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
Discrimination of biological scatterers in polarimetric weather radar data: Opportunities and challenges
For radar aeroecology studies, the identification of the type of scatterer is critically important. Here, we used a random forest (RF) algorithm to develop a variety of scatterer classification models based on the backscatter values in radar resolution volumes of six radar variables (reflectivity, radial velocity, spectrum width, differential reflectivity, correlation coefficient, and differential
Authors
Sidney Gauthreaux, Robert H. Diehl
Revealing migration and reproductive habitat of invasive fish under an active population suppression program
Endemic species face a variety of threats including predation from non‐native invaders. In some cases, however, invasive species can be managed by directly suppressing populations, and tracking technologies that allow researchers to identify movement patterns and aggregations representative of the population can facilitate suppression activities. In Yellowstone Lake (Yellowstone National Park, Wyo
Authors
Lee F. G. Gutowsky, Jason G. Romine, Nicholas A. Heredia, Patricia E. Bigelow, Michael J. Parsley, Philip T. Sandstrom, Cory D. Suski, Andy J. Danylchuk, Steven J. Cooke, Robert E. Gresswell
Alpine plant community diversity in species-area relations at fine scale
Observations of diversity in alpine vegetation appear to be scale dependent. The relations of plant species richness with surface processes and geomorphology have been studied, but patterns of beta diversity are less known. In Glacier National Park, Montana, diversity has been examined within 1 m2 plots and for 16 m2 plots across two ranges, with within-plot and across-range explanatory factors, r
Authors
George P. Malanson, Emma L Nelson, Dale L. Zimmerman, Daniel B. Fagre
Amphibian chytrid prevalence on boreal toads in SE Alaska and NW British Columbia: Tests of habitat, life stages, and temporal trends
Tracking and understanding variation in pathogens such as Batrachochytrium dendrobatidis ([Bd]), which causes amphibian chytridiomycosis and has caused population declines globally, is a priority for many land managers. However, there has been relatively little sampling of amphibian communities at high latitudes. We used skin swabs collected during 2005–2017 from boreal toads (Anaxyrus boreas; N =
Authors
Blake R. Hossack, Michael J. Adams, R Ken Honeycutt, Jami J Belt, S Pyare
A round-robin evaluation of the repeatability and reproducibility of environmental DNA assays for dreissenid mussels
Resource managers may be hesitant to make decisions based on environmental (e)DNA results alone since eDNA is an indirect method of species detection. One way to reduce the uncertainty of eDNA is to identify laboratory‐based protocols that ensure repeatable and reproducible results. We conducted a double‐blind round‐robin analysis of probe‐based assays for DNA of dreissenid (Dreissena spp.) mussel
Authors
Adam J. Sepulveda, Patrick R. Hutchins, Craig Jackson, Carl Ostberg, Matthew Laramie, Jon Amberg, Timothy D. Counihan, Andrew B. Hoegh, David Pilliod
Co-occurence of Chiricahua leopard frogs (Lithobates chiricahuensis) with sunfish (Lepomis)
Invasive species are a major threat to the persistence of native species, particularly in systems where ephemeral aquatic habitats have been replaced by permanent water and predators, such as fish, have been introduced. Within the Altar Valley, Arizona, the invasive American bullfrog, Lithobates catesbeianus (formerly Rana catesbeianus), has been successfully eradicated to help recover Chiricahua
Authors
Paige E. Howell, Brent H. Sigafus, Blake R. Hossack, Erin L. Muths
Contrasting demographic responses of toad populations to regionally synchronous pathogen (Batrachochytrium dendrobatidis) dynamics
Batrachochytrium dendrobatidis (Bd), a fungal pathogen that causes amphibian chytridiomycosis, has been implicated in population declines globally. To better understand how Bd affects survival and how threats vary spatially and temporally, we conducted long-term (range: 9–13 yrs) capture-recapture studies of boreal toads (Anaxyrus boreas) from three similar communities in western Montana. We also
Authors
Blake R. Hossack, Robin E. Russell, Rebecca McCaffery
Primarily resident grizzly bears respond to late-season elk harvest
Autumn ungulate hunting in the Greater Yellowstone Ecosystem carries the risk of hunter–grizzly bear (Ursus arctos) conflict and creates a substantial challenge for managers. For Grand Teton National Park, Wyoming, USA, a key information need is whether increased availability of elk (Cervus canadensis) carcasses during a late autumn (Nov–Dec) harvest within the national park attracts grizzly bears
Authors
Frank T. van Manen, Michael R. Ebinger, David D. Gustine, Mark A. Haroldson, Katharine R. Wilmot, Craig Whitman
Rapid early development and feeding benefits an invasive population of lake trout
Lake trout (Salvelinus namaycush) were discovered in Yellowstone Lake in 1994 and their population expanded dramatically despite intensive suppression. The lake is species-depauperate, with no major lake trout embryo predators. We hypothesized that without this predation threat, lake trout free embryo feeding and growth may be greater than in their native range, leading to increased survival of ag
Authors
Lee G. Simard, J Ellen Marsden, Robert E. Gresswell, Megan Euclide
Whitebark pine (Pinus albicaulis) growth and defense in response to mountain pine beetle outbreaks
Whitebark pine (Pinus albicaulis) is a critical forest species of Northern Rocky Mountain upper subalpine ecosystems, yet little is known about the physiological response of whitebark pine to disturbance (e.g. fire, bark beetles, and pathogens) across a range of diverse environmental gradients. Resin–based defenses have long been recognized as the primary mechanism by which conifers respond to att
Authors
Nickolas E. Kichas, Sharon M. Hood, Gregory T. Pederson, Richard G. Everett, David B. McWethy
Glacier retreat in Glacier National Park, Montana
Currently, the volume of land ice on Earth is decreasing, driving consequential changes to global sea level and local stream habitat. Glacier retreat in Glacier National Park, Montana, U.S.A., is one example of land ice loss and glacier change. The U.S. Geological Survey Benchmark Glacier Project conducts glaciological research and collects field measurements across select North American glaciers,
Authors
Caitlyn Florentine
Parsing the effects of demography, climate, and management on recurrent brucellosis outbreaks in elk
1. Zoonotic pathogens can harm human health and well-being directly or by impacting livestock. Pathogens that spillover from wildlife can also impair conservation efforts if humans perceive wildlife as pests. Brucellosis, caused by the bacterium Brucella abortus, circulates in elk and bison herds of the Greater Yellowstone Ecosystem and poses a risk to cattle and humans. Our goal was to understand
Authors
Gavin G. Cotterill, Paul Cross, Jerod Merkle, JD Rogerson, BM Scurlock, Johan T. Du Toit