in structure and function, there is still much debate surrounding the mechanisms by which MHC diversity is selectively maintained. Many studies have investigated relationships between MHC variation...
Authors
Pauline L. Kamath, Wendy C. Turner, Martina Kusters, Wayne M. Getz

Successes and challenges from formation to implementation of eleven broad-extent conservation programs Successes and challenges from formation to implementation of eleven broad-extent conservation programs

Integration of conservation partnerships across geographic, biological, and administrative boundaries is increasingly relevant because drivers of change, such as climate shifts, transcend these boundaries. We explored successes and challenges of established conservation programs that span multiple watersheds and consider both social and ecological concerns. We asked representatives from...
Authors
Erik A. Beever, John B. Bradford, Matthew J. Germino, Brady J. Mattsson, Max Post van der Burg, Mark Brunson

Suppressing bullfrog larvae with carbon dioxide Suppressing bullfrog larvae with carbon dioxide

Current management strategies for the control and suppression of the American Bullfrog (Lithobates catesbeianus = Rana catesbeiana Shaw) and other invasive amphibians have had minimal effect on their abundance and distribution. This study evaluates the effects of carbon dioxide (CO2) on pre- and prometamorphic Bullfrog larvae. Bullfrogs are a model organism for evaluating potential...
Authors
Mark Abbey-Lambert, Andrew Ray, Megan J. Layhee, Christine L. Densmore, Adam Sepulveda, Jackson A. Gross, Barnaby J. Watten

Methods to estimate distribution and range extent of grizzly bears in the Greater Yellowstone Ecosystem Methods to estimate distribution and range extent of grizzly bears in the Greater Yellowstone Ecosystem

The distribution of the Greater Yellowstone Ecosystem grizzly bear ( Ursus arctos) population has expanded into areas unoccupied since the early 20th century. Up-to-date information on the area and extent of this distribution is crucial for federal, state, and tribal wildlife and land managers to make informed decisions regarding grizzly bear management. The most recent estimate of...
Authors
Mark A. Haroldson, Charles C. Schwartz, Daniel J. Thompson, Daniel D. Bjornlie, Kerry A. Gunther, Steven L. Cain, Daniel B. Tyers, Kevin L. Frey, Bryan C. Aber

Testing ecological tradeoffs of a new tool for removing fine sediment in a spring-fed stream 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...
Authors
Adam J. Sepulveda, Juddson D. Sechrist, Laurie B Marczak

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

Aquatic invasive species: Lessons from cancer research 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...
Authors
Adam J. Sepulveda, Andrew Ray, Robert K. Al-Chokhachy, Clint C. Muhlfeld, Robert E. Gresswell, Jackson A. Gross, Jeffrey L. Kershner

Summary of preliminary step-trend analysis from the Interagency Whitebark Pine Long-termMonitoring Program—2004-2013 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...
Authors
Kristin Legg, Erin Shanahan, Rob Daley, Kathryn M. Irvine
Was this page helpful?