Increased land use by Chukchi Sea polar bears in relation to changing sea ice conditions
Karyn D. Rode, Ryan H. Wilson, Eric V. Regehr, Michelle St. Martin, David C. Douglas, Jay Olson
2015, PLoS ONE (10)
Recent observations suggest that polar bears (Ursus maritimus) are increasingly using land habitats in some parts of their range, where they have minimal access to their preferred prey, likely in response to loss of their sea ice habitat associated with climatic warming. We used location data from female polar bears...
Evaluation of the U.S. Geological Survey standard elevation products in a two-dimensional hydraulic modeling application for a low relief coastal floodplain
Emitt C. Witt III
2015, Journal of Hydrology (531) 759-767
Growing use of two-dimensional (2-D) hydraulic models has created a need for high resolution data to support flood volume estimates, floodplain specific engineering data, and accurate flood inundation scenarios. Elevation data are a critical input to these models that guide the flood-wave across the landscape allowing the computation of valuable...
Probabilistic 3-D time-lapse inversion of magnetotelluric data: Application to an enhanced geothermal system
Marina Rosas-Carbajal, Nicolas Linde, Jared R. Peacock, F. I. Zyserman, Thomas Kalscheuer, Stephan Thiel
2015, Geophysical Journal International (203) 1946-1960
Surface-based monitoring of mass transfer caused by injections and extractions in deep boreholes is crucial to maximize oil, gas and geothermal production. Inductive electromagnetic methods, such as magnetotellurics, are appealing for these applications due to their large penetration depths and sensitivity to changes in fluid conductivity and fracture connectivity. In...
Validation of mercury tip-switch and accelerometer activity sensors for identifying resting and active behavior in bears
Jasmine Ware, Karyn D. Rode, Anthony M. Pagano, Jeffrey F. Bromaghin, Charles T. Robbins, Joy Erlenbach, Shannon Jensen, Amy Cutting, Nicole Nicassio-Hiskey, Amy Hash, Megan A. Owen, Heiko Jansen
2015, Ursus (26) 8-18
Activity sensors are often included in wildlife transmitters and can provide information on the behavior and activity patterns of animals remotely. However, interpreting activity-sensor data relative to animal behavior can be difficult if animals cannot be continuously observed. In this study, we examined the performance of a mercury tip-switch and...
Alpine biodiversity and assisted migration: The case of the American pika (Ochotona princeps)
Jennifer L. Wilkening, Chris Ray, Nathan G. Ramsay, Kelly Klingler
2015, Biodiversity (16) 1-13
Alpine mammals are predicted to be among the species most threatened by climate change, due to the projected loss and further fragmentation of alpine habitats. As temperature or precipitation regimes change, alpine mammals may also be faced with insurmountable barriers to dispersal. The slow rate or inability to adjust to...
White-tailed Deer (Odocoileus virginianus) fawn risk from Gray Wolf (Canis lupus) predation during summer
L. David Mech, Aaron Morris, Shannon M. Barber-Meyer
2015, Canadian Field-Naturalist (129) 368-373
Little is known about how often various prey animals are at risk of predation by Gray Wolves (Canis lupus). We used a system to monitor the presence during the day of two radio-collared Gray Wolves within 2 km of a radio-collared White-tailed Deer (Odocoileus virginianus) with a fawn or fawns...
On the prediction of threshold friction velocity of wind erosion using soil reflectance spectroscopy
Junran Li, Cody B. Flagg, Gregory S. Okin, Thomas H. Painter, Kebonye Dintwe, Jayne Belnap
2015, Aeolian Research (19) 129-136
Current approaches to estimate threshold friction velocity (TFV) of soil particle movement, including both experimental and empirical methods, suffer from various disadvantages, and they are particularly not effective to estimate TFVs at regional to global scales. Reflectance spectroscopy has been widely used to obtain TFV-related soil properties (e.g., moisture, texture,...
Western water and climate change
Michael D. Dettinger, Bradley Udall, Aris P. Georgakakos
2015, Ecological Applications (25) 2069-2093
The western United States is a region long defined by water challenges. Climate change adds to those historical challenges, but does not, for the most part, introduce entirely new challenges; rather climate change is likely to stress water supplies and resources already in many cases stretched to, or beyond, natural...
A practical guide to the use of major elements, trace elements, and isotopes in compositional data analysis: Applications for deep formation brine geochemistry
Madalyn S. Blondes, Mark A. Engle, Nicholas Geboy
2015, Conference Paper, Proceedings of the International Workshop on Compositional Data Analysis
In the geosciences, isotopic ratios and trace element concentrations are often used along with major element concentrations to help determine sources of and processes affecting geochemical variation. Compositional Data Analysis (CoDA) is a set of tools, generally attuned to major element data, concerned with the proper statistical treatment and removal...
Current land bird distribution and trends in population abundance between 1982 and 2012 on Rota, Mariana Islands
Richard J. Camp, Kevin W. Brinck, P. Marcos Gorresen, Fred A. Amidon, Paul M. Radley, S. Paul Berkowitz, Paul C. Banko
2015, Journal of Fish and Wildlife Management (6) 511-540
The western Pacific island of Rota is the fourth largest human-inhabited island in the Mariana archipelago and designated an Endemic Bird Area. Between 1982 and 2012, 12 point-transect distance-sampling surveys were conducted to assess bird population status. Surveys did not consistently sample the entire island; thus, we used a ratio...
Meteorological variables to aid forecasting deep slab avalanches on persistent weak layers
Alex Marienthal, Jordy Hendrikx, Karl W. Birkeland, Kathryn M. Irvine
2015, Cold Regions Science and Technology (120) 227-236
Deep slab avalanches are particularly challenging to forecast. These avalanches are difficult to trigger, yet when they release they tend to propagate far and can result in large and destructive avalanches. We utilized a 44-year record of avalanche control and meteorological data from Bridger Bowl ski area in southwest Montana...
Assessment of environmental DNA for detecting presence of imperiled aquatic amphibian species in isolated wetlands
Anna M. McKee, Daniel L. Calhoun, William J. Barichivich, Stephen F. Spear, Caren S. Goldberg, Travis C Glenn
2015, Journal of Fish and Wildlife Management (6) 498-510
Environmental DNA (eDNA) is an emerging tool that allows low-impact sampling for aquatic species by isolating DNA from water samples and screening for DNA sequences specific to species of interest. However, researchers have not tested this method in naturally acidic wetlands that provide breeding habitat for a number of imperiled...
Changes in depth occupied by Great Lakes lake whitefish populations and the influence of survey design
Michael D. Rennie, Brian Weidel, Randall M. Claramunt, Erin S. Dunlob
2015, Journal of Great Lakes Research (41) 1150-1161
Understanding fish habitat use is important in determining conditions that ultimately affect fish energetics, growth and reproduction. Great Lakes lake whitefish (Coregonus clupeaformis) have demonstrated dramatic changes in growth and life history traits since the appearance of dreissenid mussels in the Great Lakes, but the role of habitat occupancy in...
Seismic hazard in the Nation's breadbasket
Oliver S. Boyd, Kathleen Haller, Nico Luco, Morgan P. Moschetti, Charles Mueller, Mark D. Petersen, Sanaz Rezaeian, Justin L. Rubinstein
2015, Earthquake Spectra (S1) 109-130
The USGS National Seismic Hazard Maps were updated in 2014 and included several important changes for the central United States (CUS). Background seismicity sources were improved using a new moment-magnitude-based catalog; a new adaptive, nearest-neighbor smoothing kernel was implemented; and maximum magnitudes for background sources were updated. Areal source zones...
Monitoring changes in seismic velocity related to an ongoing rapid inflation event at Okmok volcano, Alaska
Ninfa Bennington, Matthew M. Haney, Silvio De Angelis, Clifford Thurber, Jeff Freymueller
2015, Journal of Geophysical Research (120) 5664-5676
Okmok is one of the most active volcanoes in the Aleutian Arc. In an effort to improve our ability to detect precursory activity leading to eruption at Okmok, we monitor a recent, and possibly ongoing, GPS-inferred rapid inflation event at the volcano using ambient noise interferometry (ANI). Applying this method,...
Hybridization between Dusky Grouse and Sharp-tailed Grouse
Ryan P. O’Donnell
2015, Western Birds (46) 351-352
Cache County, Utah, 7 April 2013: rare hybrid combination of grouse noted. Hybridization between Dusky Grouse (Dendragapus obscurus) and Sharp-tailed Grouse (Tympanuchus phasianellus) has been rarely documented in the wild. The only published record was of one collected from Osoyoos, British Columbia, in 1906 (Brooks 1907, Lincoln 1950). There is...
Why are freshwater fish so threatened?
Gerard P. Closs, Paul L. Angermeier, William R.T. Darwall, Stephen R. Balcombe
2015, Book chapter, Conservation of Freshwater Fishes
The huge diversity of freshwater fishes is concentrated into an area of habitat that covers only about 1% of the Earth's surface, and much of this limited area has already been extensively impacted and intensively managed to meet human needs (Dudgeon et al., 2006). As outlined in Chapter 1, the number...
Management and the conservation of freshwater ecosystems
Mark S. Wipfli, John S. Richardson
2015, Book chapter
Riparian areas are the terrestrial environment adjacent to water that both influences and is influenced by the aquatic feature (Gregory et al., 1991; Naiman et al., 2010). Riparian areas along streams provide shade, sources of wood and organic matter, contribute to bank stability, filter sediments, take up excess nutrients from groundwater inputs,...
The 2014 update to the National Seismic Hazard Model in California
Peter M. Powers, Edward H. Field
2015, Earthquake Spectra (31) S177-S200
The 2014 update to the U. S. Geological Survey National Seismic Hazard Model in California introduces a new earthquake rate model and new ground motion models (GMMs) that give rise to numerous changes to seismic hazard throughout the state. The updated earthquake rate model is the third version of the...
The 2014 United States National Seismic Hazard Model
Mark D. Petersen, Morgan P. Moschetti, Peter M. Powers, Charles Mueller, Kathleen Haller, Arthur D. Frankel, Yuehua Zeng, Sanaz Rezaeian, Stephen Harmsen, Oliver S. Boyd, Edward H. Field, Rui Chen, Kenneth S. Rukstales, Nico Luco, Russell Wheeler, Robert Williams, Anna H. Olsen
2015, Earthquake Spectra (31) S1-S30
New seismic hazard maps have been developed for the conterminous United States using the latest data, models, and methods available for assessing earthquake hazard. The hazard models incorporate new information on earthquake rupture behavior observed in recent earthquakes; fault studies that use both geologic and geodetic strain rate data; earthquake...
Hydrologic implications of GRACE satellite data in the Colorado River Basin
Bridget R. Scanlon, Zizhan Zhang, Robert C. Reedy, Donald R. Pool, Himanshu Save, Di Long, Jianli Chen, David M. Wolock, Brian D. Conway, Daniel Winester
2015, Water Resources Research (51) 9891-9903
Use of GRACE (Gravity Recovery and Climate Experiment) satellites for assessing global water resources is rapidly expanding. Here we advance application of GRACE satellites by reconstructing long-term total water storage (TWS) changes from ground-based monitoring and modeling data. We applied the approach to the Colorado River Basin which has experienced...
Determining climate change management priorities: A case study from Wisconsin
Olivia E. LeDee, Christine Ribic
2015, Journal of Conservation Planning (11) 1-12
A burgeoning dialogue exists regarding how to allocate resources to maximize the likelihood of long-term biodiversity conservation within the context of climate change. To make effective decisions in natural resource management, an iterative, collaborative, and learning-based decision process may be more successful than a strictly consultative approach. One important, early...
Combining NLCD and MODIS to create a land cover-albedo database for the continental United States
J. Wickham, Christopher A. Barnes, M.S. Nash, T.G. Wade
2015, Remote Sensing of Environment (170) 143-152
Land surface albedo is an essential climate variable that is tightly linked to land cover, such that specific land cover classes (e.g., deciduous broadleaf forest, cropland) have characteristic albedos. Despite the normative of land-cover class specific albedos, there is considerable variability in albedo within a land cover class. The National...
The nest-concealment hypothesis: New insights from a comparative analysis
Kathi L. Borgmann, Courtney J. Conway
2015, Wilson Journal of Ornithology (127) 646-660
Selection of a breeding site is critical for many animals, especially for birds whose offspring are stationary during development. Thus, birds are often assumed to prefer concealed nest sites. However, 74% of studies (n = 106) that have evaluated this relationship for open-cup nesting songbirds in North America failed to support...
Quantifying the residence time and flushing characteristics of a shallow, back-barrier estuary: Application of hydrodynamic and particle tracking models
Zafer Defne, Neil K. Ganju
2015, Estuaries and Coasts (38) 1719-1734
Estuarine residence time is a major driver of eutrophication and water quality. Barnegat Bay-Little Egg Harbor (BB-LEH), New Jersey, is a lagoonal back-barrier estuary that is subject to anthropogenic pressures including nutrient loading, eutrophication, and subsequent declines in water quality. A combination of hydrodynamic and particle tracking modeling was used...
