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Sodium Mediates Developmentally Plastic Responses In Plants And Herbivores, Luis Santiago-Rosario

LSU Doctoral Dissertations

Sodium plays a crucial role in organismal performance, trophic-level interactions, and eco-evolutionary dynamics. For plants, sodium impacts osmoregulation, growth, and water uptake. For animals, sodium is essential influencing osmoregulatory processes, muscle and neural development, and blood regulation. My dissertation aims to disentangle why sodium mismatch affects resource-consumer interactions and its influence on morphological and behavioral plasticity. First, I identified how sodium impacts plant performance and sodium accumulation strategies. I initially focused my research on understanding how increasing substrate sodium affects plant growth and tissue sodium accumulation strategies in controlled settings using a systematic review approach. I found that saltier plants …

Du Undergraduate Showcase: Research, Scholarship, And Creative Works: Abstracts, Emma Aggeler, Elena Arroway, Daisy T. Booker, Justin Bravo, Kyle Bucholtz, Megan Burnham, Nicole Choi, Spencer Cockerell, Rosie Contino, Jackson Garske, Kaitlyn Glover, Caroline Hamilton, Haley Hartmann, Madalyne Heiken, Colin Holter, Leah Huzjak, Alyssa Jeng, Cole Jernigan, Chad Kashiwa, Adelaide Kerenick, Emily King, Abigail Langeberg, Maddie Leake, Meredith Lemons, Alec Mackay, Greer Mckinley, Ori Miller, Guy Milliman, Katherine Miromonti, Audrey Mitchell, Lauren Moak, Megan Morrell, Gelella Nebiyu, Zdenek Otruba, Toni V. Panzera, Kassidy Patarino, Sneha Patil, Alexandra Penney, Kevin Persky, Caitlin Pham, Gabriela Recinos, Mary Ringgenberg, Chase Routt, Olivia Schneider, Roman Shrestha, Arlo Simmerman, Alec Smith, Tessa Smith, Nhi-Lac Thai, Kyle Thurmann, Casey Tindall, Amelia Trembath, Maria Trubetskaya, Zachary Vangelisti, Peter Vo, Abby Walker, David Winter, Grayden Wolfe, Leah York

DU Undergraduate Research Journal Archive

Abstracts from the DU Undergraduate Showcase.

The Spatial Ecology And Habitat Selection Of A Spotted Turtle (Clemmys Guttata) Population In Southwest Michigan, Michela Coury

Masters Theses

Turtles are arguably the most threatened group of vertebrates on the planet. Anthropogenic influences such as habitat loss and fragmentation, road mortality, subsidized predators, climate change, and illegal collection have contributed to their global decline. Understanding which isolated populations of turtles are viable despite these synergistic threats is crucial for making conservation and management decisions. In Michigan, the spotted turtle (Clemmys guttata) is a threatened species subjected to many negative anthropogenic influences that accelerate its rapid population decline. In order to properly sustain their populations, the goal of my research was to investigate relevant factors that help us …

A Test Of Food Partitioning Between The Aquatic Larvae Of Two Parapatric Species Of Two-Lined Salamander (Eurycea Bislineata Species Complex) In A Zone Of Sympatric Contact, Carlos D. Camp, S. Michael Owensby, Emily Benfield, Jessica A. Wooten

Georgia Journal of Science

Phylogenetically related species with similar ecologies often partition resources when in sympatry. Food is an important factor in the co-occurrence of sympatric salamanders, and food partitioning occurs in a variety of sympatric, similar species. Several members of the Two-lined Salamander (Eurycea bislineata) species complex are largely parapatric but co-exist within a narrow zone of sympatric contact. Because larvae of these salamanders frequently occur in very high densities, we tested the hypothesis that larvae of the Blue Ridge Salamander (E. wilderae) and the Southern Two-lined Salamander (E. cirrigera) partition food in sympatry in northeastern Georgia. …

Loggerhead Shrike Detectability And Occurrence In Coastal South Carolina Urban Areas, Michelle Krauser

Electronic Theses and Dissertations

Grassland birds, such as the loggerhead shrike (Lanius ludovicianus), are threatened by extensive land-use change, including urbanization. Loggerhead shrikes have been declining since the early 1900s and are rare or extirpated in portions of their former range. Obtaining reliable population estimates of loggerhead shrikes is important to identify demographic trends and ensure conservation decisions are based on an accurate assessment of their current status. Imperfect detection, or the inability to detect every shrike during a survey, can result in biased population estimates. Estimating detection probability is labor-intensive and requires assumptions that are difficult to satisfy in most field studies. Understanding …

Enzootic Trends Of Crassostrea Virginica And Perkinsus Marinus In North Inlet Estuary, South Carolina, Nico Martin D'Amico

Electronic Theses and Dissertations

The Eastern oyster (Crassostrea virginica) co-occurs with the protozoan parasite Perkinsus marinus (the causative agent for "Dermo") in US Atlantic and Gulf of Mexico estuaries. Oyster host functions as an ecological engineer and agent for benthic-pelagic coupling are compromised when P. marinus infections are common in populations (prevalence) and high in individuals (intensity). P. marinus infections in oysters from North Inlet estuary, South Carolina were quantified in relation to shell height (60-76 mm, ≥76 mm), sex (functional female, male, indeterminate), water temperature, and salinity. Three fringing reefs on a longitudinal transect from the inlet mouth into the watershed were sampled …

Rooting For The Home Team: Arbuscular Mycorrhizas And Root Traits In Native And Invasive Woody Shrubs, Alexander Ebert

Dissertations - ALL

Exotic species invasions present a global issue that is expected to worsen with the extreme conditions brought about by global climate change and anthropogenic disturbance. Invasive plant species in particular exhibit ecological, economic, and cultural effects on contemporary issues such as biodiversity, ecosystem processes and global food security. Understanding the factors governing both the invasion process and the species that become invasive are important tools for lessening the impacts of plant invasion, as well as preventing future invasions. This dissertation focuses on belowground aspects of these invasive species, including linking arbuscular mycorrhizal fungi (AMF) to invader growth responses, investigating the …

A Review Of Current Methods In Avian Dietary Analysis And Their Integrated Application To Characterize The Trophic Niche Of Louisiana Waterthrush (Parkesia Motacilla)., Brandon Hoenig

Electronic Theses and Dissertations

Characterizing a species’ dietary composition presents an avenue to understand many facets of its ecological niche and can provide essential information for the species’ long-term conservation. To date, the vast majority of diet studies have relied on direct identification of prey during foraging observations or from diet samples to characterize the dietary habits of birds. However, advancements in laboratory-based approaches have revolutionized the field of trophic ecology by allowing researchers to indirectly infer dietary habits with higher resolution across greater time scales. Here, I apply two of these laboratory-based techniques, namely DNA metabarcoding and stable isotope analysis, to characterize the …

Review Of Orthochiroides Kovařík, 1998 With Description Of A New Species (Scorpiones: Buthidae), František Kovařík, Graeme Lowe

Euscorpius

The genus Orthochiroides Kovařík, 1998 is reanalyzed. Revised diagnoses and new illustrations for the genus and all four of its species are presented. A new species, O. somalilandus sp. n. from Somaliland is described and illustrated. Phylogenetic relationships of the genus with several other similar genera of small buthids are inferred from a parsimony analysis of 43 discrete morphological characters. The recent synonymy of Orthochiroides with Orthochirus is refuted and the genus is revalidated.

Migration Ecology Of American White Pelicans: Circannual Movement, Geographic Range, And Annual Survival, Ryo Ogawa

Theses and Dissertations

Responses of migratory birds to seasonal climate and long-term environmental changes have been a central theme of avian migration ecology. Atmospheric conditions (e.g., winds and thermals), climate, and land cover and land use (LCLU) are major factors influencing the flights of soaring birds. Soaring American White Pelicans (Pelecanus erythrorhynchos) (hereafter, AWPEs) migrate between the subtropical Gulf of Mexico (GOM) and the temperate Northern Great Plains. American White Pelicans are also economically important piscivorous birds, causing enormous damages to the commercial Channel Catfish (Ictalurus punctatus) aquaculture in the Southeastern US. My studies aimed to evaluate the effects …

Assessing Priority Bird Response To Open Pine Management In Eastern Mississippi, Holly Marie Todaro

Theses and Dissertations

Fire suppression, combined with lack of forest thinning and short-rotation, monodominant management, has drastically altered the landscape in the southeastern U.S., leading to the loss of open pine ecosystems and associated avian species. Management of open pine ecosystems is a common practice; yet, there remains uncertainty regarding how vegetation structure impacts priority species. Using empirical data, I assessed changes in species abundance and associated vegetation characteristics before and after management. I also sought to identify vegetation characteristics that influence home range establishment and microhabitat selection of Bachman’s Sparrows. Priority species were negatively associated with hardwood midstory and abundance per site …

Nesting Ecology Of Wood Ducks And Other Cavity-Nesting Ducks In Mississippi, Justin Taylor Gibson

Theses and Dissertations

Man-made nest boxes are surrogate nest sites widely used by waterfowl managers in North America to propagate free-ranging Wood Ducks (Aix sponsa) and other cavity-nesting waterfowl. I monitored 129 and 174 nest boxes in 2020 and 2021, respectively, at Noxubee National Wildlife Refuge and York Woods, Mississippi. I evaluated site-specific biotic and abiotic factors that were potentially influential on nest survival of Wood Ducks and general nesting ecology and apparent nest success of Black-bellied Whistling Ducks (Dendrocygna autumnalis) and Hooded Mergansers (Lophodytes cucullatus). Daily survival rate of Wood Ducks was negatively influenced by increasing encroaching vegetation at Noxubee NWR and …

Evaluating The Role Of Area, Isolation, And Human Behavior On Meso-Mammals In A Small Statistical Demographic Area, Brittney Palode

Theses and Dissertations

Urbanization offers unique challenges for wildlife. The urban landscape is fragmented and changes available resources for wildlife. Human-dominated landscapes can provide food, shelter, or cover through human-subsidized resources. However, to thrive in human-dominated landscapes, wildlife must adapt or disperse, otherwise they will die. In this study, I investigated how the urban landscape and human behavior influence urban wildlife occurrence. I established 35 camera sites during April 2020. I surveyed residential property dwellers around each camera site to determine what behavior they performed that could increase species occurrence. Gray fox and coyote site use decreased with increased isolation while no species …

Investigation Of Dna Variability And Phylogenetic Relationships Of Perlesta (Plecoptera: Perlidae) In Mississippi, James C. Valentine, Mac H. Alford

Master's Theses

The genus Perlesta Banks, 1906 (Plecoptera: Perlidae) consists of 35 species, 33 native to the United States and Canada and two native to China. For over a century these small, brown stonefly adults and freckled yellow nymphs have gone by the name of the type species of the genus, Perlesta placida, but taxonomic work in the genus since 1989 has resulted in the recognition of additional species. These species were mostly recognized and described using morphological characteristics, but two areas that are lacking include (1) linking nymphs to adults and (2) phylogenetic analysis of all species occurring in Mississippi …

Human Arhgef9 Intellectual Disability Syndrome Is Phenocopied By A Mutation That Disrupts Collybistin Binding To The Gabaa Receptor Α2 Subunit, Dustin J. Hines, April Contreras, Betsua Garcia, Jeffrey S. Barker, Austin J. Boren, Cristelle Moufawad El Achlar, Stephen J. Moss, Rochelle M. Hines

Psychology Faculty Research

Enrichment of collybistin to parvalbumin positive clusters on the soma of pyramidal cells in mouse cortex. Collybistin (green) is strongly enriched at parvalbumin (red) clusters that surround the pyramidal cell soma. Collybistin remains enriched at the parvalbumin clusters on somas in the cortex of Gabra2-1 mice suggesting that collybistin is trafficked to these sites independent of interaction with the α2 subunit of GABAA receptors. For more information, please refer to the article by Hines et al. in this issue.

Urban Habitats Impact The Song And Reproductive Success Of A Migratory Bird, The Gray Catbird (Dumetella Carolinensis), Sasha Ewing

Masters Theses, 2020-current

Urban environments are relatively recent on an evolutionary timescale, and, as such, they create novel selection pressures that may influence fitness and mate choice. Many ecologically significant factors change with increasing levels of urbanization, such as increasing anthropogenic noise, increasing impervious surface, and decreasing forest cover. There is growing empirical evidence that anthropogenic noise affects features of birdsong and, separately, that avian nesting success varies across an urban gradient, but rarely do studies examine both – a necessary step to elucidate the evolutionary potential of these novel pressures. I investigated song features, body morphometrics, and reproductive success in male gray …

Pilfering Passerines? Inter-Class Competition: A New Direction In Foraging Ecology, Shannon Gillen

Masters Theses, 2020-current

Life in the epigeal layer below leaf litterfall often goes unexplored. Shrews (Soricidae, 1910) have foraged in this microhabitat for millions of years, carving out an existence in harsh habitats around the world, ranging from the tropics to subarctic boreal tundra. Two shrew species that inhabit the Shenandoah Valley of Virginia, the least shrew (Cryptotis parva) and northern short-tailed shrew (Blarina brevicauda), were the focus of this study. Shrews make epigeal foraging trails while they continually forage for food, and caching is a way to save this food for times of low and sporadic food availability. …

Identifying Key Stream Restoration Variables In An Agriculturally Impaired Chesapeake Bay Watershed, Julia Portmann

Masters Theses, 2020-current

The Chesapeake Bay watershed spans several states, supports diverse ecosystems, and is crucial to local economies. However, agricultural practices in this region impair water quality. The Smith Creek watershed, within the Shenandoah Valley, was designated a showcase watershed in 2010 by the United States Department of Agriculture to demonstrate the efficacy of implementing restoration projects. We sampled fifteen farms ranging from unrestored to thirty-six years since restoration. At each site, we conducted a kick-net survey for macroinvertebrates, measured canopy cover, algal density, substrate size, and bank height and angle. We identified macroinvertebrates to family and calculated the Chesapeake Basin-wide Index …

Large-Herbivore Nemabiomes: Patterns Of Parasite Diversity And Sharing, Georgia C. Titcomb, Johan Pansu, Matthew C. Hutchinson, Kaia J. Tombak, Christina B. Hansen, Christopher C. M. Baker, Tyler R. Kartzinel, Robert M. Pringle

Publications and Research

Amidst global shifts in the distribution and abundance of wildlife and livestock, we have only a rudimentary understanding of ungulate parasite communities and parasite-sharing patterns. We used qPCR and DNA metabarcoding of fecal samples to characterize gastrointestinal nematode (Strongylida) community composition and sharing among 17 sympatric species of wild and domestic large mammalian herbivore in central Kenya. We tested a suite of hypothesis-driven predictions about the role of host traits and phylogenetic relatedness in describing parasite infections. Host species identity explained 27 – 53% of individual variation in parasite prevalence, richness, community composition and phylogenetic diversity. Host and parasite phylogenies …

Seasonal Variation And Tracking Of Climate Niche Of A Migratory Bird, Javier Gutiérrez Illán, Guiming Wang, D. Tommy King, Fred L. Cunningham

United States Department of Agriculture Wildlife Services: Staff Publications

Migratory birds inhabit different areas during breeding and non-breeding seasons. Depending on the time of the year, they may utilize different resources available in seasonal habitats, but also are subjected to changing climate regimes during their annual life cycle. Migratory birds may adopt ecological niche tracking to cope with different environmental conditions between breeding and non-breeding grounds. The American White Pelican (Pelecanus erythrorhynchos, hereafter ‘AWPE’) is a short-distance migrant between the Gulf of Mexico coastal regions (nonbreeding grounds) and the Northern Great Plains (breeding grounds) of Canada and the US. The American White Pelican is a piscivore, feeding …

Reconstructing The Ecological Relationships Of Late Cretaceous Antarctic Dinosaurs And How Functional Tooth Morphology Influenced These Relationships, Ian D. Broxson

2022 Symposium

The Sandwich Bluff Formation of the James Ross Basin of Antarctica has recently yielded a group of five late Cretaceous dinosaurs that lived contemporaneously with each other, a first for Antarctica. These five dinosaurs include fragmentary remains of two differently sized elasmarian ornithopods, a possible megaraptor, a hadrosaur, and a nodosaur. In this study we will construct a model of the ecological relationships of late Cretaceous Antarctica. Additionally, we will look at what specific factors allowed this group of four herbivores and a carnivore to coexist in a restricted locality and what niches were filled by each species. Methods to …

The Effect Of Different Feeding Regimes On Recent Nutritional And Growth Measurements In Juvenile California Killifish (Fundulus Parvipinnis), Emily Parks

Theses

Gaining a deeper understanding of in-situ growth approximations for juvenile fishes is one way to understand how food consumption may affect fish growth. If variations in growth rate are strongly mirrored by past food status, then the condition (degree of well-being) of fish can be potentially used as a reference for relative prey availability. Furthermore, confirming that there is a positive relationship between food availability and fish growth rate is a critical first step to deepen our understanding of growth rate variation as well as examining if growth can be a proxy for habitat quality.

The California killifish (Fundulus …

Ontogenetic Niche Shift As A Driver Of Community Structure And Diversity In Non-Avian Dinosaurs, Katlin M. Schroeder

Biology ETDs

As some of the most charismatic megafauna to ever walk the earth, the physiology, morphology, growth and evolution of non-avian theropods has been studied exhaustively, yet little is understood about their roles in ecosystems as juveniles. For carnivorous megatheropods, which exceed 1,000kg in mass yet hatched from eggs of limited size, the likelihood of utilizing different prey through ontogeny was high, simply by proxy of the immense difference in size between adults and juveniles. We found these ontogenetic niche shifts, evidenced by significantly different dental microwear in Tyrannosaurids, to have excluded dinosaurian mesocarnivores from Mesozoic communities. The few dinosaurian mesocarnivores …

Developing A Novel Place Preference Assay To Compare Drosophila Species Over Time, Martha M. Brinson

Honors Theses

Across phylogeny, integration of external factors, memory, and internal states of the organism dictate organismal behavior and mechanisms. The underlying genetic components can affect these behaviors such as in genomic changes arising from speciation. In this thesis, a new place preference assay was evaluated in the analysis and investigation of two species of Drosophila flies (D. melanogaster and D. simulans) to measure similarities and differences and their attraction to two different food substrates. Sleep and circadian measurements were also recorded during experimentation. The Drosophila Activity Monitor 5M (DAM5M) System and Sleep Circadian Analysis MATLAB Program (SCAMP) analysis were …

Trophish: Building A Global Database Of Freshwater Trophic Interactions, Jacob M. Ridgway

Honors Thesis

Freshwater management and research frequently use the trophic data of freshwater fishes. Despite this fact, it is difficult to perform a simple search of dietary information for any one fish species. FishBase represents, to our knowledge, the largest compilation of freshwater dietary information to date. However, it excludes a large portion of the ecological literature due to its development taking place prior to the creation of most modern scientific search engines. Our project (TroPhish) is building upon FishBase by digitizing approximately 130 years of data from the fish predation literature. Data from the primary and grey (e.g. theses, dissertations, reports) …

Detection, Occupancy, Abundance, And Mercury Accumulation Of The Alligator Snapping Turtle (Macrochelys Temminckii) In Texas, David Rosenbaum

Electronic Theses and Dissertations

Land use practices and physical alterations of ecosystems result in habitat loss and fragmentation, while chemical alterations, such as pollutant input, reduce habitat quality and health of exposed organisms. Here, I investigated the effects of watershed- and local-scale environmental variables on the occupancy, abundance, and mercury accumulation of a threatened aquatic species (Macrochelys temminckii, i.e., alligator snapping turtle) within the southwestern periphery of its distribution. Hierarchical modeling suggested the distribution of the species is more affected by watershed-scale land-cover than local habitat, and provided a baseline estimate of average species abundance across its range in eastern Texas. Abundance …

Detection And Occurrence Of Nerodia Harteri (Serpentes: Colubridae) In An Upper Portion Of The Brazos River Watershed, Jessica Yates

Electronic Theses and Dissertations

Semiaquatic snakes are disproportionately impacted by habitat alteration adjacent to wetlands because of their reliance on both terrestrial and aquatic habitats. Brazos River Watersnakes, Nerodia harteri, are endemic natricines with one of the most restricted geographic ranges in North America. I quantified detection and site occupancy probabilities of N. harteri and its sympatric congeners (N. erythrogaster and N. rhombifer), as well as microhabitat selection within the Nerodia community. Within occupied transects, search effort was positively correlated with detecting N. harteri, whereas environmental and/or habitat variables were better predictors for detecting the sympatric congeners. Microhabitat selection between …

A Genetic Evaluation Of The Impacts Of Dams On Sauger Movement Patterns In The Arkansas River, Emily R. Jonagan

ATU Theses and Dissertations 2021 - Present

Decreased habitat connectivity as a result of damming can lead to genetic isolation in fish communities, especially in highly migratory species. Sauger Sander canadensis is a migratory freshwater species native to the Arkansas River. Sauger are highly sought after by anglers during their annual spawning migration in late winter. In order to investigate the impacts Arkansas River dams on Sauger populations, fin clips were collected in the winters of 2019, 2020, and 2021 below eight dams in the McClellan-Kerr Arkansas River Navigational System (MKARNS). Fin clips were also collected from two reservoirs in Kansas to serve as distinct reference populations. …

An Application Of Differential Mathematical Modeling Techniques To Study The Ongoing Rabies Epizootic In China, Christopher Turner

Electronic Theses and Dissertations

Rabies remains a global public health issue with a wide variety of neurological symptoms such as confusion, slight paralysis, hypersalivation, and hydrophobia. Rabies is usually fatal once symptoms appear. Many species are reservoirs for rabies, such as foxes, racoons, and wild dogs, which in turn can transmit the disease to humans, leading to complex transmission chains. There is a long latent period of rabies, between 1 to 3 months after infection, which further complicates control efforts. Mathematical modeling is a valuable tool in the study of infectious disease outbreaks and there have been many models applied to rabies outbreaks. However, …

Striped Blenny (Chasmodes Bosquianus) Behavior And Shelter Use In A Southeastern Salt Marsh Tidal Creek, Brooklyn Johnson, Juliana Harding

Honors Theses

Temperate estuaries are important habitats for resident species and maturing juvenile transient fishes. The North Inlet estuary, SC resident fish fauna includes the Striped Blenny (Chasmodes bosquianus) and Crested Blenny (Hypleurochilus geminatus). Individual blenny males occupy habitat shelters year-round. During breeding season, blenny males attract mates to nest and protect developing embryos within the nest. Salinity requirements establish blenny spatial distribution in the estuary. Seasonal spawning activity by these temperate blenny species is related to water temperature and seasonal productivity patterns. Blenny nest site occupancy patterns relative to the lunar cycle, water depth, and salinity were …