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Aquatic Pollution Increases Use Of Terrestrial Prey Subsidies By Stream Fish, Johanna M. Kraus, Justin F. Pomeranz, Andrew S. Todd, David M. Walters, Travis S. Schmidt, Richard B. Wanty Jan 2015

Aquatic Pollution Increases Use Of Terrestrial Prey Subsidies By Stream Fish, Johanna M. Kraus, Justin F. Pomeranz, Andrew S. Todd, David M. Walters, Travis S. Schmidt, Richard B. Wanty

United States Geological Survey: Staff Publications

1. Stream food webs are connected with their riparian zones through cross-ecosystem movements of energy and nutrients. The use and impact of terrestrial subsidies on aquatic consumers is often determined by in situ biomass of aquatic prey. Thus, stressors such as aquatic pollutants that greatly reduce aquatic secondary production could increase the need for and reliance of stream consumers on terrestrial resource subsidies.

2. To test this hypothesis, we surveyed stream fish, their diets, and resource availability in 16 subalpine streams over a regional gradient of trace metals known to strongly impact aquatic insect communities (i.e. fish prey) in …


Investigating Endocrine And Physiological Parameters Of Captive American Kestrels Exposed By Diet To Selected Organophosphate Flame Retardants, Kimberly J. Fernie, Vince Palace, Lisa E. Peters, Nil Basu, Robert J. Letcher, Natalie K. Karouna-Renier, Sandra L. Schultz, Rebecca S. Lazarus, Barnett A. Rattner Jan 2015

Investigating Endocrine And Physiological Parameters Of Captive American Kestrels Exposed By Diet To Selected Organophosphate Flame Retardants, Kimberly J. Fernie, Vince Palace, Lisa E. Peters, Nil Basu, Robert J. Letcher, Natalie K. Karouna-Renier, Sandra L. Schultz, Rebecca S. Lazarus, Barnett A. Rattner

United States Geological Survey: Staff Publications

Organophosphate triesters are high production volume

additive flame retardants (OPFRs) and plasticizers. Shown to accumulate

in abiotic and biotic environmental compartments, little is known about the

risks they pose. Captive adult male American kestrels (Falco sparverius) were

fed the same dose (22 ng OPFR/g kestrel/d) daily (21 d) of tris(2-

butoxyethyl) phosphate (TBOEP), tris(2-chloroethyl) phosphate (TCEP),

tris(2-chloroisopropyl) phosphate (TCIPP), or tris(1,2-dichloro-2-propyl)

phosphate (TDCIPP). Concentrations were undetected in tissues (renal,

hepatic), suggesting rapid metabolism. There were no changes in glutathione

status, indicators of hepatic oxidative status, or the cholinergic system (i.e.,

cerebrum, plasma cholinesterases; cerebrum muscarinic, nicotinic receptors).

Modest …


Use Of Terrestrial Field Studies In The Derivation Of Bioaccumulation Potential Of Chemicals, Nico W. Van Den Brink, Jennifer A. Arblaster, Sarah R. Bowman, Jason M. Conder, John E. Elliott, Mark S. Johnson, Derek C.G. Muir, Tiago Natal-Da-Luz, Barnett A. Rattner, Bradley E. Sample, Richard F. Shore Jan 2015

Use Of Terrestrial Field Studies In The Derivation Of Bioaccumulation Potential Of Chemicals, Nico W. Van Den Brink, Jennifer A. Arblaster, Sarah R. Bowman, Jason M. Conder, John E. Elliott, Mark S. Johnson, Derek C.G. Muir, Tiago Natal-Da-Luz, Barnett A. Rattner, Bradley E. Sample, Richard F. Shore

United States Geological Survey: Staff Publications

Field-based studies are an essential component of research addressing the behavior of organic chemicals, and a unique line of evidence that can be used to assess bioaccumulation potential in chemical registration programs and aid in development of associated laboratory and modeling efforts. To aid scientific and regulatory discourse on the application of terrestrial field data in this manner, this article provides practical recommendations regarding the generation and interpretation of terrestrial field data. Currently, biota-to-soil-accumulation factors (BSAFs), biomagnification factors (BMFs), and bioaccumulation factors (BAFs) are the most suitable bioaccumulation metrics that are applicable to bioaccumulation assessment evaluations and able to be …


Estimating Relative Sea-Level Rise And Submergence Potential At A Coastal Wetland, Donald R. Cahoon Jan 2015

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 …


Traditional Medicine Usage And The Transmission Of Traditional Ecological Knowledge In Three Villages Near Phnom Kulen National Park, Kayla N. Deur Jan 2015

Traditional Medicine Usage And The Transmission Of Traditional Ecological Knowledge In Three Villages Near Phnom Kulen National Park, Kayla N. Deur

Environmental Studies / Environmental Science Student Scholarship

Traditional ecological knowledge refers to knowledge regarding the relationships between humans and the natural environment. This knowledge and skill set is acquired by local and indigenous peoples through generations of direct contact with the environment, and is often shared in an intergenerational pattern of verbal retelling and instruction. Traditional medicine is one component of traditional ecological knowledge, and this paper outlines the investigation of traditional medicine usage and the transmission of such knowledge in three villages near Phnom Kulen National Park in Siem Reap, Cambodia. The study was conducted through semi-structured interviews at homes that were both randomly and purposively …


Morphology And Niche Partitioning Of Fish Assemblage In The Tonle Sap Biosphere Reserve - A Case Study Of The Prek Toal Core Area, Lan Thi Ngoc Nguyen Jan 2015

Morphology And Niche Partitioning Of Fish Assemblage In The Tonle Sap Biosphere Reserve - A Case Study Of The Prek Toal Core Area, Lan Thi Ngoc Nguyen

Environmental Studies / Environmental Science Student Scholarship

A morphological approach provides vital information on community structure and ecological adjustments among different species that occupy in the same habitat. The coexistence of competing species in a diverse community results in niche partitioning in order to increase stabilization. Tonle Sap Biosphere Reserve, one of the world’s most productive inland wetlands is a tropical river ecosystem so dynamic that supports high biodiversity, especially fish population. This study tests the relationship between morphology and niche partitioning to understand the coexistence of diverse fish assemblages in the Tonle Sap Biosphere Reserve. By measuring 31 morphological variables and gathering ecological data of the …


A Mixed-Methods Approach To Assessing Success In Transitioning Water Management Institutions: A Case Study Of The Platte River Basin, Nebraska, Christina Hoffman Babbitt, Mark E. Burbach, Lisa Pennisi Jan 2015

A Mixed-Methods Approach To Assessing Success In Transitioning Water Management Institutions: A Case Study Of The Platte River Basin, Nebraska, Christina Hoffman Babbitt, Mark E. Burbach, Lisa Pennisi

School of Natural Resources: Faculty Publications

To address increasing conflicts between surface water and groundwater users, the state of Nebraska has adopted a more localized and integrated approach in managing water resources. Integrated approaches offer promise in better managing connected water resources within the state; however, little review of the potential benefits and/or challenges of these actions has been conducted. This case study uses both qualitative and quantitative data collection efforts to take an in-depth look at how this new and innovative management system is working through the eyes of stakeholders living and working in the basin. Data collection reveals that overall the current water management …


Predictions Of Future Ephemeral Springtime Waterbird Stopover Habitat Availability Under Global Change, Daniel R. Uden, Craig R. Allen, Andrew A. Bishop, Roger Grosse, Christopher F. Jorgensen, Theodore G. Lagrange, Randy G. Stutheit, Mark P. Vrtiska Jan 2015

Predictions Of Future Ephemeral Springtime Waterbird Stopover Habitat Availability Under Global Change, Daniel R. Uden, Craig R. Allen, Andrew A. Bishop, Roger Grosse, Christopher F. Jorgensen, Theodore G. Lagrange, Randy G. Stutheit, Mark P. Vrtiska

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

In the present period of rapid, worldwide change in climate and landuse (i.e., global change), successful biodiversity conservation warrants proactive management responses, especially for long-distance migratory species. However, the development and implementation of management strategies can be impeded by high levels of uncertainty and low levels of control over potentially impactful future events and their effects. Scenario planning and modeling are useful tools for expanding perspectives and informing decisions under these conditions. We coupled scenario planning and statistical modeling to explain and predict playa wetland inundation (i.e., presence/absence of water) and ponded area (i.e., extent of water) in the Rainwater …


The Importance Of Scaling For Detecting Community Patterns: Success And Failure In Assemblages Of Introduced Species, Craig R. Allen, David G. Angeler, Michael P. Moulton, Crawford S. Holling Jan 2015

The Importance Of Scaling For Detecting Community Patterns: Success And Failure In Assemblages Of Introduced Species, Craig R. Allen, David G. Angeler, Michael P. Moulton, Crawford S. Holling

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Community saturation can help to explain why biological invasions fail. However, previous research has documented inconsistent relationships between failed invasions (i.e., an invasive species colonizes but goes extinct) and the number of species present in the invaded community. We use data from bird communities of the Hawaiian island of Oahu, which supports a community of 38 successfully established introduced birds and where 37 species were introduced but went extinct (failed invasions). We develop a modified approach to evaluate the effects of community saturation on invasion failure. Our method accounts (1) for the number of species present (NSP) when the species …


Sustainability And Economic Analysis Of Propylene Carbonate And Polypropylene Carbonate Production Processes Using Co2 And Propylene Oxide, Yaşar Demirel Jan 2015

Sustainability And Economic Analysis Of Propylene Carbonate And Polypropylene Carbonate Production Processes Using Co2 And Propylene Oxide, Yaşar Demirel

Yaşar Demirel Publications

Currently, the industrially important polycarbonates are synthesized from bisphenol A and diphenyl carbonate, which are highly toxic and hence other feasible alternatives are preferable. Following the considerable advances on the catalyst for the synthesis of carbonates from CO2 and propylene oxide (PO), industrial scale processes for the productions of propylene carbonate (PC) and polypropylene carbonate (PPC) have been designed and simulated with sustainability and economic analyses. The CO2 is supplied by a nearby bioethanol plant, while the PO from a petrochemical process. The first part of the study is for the production of 200 million lb/year cyclic PC …


Five-Year Growth Report: From Inception To Global Influence 2010 - 2015, Robert B. Daugherty Water For Food Institute Jan 2015

Five-Year Growth Report: From Inception To Global Influence 2010 - 2015, Robert B. Daugherty Water For Food Institute

Daugherty Water for Food Global Institute: Administrative Materials

While we are proud of our accomplishments in building an institutional framework, we are even more proud of our institute’s initial work to build an impact-driven program. This work is indeed the central focus of this report. Through the leadership of our new directors for research and policy, we have begun to build a vigorous research and policy development program that includes engagement with both local and global stakeholders. We have also developed a strong set of collaborations with national and international partners, striving to achieve a balance between work in Nebraska and globally, including in India, Brazil, China and …


Nebraska Water Center Annual Report 2015, Nebraska Water Center Jan 2015

Nebraska Water Center Annual Report 2015, Nebraska Water Center

Nebraska Water Center: Administrative Materials

Contents

Foreword 4

The Nebraska Water Center: Leadership in Research, Education and Communication 6

Director’s Letter 8

For More Than 50 years: The Nebraska Water Center 10

Helping Build the Future 11

Nebraska Water Center Advisory Board 14

Water Resources Advisory Panel: A key to success 15

Information for Our Clients and the Public 16

Primary Goals 18

USGS 104b Projects 20

Dvorak, Ray Aim at Improving Water Quality for Small Communities 20

October Retreat at UNK 24

Public Water Lectures 25

2015 Special Seminars 26

2015 Water Symposium and Water Law Conference 28

Water Tour Visits Republican River Basin …


The Effects Of Harvest Regulations On Behaviors Of Duck Hunters, Matthew T. Haugen, Larkin A. Powell, Mark P. Vrtiska, Kevin L. Pope Jan 2015

The Effects Of Harvest Regulations On Behaviors Of Duck Hunters, Matthew T. Haugen, Larkin A. Powell, Mark P. Vrtiska, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Uncertainty exists as to how duck harvest regulations influence waterfowl hunter behavior. We used the U.S. Fish and Wildlife Service’s Parts Collection Survey to examine how harvest regulations affected behaviors of Central Flyway duck hunters. We stratified hunters into ranked groups based on seasonal harvest and identified three periods (1975–1984, 1988–1993, 2002–2011) that represented different harvest regulations (moderate, restrictive, and liberal, respectively; season length and daily bag limits smallest in restrictive seasons and largest in liberal seasons). We examined variability of seven measures of duck hunter behaviors across the periods: days harvesting ducks, daily harvest, hunter mobility, mallard (Anas platyrhynchos …


Masked Expression Of Life- History Traits In A Highly Variable Environment, Jason A. Deboer, Joseph J. Fontaine, Christopher J. Chizinski, Kevin L. Pope Jan 2015

Masked Expression Of Life- History Traits In A Highly Variable Environment, Jason A. Deboer, Joseph J. Fontaine, Christopher J. Chizinski, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Differing life-history strategies may act as a constraint on reproductive expression that ultimately limits the ability of individual species to respond to changes in the magnitude or frequency of environmental variation, and potentially underlies the variation oft en inherent in phenotypic and evolved responses to anthropogenic change. Alternatively, if there are environmental cues that predict reproductive potential, differential expression of life-history strategies may represent differences in the adaptive capacity to optimize current reproductive value given variation in environmental conditions. We compared several aspects of walleye Sander vitreus spawning ecology at two reservoirs that diff er in environmental variability (i.e., annual …


Global Change And Conservation Triage On National Wildlife Refuges, Fred Johnson, Mitchell J. Eaton, Gerard Mcmahon, Raye Nilius, Michael R. Bryant, Dave Case, Julien Martin, Nathan J. Wood, Laura Taylor Jan 2015

Global Change And Conservation Triage On National Wildlife Refuges, Fred Johnson, Mitchell J. Eaton, Gerard Mcmahon, Raye Nilius, Michael R. Bryant, Dave Case, Julien Martin, Nathan J. Wood, Laura Taylor

United States Geological Survey: Staff Publications

National Wildlife Refuges (NWRs) in the United States play an important role in the adaptation of social-ecological systems to climate change, land-use change, and other global-change processes. Coastal refuges are already experiencing threats from sea-level rise and other change processes that are largely beyond their ability to influence, while at the same time facing tighter budgets and reduced staff. We engaged in workshops with NWR managers along the U.S. Atlantic coast to understand the problems they face from global-change processes and began a multidisciplinary collaboration to use decision science to help address them. We are applying a values-focused approach to …


Uncertainty Analysis Of An Irrigation Scheduling Model For Water Management In Crop Production, S. Mun, G. F. Sassenrath, Amy M. Schmidt, N. Lee, M. C. Wadsworth, B. Rice, Jason Q, Corbitt, J. M. Schneider, M. L. Tagert, J. Pote, R. Prabhu Jan 2015

Uncertainty Analysis Of An Irrigation Scheduling Model For Water Management In Crop Production, S. Mun, G. F. Sassenrath, Amy M. Schmidt, N. Lee, M. C. Wadsworth, B. Rice, Jason Q, Corbitt, J. M. Schneider, M. L. Tagert, J. Pote, R. Prabhu

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Irrigation scheduling tools are critical to allow producers to effectively manage water resources for crop production. To be useful, these tools need to be accurate, complete, and relatively reliable. The current work presents an uncertainty analysis and its results for the Mississippi Irrigation Scheduling Tool (MIST) model, showing the margin of error (uncertainty) of the resulting irrigation advice arising solely from the propagation of measurement uncertainty through the MIST calculations. The final relative uncertainty in the water balance value from MIST was shown to be around 9% of that value, which is in the normal range of the margin of …


Magnetic Mineral Diagenesis In The River‐Dominated Inner Shelf Of The East China Sea, China, Can Ge, Weiguo Zhang, Chenyin Dong, Yan Dong, Jinyan Liu, Nguyen Thi Thu Hien, Huan Feng, Lizhong Yu Jan 2015

Magnetic Mineral Diagenesis In The River‐Dominated Inner Shelf Of The East China Sea, China, Can Ge, Weiguo Zhang, Chenyin Dong, Yan Dong, Jinyan Liu, Nguyen Thi Thu Hien, Huan Feng, Lizhong Yu

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The inner shelf of the East China Sea is a river-dominated margin characterized by fine-grained mud deposits and a rapid sedimentation rate. Three short sediment cores (similar to 2.7m in length) were examined to characterize spatial variations in magnetic mineral diagenesis. The sediment cores were analyzed for sedimentation rates, magnetic properties, particle size distribution, organic carbon, and total sulfur content. The two more proximal cores with higher sedimentation rates (similar to 2.2cm/yr and similar to 0.96cm/yr) do not exhibit obvious effects of reductive dissolution of magnetite with increasing depth, which is consistent with their lower total sulfur content. The offshore …


Determining Soil Texture By Feel, Edwin L. Ritchey, Joshua M. Mcgrath, David Gehring Jan 2015

Determining Soil Texture By Feel, Edwin L. Ritchey, Joshua M. Mcgrath, David Gehring

Agriculture and Natural Resources Publications

Soil texture refers to the proportion of sand, silt, and clay in a soil. Texture influences almost every aspect of soil use, both in agricultural and engineering applications, and even how natural ecosystems function. Many scientists consider soil texture the most important soil property as it can influence soil/water relationships, gas exchange, and plant nutrition. Accurately determining soil texture in a lab requires time and money; therefore, it is often necessary to estimate soil texture in the field by feel, which can be very accurate if done correctly.


Zebra Mussel (Dreissena Polymorpha) Habitat Associations In Four West-Central Minnesota Lakes, April Rose Londo Jan 2015

Zebra Mussel (Dreissena Polymorpha) Habitat Associations In Four West-Central Minnesota Lakes, April Rose Londo

All Graduate Theses, Dissertations, and Other Capstone Projects

In 1989, zebra mussels (Dreissena polymorpha) were first documented in the land of ten thousand lakes in the Lake Superior Basin at Duluth. Zebra mussels are successful invaders because the species attaches to substrates with byssal threads, can adapt to a wide range of environmental conditions, and has a free-swimming veligers that are easily transported. Although invasive mollusks pose a range of economic and ecological threats to inland waters, our understanding of zebra mussels in Minnesota lakes remains limited. To gain additional information regarding zebra mussel ecology in lake systems, I conducted research in four west-central Minnesota lakes that were …


An Ipm Scouting Guide For Common Problems Of Legume Vegetables In Kentucky, Nicole Ward Gauthier, Ricardo Bessin, Shubin Saha, Shawn Wright, Cheryl A. Kaiser Jan 2015

An Ipm Scouting Guide For Common Problems Of Legume Vegetables In Kentucky, Nicole Ward Gauthier, Ricardo Bessin, Shubin Saha, Shawn Wright, Cheryl A. Kaiser

Agriculture and Natural Resources Publications

Long before the term “sustainable” became a household word, farmers were implementing sustainable practices in the form of Integrated Pest Management (IPM) strategies. IPM uses a combination of biological, cultural, physical, and chemical methods to reduce and/or manage pest populations. These strategies are used to minimize environmental risks, economic costs, and health hazards. Pests are “managed” (but rarely eliminated entirely) to reduce their negative impact on the crop.

Scouting and monitoring diseases, insects, weeds, and abiotic disorders in order to identify potential problems before they result in serious losses is essential to the IPM approach. Proper identification is essential to …


Organic Corn Production In Kentucky, Michael Bomford, Lee Meyer, Thomas Sikora, William Martin, Sam Mcneill, Michael D. Montross, Edwin L. Ritchey, Chad Lee Jan 2015

Organic Corn Production In Kentucky, Michael Bomford, Lee Meyer, Thomas Sikora, William Martin, Sam Mcneill, Michael D. Montross, Edwin L. Ritchey, Chad Lee

Agriculture and Natural Resources Publications

The number of organic dairy cows in Kentucky has been steadily increasing for years, yet there’s not enough organic corn produced in the state to feed the growing herds. In fact, most of the organic corn consumed in Kentucky is produced outside of the state. The growing organic livestock and poultry industries in Kentucky face the same feed constraints. In short, a new market has developed in the state, but few local farmers are taking advantage of it.


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 Jan 2015

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 …


Training Conservation Practitioners To Be Better Decision Makers, Fred Johnson, Mitchell J. Eaton, James H. Williams, Gitte H. Jensen, Jesper Madsen Jan 2015

Training Conservation Practitioners To Be Better Decision Makers, Fred Johnson, Mitchell J. Eaton, James H. Williams, Gitte H. Jensen, Jesper Madsen

United States Geological Survey: Staff Publications

Traditional conservation curricula and training typically emphasizes only one part of systematic decision making (i.e., the science), at the expense of preparing conservation practitioners with critical skills in values-setting, working with decision makers and stakeholders, and effective problem framing. In this article we describe how the application of decision science is relevant to conservation problems and suggest how current and future conservation practitioners can be trained to be better decision makers. Though decision-analytic approaches vary considerably, they all involve: (1) properly formulating the decision problem; (2) specifying feasible alternative actions; and (3) selecting criteria for evaluating potential outcomes. Two approaches …


The Impacts Of Water Availability On Macroinvertebrate, Ector Matias Martell Jan 2015

The Impacts Of Water Availability On Macroinvertebrate, Ector Matias Martell

Open Access Theses & Dissertations

In many regions around the world climate is changing and biotic communities are changing with it. In areas like the southwestern U.S., drought is one of the major sources of disturbance. Although droughts are an integral part of the natural hydrological cycles, they can have devastating effects on freshwater ecosystems when disrupted by extended periods of drought, resulting in changes to the structure and function of biotic communities. In this study, we surveyed four streams in the Sacramento Mountains of New Mexico from 2010 to 2014: Agua Chiquita, Rio Peñasco, Wills Creek, and the Sacramento River; These years encompassed an …


The Role Of Funding Programs In Promotion Of Best Management Practices For Effective Stream Restoration, Tracy R. Wendt Jan 2015

The Role Of Funding Programs In Promotion Of Best Management Practices For Effective Stream Restoration, Tracy R. Wendt

Graduate Student Theses, Dissertations, & Professional Papers

Large amounts of money are spent on stream restoration projects across the United States every year. Restoration researchers and professionals commonly recommend a suite of Best Management Practices (BMPs), including project goals, objectives, monitoring, consideration of future conditions, adaptive management, and public reporting of results, which are widely recognized as contributing to effective projects. Studies over the last two decades demonstrated that these BMPs were not consistently incorporated into restoration projects, which highlighted the need to improve practices and for funding programs to incorporate BMPs into funding requirements. I reviewed 28 programs that fund stream restoration in the Rocky Mountain …


Remaking Nature In Montana: Topophilic Considerations Of Wolves And Wolf Trapping, Andrew Myers Jan 2015

Remaking Nature In Montana: Topophilic Considerations Of Wolves And Wolf Trapping, Andrew Myers

Graduate Student Theses, Dissertations, & Professional Papers

In 2011, after nearly forty years of federal protection, the gray wolf was removed from the Endangered Species List in Montana and its management entrusted to the Montana Fish, Wildlife & Parks. The implementation of public trapping seasons in 2012 as a method to control wolf populations has further inflamed an already embroiled debate. The purpose of this research was to investigate how the presence of wolves and wolf trapping impacts human attachments to landscapes of “nature” in Montana by focusing on the following questions: What are the public’s social constructions of wolves? What are the public’s social constructions of …


Linking The Effects Of Risk Factors On Annual Calf Survival To Elk Population Dynamics In The Bitterroot Valley, Montana, Daniel R. Eacker Jan 2015

Linking The Effects Of Risk Factors On Annual Calf Survival To Elk Population Dynamics In The Bitterroot Valley, Montana, Daniel R. Eacker

Graduate Student Theses, Dissertations, & Professional Papers

The recolonization of gray wolves (Canis lupus) in multiple carnivore systems has been correlated with declining recruitment of juvenile ungulates, but the importance of wolves relative to other established carnivores is uncertain. The realized effect of carnivores may depend on compensation from forage and winter weather severity, which may mediate juvenile vulnerability to predation. Also, in high predation systems, the importance of juvenile recruitment may be reduced for ungulate population dynamics. We first tested for the effects of risk factors on annual elk (Cervus elaphus) calf survival and estimated cause-specific mortality rates. Secondly, we investigated the …


An Economic Analysis Of High-Intensity, Short-Duration Grazing Systems In South Dakota And Nebraska, Bronc Mcmurtry Jan 2015

An Economic Analysis Of High-Intensity, Short-Duration Grazing Systems In South Dakota And Nebraska, Bronc Mcmurtry

Electronic Theses and Dissertations

Four different grazing systems: two rotational, a continuous, and a high-intensity, short-duration (mob) system, replicated twice, were evaluated from an economic perspective. Mob grazing is defined as a system having very high stocking rates for a small amount of time. Livestock are forced to eat or trample the vegetation. Stocking rates and average daily gains (ADG) were collected from the UNL Barta Brothers ranch near Rose, Nebraska. The study started in 2011 and lasted until 2014. Using the performance data and other cost data relevant to South Dakota and Nebraska, budgets were set up for each system and extrapolated to …


Population Ecology Of Rocky Mountain Elk In The Black Hills, South Dakota And Wyoming, Benjamin D. Simpson Jan 2015

Population Ecology Of Rocky Mountain Elk In The Black Hills, South Dakota And Wyoming, Benjamin D. Simpson

Electronic Theses and Dissertations

We conducted a 2-year (2012–2013) study of survival and cause–specific mortality using individually marked adult cow and neonate elk (Cervus elaphus) occupying the southwestern region of the Black Hills. We used known-fate analysis in Program MARK for survival analysis of adult cows and calves. We estimated survival and cause-specific mortality of 49 adult female elk over the 2 years of the study. Annual adult cow survival was 0.85 (95% CI = 0.72–0.87). We documented 12 mortalities with harvest (58.3%) and predation (16.6%) accounting for the majority of known mortalities. We captured and fit 71 neonates < 10 days of age with expandable Very High Frequency (VHF) radiocollars during summer 2012 (n = 37) and 2013 (n = 34). Annual (12 month) survival of elk calves was 0.75 (95% CI = 0.61–0.84) while summer (20 weeks; 15 May–25 September) survival was 0.79 (95% CI = 0.68–0.88). Predation accounted for 87.5% of mortalities; remaining mortalities were from starvation (6.3%) and unknown (6. 3%) causes. We used Global Positioning System (GPS) collars to collect 167,707 locations to determine home range, movement ecology, and macroscale resource selection of 48 adult cow elk. We documented elk using a variety of migration strategies (obligate migrator, resident, conditional migrator, disperser); the majority of the population (58%) was migratory. Spring migration distance travelled ranged from 2.45 km – 74.44 km (n = 42); fall migration distances ranged from 6.41km – 153.95 km (n = 46). We used 99% Brownian Bridge Movement Models to create seasonal and overall home ranges of adult cow elk. Mean overall home range size for conditional migrators was 249.28 km2 (SE = 28.60, n = 7, range = 233.75), for obligate migrant elk it was 227.18 km2 (SE = 13.94, n = 29, range = 346.83), and for resident elk it was 175.65 km2 (SE = 22.75, n = 11, range = 216.04). We used discrete choice models to determine resource selection at the macro-habitat scale of collared adult elk using ArcMap 10.1 data. Adult cow elk selected for open grassland/herbaceous areas and early successional forest areas close to forested edges at higher elevations. Our study showed that elk populations have the ability to thrive within an ecosystem with healthy predator populations.


Natural Nutrient Sources In The Cache River Watershed, Arkansas, M. K. Kilmer, N. Poe, S. Chappell, J. L. Bouldin Jan 2015

Natural Nutrient Sources In The Cache River Watershed, Arkansas, M. K. Kilmer, N. Poe, S. Chappell, J. L. Bouldin

Journal of the Arkansas Academy of Science

The growth of the hypoxic ‘dead zone’ in the Gulf of Mexico in recent years has placed increased focus on potential sources of nutrient pollution, with most of the focus being placed on watersheds where practices, including fertilizer application and land alterations combine to increase non-point source runoff. In this study, nutrient concentrations in surface waters of altered and unaltered areas of the Cache River Watershed, Arkansas, were compared to determine if agricultural land usage was responsible for the majority of nutrient inputs. Results suggest that for dissolved nitrites and orthophosphates, agricultural (altered) sites contribute significantly more than relatively unaltered …