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Consequences Of The Megafauna Extinction: Changes In Food Web Networks On The Edwards Plateau Across The Pleistocene-Holocene Transition, Quentin A. Smith Jr.

School of Biological Sciences: Dissertations, Theses, and Student Research

We are experiencing biodiversity loss due to climate change and human impacts, which is not only harmful to the environment but can also alter the composition of communities and interactions among species. The late Pleistocene experienced a loss of large-bodied mammals which resulted in significant changes in community structure due to changes in body size, diet, and species associations. The impact of these changes on species interactions and community structure across the Pleistocene-Holocene transition remains poorly understood. Using a robust data set of species composition, stable isotopes, body size, and climate variables, we constructed and compared ecological networks of mammal …

The Association Between Drought Exposure And Respiratory-Related Mortality In The United States From 2000 To 2018, Yeongjin Gwon, Yuanyuan Ji, Jesse E. Bell, Azar M. Abadi, Jesse D. Berman, Austin Rau, Ronald D. Leeper, Jared Rennie

Daugherty Water for Food Global Institute: Faculty Publications

Climate change has brought increasing attention to the assessment of health risks associated with climate and extreme events. Drought is a complex climate phenomenon that has been increasing in frequency and severity both locally and globally due to climate change. However, the health risks of drought are often overlooked, especially in places such as the United States, as the pathways to health impacts are complex and indirect. This study aims to conduct a comprehensive assessment of the effects of monthly drought exposure on respiratory mortality for NOAA climate regions in the United States from 2000 to 2018. A two-stage model …

Role Of Social Determinants Of Health In Differential Respiratory Exposure And Health Outcomes Among Children, Jagadeesh Puvvula, Jill A. Poole, Yeongjin Gwon, Eleanor G. Rogan, Jesse E. Bell

Daugherty Water for Food Global Institute: Faculty Publications

Background Attributes defining the Social Determinants of Health (SDoH) are associated with disproportionate exposures to environmental hazards and differential health outcomes among communities. The dynamics between SDoH, disproportionate environmental exposures, and differential health outcomes are often specific to micro-geographic areas.

Methods This study focused on children less than 20 years of age who lived in Douglas County, Nebraska, during 2016–2019. To assess the role of SDoH in differential exposures, we evaluated the association between SDoH metrics and criteria pollutant concentrations and the association between SDoH and pediatric asthma exacerbations to quantify the role of SDoH in differential pediatric asthma outcomes. …

Limited Rigor In Studies Of Raptor Mortality And Mitigation At Wind Power Facilities, Tara J. Conkling, Christopher J.W. Mcclure, Sandra Cuadros, Scott R. Loss, Todd E. Katzner

United States Geological Survey: Staff Publications

Wind power is an expanding source of renewable energy. However, there are ecological challenges related to wind energy generation, including collisions of wildlife with turbines. Lack of rigor, and variation in study design, together limit efforts to understand the broad-scale effects of wind power infrastructure on wildlife populations. It is not clear, however, whether these types of limitations apply to groups of birds such as raptors that are particularly vulnerable to negative effects of wind energy. We reviewed 672 peer-reviewed publications, unpublished reports, and citations from 321 wind facilities in 12 countries to evaluate methods used to monitor and mitigate …

Exploiting Common Senses: Sensory Ecology Meets Wildlife Conservation And Management, Laura K. Elmer, Christine L. Madliger, Daniel T. Blumstein, Chris K. Elvidge, Esteban Ernández-Juricic, Andrij Z. Horodysky, Nicholas S. Johnson, Liam P. Mcguire, Ronald R. Swaisgood, Steven J. Cooke

United States Geological Survey: Staff Publications

Multidisciplinary approaches to conservation and wildlife management are often effective in addressing complex, multi-factor problems. Emerging fields such as conservation physiology and conservation behaviour can provide innovative solutions and management strategies for target species and systems. Sensory ecology combines the study of ‘how animals acquire’ and process sensory stimuli from their environments, and the ecological and evolutionary significance of ‘how animals respond’ to this information. We review the benefits that sensory ecology can bring to wildlife conservation and management by discussing case studies across major taxa and sensory modalities. Conservation practices informed by a sensory ecology approach include the amelioration …

Traffic Noise And Sexual Selection: Studies Of Anthropogenic Impact On Bird Songs And Undergraduate Student Reasoning Of Evolutionary Mechanisms, Sarah Spier

School of Natural Resources: Dissertations, Theses, and Student Research

Humans have transformed much of the natural landscape and are continuing to do so at an accelerated rate, compromising natural areas that serve as important habitat for many species. Roads impact much of the environment as they fragment habitat and introduce traffic noise into the acoustic environment, deferentially affecting wildlife in roadside habitat. I explored how traffic noise affects the detection of birds based on whether their vocalizations were masked by traffic noise. Masked species detection was not affected by an increase in traffic noise amplitude, while there was a negative effect of traffic noise amplitude on unmasked species detection, …

Monitoring Spatial And Temporal Variabilities Of Gross Primary Production Using Maiac Modis Data, Marcos Fernandez-Martinez, Rong Yu, John Gamon, Gabriel Hmimina, Iolanda Filella, Manuela Balzarolo, Benjamin Stocker, Josep Penuelas

Center for Advanced Land Management Information Technologies: Publications

Remotely sensed vegetation indices (RSVIs) can be used to efficiently estimate terrestrial primary productivity across space and time. Terrestrial productivity, however, has many facets (e.g., spatial and temporal variability, including seasonality, interannual variability, and trends), and different vegetation indices may not be equally good at predicting them. Their accuracy in monitoring productivity has been mostly tested in single-ecosystem studies, but their performance in different ecosystems distributed over large areas still needs to be fully explored. To fill this gap, we identified the facets of terrestrial gross primary production (GPP) that could be monitored using RSVIs. We compared the temporal and …

Relationships Between Landscape Constraints And A Crayfish Assemblage With Consideration Of Competitor Presence, Joshua B. Mouser, Robert Mollenhauer, Shannon K. Brewer

United States Geological Survey: Staff Publications

Aim: Crayfish are globally diverse and one of the most important taxa in North American streams. Despite their importance, many species are of conservation concern and efforts to improve conditions are limited. Here, we address two major impediments to improving conditions: (a) our lack of knowledge of the interplay among natural landscape and human-induced changes; and (b) a very limited understanding of how species interactions affect overall crayfish distributions.

Location: Ozark Highlands ecoregion, USA.

Methods: We used both existing data and field-collected data to examine the relationships between 12 Faxonius species and physicochemical variables at multiple spatial scales. Data were …

Nebraska Wetland Condition Assessment: Intensification Of The National Wetland Condition Assessment Throughout Nebraska, Cody Dreier

School of Natural Resources: Dissertations, Theses, and Student Research

Even though wetlands provide a habitat for many plants and animals and numerous services for humans, they were not always treated as areas of value. Less than half of the United States’ pre-colonial wetlands have survived to the present day. Seeing a need to understand the remaining wetlands more fully, the Environmental Protection Agency developed the National Wetland Condition Assessment to monitor target wetlands throughout the country every five years.

This study is an intensification of the National Wetland Condition Assessment for Nebraska wetlands that allowed us to sample more areas of the state and gather additional information. During the …

The Flathead Catfish Invasion Of The Great Lakes, Pam L. Fuller, Gary E. Whelan

United States Geological Survey: Staff Publications

A detailed review of historical literature andmuseumdata revealed that flathead catfish were not historically native in the Great Lakes Basin, with the possible exception of a relict population in Lake Erie. The species has invaded Lake Erie, Lake St. Clair, Lake Huron, nearly all drainages in Michigan, and the Fox/Wolf and Milwaukee drainages in Wisconsin. They have not been collected from Lake Superior yet, and the temperature suitability of that lake is questionable. Flathead catfish have been stocked sparingly in the Great Lakes and is not the mechanism responsible for their spread. A stocking in 1968 in Ohio may be …

Recent Ecological Change In Ancient Lakes, Stephanie E. Hampton, Suzanne Mcgowan, Ted Ozersky, Salvatore G. P. Virdis, Tuong Thuy Vu, Trisha L. Spanbauer, Benjamin M. Kraemer, George Swann, Anson W. Mackay, Stephen M. Powers, Michael F. Meyer, Stephanie G. Labou, Catherine M. O'Reilly, Morgan Dicarlo, Aaron W. E. Galloway, Sherilyn C. Fritz

Department of Earth and Atmospheric Sciences: Faculty Publications

Ancient lakes are among the best archivists of past environmental change, having experienced more than one full glacial cycle, a wide range of climatic conditions, tectonic events, and long association with human settlements. These lakes not only record long histories of environmental variation and human activity in their sediments, but also harbor very high levels of biodiversity and endemism. Yet, ancient lakes are faced with a familiar suite of anthropogenic threats, which may degrade the unusual properties that make them especially valuable to science and society. In all ancient lakes for which data exist, significant warming of surface waters has …

Greater Sage-Grouse Population Trends Across Wyoming, David R. Edmunds, Cameron L. Aldridge, Michael S. O'Donnell, Adrian P. Monroe

United States Geological Survey: Staff Publications

The scale at which analyses are performed can have an effect on model results and often one scale does not accurately describe the ecological phenomena of interest (e.g., population trends) for wide-ranging species: yet, most ecological studies are performed at a single, arbitrary scale. To best determine local and regional trends for greater sage-grouse (Centrocercus urophasianus) in Wyoming, USA, we modeled density-independent and -dependent population growth across multiple spatial scales relevant to management and conservation (Core Areas [habitat encompassing approximately 83% of the sage-grouse population on ~24% of surface area in Wyoming], local Working Groups [7 regional areas for …

Semi-Arid Grassland Bird Responses To Patch-Burn Grazing And Drought, Susan K. Skagen, David J. Augustine, Justin D. Derner

United States Geological Survey: Staff Publications

As grassland birds of central North America experience steep population declines with changes in land use, management of remaining tracts becomes increasingly important for population viability. The integrated use of fire and grazing may enhance vegetation heterogeneity and diversity in breeding birds, but the subsequent effects on reproduction are unknown. We examined the influence of patch-burn grazing management in shortgrass steppe in eastern Colorado on habitat use and reproductive success of 3 grassland bird species, horned lark (Eremophila alpestris), lark bunting (Calamospiza melanocorys), and McCown’s longspur (Rhynchophanes mccownii), at several spatial scales during 2011 …

Balancing Stability And Flexibility In Adaptive Governance: An Analysis Of Tools Available In U.S. Environmental Law, Robin Kundis Craig, Ahjond S. Garmestani, Craig R. Allen, Craig Anthony (Tony) Arnold, Hannah E. Birge, Hannah Birge, Daniel A. Decaro, Alexander K. Fremier, Alexander K. Fremier, Hannah Gosnell, Edella C. Schlager

United States Geological Survey: Staff Publications

Adaptive governance must work “on the ground,” that is, it must operate through structures and procedures that the people it governs perceive to be legitimate and fair, as well as incorporating processes and substantive goals that are effective in allowing social-ecological systems (SESs) to adapt to climate change and other impacts. To address the continuing and accelerating alterations that climate change is bringing to SESs, adaptive governance generally will require more flexibility than prior governance institutions have often allowed. However, to function as good governance, adaptive governance must pay real attention to the problem of how to balance this increased …

Key Differences Between Lakes And Reservoirs Modify Climate Signals: A Case For A New Conceptual Model, Nicole M. Hayes, Bridget R. Deemer, Jessica R. Corman, N. Roxanna Razavi, Kristin E. Strock

United States Geological Survey: Staff Publications

Lakes and reservoirs are recognized as important sentinels of climate change, integrating catchment and atmospheric climate change drivers. Climate change conceptual models generally consider lakes and reservoirs together despite the possibility that these systems respond differently to climate-related drivers. Here, we synthesize differences between lake and reservoir characteristics that are likely important for predicting waterbody response to climate change. To better articulate these differences, we revised the energy mass flux framework, a conceptual model for the effects of climate change on lentic ecosystems, to explicitly consider the differential responses of lake versus reservoir ecosystems. The model predicts that catchment and …

Using Ecological Production Functions To Link Ecological Processes To Ecosystem Services, Randall Jf Bruins, Timothy J. Canfield, Clifford Duke, Larry Kapustka, Amanda M. Nahlik, Ralf B. Schäfer

United States Environmental Protection Agency: Staff Publications

Ecological production functions (EPFs) link ecosystems, stressors, and management actions to ecosystem services (ES) production. Although EPFs are acknowledged as being essential to improve environmental management, their use in ecological risk assessment has received relatively little attention. Ecological production functions may be defined as usable expressions (i.e., models) of the processes by which ecosystems produce ES, often including external influences on those processes. We identify key attributes of EPFs and discuss both actual and idealized examples of their use to inform decision making. Whenever possible, EPFs should estimate final, rather than intermediate, ES. Although various types of EPFs have been …

Hydrothermal Monitoring In Yellowstone National Park Using Airborne Thermal Infrared Remote Sensing, C. M. U. Neale, C. Jaworowski, H. Heasler, S. Sivarajan, A. Masih

Daugherty Water for Food Global Institute: Faculty Publications

This paper describes the image acquisition and processing methodology, including surface emissivity and atmospheric corrections, for generating surface temperatures of two active hydrothermal systems in Yellowstone National Park. Airborne thermal infrared (8–12 μm) images were obtained annually from 2007 to 2012 using a FLIR SC640 thermal infrared camera system. Thermal infrared image acquisitions occurred under clear-sky conditions after sunset to meet the objective of providing high-spatial resolution, georectified imagery for hydrothermal monitoring. Comparisons of corrected radiative temperature maps with measured ground and water kinetic temperatures at flight times provided an assessment of temperature accuracy. A repeatable, time-sequence of images for …

Endangered Species Research In Hawaii: The Early Years (1965–87), Michael J. Scott, Cameron B. Kepler

United States Geological Survey: Staff Publications

Hawaii is an ecologically isolated archipelago 2,500 miles from the nearest continent. Its isolation resulted in a taxonomically unbalanced flora and fauna with remarkable examples of adaptive radiation among those groups of organisms that won the dispersal sweepstakes. It was one of the last oceanic island groups to be populated by humans, about 900 A.D. by Polynesian travelers and in 1778 by Europeans. Relatively recent colonization by humans did not save it, however, from the biodiversity losses suffered by other isolated archipelagos—it only delayed them (Scott and others, 1988; Pratt and others, 2009a).

Patuxent’S Long-Term Research On Wolves, David L. Mech

United States Geological Survey: Staff Publications

The gray wolf (Canis lupus) was one of the first species placed on the Endangered Species List in 1967. The Endangered Species Act of 1973 legally protected the wolf along with other listed species. Patuxent Wildlife Research Center (Patuxent) in Laurel, MD, began its Endangered Wildlife Program in 1966, and U.S. Fish and Wildlife Service (USFWS) biologist Ray Erickson was assigned to lead it. In 1973, I was transferred to the program from Region 3 of the USFWS, having been employed there since 1969 to study wolves in Minnesota. Endangered Species Act protection of the wolf fostered its …

Hydrologic Mediation Of The Spatial And Temporal Variability Of The Soil Carbon Dioxide Stable Isotopic Composition Of A Subalpine Watershed, Theresa Marie Lorenzo

School of Natural Resources: Dissertations, Theses, and Student Research

The stable carbon isotopic composition of CO₂ (δ¹³C-CO₂) has been studied as an indicator of changes in ecosystem CO₂ exchange. Soil moisture is an important factor in ecosystem CO₂ exchange through its influence on physiological and soil physical processes. However, the majority of previous research analyzing the influence of soil moisture on soil and soil-respired δ¹³C-CO₂ has been conducted with limited consideration of topographical variation, which controls the distribution of soil moisture across a landscape. This study characterized the stable isotopic composition (δ¹³C) and concentrations of soil CO …

Sea Level And Turbidity Controls On Mangrove Soil Surface Elevation Change, Catherine E. Lovelock, Maria Fernanda Adame, Vicki Bennion, Matthew Hayes, Ruth Reef, Nadia Santini, Donald R. Cahoon

United States Geological Survey: Staff Publications

Increases in sea level are a threat to seaward fringing mangrove forests if levels of inundation exceed the physiological tolerance of the trees; however, tidal wetlands can keep pace with sea level rise if soil surface elevations can increase at the same pace as sea level rise. Sediment accretion on the soil surface and belowground production of roots are proposed to increase with increasing sea level, enabling intertidal habitats to maintain their position relative to mean sea level, but there are few tests of these predictions in mangrove forests. Here we used variation in sea level and the availability of …

Estimating Relative Sea-Level Rise And Submergence Potential At A Coastal Wetland, Donald R. Cahoon

United States Geological Survey: Staff Publications

A tide gauge records a combined signal of the vertical change (positive or negative) in the level of both the sea and the land to which the gauge is affixed; or relative sealevel change, which is typically referred to as relative sea-level rise (RSLR). Complicating this situation, coastal wetlands exhibit dynamic surface elevation change (both positive and negative), as revealed by surface elevation table (SET) measurements, that is not recorded at tide gauges. Because the usefulness of RSLR is in the ability to tie the change in sea level to the local topography, it is important that RSLR be calculated …

Diagenetic Incorporation Of Sr Into Aragonitic Bivalve Shells: Implications For Chronostratigraphic And Palaeoenvironmental Interpretations, Maria C. Marcano, Tracy D. Frank, Samuel B. Mukasa, Kyger C. Lohmann, Marco Taviani

Department of Earth and Atmospheric Sciences: Faculty Publications

Aragonite is easily altered during diagenesis, therefore presumed pristine when present. In effect, beyond polymorphic transformation to calcite, alteration paths of aragonite remain poorly understood despite heavy reliance on such material to produce palaeoenvironmental and chronostratigraphic interpretations. Previous work on core material from Southern McMurdo Sound, Antarctica, showed that unlike their calcitic counterparts, seemingly unaltered aragonite shell fragments invariably produced older than expected ⁸⁷Sr/⁸⁶Sr ages. In this study, we pursued additional analyses of these aragonite shells and of the porewater of the core to understand this discrepancy. Aragonite mineralogy was reconfirmed and elemental mapping of shell fragments …

Pore Water Extraction For Unsaturated Zone Isotope Research: An Investigation Using An Immiscible Displacement Fluid And A Centrifuge, Caitlin Burnett Weaver

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Accurate and reliable pore water extraction techniques are important to an array of scientific fields including, but not limited to, hydrogeology, soil science, and paleoenvironmental research. The aim of the current project is to test the applicability of an immiscible displacement extraction technique for stable isotopes of water under a range of textural, hydrologic, and chemical conditions. In this study, laboratory experiments were conducted to establish the extent to which the proposed method 1) achieves sufficient yield for laboratory isotopic analyses, 2) results in isotopic exchange between water and the displacement fluid, 3) conserves initial isotopic compositions of spike test …

A Global Standard For Monitoring Coastal Wetland Vulnerability To Accelerated Sea-Level Rise, Edward L. Webb, Daniel A. Friess, Ken W. Krauss, Donald R. Cahoon, Glenn R. Guntenspergen, Jacob Phelps

United States Geological Survey: Staff Publications

Sea-level rise threatens coastal salt-marshes and mangrove forests around the world, and a key determinant of coastal wetland vulnerability is whether its surface elevation can keep pace with rising sea level. Globally, a large data gap exists because wetland surface and shallow subsurface processes remain unaccounted for by traditional vulnerability assessments using tide gauges. Moreover, those processes vary substantially across wetlands, so modelling platforms require relevant local data. The low-cost, simple, high-precision rod surface-elevation table–marker horizon (RSET-MH) method fills this critical data gap, can be paired with spatial data sets and modelling and is financially and technically accessible to every …

Heterogeneous Detection Probabilities For Imperiled Missouri River Fishes: Implications For Large-River Monitoring Programs, Joshua T. Schloesser, Craig P. Paukert, Wyatt J. Doyle, Tracy D. Hill, Kirk D. Steffensen, Vince H. Travnichek

United States Geological Survey: Staff Publications

Occupancy modeling was used to determine (1) if detection probabilities (p) for 7 regionally imperiled Missouri River fishes (Scaphirhynchus albus, Scaphirhynchus platorynchus, Cycleptus elongatus, Sander canadensis, Macrhybopsis aestivalis, Macrhybopsis gelida, and Macrhybopsis meeki) differed among gear types (i.e. stationary gill nets, drifted trammel nets, and otter trawls), and (2) how detection probabilities were affected by habitat (i.e. pool, bar, and open water), longitudinal position (five 189 to 367 rkm long segments), sampling year (2003 to 2006), and season (July 1 to October 30 and October 31 to June 30). Adult, large-bodied fishes were …

Sorta Situ: The New Reality Of Management Conditions For Wildlife Populations In The Absence Of "Wild" Spaces, Barbara A. Wolfe, Roberto F. Aguilar, A. Alonso Aguirre, Glenn H. Olsen, Evan S. Blumer

United States Geological Survey: Staff Publications

The rate of species loss today is approaching catastrophic levels. Scientists project that over the next two decades, more than 1 million species of plants and animals will become extinct. E.O. Wilson has estimated that "the rate ofloss may exceed 50,000 a year, 137 a day ... this rate, while horrendous, is actually the minimal estimate, based on the species/area relationship alone" (Kellert and Wilson 1993, p. 16; Aguirre 2009). Ever-expanding communities, strained natural resources, changes in land use, and other anthropogenic drivers are compromising ecosystems and rapidly changing the landscape and the availability of "wild" spaces.

Gene Transcription In Sea Otters (Enhydra Lutris); Development Of A Diagnostic Tool For Sea Otter And Ecosystem Health, Lizabeth Bowen, A. Keith Miles, Michael Murray, Martin Haulena, Judy Tuttle, William Van Bonn, Lance Adams, James L. Bodkin, Brenda Ballachey, James A. Estes, M. Tim Tinker, Robin Keister, Jeffrey L. Stott

United States Geological Survey: Staff Publications

Gene transcription analysis for diagnosing or monitoring wildlife health requires the ability to distinguish pathophysiological change from natural variation. Herein, we describe methodology for the development of quantitative real-time polymerase chain reaction (qPCR) assays to measure differential transcript levels of multiple immune function genes in the sea otter (Enhydra lutris); sea otter-specific qPCR primer sequences for the genes of interest are defined. We establish a ‘reference’ range of transcripts for each gene in a group of clinically healthy captive and free-ranging sea otters. The 10 genes of interest represent multiple physiological systems that play a role in immuno-modulation, …

Introduction To “Environmental Contaminants In Biota, 2nd Edition”, W. Nelson Beyer, James P. Meador

United States Geological Survey: Staff Publications

Ecotoxicology is the study of the movement of environmental contaminants through ecosystems and their effects on plants and animals. Examining tissue residues of these contaminants in biota is basic to ecotoxicology, both for understanding the movement of contaminants within organisms and through food chains, and for understanding and quantifying injuries to organisms and their communities. This book provides guidance on interpreting tissue concentrations of environmental contaminants.

Tissue concentrations have long been used both to identify the cause of toxicity in animals and as a measure of the severity of toxicity. More recently, they have been incorporated into environmental models, tying …

Mississippi Canyon 252 Incident Nrda Tier 1 For Deepwater Communities, Gregory Boland, Gary Brewer, Erik Cordes, Amanda Demopoulos, Chuek Fisher, Chris German, Ken Sulak

United States Geological Survey: Staff Publications

The northern Gulf of Mexico (GOM) is geologically diverse basin, described as the most complex continental slope region in the world. Regional topography of the slope consists of basins, knolls, ridges, and mounds derived from the dynamic adjustments of salt and the introduction of large volumes of sediment over long time scales. More than 99% of the sea floor in the GOM consists of soft sediment made up of various mixtures of primarily silt and clay. These wide-spread soft bottom communities are described in reports from major MMS studies by Gallaway et al. (1998) and Rowe and Kennicutt (2009). Relative …