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Full-Text Articles in Physical Sciences and Mathematics

Liquid Chromatography Mass Spectrometry Method Development For The Determination Of Β–Defensins In Bovine Milk, Elisha Ogbebor Dec 2023

Liquid Chromatography Mass Spectrometry Method Development For The Determination Of Β–Defensins In Bovine Milk, Elisha Ogbebor

Masters Theses & Specialist Projects

Bovine mastitis is caused by a wide range of pathogens which results in a substantial economic loss for the dairy cattle livestock industry. β-defensins are a part of the innate immune system and act as the first line of defense against mastitis in bovine. β-defensins (~6- 10kDa) are antimicrobial peptides that contain about 28 to 67 amino acids, the presence of six cysteine residues results in their three disulfide bonds and a β-sheet structure. A few β- defensins have been identified in cows based on the site of occurrence and time of expression in tissue, but not in milk. A …


How Beavers (Castor Canadensis) Affect Habitat Availability For Two Native Oregon Turtles: Actinemys Marmorata And Chrysemys Picta Bellii, Rodé Krige Dec 2023

How Beavers (Castor Canadensis) Affect Habitat Availability For Two Native Oregon Turtles: Actinemys Marmorata And Chrysemys Picta Bellii, Rodé Krige

University Honors Theses

Oregon is home to two native freshwater turtle species: the northwestern pond turtle and the western painted turtle. Both turtles are Oregon conservation strategy species with a status rating of sensitive, indicating declining populations. Oregon’s decline in these turtle’s populations is thought to be predominantly due to loss and degradation of habitat that results from development and urbanization. Beavers’ ability to dam streams and create ponds may be creating habitat usable by turtles, but the relationship is under-studied. This study assessed water temperature, basking habitat, and overall turtle habitat suitability at beaver-dammed and control ponds in Portland, Oregon. Average basking …


Pathogenicity In Chickens And Turkeys Of A 2021 United States H5n1 Highly Pathogenic Avian Influenza Clade 2.3.4.4b Wild Bird Virus Compared To Two Previous H5n8 Clade 2.3.4.4 Viruses, Mary J. Pantin-Jackwood, Erica Spackman, Christina Leyson, Sungsu Youk, Scott A. Lee, Linda M. Moon, Mia K. Torchetti, Mary L. Killian, Julianna B. Lenoch, Darrell R. Kapczynski, David E. Swayne, David L. Suarez Nov 2023

Pathogenicity In Chickens And Turkeys Of A 2021 United States H5n1 Highly Pathogenic Avian Influenza Clade 2.3.4.4b Wild Bird Virus Compared To Two Previous H5n8 Clade 2.3.4.4 Viruses, Mary J. Pantin-Jackwood, Erica Spackman, Christina Leyson, Sungsu Youk, Scott A. Lee, Linda M. Moon, Mia K. Torchetti, Mary L. Killian, Julianna B. Lenoch, Darrell R. Kapczynski, David E. Swayne, David L. Suarez

USDA Wildlife Services: Staff Publications

Highly pathogenic avian influenza viruses (HPAIVs) of subtype H5 of the Gs/GD/96 lineage remain a major threat to poultry due to endemicity in wild birds. H5N1 HPAIVs from this lineage were detected in 2021 in the United States (US) and since then have infected many wild and domestic birds. We evaluated the pathobiology of an early US H5N1 HPAIV (clade 2.3.4.4b, 2021) and two H5N8 HPAIVs from previous outbreaks in the US (clade 2.3.4.4c, 2014) and Europe (clade 2.3.4.4b, 2016) in chickens and turkeys. Differences in clinical signs, mean death times (MDTs), and virus transmissibility were found between chickens and …


Raccoon Spatial Ecology In The Rural Southeastern United States, Jacob E. Hill, Madison L. Miller, James L. Helton, Richard B. Chipman, Amy Gilbert, University Of Georgia, Guha Dharmarajan, Olin E. Rhodes Jr. Nov 2023

Raccoon Spatial Ecology In The Rural Southeastern United States, Jacob E. Hill, Madison L. Miller, James L. Helton, Richard B. Chipman, Amy Gilbert, University Of Georgia, Guha Dharmarajan, Olin E. Rhodes Jr.

USDA Wildlife Services: Staff Publications

The movement ecology of raccoons varies widely across habitats with important implications for the management of zoonotic diseases such as rabies. However, the spatial ecology of raccoons remains poorly understood in many regions of the United States, particularly in the southeast. To better understand the spatial ecology of raccoons in the southeastern United States, we investigated the role of sex, season, and habitat on monthly raccoon home range and core area sizes in three common rural habitats (bottomland hardwood, upland pine, and riparian forest) in South Carolina, USA. From 2018–2022, we obtained 264 monthly home ranges from 46 raccoons. Mean …


Baa-Ttling Sore Mouth In Sheep With Mathematical Modeling, David C. Elzinga, W. Christopher Strickland Nov 2023

Baa-Ttling Sore Mouth In Sheep With Mathematical Modeling, David C. Elzinga, W. Christopher Strickland

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


A Mathematical Model Of Acanthocephalan Parasite Infection In Gull-Billed Terns, Charlotte Moser Nov 2023

A Mathematical Model Of Acanthocephalan Parasite Infection In Gull-Billed Terns, Charlotte Moser

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


Precipitation And Greenness In Pastoral Lands Of East Turkana, Kenya, Paul Akpejeluh Nov 2023

Precipitation And Greenness In Pastoral Lands Of East Turkana, Kenya, Paul Akpejeluh

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

Pastoralism has long supported livelihoods and provided essential ecosystem services in landscapes of East Africa. Vegetation productivity is central to the functioning of pastoral systems but may be affected by changes in climate and landuse. Vegetation monitoring is important for understanding the effects of global change in pastoral lands; however, it can be time and resource intensive. Remote sensing provides opportunities for efficient multi-scale monitoring of vegetation and climatic drivers. In this thesis, I explore the utility of satellite and UAV remote sensing for monitoring vegetation and precipitation trends and relationships in the East of Lake Turkana Region of northern …


Skin Lipids Alone Enable Conspecific Tracking In An Invasive Reptile, The Argentine Black And White Tegu Lizard (Salvator Merianae), M. Rockwell Parker, Eric A. Tillman, Lauren A. Nazarian, Megan L. Barlowe, Julianna M. Lincoln, Bryan M. Kluever Oct 2023

Skin Lipids Alone Enable Conspecific Tracking In An Invasive Reptile, The Argentine Black And White Tegu Lizard (Salvator Merianae), M. Rockwell Parker, Eric A. Tillman, Lauren A. Nazarian, Megan L. Barlowe, Julianna M. Lincoln, Bryan M. Kluever

USDA Wildlife Services: Staff Publications

Locating potential mates in non-native habitats is one of the most important challenges faced by invasive vertebrate species. The Argentine black and white tegu lizard (Salvator merianae) is a major invasive reptile species in the contiguous United States and is rapidly expanding its range across Florida and the Southeast, in part due to inadequate management strategies and tools. Because a wide array of reptiles, especially squamates (snakes and lizards), have been well-studied for their reliance on chemical cues to locate conspecifics, our project aimed to isolate chemical cues from tegus and assess the ability of adult males and …


Statistical And Machine Learning Approaches To Describe Factors Affecting Preweaning Mortality Of Piglets, Md Towfiqur Rahman, Tami M. Brown-Brandl, Gary A. Rohrer, Sudhendu R. Sharma, Vamsi Manthena, Yeyin Shi Oct 2023

Statistical And Machine Learning Approaches To Describe Factors Affecting Preweaning Mortality Of Piglets, Md Towfiqur Rahman, Tami M. Brown-Brandl, Gary A. Rohrer, Sudhendu R. Sharma, Vamsi Manthena, Yeyin Shi

Biological Systems Engineering: Papers and Publications

High preweaning mortality (PWM) rates for piglets are a significant concern for the worldwide pork industries, causing economic loss and well-being issues. This study focused on identifying the factors affecting PWM, overlays, and predicting PWM using historical production data with statistical and machine learning models. Data were collected from 1,982 litters from the United States Meat Animal Research Center, Nebraska, over the years 2016 to 2021. Sows were housed in a farrowing building with three rooms, each with 20 farrowing crates, and taken care of by well-trained animal caretakers. A generalized linear model was used to analyze the various sow, …


H5n1 Highly Pathogenic Avian Influenza Clade 2.3.4.4b In Wild And Domestic Birds: Introductions Into The United States And Reassortments, December 2021–April 2022, Sungsu Youk, Mia Kim Torchetti, Kristina Lantz, Julianna B. Lenoch, Mary Lea Killian, Christina Leyson, Sarah N. Bevins, Krista Dilione, Hon S. Ip, David E. Stallknecht, Rebecca L. Poulson, David L. Suarez, David E. Swayne, Mary J. Pantin-Jackwood Oct 2023

H5n1 Highly Pathogenic Avian Influenza Clade 2.3.4.4b In Wild And Domestic Birds: Introductions Into The United States And Reassortments, December 2021–April 2022, Sungsu Youk, Mia Kim Torchetti, Kristina Lantz, Julianna B. Lenoch, Mary Lea Killian, Christina Leyson, Sarah N. Bevins, Krista Dilione, Hon S. Ip, David E. Stallknecht, Rebecca L. Poulson, David L. Suarez, David E. Swayne, Mary J. Pantin-Jackwood

USDA Wildlife Services: Staff Publications

Highly pathogenic avian influenza viruses (HPAIVs) of the A/goose/Guangdong/1/1996 lineage H5 clade 2.3.4.4b continue to have a devastating effect on domestic and wild birds. Full genome sequence analyses using 1369 H5N1 HPAIVs detected in the United States (U.S.) in wild birds, commercial poultry, and backyard flocks from December 2021 to April 2022, showed three phylogenetically distinct H5N1 virus introductions in the U.S. by wild birds. Unreassorted Eurasian genotypes A1 and A2 entered the Northeast Atlantic states, whereas a genetically distinct A3 genotype was detected in Alaska. The A1 genotype spread westward via wild bird migration and reassorted with North American …


Limited Accumulation And Persistence Of An Influenza A Virus In Tadpole Snails (Physa Spp.), Paul T. Oesterle, J. Jeffrey Root, Darcy S.O. Mora, Heather Schneider, Alan B. Franklin, Kathryn P. Huyvaert Oct 2023

Limited Accumulation And Persistence Of An Influenza A Virus In Tadpole Snails (Physa Spp.), Paul T. Oesterle, J. Jeffrey Root, Darcy S.O. Mora, Heather Schneider, Alan B. Franklin, Kathryn P. Huyvaert

USDA Wildlife Services: Staff Publications

Waterfowl infected with avian influenza A viruses (IAVs) shed infectious virus into aquatic environments, providing a mechanism for transmission among waterfowl, while also exposing the entire aquatic ecosystem to the virus. Aquatic invertebrates such as freshwater snails are likely exposed to IAVs in the water column and sediment. Freshwater snails comprise a significant portion of some waterfowl species’ diets, so this trophic interaction may serve as a novel route of IAV transmission. In these experiments, tadpole snails (Physa spp.) were exposed to a low-pathogenicity IAV (H3N8) to determine whether snails can accumulate the virus and, if so, how long virus …


On The Rocks, Below The Rocks: A Study Of Intertidal Life In The Low, Middle And High Zones Of The Puerto Cabuyal – Punta San Clemente Marine Reserve During An El Niño Event, Juliana M. Ferrer Oct 2023

On The Rocks, Below The Rocks: A Study Of Intertidal Life In The Low, Middle And High Zones Of The Puerto Cabuyal – Punta San Clemente Marine Reserve During An El Niño Event, Juliana M. Ferrer

Independent Study Project (ISP) Collection

The rocky intertidal zone is one of the most difficult environments for organisms to survive in due to its harsh biotic and abiotic conditions. As such, it is also one of the best indicators of climate change and an important barrier to beach erosion. This study looked at the rocky intertidal zone of the Puerto Cabuyal-Punta San Clemente Marine Reserve in the Manabí province of Ecuador, with a focus on observing and identifying the organisms found in the area. Data was collected along 30 m transects at varying elevations along the shore using quadrants of two sizes: 50x50 cm for …


Reef Fish Wariness Behavior: Fish Flight Initiation Distance Mediated By Territoriality And Body Size In Three Reef Sites Off The Western Coast Of Isla Colón, Bocas Del Toro, Panamá, Alina G. Irvine Oct 2023

Reef Fish Wariness Behavior: Fish Flight Initiation Distance Mediated By Territoriality And Body Size In Three Reef Sites Off The Western Coast Of Isla Colón, Bocas Del Toro, Panamá, Alina G. Irvine

Independent Study Project (ISP) Collection

Coral reefs are highly productive and diverse underwater ecosystems, providing a variety of environmental services including sand generation, nutrient processing, fish supply, and tourism. However, coral reefs have been increasingly impacted by natural and anthropogenic disturbances, which has negatively affected fish security within their environment. A significant observation is the reduction in evasive behaviors among reef fish in marine reserves compared to those exposed to anthropogenic threats. The present research aims to investigate the factors mediating fish wariness behavior through an exploration of the roles of territoriality and body size on fish flight initiation distance (FID). FID is the distance …


Antiviral Susceptibility Of Clade 2.3.4.4b Highly Pathogenic Avian Influenza A(H5n1) Viruses Isolated From Birds And Mammals In The United States, 2022, Ha T. Nguyen, Anton Chesnokov, Juan De La Cruz, Philippe Noriel Q. Pascua, Vasiliy P. Mishin, Yunho Jang, Joyce Jones, Han Di, Andrei A. Ivashchenko, Mary Lea Killian, Mia K. Torchetti, Kristina Lantz, David E. Wentworth, Charles T. Davis, Alexandre V. Ivachtchenko, Larisa V. Gubareva Sep 2023

Antiviral Susceptibility Of Clade 2.3.4.4b Highly Pathogenic Avian Influenza A(H5n1) Viruses Isolated From Birds And Mammals In The United States, 2022, Ha T. Nguyen, Anton Chesnokov, Juan De La Cruz, Philippe Noriel Q. Pascua, Vasiliy P. Mishin, Yunho Jang, Joyce Jones, Han Di, Andrei A. Ivashchenko, Mary Lea Killian, Mia K. Torchetti, Kristina Lantz, David E. Wentworth, Charles T. Davis, Alexandre V. Ivachtchenko, Larisa V. Gubareva

USDA Wildlife Services: Staff Publications

Clade 2.3.4.4b highly pathogenic avian influenza (HPAI) A(H5N1) viruses that are responsible for devastating outbreaks in birds and mammals pose a potential threat to public health. Here, we evaluated their susceptibility to influenza antivirals. Of 1,015 sequences of HPAI A(H5N1) viruses collected in the United States during 2022, eight viruses (∼0.8%) had a molecular marker of drug resistance to an FDA-approved antiviral: three adamantane-resistant (M2-V27A), four oseltamivir-resistant (NA-H275Y), and one baloxavir-resistant (PA-I38T). Additionally, 31 viruses contained mutations that may reduce susceptibility to inhibitors of neuraminidase (NA) (n = 20) or cap-dependent endonuclease (CEN) (n = 11). A panel of 22 …


A Description Of The Grassland Communities Of The Wildcat Hills Region Of Northwestern Nebraska Including Scotts Bluff National Monument And Rare Plant Survey Of The Wildcat Hills Region Of Northwestern Nebraska, Volume I, Terri Hildebrand, Steven B. Rolfsmeier Aug 2023

A Description Of The Grassland Communities Of The Wildcat Hills Region Of Northwestern Nebraska Including Scotts Bluff National Monument And Rare Plant Survey Of The Wildcat Hills Region Of Northwestern Nebraska, Volume I, Terri Hildebrand, Steven B. Rolfsmeier

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

This study resulted from a Cooperative Agreement between Nebraska Game and Parks Commission and the National Park Service (NPS), with funding provided by the Natural Resource Preservation Program of the NPS. Scotts Bluff National Monument was seeking to characterize the native grassland communities of the Wildcat Hills region in order to develop species composition models for prairie restoration of disturbed lands at the monument. Nebraska Game and Parks Commission needed similar information to refine community classification for the Wildcat Hills region, and to update rare plant species inventories. This report includes a description of the grassland communities and a rare …


A Description Of The Grassland Communities Of The Wildcat Hills Region Of Northwestern Nebraska Including Scotts Bluff National Monument And Rare Plant Survey Of The Wildcat Hills Region Of Northwestern Nebraska, Volume Ii, Terri Hildebrand, Steven B. Rolfsmeier Aug 2023

A Description Of The Grassland Communities Of The Wildcat Hills Region Of Northwestern Nebraska Including Scotts Bluff National Monument And Rare Plant Survey Of The Wildcat Hills Region Of Northwestern Nebraska, Volume Ii, Terri Hildebrand, Steven B. Rolfsmeier

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

This study resulted from a Cooperative Agreement between Nebraska Game and Parks Commission and the National Park Service (NPS), with funding provided by the Natural Resource Preservation Program of the NPS. Scotts Bluff National Monument was seeking to characterize the native grassland communities of the Wildcat Hills region in order to develop species composition models for prairie restoration of disturbed lands at the monument. Nebraska Game and Parks Commission needed similar information to refine community classification for the Wildcat Hills region, and to update rare plant species inventories. This report includes a description of the grassland communities and a rare …


Vegetative Sampling Of The Wildcat Hills Region Of Northwestern Nebraska Including Scotts Bluff National Monument And Rare Plant Survey Of The Wildcat Hills Region Of Northwestern Nebraska, A Final Report To: Nebraska Game And Parks Commission, Terri Hildebrand, Steven B. Rolfsmeier Aug 2023

Vegetative Sampling Of The Wildcat Hills Region Of Northwestern Nebraska Including Scotts Bluff National Monument And Rare Plant Survey Of The Wildcat Hills Region Of Northwestern Nebraska, A Final Report To: Nebraska Game And Parks Commission, Terri Hildebrand, Steven B. Rolfsmeier

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

The Wildcat Hills region of northwestern Nebraska is a ridge extending westerly from Chimney Rock in Morrill county to west of Kiowa Creek in central Scotts Bluff county and southerly into the northernmost portions of Banner county (Fig. 1). Much of the expanse is fronted along its northern portion by the North Platte River and US Highway 26. Also included within the study area are the federal lands of Scotts Bluff National Monument and Chimney Rock National Historic Site. Two large portions of state lands, Wildcat Hills State Recreation Area and Buffalo Creek Wildlife Management Area, are located just easterly …


Freshwater And Saline Flood Plain Wetlands Of The North Platte River - Sources And Seasonal Dynamics: Kiowa Wildlife Management Area, Morrill, Ne, Anne M. Matherne Aug 2023

Freshwater And Saline Flood Plain Wetlands Of The North Platte River - Sources And Seasonal Dynamics: Kiowa Wildlife Management Area, Morrill, Ne, Anne M. Matherne

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

The Kiowa Wildlife Management Area (WMA), a 1 mi² wetland and upland on the North Platte River, was acquired by the Nebraska Game and Parks Commission (NGPC) in 1993. The WMA comprises two distinct wetland types, alkaline and freshwater, both of which provide important wildlife habitat. It was the goal of this project to understand the hydrology controlling the development and maintenance of these wetlands in order to anticipate the affect of management strategies on the wetland complex. The study was designed to develop a comprehensive picture of the hydrogeology of both the fresh and alkaline portions of the WMA, …


Willa Cather Ecological Prairie: An Ecological Overview, Harold G. Nagel Aug 2023

Willa Cather Ecological Prairie: An Ecological Overview, Harold G. Nagel

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

This report includes data gathered on the ecology of a 610 acre mixed grass prairie in south-central Nebraska over a two year period.

An attempt was made to identify as many of the plant and animal species present and to determine density and standing crop biomass wherever possible, under the time and financial constraints present. Few attempts have been made to develop complete species checklists for both animals and plants in prairies. The data collected are considered baseline conditions against which comparisons can be made after a management plan is carried out.

This study of Cather Prairie had several objectives. …


The Flora Of The Oak-Wooded Drainages At The Timber Point Area, Southeastern Butler County, Nebraska, Steven B. Rolfsmeier Aug 2023

The Flora Of The Oak-Wooded Drainages At The Timber Point Area, Southeastern Butler County, Nebraska, Steven B. Rolfsmeier

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

The Timber Point Area is a 160-acre recreational/wildlife area occupying to S½ of the SW¼ sec. 22 and the adjacent N½ of the NW¼ sec. 27, T14N R4E. The area is located in the loess-mantled glacial-till hills of southeast Nebraska not far from the terminal moraine of the Pre-Illinoian glacial sheet, one mile south and two miles east of the present town of Brainard. The uplands at Timber Point were apparently in pasture prior to purchase by the NRD, with some cultivated fields occupying the lower ground along a stream valley which southwest to northeast through the property. This small …


The Flora Of Two Oak Drainages At The Red Cedar Area, Southwestern Saunders County, Nebraska, Steven B. Rolfsmeier Aug 2023

The Flora Of Two Oak Drainages At The Red Cedar Area, Southwestern Saunders County, Nebraska, Steven B. Rolfsmeier

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

The Red Cedar Area is a 175 acre recreational/wildlife area occupying the SE¼ sec. 20, T14N R5E and a small portion of sec. 29 directly to the south. The area is located in the glacial-till hills of southeast Nebraska ca 5 mi. north and 2 mi. west of Valpraiso. The bulk of the area was cultivated farmland prior to purchase by the NRD, and nearly all upland areas here were cultivated cropland, save for some steep oak-wooded drainages on the east side of Hunter’s Slough, which ran northwest to southeast through the property. The creek was dammed after NRD purchase …


The Vascular Plants Of The Woodlands Of South Table Creek In The Vicinity Of The National Arbor Day Center, Nebraska City, Nebraska, Steven B. Rolfsmeier Aug 2023

The Vascular Plants Of The Woodlands Of South Table Creek In The Vicinity Of The National Arbor Day Center, Nebraska City, Nebraska, Steven B. Rolfsmeier

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

The objective of this study is to describe the composition of the vascular plant flora of a three-quarter mile stretch of woodland along South Table Creek managed by the National Arbor Day Foundation in Nebraska City. This 50-60 acre woodland is representative of the many small tributaries of the Missouri River in southeastern Nebraska, and may represent the only natural “preserve” of native forest on the west side of the Missouri River between Fontenelle Forest and Indian Cave State Park. All naturally-occurring species encountered in this study are listed alphabetically by family at the end of this paper, and a …


The Flora Of Meadowlark Prairie, Northeastern Seward County, Nebraska, Steven B. Rolfsmeier Aug 2023

The Flora Of Meadowlark Prairie, Northeastern Seward County, Nebraska, Steven B. Rolfsmeier

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

This report is on the flora of the Meadowlark Prairie. The prairie is an approximately 7 acre remnant of virgin tall-grass prairie in extreme northeastern Seward County, Nebraska. The remnant is triangular in shape and lies on a gentle southeast-facing slope with a total relief of 50 ft., along the east boundary of the Meadowlark Recreation Area. The prairie is surrounded on the east side by a small brome-infested prairie remnant and cultivated field off the NRD property, and on the remaining sides by formerly cultivated fields now seeded to native warm-season grasses. Soils in the area are primarily derived …


The Flora And Plant Communities Of The Ceresco Saline Basins, Southern Saunders County, Nebraska, Steven B. Rolfsmeier Aug 2023

The Flora And Plant Communities Of The Ceresco Saline Basins, Southern Saunders County, Nebraska, Steven B. Rolfsmeier

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

This report is on the flora and plant communities of the Ceresco Saline Basins. The basins are along Rock Creek east of Ceresco and represent the northernmost representatives of the “eastern saline marsh” community in Nebraska. Eastern saline marshland is mostly restricted to the Salt Creek drainage in northern and central Lancaster County, though the Ceresco basins extend a mile or more north into Saunders County in the floodplain of Rock Creek. Some of the wetland in this area is currently under management of the Nebraska Game and Parks Commission, while some of the northernmost portions of the basins are …


Collaborative And Engaged Research To Strengthen Equity And Adaptive Governance In Co-Managed Fisheries, Gabrielle V. Hillyer Aug 2023

Collaborative And Engaged Research To Strengthen Equity And Adaptive Governance In Co-Managed Fisheries, Gabrielle V. Hillyer

Electronic Theses and Dissertations

Small-scale, co-managed fisheries are found throughout the world and often represent intertwining cultures, societies, communities, economies, institutions, and governments. They face complex issues, derived from ecological and social sources. Solving these issues requires diverse expertise, often developed through engaged methodologies which can facilitate collaborative solution creation between researchers, community members, and others. In this dissertation, I demonstrate the benefits of these engaged methodologies and review how they, when coupled with anticolonial approaches to research, can create more equitable solutions to complex issues. This dissertation focuses on multiple projects within the wild clam fishery in Maine including: (1) the creation of …


The Devil You Know And The Devil You Don’T: Current Status And Challenges Of Bovine Tuberculosis Eradication In The United States, Daniel J. O'Brien, Tyler C. Thacker, Liliana C.M. Salvador, Anthony G. Duffiney, Suelee Robbe‑Austerman, Mark S. Camacho, Jason E. Lombard, Mitchell V. Palmer Aug 2023

The Devil You Know And The Devil You Don’T: Current Status And Challenges Of Bovine Tuberculosis Eradication In The United States, Daniel J. O'Brien, Tyler C. Thacker, Liliana C.M. Salvador, Anthony G. Duffiney, Suelee Robbe‑Austerman, Mark S. Camacho, Jason E. Lombard, Mitchell V. Palmer

USDA Wildlife Services: Staff Publications

Having entered into its second century, the eradication program for bovine tuberculosis (bTB, caused by Mycobacterium bovis) in the United States of America occupies a position both enviable and daunting. Excepting four counties in Michigan comprising only 6109 km2 (0.06% of US land area) classified as Modified Accredited, as of April 2022 the entire country was considered Accredited Free of bTB by the US Department of Agriculture for cattle and bison. On the surface, the now well-described circumstances of endemic bTB in Michigan, where white-tailed deer (Odocoileus virginianus) serve as a free-ranging wildlife maintenance host, may appear to be …


Nutrient Dynamics Of Freshwater Estuarine Sediments Disturbed By Dredging, Ryan Allan John Roekle Aug 2023

Nutrient Dynamics Of Freshwater Estuarine Sediments Disturbed By Dredging, Ryan Allan John Roekle

Theses and Dissertations

This study examined the nutrient environment of sediments in the Milwaukee River estuary and the dynamics of those nutrients during simulated disturbance experiments within the context of large-scale dredging remediation. Surface sediments were collected from throughout the Milwaukee estuary (including river, harbor, and nearshore stations) by PONAR, centrifuged to separate porewater (interstitial water) from solid material, and filtered to further isolate and stabilize dissolved material. Porewaters were analyzed for dissolved nutrients including ammoniacal nitrogen (AN), nitrate, nitrite, and soluble reactive phosphorus (SRP). Surface sediment porewaters within the estuary were often highly enriched in AN and SRP, which were often 10-2000x …


New Species Of Dryolestoid From The Late Cretaceous Allen Formation And Implications For South American Faunal Diversity., Brigid Erin Connelly Aug 2023

New Species Of Dryolestoid From The Late Cretaceous Allen Formation And Implications For South American Faunal Diversity., Brigid Erin Connelly

Electronic Theses and Dissertations

Dryolestoids are extinct cladotherians mammals from the Jurassic and Cretaceous periods. I describe a collection of dryolestoid specimens from the Late Cretaceous localities of Cerro Tortuga (Allen Formation), Anfiteatro 1, and Shining (both La Colonia Formation) from Patagonia, Argentina. Using comparative morphology, I identify a new species of meridiolestidan dryolestoid based on eleven specimens across both formations. The new species’ recovery from La Colonia Formation represents the first dryolestoid connection between the two approximately contemporaneous formations. The species’ morphology may represent an ecological shift within Meridiolestida from insectivory to herbivory, showing a transition in characters between the plesiomorphic sharp-toothed meridiolestidans …


Leveraging Eco-Evolutionary Models For Gene Drive Risk Assessment, Matthew A. Combs, Andrew J. Golnar, Justin M. Overcash, Alun L. Lloyd, Keith R. Hayes, David A. O'Brochta, Kim M. Pepin Aug 2023

Leveraging Eco-Evolutionary Models For Gene Drive Risk Assessment, Matthew A. Combs, Andrew J. Golnar, Justin M. Overcash, Alun L. Lloyd, Keith R. Hayes, David A. O'Brochta, Kim M. Pepin

USDA Wildlife Services: Staff Publications

Engineered gene drives create potential for both widespread benefits and irreversible harms to ecosystems. CRISPR-based systems of allelic conversion have rapidly accelerated gene drive research across diverse taxa, putting field trials and their necessary risk assessments on the horizon. Dynamic processbased models provide flexible quantitative platforms to predict gene drive outcomes in the context of system-specific ecological and evolutionary features. Here, we synthesize gene drive dynamic modeling studies to highlight research trends, knowledge gaps, and emergent principles, organized around their genetic, demographic, spatial, environmental, and implementation features. We identify the phenomena that most significantly influence model predictions, discuss limitations of …


A Mechanistic Examination Of Interspecific Competition Between Wild And Domestic Herbivores, Courtney Check Aug 2023

A Mechanistic Examination Of Interspecific Competition Between Wild And Domestic Herbivores, Courtney Check

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Large herbivores, such as mule deer and cattle have similar life histories and likely compete for resources. However, quantifying the extent to which these species compete and the specific resources they compete for has proved challenging. My research examines if cattle influence deer abundance and behavior due to competition for forage, competition for shade, and/or by affecting the predation risk of deer. Using a grid of autonomous trail cameras, I was able to determine if cattle abundance influences local deer abundance in relation to specific resources and habitat features. Using GPS data from collared deer, I was also able to …