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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: 1197

Sex-biased gene flow among elk in the greater Yellowstone ecosystem

We quantified patterns of population genetic structure to help understand gene flow among elk populations across the Greater Yellowstone Ecosystem. We sequenced 596 base pairs of the mitochondrial control region of 380 elk from eight populations. Analysis revealed high mitochondrial DNA variation within populations, averaging 13.0 haplotypes with high mean gene diversity (0.85). The genetic differ
Authors
Brian K. Hand, Shanyuan Chen, Neil Anderson, Albano Beja-Pereira, Paul C. Cross, Michael R. Ebinger, Hank Edwards, Robert A. Garrott, Marty D. Kardos, Matthew J. Kauffman, Erin L. Landguth, Arthur Middleton, Brandon M. Scurlock, P.J. White, Pete Zager, Michael K. Schwartz, Gordon Luikart

Anaxyrus boreas (western toad) predation

No abstract available.
Authors
Swartz Leah K, Faurot-Daniels Cayley R, Blake R. Hossack, Erin L. Muths

Quantifying the effectiveness of conservation measures to control the spread of anthropogenic hybridization in stream salmonids: A climate adaptation case study

Quantifying the effectiveness of management actions to mitigate the effects of changing climatic conditions (i.e., climate adaptation) can be difficult, yet critical for conservation. We used population genetic data from 1984 to 2011 to assess the degree to which ambient climatic conditions and targeted suppression of sources of nonnative Rainbow Trout Oncorhynchus mykiss have influenced the sprea
Authors
Robert K. Al-Chokhachy, Clint C. Muhlfeld, Matthew Boyer, Leslie A. Jones, Amber Steed, Jeffrey L. Kershner

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 decisions3.
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

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 used fall (15
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

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-year were
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)

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 and specifi
Authors
Pauline L. Kamath, Wendy C. Turner, Martina Küsters, Wayne M. Getz

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 a diverse
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

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 suppression age
Authors
Mark Abbey-Lambert, Andrew Ray, Megan J. Layhee, Christine L. Densmore, Adam J. Sepulveda, Jackson A. Gross, Barnaby J. Watten

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 grizzly bear dis
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

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