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2020

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Full-Text Articles in Physical Sciences and Mathematics

Core Commitments For Field Trials Of Gene Drive Organisms, Kanya C. Long, Luke Alphey, George J. Annas, Cinnamon S. Bloss, Karl J. Campbell, Jackson Champer, Chun-Hong Chen, Amit Choudhary, George M. Church, James P. Collins, Kimberly L. Cooper, Jason A. Delborne, Owain R. Edwards, Claudia I. Emerson, Kevin Esvelt, Sam Weiss Evans, Robert M. Friedman, Valentino M. Gantz, Fred Gould, Sarah Hartley, Elizabeth Heitman, Janet Hemingway, Hirotaka Kanuka, Jennifer Kuzma, James V. Lavery, Yoosook Lee, Marce Lorenzen, Jeantine E. Lunshof, John M. Marshall, Philipp W. Messer, Craig Montell, Kenneth A. Oye, Megan J. Palmer, Philippos Aris Papathanos, Prasad N. Paradkar, Antoinette J. Piaggio, Jason L. Rasgon, Gordana Rašić, Larisa Rudenko, J. Royden Saah, Maxwell J. Scott, Jolene T. Sutton, Adam E, Vorsino, Omar S. Akbari Dec 2020

Core Commitments For Field Trials Of Gene Drive Organisms, Kanya C. Long, Luke Alphey, George J. Annas, Cinnamon S. Bloss, Karl J. Campbell, Jackson Champer, Chun-Hong Chen, Amit Choudhary, George M. Church, James P. Collins, Kimberly L. Cooper, Jason A. Delborne, Owain R. Edwards, Claudia I. Emerson, Kevin Esvelt, Sam Weiss Evans, Robert M. Friedman, Valentino M. Gantz, Fred Gould, Sarah Hartley, Elizabeth Heitman, Janet Hemingway, Hirotaka Kanuka, Jennifer Kuzma, James V. Lavery, Yoosook Lee, Marce Lorenzen, Jeantine E. Lunshof, John M. Marshall, Philipp W. Messer, Craig Montell, Kenneth A. Oye, Megan J. Palmer, Philippos Aris Papathanos, Prasad N. Paradkar, Antoinette J. Piaggio, Jason L. Rasgon, Gordana Rašić, Larisa Rudenko, J. Royden Saah, Maxwell J. Scott, Jolene T. Sutton, Adam E, Vorsino, Omar S. Akbari

USDA Wildlife Services: Staff Publications

We must ensure that trials are scientifically, politically, and socially robust, publicly accountable, and widely transparent.

Gene drive organisms (GDOs), whose genomes have been genetically engineered to spread a desired allele through a population, have the potential to transform the way societies address a wide range of daunting public health and environmental challenges. The development, testing, and release of GDOs, however, are complex and often controversial. A key challenge is to clarify the appropriate roles of developers and others actively engaged in work with GDOs in decision-making processes, and, in particular, how to establish partnerships with relevant authorities and other …


Spectral Properties Of A Non-Compact Operator In Ecology, Matthew Reichenbach Dec 2020

Spectral Properties Of A Non-Compact Operator In Ecology, Matthew Reichenbach

Department of Mathematics: Dissertations, Theses, and Student Research

Ecologists have used integral projection models (IPMs) to study fish and other animals which continue to grow throughout their lives. Such animals cannot shrink, since they have bony skeletons; a mathematical consequence of this is that the kernel of the integral projection operator T is unbounded, and the operator is not compact. A priori, it is unclear whether these IPMs have an asymptotic growth rate λ, or a stable-stage distribution ψ. In the case of a compact operator, these quantities are its spectral radius and the associated eigenvector, respectively. Under biologically reasonable assumptions, we prove that the non-compact operators in …


The Prairie Naturalist, Vol. 52, Issue 2, December 2020 Dec 2020

The Prairie Naturalist, Vol. 52, Issue 2, December 2020

The Prairie Naturalist

Comparing Native Bee Communities on Reconstructed and Remnant Prairie in Missouri • Joseph LaRose, Elisabeth B. Webb, and Deborah Finke

Patterns and Potential Causes of Changing Winter Bird Distributions in South Dakota • David L. Swanson, Reza Goljani Amipkhiz, and Mark D. Dixon

Greater prairie-chickens and sharp-tailed grouse have similarly high nest survival in the Nebraska Sandhills • Larkin A. Powell, Walter H. Schacht, Julia P. Ewalt, and Katie R. McCollum

Captive Ring-necked Pheasant Response to Very High Experimental Doses of Lead • Travis J. Runia and Alex J. Solem

Trends in a Greater Prairie Chicken Population Established by Translocation …


Linking Mosquito Surveillance To Dengue Fever Through Bayesian Mechanistic Modeling, Clinton B. Leach, Jennifer A. Hoeting, Kim M. Pepin, Alvaro E. Eiras, Mevin B. Hooten, Colleen T. Webb Nov 2020

Linking Mosquito Surveillance To Dengue Fever Through Bayesian Mechanistic Modeling, Clinton B. Leach, Jennifer A. Hoeting, Kim M. Pepin, Alvaro E. Eiras, Mevin B. Hooten, Colleen T. Webb

USDA Wildlife Services: Staff Publications

Our ability to effectively prevent the transmission of the dengue virus through targeted control of its vector, Aedes aegypti, depends critically on our understanding of the link between mosquito abundance and human disease risk. Mosquito and clinical surveillance data are widely collected, but linking them requires a modeling framework that accounts for the complex non-linear mechanisms involved in transmission. Most critical are the bottleneck in transmission imposed by mosquito lifespan relative to the virus’ extrinsic incubation period, and the dynamics of human immunity. We developed a differential equation model of dengue transmission and embedded it in a Bayesian hierarchical …


Flowers Are Essential To Maintain High Beetle Diversity (Coleoptera) In A Neotropical Rainforest Canopy, Susan Kirmse, Caroline S. Chaboo Nov 2020

Flowers Are Essential To Maintain High Beetle Diversity (Coleoptera) In A Neotropical Rainforest Canopy, Susan Kirmse, Caroline S. Chaboo

Publications of UNSM Staff and Affiliates

Many hypotheses have been proposed to explain the megadiversity of angiosperms and insects. Flowers and their pollinators represent the most common terrestrial mutualistic interaction today and this is thought to have driven the evolution of angiosperms and their visitors. Within the framework of that interaction, this paper develops and tests two new hypotheses: 1) megadiversity of canopy beetles in tropical rainforests is largely based on flower resources, and 2) the majority of adult canopy beetles are adapted to visit flowers. To test hypothesis 1, the beetle fauna associated with 23 canopy tree species (13 families, 45 individuals) in a 1.4 …


The Birds Of The Nebraska Sandhills, Paul A. Johnsgard, Josef Kren Nov 2020

The Birds Of The Nebraska Sandhills, Paul A. Johnsgard, Josef Kren

Zea E-Books Collection

This book provides basic information on all the species of birds that have been reliably reported from the Nebraska Sandhills region as of 2020. They include 46 permanent residents, 125 summer breeders, 125 migrants, and 102 rare or accidental species, totaling 398 species. Information on status, migration, and habitats is provided for all but the very rare and accidental species. There are also descriptions of 46 refuges, preserves, and other public-access natural areas in the region and seven suggested birding routes. The text contains more than 90,000 words and over 250 literature references along with more than 20 drawings, 9 …


Spotted Owls And Forest Fire: Comment, Gavin M. Jones, R. J. Gutiérrez, William M. Block, Peter C. Carlson, Emily J. Comfort, Samuel A. Cushman, Raymond J. Davis, Stephanie A. Eyes, Alan B. Franklin, Joseph L. Ganey, Shaula Hedwall, John J. Keane, Rodd Kelsey, Damon B, Lesmeister, Malcolm P. North, Susan L. Roberts, Jeremy T. Rockweit, Jamie S. Sanderlin, Sarah C. Sawyer, Ben Solvesky, Douglas J. Tempel, Ho Yi Wan, A. Leroy Westerling, Gary C. White, M. Zachariah Peery Nov 2020

Spotted Owls And Forest Fire: Comment, Gavin M. Jones, R. J. Gutiérrez, William M. Block, Peter C. Carlson, Emily J. Comfort, Samuel A. Cushman, Raymond J. Davis, Stephanie A. Eyes, Alan B. Franklin, Joseph L. Ganey, Shaula Hedwall, John J. Keane, Rodd Kelsey, Damon B, Lesmeister, Malcolm P. North, Susan L. Roberts, Jeremy T. Rockweit, Jamie S. Sanderlin, Sarah C. Sawyer, Ben Solvesky, Douglas J. Tempel, Ho Yi Wan, A. Leroy Westerling, Gary C. White, M. Zachariah Peery

USDA Wildlife Services: Staff Publications

Western North American forest ecosystems are experiencing rapid changes in disturbance regimes because of climate change and land use legacies (Littell et al. 2018). In many of these forests, the accumulation of surface and ladder fuels from a century of fire suppression, coupled with a warming and drying climate, has led to increases in the number of large fires (Westerling 2016) and the proportion of areas burning at higher severity (Safford and Stevens 2017, Singleton et al. 2018). While the annual area burned by fire is still below historical levels (Taylor et al. 2016), some forest types in the west …


Anthropogenic Change On The Distribution Of Marine Megafauna And Their Prey, Baylie Fadool Oct 2020

Anthropogenic Change On The Distribution Of Marine Megafauna And Their Prey, Baylie Fadool

Honors Theses

Anthropogenic change is impacting the distribution and survival of marine megafauna and their prey. Humans are changing every aspect of the marine environment, with effects reaching as large as changing the composition of marine environments to directly overexploiting species through the fishing industry. The role that marine megafauna play in balancing ecosystems, including as top apex predators, leads to detrimental results in the absences and population declines of these species. Migrations and declines due to threats on marine apex predator species will alter their environments by causing mesopredator release and changes in community structure, which is often associated with reduced …


Loci Associated With Antibody Response In Feral Swine (Sus Scrofa) Infected With Brucella Suis, Courtney F. Pierce, Vienna R. Brown, Steven C. Olsen, Paola Boggiatto, Kerri Pedersen, Ryan S. Miller, Scott E. Speidel, Timothy J. Smyser Oct 2020

Loci Associated With Antibody Response In Feral Swine (Sus Scrofa) Infected With Brucella Suis, Courtney F. Pierce, Vienna R. Brown, Steven C. Olsen, Paola Boggiatto, Kerri Pedersen, Ryan S. Miller, Scott E. Speidel, Timothy J. Smyser

USDA Wildlife Services: Staff Publications

Feral swine (Sus scrofa) are a destructive invasive species widespread throughout the United States that disrupt ecosystems, damage crops, and carry pathogens of concern for the health of domestic stock and humans including Brucella suis—the causative organism for swine brucellosis. In domestic swine, brucellosis results in reproductive failure due to abortions and infertility. Contact with infected feral swine poses spillover risks to domestic pigs as well as humans, companion animals, wildlife, and other livestock. Genetic factors influence the outcome of infectious diseases; therefore, genome wide association studies (GWAS) of differential immune responses among feral swine can provide …


A Review Of Avian Influenza A Virus Associations In Synanthropic Birds, Susan A. Shriner, J. Jeffrey Root Oct 2020

A Review Of Avian Influenza A Virus Associations In Synanthropic Birds, Susan A. Shriner, J. Jeffrey Root

USDA Wildlife Services: Staff Publications

Avian influenza A viruses (IAV) have received significant attention due to the threat they pose to human, livestock, and wildlife health. In this review, we focus on what is known about IAV dynamics in less common avian species that may play a role in trafficking IAVs to poultry operations. Specifically, we focus on synanthropic bird species. Synanthropic species, otherwise known as peridomestic, are species that are ecologically associated with humans and anthropogenically modified landscapes, such as agricultural and urban areas. Aquatic birds such as waterfowl and shorebirds are the species most commonly associated with avian IAVs, and are generally considered …


An Open-Sourced, Web-Based Application To Improve Our Ability To Understand Hunter And Angler Purchasing Behavior From License Data, Nathaniel B. Price, Christopher J. Chizinski, Joseph J. Fontaine, Kevin L. Pope, Micaela Rahe, Jeff Rawlinson Oct 2020

An Open-Sourced, Web-Based Application To Improve Our Ability To Understand Hunter And Angler Purchasing Behavior From License Data, Nathaniel B. Price, Christopher J. Chizinski, Joseph J. Fontaine, Kevin L. Pope, Micaela Rahe, Jeff Rawlinson

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

State fish and wildlife agencies rely on hunters and anglers (i.e., sportspersons) to fund management actions through revenue generated from license sales and excise taxes on hunting and fishing equipment. There is a need to develop new techniques that bridge the information gap on participation and provide agencies with an understanding of sportspersons at a resolution that can more directly inform efforts to engage sportspersons. Monitoring sportsperson participation using information about their license-purchasing behavior has the potential to reveal important patterns in recruitment (first-time purchase of a hunting or fishing license), retention (continued purchase of licenses across multiple years), and …


Instability Of Glucocorticoid Metabolites In Coyote Scats: Implications For Field Sampling, Erika T. Stevenson, Eric M. Gese, Lorin A. Neuman-Lee, Susannah S. French Oct 2020

Instability Of Glucocorticoid Metabolites In Coyote Scats: Implications For Field Sampling, Erika T. Stevenson, Eric M. Gese, Lorin A. Neuman-Lee, Susannah S. French

USDA Wildlife Services: Staff Publications

Studying physiologic stress responses can assist in understanding the welfare of animals. One method of measuring the physiologic stress response is evaluating concentrations of glucocorticoid metabolites in feces. Previously, using an adrenocorticotropic hormone challenge, we found fecal glucocorticoid metabolite levels were a reliable indicator of physiologic stress response in coyotes (Canis latrans). We determine whether glucocorticoid metabolite concentrations remain stable when collecting feces over a 2-week period, a timeframe commonly used in scat surveys for wild canids. We collected feces from 6 captive coyotes maintained at the U.S. Department of Agriculture, Wildlife Services, National Wildlife Research Center, Predator …


Tools, Techniques And Teamwork: Transferring New Technologies For Wildlife Management, Conservation And Economic Development, John Eisemann, Gail Keirn Oct 2020

Tools, Techniques And Teamwork: Transferring New Technologies For Wildlife Management, Conservation And Economic Development, John Eisemann, Gail Keirn

USDA Wildlife Services: Staff Publications

Did you ever wonder who invented radio telemetry? Or breakaway snares? What about the bird repellent methyl anthranilate or the livestock protection collar? These and many other tools used in wildlife damage management resulted from creative thinking by biologists, technicians, researchers and managers working to solve complex wildlife issues. Over the past 90 years, these “aha moments” within the U.S. Department of Agriculture’s Wildlife Services program have ranged from developing novel scare devices, traps and vaccines to exploiting an animal’s visual capabilities to stop unwanted behaviors. Once discovered, these unique ideas may lead to practical, feasible and cost-effective wildlife damage …


Agate Fossil Beds National Monument, Paleontological Resources Management Plan (Public Version), Scott Kottkamp, Vincent L. Santucci, Justin S. Tweet, Jessica De Smet, Ellen Stark Sep 2020

Agate Fossil Beds National Monument, Paleontological Resources Management Plan (Public Version), Scott Kottkamp, Vincent L. Santucci, Justin S. Tweet, Jessica De Smet, Ellen Stark

United States National Park Service: Publications

Executive Summary

Since Agate Springs Ranch was founded by James H. Cook in 1887, exquisite examples of transitional Miocene mammalian fauna have been found along this stretch of the Niobrara River valley. Collectively these paleontological discoveries, along with the existing archeological and historical Native American collection, were the basis for establishing Agate Fossil Beds National Monument (AGFO) as a unit of the National Park System (NPS). The fossil remains from the Harrison and Anderson Ranch formations span a short, but important, time period within the Miocene Epoch. AGFO has provided science with an intimate look into North American mammalian evolution …


Vampire Bats: Preparing For Range Expansion Into The U.S., Michael J. Bodenchuk, David L. Bergman Aug 2020

Vampire Bats: Preparing For Range Expansion Into The U.S., Michael J. Bodenchuk, David L. Bergman

USDA Wildlife Services: Staff Publications

The common vampire bat apparently is expanding its range northwards in Mexico and seems poised to enter the southern United States. Climate models predict suitable habitat in the U.S. in south Texas and parts of southern Arizona. While vampire bats’ northward range expansion is not unexpected, the fact that this species brings a strain of rabies that impacts livestock and people warrants a strategic response. Annual economic damages from bats are estimated between $7M and $9M, largely associated with deaths of livestock from rabies. To prepare for the emerging rabies issue, USDA Wildlife Services programs in Texas and Arizona have …


An Evaluation Of Bird And Bat Mortality At Wind Turbines In The Northeastern United States, Daniel Y. Choi, Thomas W. Wittig, Bryan M. Kluever Aug 2020

An Evaluation Of Bird And Bat Mortality At Wind Turbines In The Northeastern United States, Daniel Y. Choi, Thomas W. Wittig, Bryan M. Kluever

USDA Wildlife Services: Staff Publications

Wind energy offers substantial environmental benefits, but wind facilities can negatively impact wildlife, including birds and bats. Researchers and managers have made major efforts to chronicle bird and bat mortality associated with wind facilities, but few studies have examined the patterns and underlying mechanisms of spatial patterns of fatalities at wind facilities. Understanding the horizontal fall distance between a carcass and the nearest turbine pole is important in designing effective search protocols and estimating total mortality. We explored patterns in taxonomic composition and fall distance of bird and bat carcasses at wind facilities in the Northeastern United States using publicly …


Estimation Of Wildlife Damage From Federal Crop Insurance Data, Sophie Mckee, Stephanie A. Shwiff, Aaron M. Anderson Aug 2020

Estimation Of Wildlife Damage From Federal Crop Insurance Data, Sophie Mckee, Stephanie A. Shwiff, Aaron M. Anderson

USDA Wildlife Services: Staff Publications

BACKGROUND: Wildlife damage to crops is a persistent and costly problem for many farmers in the USA. Most existing estimates of crop damage have relied on direct assessment methods such as field studies conducted by trained biologists or surveys distributed to farmers. In this paper, we describe a new method of estimating wildlife damage that exploits federal crop insurance data. We focused our study on four crops: corn, soybean, wheat, and cotton, chosen because of their economic importance and their vulnerability to wildlife damage.

RESULTS: We determined crop-raiding hot spots across the USA over the 2015–2019 period and identified the …


Differences In Soil Water Changes And Canopy Temperature Under Varying Water × Nitrogen Sufficiency For Maize, Tsz Him Lo, Daran Rudnick, Kendall C. Dejonge, Geng Bai, Hope Njuki Nakabuye, Abia Katimbo, Yufeng Ge, Trenton E. Franz, Xin Qiao, Derek M. Heeren Aug 2020

Differences In Soil Water Changes And Canopy Temperature Under Varying Water × Nitrogen Sufficiency For Maize, Tsz Him Lo, Daran Rudnick, Kendall C. Dejonge, Geng Bai, Hope Njuki Nakabuye, Abia Katimbo, Yufeng Ge, Trenton E. Franz, Xin Qiao, Derek M. Heeren

West Central Research and Extension Center, North Platte

Crop nitrogen (N) status is known to affect crop water status and crop water use. To investigate further the N effects on soil water changes and on canopy temperature, three water levels × four N levels were imposed on two growing seasons of maize in west central Nebraska, USA. Soil water changes were measured using a neutron probe, whereas canopy temperature was measured using infrared thermometers on a ground-based mobile platform. At all water levels, soil water losses over monthlong intervals were generally greater as N levels increased. Given equal water levels, early afternoon canopy temperatures were usually lower with …


Spatial Ecology And Resource Selection Of Bighorn Sheep (Ovis Canadensis) Ewes In A Prairie Badlands Population, Erin Wood Jul 2020

Spatial Ecology And Resource Selection Of Bighorn Sheep (Ovis Canadensis) Ewes In A Prairie Badlands Population, Erin Wood

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

The basic spatial ecology and habitat relationships of female bighorn sheep in Nebraska are poorly understood. Establishing seasonal patterns of space use and resource selection for this population at the margin of their historical and current range addresses a key knowledge gap and provides important baseline information for ongoing conservation efforts in Nebraska. We deployed GPS radio-collars on 56 adult ewes in western Nebraska to quantify seasonal space use, movements, and resource selection of ewes. To investigate spatial ecology, we quantified movements of ewes and the factors that influence home range size, seasonal use, and spatial stability across seasons. Home …


Statement Of World Aquatic Scientific Societies On The Need To Take Urgent Action Against Human-Caused Climate Change, Based On Scientific Evidence [Dear Colleague Letter], Scott A. Bonar, Brian R. Murphy, Leanne H. Roulson, Jesse T. Trushenski, Douglas J. Austen, Michael Edward Douglas Jul 2020

Statement Of World Aquatic Scientific Societies On The Need To Take Urgent Action Against Human-Caused Climate Change, Based On Scientific Evidence [Dear Colleague Letter], Scott A. Bonar, Brian R. Murphy, Leanne H. Roulson, Jesse T. Trushenski, Douglas J. Austen, Michael Edward Douglas

United States Fish and Wildlife: Staff Publications

Dear Colleague Letter from the American Fisheries Society to fellow scientific societies, July 25, 2020, about the urgent need for responsive collective action to mitigate impending radical climate change. Includes the Statement of World Aquatic Scientific Societies on the Need to Take Urgent Action Against Human-Caused Climate Change, Based on Scientific Evidence, emphasizing the importance of aquatic ecosystems. Includes extensive citations and notes.

"Water is the most important natural resource on Earth as it is vital for life. Aquatic ecosystems, freshwater or marine, provide multiple benefits to human society, such as provisioning of oxygen, food, drinking water, genetic resources; regulation …


Effects Of Freshwater Crayfish On Influenza A Virus Persistence In Water, J. Jeffrey Root, Jeremy W. Ellis, Susan A. Shriner Jul 2020

Effects Of Freshwater Crayfish On Influenza A Virus Persistence In Water, J. Jeffrey Root, Jeremy W. Ellis, Susan A. Shriner

USDA Wildlife Services: Staff Publications

Several investigations have recently assessed the ability of some aquatic invertebrates to act as tools for avian influenza A virus (IAV) surveillance as well as their potential role(s) in IAV ecology. Because of this, as well as the high IAV seroprevalence rates noted in select mesocarnivores that commonly inhabit aquatic and semi-aquatic habitats, we evaluated the effects that freshwater crayfish have on IAV in water at three dose levels and monitored for the presence of IAV in crayfish tissues (gill and green gland) and haemolymph at multiple time points. At relatively high, medium 432 and low (approximately 10 , 10 …


An Applied Ecology Of Fear Framework: Linking Theory To Conservation Practice, Kaitlyn M. Gaynor, Michael J. Cherry, Sophie L. Gilbert, Michael T. Kohl, Courtney L. Larson, Thomas M. Newsome, Laura R. Prugh, Justin P. Suraci, Julie K. Young, Justine A. Smith Jul 2020

An Applied Ecology Of Fear Framework: Linking Theory To Conservation Practice, Kaitlyn M. Gaynor, Michael J. Cherry, Sophie L. Gilbert, Michael T. Kohl, Courtney L. Larson, Thomas M. Newsome, Laura R. Prugh, Justin P. Suraci, Julie K. Young, Justine A. Smith

USDA Wildlife Services: Staff Publications

Research on the ecology of fear has highlighted the importance of perceived risk from predators and humans in shaping animal behavior and physiology, with potential demographic and ecosystem-wide consequences. Despite recent conceptual advances and potential management implications of the ecology of fear, theory and conservation practices have rarely been linked. Many challenges in animal conservation may be alleviated by actively harnessing or compensating for risk perception and risk avoidance behavior in wild animal populations. Integration of the ecology of fear into conservation and management practice can contribute to the recovery of threatened populations, human–wildlife conflict mitigation, invasive species management, maintenance …


A Survey Of Dairy-Goat Keeping In Zanzibar, Tiffanie Stone, Charles A. Francis, L. O. Eik Jul 2020

A Survey Of Dairy-Goat Keeping In Zanzibar, Tiffanie Stone, Charles A. Francis, L. O. Eik

Department of Agronomy and Horticulture: Faculty Publications

Dairy goats with improved genetics for milk production were recently introduced onto small-scale farms in Zanzibar through governmental and non-governmental projects. These projects were meant to support small-scale farmers by improving both income and household nutrition through milk production. No follow up had been conducted to understand what effects dairy goat keeping had on these small-scale farms, or how they could be improved. A survey of 193 dairy goat farmers in Zanzibar was conducted, including 30% and 60% of all dairy goat farmers on Unguja and Pemba, the two largest islands, respectively. The objective was to understand the impact keeping …


Frontal Vehicle Illumination Via Rear-Facing Lighting Reduces Potential For Collisions With White-Tailed Deer, Travis L. Devault, Thomas W. Seamans, Bradley Blackwell Jul 2020

Frontal Vehicle Illumination Via Rear-Facing Lighting Reduces Potential For Collisions With White-Tailed Deer, Travis L. Devault, Thomas W. Seamans, Bradley Blackwell

USDA Wildlife Services: Staff Publications

nimal–vehicle collisions cause many millions of animal deaths each year worldwide and present a substantial safety risk to people. In the United States and Canada, deer (Odocoileus spp.) are involved in most animal–vehicle collisions associated with human injuries. We evaluated a vehicle-based collision mitigation method designed to decrease the likelihood of deer–vehicle collisions during low-light conditions, when most collisions occur. Specifically, we investigated whether the use of a rear-facing light, providing more complete frontal vehicle illumination than standard headlights alone, enhanced vehicle avoidance behaviors of white-tailed deer (O. virginianus). We quantified flight initiation distance (FID), the likelihood …


Optimal Allocation Of Two Resources In Annual Plants, David Mcmorris Jul 2020

Optimal Allocation Of Two Resources In Annual Plants, David Mcmorris

Department of Mathematics: Dissertations, Theses, and Student Research

The fitness of an annual plant can be thought of as how much fruit is produced by the end of its growing season. Under the assumption that annual plants grow to maximize fitness, we can use techniques from optimal control theory to understand this process. We introduce two models for resource allocation in annual plants which extend classical work by Iwasa and Roughgarden to a case where both carbohydrates and mineral nutrients are allocated to shoots, roots, and fruits in annual plants. In each case, we use optimal control theory to determine the optimal resource allocation strategy for the plant …


Developing Alternatives To Protect Domestic Sheep From Predation In South Africa, David L. Bergman, Nico L. Avenant, Michael J. Bodenchuk, Eddie Steenkamp Jun 2020

Developing Alternatives To Protect Domestic Sheep From Predation In South Africa, David L. Bergman, Nico L. Avenant, Michael J. Bodenchuk, Eddie Steenkamp

USDA Wildlife Services: Staff Publications

South Africa has approximately 8,000 commercial small livestock farms and 5,800 communal/subsistence farmers throughout the country. Reported rates of small livestock loss to predation range from 3-13% and 0.5-19% from communal farming areas. A range of predators exist on the African continent, but in southern Africa major livestock losses are primarily due to black-backed jackal and caracal. South Africans have been managing caracals and jackals for over 300 years with no elimination of predation. During the aforementioned time frame, producers have used and/or developed a number of techniques including lethal, nonlethal, and integrated predator damage management to address predation losses. …


Introduction To The R-Package: Usdampr, Elliott James Dennis, Bowen Chen Jun 2020

Introduction To The R-Package: Usdampr, Elliott James Dennis, Bowen Chen

Extension Farm and Ranch Management News

Why the Need for the Package? In the 1990’s, concern over growing packer concentration and a hog industry market shock resulted in discontent among producers and packers. As a result, the United States Congress passed the Livestock Mandatory Reporting Act of 1999 (1999 Act) [Pub. L. 106-78, Title IX] which is required to be reauthorized every five years. See here for a full history of the Livestock Mandatory Reporting Background.

Market reports were publicly issued in the form of .txt files with varying frequency from April 2000 to April 2020. Current and historical data were also housed in a USDA-AMS …


Soil Chemical Properties After 12 Years Of Tillage And Crop Rotation, Maysoon M. Mikha, Gary Hergert, Xin Qiao, Bijesh Maharjan Jun 2020

Soil Chemical Properties After 12 Years Of Tillage And Crop Rotation, Maysoon M. Mikha, Gary Hergert, Xin Qiao, Bijesh Maharjan

Panhandle Research and Extension Center

Crop rotation in combinationwith tillage can improve productivity, enhance economical return, and reduce soil erosion. The objective of this study was to evaluate the impact of moldboard plow (MP), strip tillage (ST), no-tillage (NT), and crop rotations on: (1) crop yield; (2) soil chemical properties; and (3) particulate organic matter (POM). The study was initiated in 2007 at the University of Nebraska-Lincoln Panhandle Research and Extension Center near Scottsbluff, NE. Crops in rotation were corn (C; Zea mays L.) and dry bean (DB; Phaseolus vulgaris L.) organized in a 3-yr rotation (C–DB–C) and a 4-yr rotation with the addition of …


Vertebrates On The Brink As Indicators Of Biological Annihilation And The Sixth Mass Extinction, Gerardo Ceballos, Paul R. Ehrlich, Peter H. Raven Jun 2020

Vertebrates On The Brink As Indicators Of Biological Annihilation And The Sixth Mass Extinction, Gerardo Ceballos, Paul R. Ehrlich, Peter H. Raven

Harold W. Manter Laboratory: Library Materials

The ongoing sixth mass species extinction is the result of the destruction of component populations leading to eventual extirpation of entire species. Populations and species extinctions have severe implications for society through the degradation of ecosystem services. Here we assess the extinction crisis from a different perspective. We examine 29,400 species of terrestrial vertebrates, and determine which are on the brink of extinction because they have fewer than 1,000 individuals. There are 515 species on the brink (1.7% of the evaluated vertebrates). Around 94% of the populations of 77 mammal and bird species on the brink have been lost in …


The Prairie Naturalist, Vol. 52, Issue 1, June 2020 Jun 2020

The Prairie Naturalist, Vol. 52, Issue 1, June 2020

The Prairie Naturalist

EDITOR’S NOTE • Jane E. Austin, Ph.D., Editor-in-Chief

Factors Associated with Larval Freshwater Drum Annual Peak Density in a Nebraska Irrigation Reservoir • Brett T. Miller, Brian C. Peterson, Keith D. Koupal, and Casey W. Schoenbeck

Small mammal communities in grasslands at the Grand Forks Air Force Base, North Dakota, USA • Lynda R. Lafond, Elizabeth H. Rave, and Kathryn A. Yurkonis

Evaluation of Four Larval Fish Sampling Methods in a Large Midwestern River • Nathan J. Lederman, Anthony R. Sindt, Douglas J. Dieterman, John D. Krenz, and Shannon J. Fisher

Wood Frogs (Rana sylvatica) in Southwestern Roberts …