Ephemeral stream reaches preserve the evolutionary and distributional history of threespine stickleback in the Santa Clara and Ventura River watersheds of southern California
Jonathan Q. Richmond, David K. Jacobs, Adam R. Backlin, Camm C. Swift, Chris Dellith, Robert N. Fisher
2015, Conservation Genetics (16) 85-101
Much remains to be understood about the evolutionary history and contemporary landscape genetics of unarmored threespine stickleback in southern California, where populations collectively referred to as Gasterosteus aculeatus williamsoni have severely declined over the past 70+ years and are now endangered. We used mitochondrial sequence and microsatellite data to assess...
An open-population hierarchical distance sampling model
Rachel Sollmann, Beth Gardner, Richard B Chandler, J. Andrew Royle, T Scott Sillett
2015, Ecology (96) 325-331
Modeling population dynamics while accounting for imperfect detection is essential to monitoring programs. Distance sampling allows estimating population size while accounting for imperfect detection, but existing methods do not allow for direct estimation of demographic parameters. We develop a model that uses temporal correlation in abundance arising from underlying population...
Evaluation of satellite rainfall estimates for drought and flood monitoring in Mozambique
Carolien Tote, Domingos Patricio, Hendrik Boogaard, Raymond van der Wijngaart, Elena Tarnavsky, Christopher C. Funk
2015, Remote Sensing (7) 1758-1776
Satellite derived rainfall products are useful for drought and flood early warning and overcome the problem of sparse, unevenly distributed and erratic rain gauge observations, provided their accuracy is well known. Mozambique is highly vulnerable to extreme weather events such as major droughts and floods and thus, an understanding of...
Magmatic gas emissions at Holocene volcanic features near Mono Lake, California, and their relation to regional magmatism
D. Bergfeld, William C. Evans, James F. Howle, Andrew G. Hunt
2015, Journal of Volcanology and Geothermal Research (292) 70-83
Silicic lavas have erupted repeatedly in the Mono Basin over the past few thousand years, forming the massive domes and coulees of the Mono Craters chain and the smaller island vents in Mono Lake. We report here on the first systematic study of magmatic CO2 emissions from these features, conducted during...
The cost of reproduction: differential resource specialization in female and male California sea otters
Emma A. Elliott Smith, Seth D. Newsome, James A. Estes, M. Tim Tinker
2015, Oecologia (178) 17-29
Intraspecific variation in behavior and diet can have important consequences for population and ecosystem dynamics. Here, we examine how differences in reproductive investment and spatial ecology influence individual diet specialization in male and female southern sea otters (Enhydra lutris nereis). We hypothesize that greater reproductive constraints and smaller home...
Reducing nitrogen export from the corn belt to the Gulf of Mexico: agricultural strategies for remediating hypoxia
Eileen McLellan, Dale M. Robertson, Keith Schilling, Mark Tomer, Jill Kostel, Douglas G. Smith, Kevin King
2015, Journal of the American Water Resources Association (51) 263-289
SPAtially Referenced Regression on Watershed models developed for the Upper Midwest were used to help evaluate the nitrogen-load reductions likely to be achieved by a variety of agricultural conservation practices in the Upper Mississippi-Ohio River Basin (UMORB) and to compare these reductions to the 45% nitrogen-load reduction proposed to remediate...
In the path of destruction - eyewitness chronicles of Mount St. Helens
Richard B. Waitt
2015, Book
A geologist with intimate knowledge of Mount St. Helens, Richard Waitt chronicles the eruption through unforgettable, riveting narratives—the heart of a masterful chronology that also delivers engrossing science, history, and journalism....
Tectonic activity as a significant source of crustal tetrafluoromethane emissions to the atmosphere: observations in groundwaters along the San Andreas Fault
Daniel A. Deeds, Justin T. Kulongoski, Jens Muhle, Ray F. Weiss
2015, Earth and Planetary Science Letters (412) 163-172
Tetrafluoromethane (CF4) concentrations were measured in 14 groundwater samples from the Cuyama Valley, Mil Potrero and Cuddy Valley aquifers along the Big Bend section of the San Andreas Fault System (SAFS) in California to assess whether tectonic activity in this region is a significant source of crustal CF4 to the...
Factors influencing CO2 and CH4 emissions from coastal wetlands in the Liaohe Delta, northeast China
Linda Olsson, Siyuan Ye, Xueyang Yu, Mengjie Wei, Ken W. Krauss, Hans Brix
2015, Biogeosciences Discussions (12) 3469-3503
Many factors are known to influence greenhouse gas emissions from coastal wetlands, but it is still unclear which factors are most important under field conditions when they are all acting simultaneously. The objective of this study was to assess the effects of water table, salinity, soil temperature and vegetation on...
Advancing the science of microbial symbiosis to support invasive species management: a case study on Phragmites in the Great Lakes
Kurt P. Kowalski, Charles W. Bacon, Wesley A. Bickford, Heather A. Braun, Keith Clay, Michele Leduc-Lapierre, Elizabeth Lillard, Melissa K. McCormick, Eric Nelson, Monica Torres, James W. C. White, Douglas A. Wilcox
2015, Frontiers in Microbiology (6)
A growing body of literature supports microbial symbiosis as a foundational principle for the competitive success of invasive plant species. Further exploration of the relationships between invasive species and their associated microbiomes, as well as the interactions with the microbiomes of native species, can lead to key new insights into...
Nest visits and capture events affect breeding success of Yellow-billed and Pacific loons
Brian D. Uher-Koch, Joel A. Schmutz, Kenneth G. Wright
2015, Condor (7) 121-129
Accurate estimates of breeding success are essential for understanding population dynamics and for managing populations. Unfortunately, research activities to collect these data can negatively impact the breeding success of the study species and bias estimates of breeding success. Despite the potential for negative impacts, few studies have documented the effect...
Preliminary evaluation of an in vivo fluorometer to quantify algal periphyton biomass and community composition
Theodore D. Harris, Jennifer L. Graham
2015, Lake and Reservoir Management (31) 127-133
The bbe-Moldaenke BenthoTorch (BT) is an in vivo fluorometer designed to quantify algal biomass and community composition in benthic environments. The BT quantifies total algal biomass via chlorophyll a (Chl-a) concentration and may differentiate among cyanobacteria, green algae, and diatoms based on pigment fluorescence. To evaluate how BT measurements of...
Mineral Resource of the Month: Antimony
David E. Guberman
2015, Earth Magazine (February 2015)
Antimony is a lustrous silvery-white semimetal or metalloid. Archaeological and historical studies indicate that antimony and its mineral sulfides have been used by humans for at least six millennia. The alchemist Basil Valentine is sometimes credited with “discovering” the element; he described the extraction of metallic antimony from stibnite in...
Flow cytometric method for measuring chromatin fragmentation in fixed sperm from yellow perch (Perca flavescens)
Jill A. Jenkins, Rassa O. Draugelis-Dale, Alfred E. Pinkney, Luke R. Iwanowicz, Vicki Blazer
2015, Theriogenology (83) 920-931
Declining harvests of yellow perch, Perca flavescens, in urbanized watersheds of Chesapeake Bay have prompted investigations of their reproductive fitness. The purpose of this study was to establish a flow cytometric technique for DNA analysis of fixed samples sent from the field to provide reliable gamete quality measurements. Similar to the...
Vegetation burn severity mapping using Landsat-8 and WorldView-2
Zhuoting Wu, Barry R. Middleton, Robert Hetzler, John M. Vogel, Dennis G. Dye
2015, Photogrammetric Engineering and Remote Sensing (2) 143-154
We used remotely sensed data from the Landsat-8 and WorldView-2 satellites to estimate vegetation burn severity of the Creek Fire on the San Carlos Apache Reservation, where wildfire occurrences affect the Tribe's crucial livestock and logging industries. Accurate pre- and post-fire canopy maps at high (0.5-meter) resolution were created from...
Genomics and introgression: Discovery and mapping of thousands of species-diagnostic SNPs using RAD sequencing
Brian K. Hand, Tyler D Hether, Ryan P. Kovach, Clint C. Muhlfeld, Stephen J. Amish, Matthew C. Boyer, Sean M. O’Rourke, Michael R. Miller, Winsor H. Lowe, Paul A. Hohenlohe, Gordon Luikart
2015, Current Zoology (61) 146-154
Invasive hybridization and introgression pose a serious threat to the persistence of many native species. Understanding the effects of hybridization on native populations (e.g., fitness consequences) requires numerous species-diagnostic loci distributed genome-wide. Here we used RAD sequencing to discover thousands of single-nucleotide polymorphisms (SNPs) that are diagnostic between rainbow trout...
Time scales of porphyry Cu deposit formation: insights from titanium diffusion in quartz
Celestine N. Mercer, Mark H. Reed, Cameron M. Mercer
2015, Economic Geology (110) 587-602
Porphyry dikes and hydrothermal veins from the porphyry Cu-Mo deposit at Butte, Montana, contain multiple generations of quartz that are distinct in scanning electron microscope-cathodoluminescence (SEM-CL) images and in Ti concentrations. A comparison of microprobe trace element profiles and maps to SEM-CL images shows that the concentration of Ti in...
Temperature effects induced by climate change on the growth and consumption by salmonines in Lakes Michigan and Huron
Yu-Chun Kao, Charles P. Madenjian, David B. Bunnell, Brent M. Lofgren, Marjorie Perroud
2015, Environmental Biology of Fishes (98) 1089-1104
We used bioenergetics models to investigate temperature effects induced by climate change on the growth and consumption by Chinook salmon Oncorhynchus tshawytscha, lake trout Salvelinus namaycush, and steelhead O. mykiss in Lakes Michigan and Huron. We updated biological inputs to account for recent changes in the food webs and used temperature inputs in response...
Variations in community exposure to lahar hazards from multiple volcanoes in Washington State (USA)
Angela K. Diefenbach, Nathan J. Wood, John W. Ewert
2015, Journal of Applied Volcanology (4)
Understanding how communities are vulnerable to lahar hazards provides critical input for effective design and implementation of volcano hazard preparedness and mitigation strategies. Past vulnerability assessments have focused largely on hazards posed by a single volcano, even though communities and officials in many parts of the world must plan for...
Vegetation and non-native ungulate monitoring at the Big Island National Wildlife Refuge Complex 2010–2014.
Steven C. Hess, Christina R. Leopold, Steven J. Kendall
2015, Technical Report HCSU-062
The Hakalau Forest Unit (HFU) of Big Island National Wildlife Refuge Complex (BINWRC) has intensively managed feral cattle (Bos taurus) and pigs (Sus scrofa) and monitored non-native ungulate presence and distribution during surveys of all managed areas since 1988. We: 1) provide results from recent ungulate surveys at HFU to...
Differences between main-channel and off-channel food webs in the upper Mississippi River revealed by fatty acid profiles of consumers
James H. Larson, Michelle Bartsch, Steve Gutreuter, Brent C. Knights, Lynn Bartsch, William B. Richardson, Jonathan M. Vallazza, Michael T. Arts
2015, Inland Waters (5) 101-106
Large river systems are often thought to contain a mosaic of patches with different habitat characteristics driven by differences in flow and mixing environments. Off-channel habitats (e.g., backwater areas, secondary channels) can become semi-isolated from main-channel water inputs, leading to the development of distinct biogeochemical environments. Observations of adult bluegill...
Inter-annual and spatial variability of Hamon potential evapotranspiration model coefficients
Gregory J. McCabe, Lauren E. Hay, Andy Bock, Steven L. Markstrom, R. Dwight Atkinson
2015, Journal of Hydrology (521) 389-394
Monthly calibrated values of the Hamon PET coefficient (C) are determined for 109,951 hydrologic response units (HRUs) across the conterminous United States (U.S.). The calibrated coefficient values are determined by matching calculated mean monthly Hamon PET to mean monthly free-water surface evaporation. For most locations and months the calibrated coefficients...
Do shrubs reduce the adverse effects of grazing on soil properties?
David J. Eldridge, Genevieve Beecham, James B. Grace
2015, Ecohydrology (8) 1503-1513
Increases in the density of woody plants are a global phenomenon in drylands, and large aggregations of shrubs, in particular, are regarded as being indicative of dysfunctional ecosystems. There is increasing evidence that overgrazing by livestock reduces ecosystem functions in shrublands, but that shrubs may buffer the negative effects of...
A method for estimating the diffuse attenuation coefficient (KdPAR)from paired temperature sensors
Jordan S. Read, Kevin C. Rose, Luke A. Winslow, Emily K. Read
2015, Limnology and Oceanography: Methods (13) 53-61
A new method for estimating the diffuse attenuation coefficient for photosynthetically active radiation (KdPAR) from paired temperature sensors was derived. We show that during cases where the attenuation of penetrating shortwave solar radiation is the dominant source of temperature changes, time series measurements of water temperatures at multiple depths (z1 and z2)...
Hillslope run-off thresholds with shrink–swell clay soils
Ryan D. Stewart, Majdi R. Abou Najm, David E. Rupp, John W. Lane Jr., Hamil C. Uribe, Jose Luis Arumi, John S. Selker
2015, Hydrological Processes (29) 557-571
Irrigation experiments on 12 instrumented field plots were used to assess the impact of dynamic soil crack networks on infiltration and run-off. During applications of intensity similar to a heavy rainstorm, water was seen being preferentially delivered within the soil profile. However, run-off was not observed until soil water content...
