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The Effects Of Light Level And Temperature On Freshwater Microbial Biomass, Production, Enzyme Activity, And Community Composition, Joel Bonney

Master's Theses and Doctoral Dissertations

Algae can stimulate the production of heterotrophic microbes in periphyton communities, but the synergistic effects of light and temperature on this phenomenon are not well understood and have implications on carbon cycling and energy flow. We employed recirculating mesocosms held at different temperatures and light levels and filled with Typha litter and attached microbes to assess these effects. Heterotrophic microbial production was greater in the presence of light, as were some periphytic enzyme activities. Few response variables increased in a near-linear fashion with ascending temperature, suggesting different temperature optima. The strength of heterotrophic microbial production responses to algal photosynthesis did …

Ires Track I: Usa-China: International Research Experience For Native American Students In Iot-Enabled Environmental Monitoring Technologies., J. Wang, J.M.D. Motschenbacher

School of Natural Resources: Documents and Reviews

No abstract provided.

Mapping Floral Resources For Bees Using Drone Imagery, Arya Massarat

HMC Senior Theses

Poor nutrition among modern day honey bee colonies is contributing to their decline. Yet understanding how the diversity and abundance of flowering species around a colony affects its health remains difficult because of the manual labor required to analyze these large foraging landscapes. We describe a procedure for automatically mapping the species of flowering plants around a colony from overlapping drone images. We developed a pipeline for stitching the images together, identifying plants within them, and classifying each plant by its species. The resulting map of the flowering species surrounding a colony could be used in future experiments that aim …

Adaptive Tolerance To Sodium Chloride In Daphnia Magna, Brady P. Parlato, Rick Kopp

Kentucky Journal of Undergraduate Scholarship

Salinity levels of some freshwater systems have been altered by humans, posing a threat to aquatic life. We hypothesized that a Daphnia magna population pre-treated with a low concentration of NaCl would develop greater salinity tolerance than an untreated population. Two Daphnia magna cultures with 60 individuals each were established, one started with 1.00 ppt NaCl and increased by 0.20 ppt weekly, and the other with pure spring water. After 4 weeks, 40 neonates from each culture were individually placed in a solution of 2.30 ppt NaCl (separately determined to be the LC₅₀) for 48 hours. Survival was …

Landscape Genetics Of Salamander Populations At Mammoth Cave National Park, Jackson Resser

Mahurin Honors College Capstone Experience/Thesis Projects

Habitat connectivity affects the distribution of genetic diversity among populations by influencing the movements of individuals and the resulting pattern of gene flow across landscapes. It has become evident that amphibians are experiencing a period of worldwide population declines brought about by environmental change. An understanding of the effects of habitat structure on landscape connectivity is important for developing effective amphibian conservation strategies. The purpose of this study is to investigate the effect of landscape characteristics on gene flow and population structure of the marbled salamander (Ambystoma opacum) in Mammoth Cave National Park, Kentucky, USA. Salamander larvae were …

Rodent Seed Preference Trials Of Ecologically Important Plants In Kentucky, Katelyn Thomason

Mahurin Honors College Capstone Experience/Thesis Projects

Seed predation is an important ecological process that can affect the success of individual plants and plant populations as a whole. However, seed preferences of herbivores have received little detailed attention in comparison to seedling predation studies (Hulme, 1994). In this project I researched how rodents, specifically their seed preferences, affect the recruitment and survival of ecologically important native plants in Western Kentucky. I used traps to catch Peromyscus leucopus (white-footed mice). Once caught, each mouse was placed in a trial arena with seeds from Silphium perfoliatum (cup plant), Baptisia australis (blue false indigo), Silphium lanciniatum (compass plant), and the …

Morphological Correlates Of Auditory Sensitivity In The Inner Ear Of Two Species Of Invasive Carp, Tyler Patty

Mahurin Honors College Capstone Experience/Thesis Projects

Silver (Hypopthalmichthys molitrix) and bighead (H. nobilis) carp, are invasive species that have negative impacts upon ecosystems. H. molitrix is known to jump completely out of the water in response to broadband sounds, however, this is not observed in H. nobilis. Preliminary experiments reveal that sounds can be used to modify the behavior of carps. Thus, understanding the hearing abilities of these species is important in order to design appropriate acoustical deterrents. Fish heads were preserved in 4% paraformaldehyde and the inner ears dissected and photographed under a light microscope in order to describe the …

Use And Partitioning Of Riparian Corridors By Mammalian Carnivores In Rio Mora National Wildlife Refuge, Armando Toral Becker

Regis University Student Publications (comprehensive collection)

Land conversion across the Southwestern U.S. for agricultural and livestock use and prolonged drought conditions cascade to reduce ecosystem function, including habitat provision for wildlife. Arroyo restoration efforts aim to improve wildlife habitat by decreasing soil erosion and enhancing water retention. These hydrologic and geomorphic changes increase the likelihood that wildlife use restored corridors by increasing riparian vegetation cover. Rio Mora National Wildlife Refuge (RMNWR) has restored several arroyos by installing a system of one-rock dams throughout the refuge, but the extent to which mammals prefer restored over unrestored riparian corridors and how habitat structure influences mammalian use and density …

Size And Density Of Upside-Down Jellyfish, Cassiopea Sp., And Their Impact On Benthic Fluxes In A Caribbean Lagoon, Chester B. Zarnoch, Noshin Hossain, Erika Fusco, Mary Alldred, Timothy J. Hoellein, Sophia Perdikaris

School of Global Integrative Studies: Faculty Publications

Anthropogenic disturbances may be increasing jellyfish populations globally. Epibenthic jellyfish are ideal organisms for studying this phenomenon due to their sessile lifestyle, broad geographic distribution, and prevalence in near-shore coastal environments. There are few studies, however, that have documented epibenthic jellyfish abundance and measured their impact on ecological processes in tropical ecosystems. In this study, the density and size of the upside-down jellyfish (Cassiopea spp.) were measured in Codrington Lagoon, Barbuda. A sediment core incubation study, with and without Cassiopea, also was performed to determine their impact on benthic oxygen and nutrient fluxes. Densities of Cassiopea were 24–168 …

Development Of A Novel Cardiac Ischemia-Reperfusion Model In The Axolotl, Jeremy Tolentino Llaniguez

Wayne State University Dissertations

The Center for Disease Control’s National Center for Health Statistics data for mortality from diseases of the heart show the age-adjusted death rate has fallen from almost 600 deaths in the 1950s to just over 190 deaths per 100,000 U.S. residents today. With the recognized limitations of pharmacotherapy of myocardial infarction (MI), cell-based therapies have been undergoing rapid development and clinical testing. However, there is still no consensus about cell types, delivery routes, dosing and treatment schedules and pretreatment conditioning of cells prior to administration. Furthermore, a fundamental question remains unanswered about the reasons for the poor capacity for myocardial …

Digitized Galapagos Tortoise Whaling Data From 1831-1868, Cyler Norman Conrad, Noah Garwood, James P. Gibbs

Anthropology Datasets

This repository includes a spreadsheet of digitized Galapagos tortoise count data originally transcribed from whaling and sealing logbooks by Charles H. Townsend and published in 1925. Notes are included which describe how the counts were digitized. Data published in Townsend (1925) and digitized here are presented in: Conrad, C. and Gibbs, J.P. (in preparation). Chapter 4: The Era of Exploitation: 1535-1959. In Galapagos Giant Tortoises, Gibbs, James P., Linda J. Cayot and Wacho Tapia (eds.). Elsevier.

The Role Of Mesotocin On Social Bonding In Pinyon Jays, Juan Duque, Tanner Rasmussen, Anna Rodriguez, Jeffrey R. Stevens

Jeffrey Stevens Publications

The neuropeptide oxytocin influences mammalian social bonding by facilitating the building and maintenance of parental, sexual, and same‐sex social relationships. However, we do not know whether the function of the avian homologue mesotocin is evolutionarily conserved across birds. While it does influence avian prosocial behavior, mesotocin's role in avian social bonding remains unclear. Here, we investigated whether mesotocin regulates the formation and maintenance of same‐sex social bonding in pinyon jays (Gymnorhinus cyanocephalus), a member of the crow family. We formed squads of four individually housed birds. In the first, “pair‐formation” phase of the experiment, we repeatedly placed pairs …

Gulls As Sources Of Environmental Contamination By Colistin-Resistant Bacteria, Alan B. Franklin, Andrew M. Ramey, Kevin T. Bentler, Nicole L. Barrett, Loredana M. Mccurdy, Christina A. Ahlstrom, Jonas Bonnedahl, Susan A. Shriner, Jeffrey C. Chandler

United States Department of Agriculture Wildlife Services: Staff Publications

In 2015, the mcr-1 gene was discovered in Escherichia coli in domestic swine in China that conferred resistance to colistin, an antibiotic of last resort used in treating multi-drug resistant bacterial infections in humans. Since then, mcr-1 was found in other human and animal populations, including wild gulls. Because gulls could disseminate the mcr-1 gene, we conducted an experiment to assess whether gulls are readily colonized with mcr-1 positive E. coli, their shedding patterns, transmission among conspecifics, and environmental deposition. Shedding of mcr-1 E. coli by small gull flocks followed a lognormal curve and gulls shed one strain >101 …

Piscivorous Bird Use Of Aquaculture And Natural Water Bodies In Mississippi, Paul C. Burr, Jimmy I. Avery, Garrett M. Street, Bronson K. Strickland, Brian S. Dorr

United States Department of Agriculture Wildlife Services: Staff Publications

Double crested cormorants (Phalacrocorax auritus) and great egrets (Ardea alba) have an extensive history of human wildlife conflict with the aquaculture industry of western Mississippi, USA, due to

their depredation of cultured catfish (Ictalurus spp.). Although aquaculture is abundant, western Mississippi also contains naturally occurring water bodies that offer alternative forage opportunities to these species. How cormorants or egrets distribute themselves among these 2 foraging options is unknown, but it has been generally assumed each species uses aquaculture disproportionately more because of the high density of available prey. To test this assumption, we surveyed these …

Control Or Eradication: Problems In The Management Of Invasive Birds, Michael L. Avery, Chris J. Feare

United States Department of Agriculture Wildlife Services: Staff Publications

Humans have captured, transported and intentionally released wild birds for centuries (Blackburn et al., 2009). Motivations for such purposeful introductions include food (West and Zhou, 2007), religion (Agoramoorthy and Hsu, 2007), sport (McDowall, 1994), biocontrol (Bennett and Hughes, 1959; Kurdila, 1995) and aesthetics (Ryan, 1906; Thomson, 1922). Many purposeful bird introductions were the work of acclimatization societies, particularly in North America, New Zealand and Australia. These societies were formed in the 19th century by European settlers to transport bird species from their homelands in efforts to establish them in the newly settled regions (Thomson, 1922; Dunlap, 1997). As a result …

Biotic And Abiotic Factors Influencing Arsenic Biogeochemistry And Toxicity In Fluvial Ecosystems: A Review, Laura Barral-Fraga, María Teresa Barral, Keeley L. Macneill, Diego Martiñá-Prieto, Soizic Morin, María Carolina Rodríguez-Castro, Baigal-Amar Tuulaikhuu, Helena Guasch

School of Natural Resources: Faculty Publications

This review is focused on the biogeochemistry of arsenic in freshwaters and, especially, on the key role that benthic microalgae and prokaryotic communities from biofilms play together in through speciation, distribution, and cycling. These microorganisms incorporate the dominant iAs (inorganic arsenic) form and may transform it to other arsenic forms through metabolic or detoxifying processes. These transformations have a big impact on the environmental behavior of arsenic because different chemical forms exhibit differences in mobility and toxicity. Moreover, exposure to toxicants may alter the physiology and structure of biofilms, leading to changes in ecosystem function and trophic relations. In this …

Influence Of Burner Position On Temperature Distribution In Soybean Flaming, Miloš Miloš Rajkovic, Goran Malidža, Strahinja Stepanovic, Marko Kostic, Kristina Petrovic

West Central Research and Extension Center, North Platte

The main objective of this study was to identify optimal burner orientation for a newly designed flame cultivator by quantifying the flame temperature distributions of cross, back, and parallel position of burners at different heights of the soybean canopy (distance from the soil surface). Flame temperatures were measured within-row for three burner orientations at seven propane doses (20–100 kg/ha) and eight different canopy heights (0–18 cm above soil surface). Soybean plants in V3 growth stage were flamed with the same doses and burner orientations, and 28 days after treatment (DAT) crop injury (0%–100%), plant height (cm), dry matter (g) and …

Weed Science Research Summary 2020

West Central Research and Extension Center, North Platte

Contents

Assessment of Industrial Hemp Susceptibility to Off-target Movement of Commonly Applied Corn and Soybean Postemergence Herbicides; Milos Zaric, Bruno Canella Vieira, Marija Savic, Barbara Vukoja, Guilherme Sousa Alves, Greg R. Kruger

Effects of Drift-reducing Nozzles and Adjuvants on Dicamba Efficacy; Milos Zaric, Kasey P. Schroeder, Bruno Canella Vieira, Guilherme Sousa Alves, Jesaelen Gizotti de Moraes, Jeffrey A. Golus, Greg R. Kruger

Dicamba Simulated Tank-contamination in Common Postemergence Non-dicamba-tolerant Soybean Herbicide Programs; Milos Zaric, Guilherme Sousa Alves, Bruno Canella Vieira, Jeffrey A. Golus, Greg R. Kruger

Air Induction nozzles pattern distribution influenced by work pressure and boom height; Antonio Augusto …

Planting Date, Cultivar, Seed Treatment, And Seeding Rate Effects On Soybean Growth And Yield, Thandiwe Nleya, Matthew Schutte, David Clay, Graig Reicks, Nathan Mueller

West Central Research and Extension Center, North Platte

Soybean [Glycine max (L.) Merr.] yield is a function of many factors including genetic attributes of the cultivar, environmental conditions, and management practices. Temporally variable weather patterns in North America, especially in the northern Great Plains, have resulted in the re-examination of how spring production practices interact with the environmental conditions to influence yield. This study evaluated the impact of four plantings dates, four seeding rates, and two soybean maturity groups (MGs) using treated and untreated (control) seed on soybean growth, seed yield, and composition. The study was conducted at Volga, SD, in 2014, 2015, and 2016. The planting …

Comparison Of Water-Sensitive Paper, Kromekote And Mylar Collectors For Droplet Deposition With A Visible Fluorescent Dye Solution, J. Connor Ferguson, Andrew J. Hewitt, Chris C. O’Donnell, Greg R. Kruger

West Central Research and Extension Center, North Platte

The study was conducted at the University of Nebraska Pesticide Application and Tech-nology Laboratory in North Platte, Nebraska in July 2015. Two application volume rates (100 and 200 l · ha−1) and three nozzle types (XR, AIXR, TTI) were selected at two flow rates (0.8 and 1.6 l · min−1) and at a single application speed of 7.7 km · h−1. Each collec-tor type [Mylar washed (MW), Mylar image analysis (MIA), water-sensitive paper (WSP), and Kromekote (KK)] was arranged in a randomized complete block design. Each nozzle treatment was replicated twice, providing six cards of each collector type for each …

Herbicide Drift Exposure Leads To Reduced Herbicide Sensitivity In Amaranthus Spp., Bruno Viera, Joe Luck, Keenan Amundsen, Rodrigo Werle, Todd A. Gaines, Greg R. Kruger

West Central Research and Extension Center, North Platte

While the introduction of herbicide tolerant crops provided growers new options to manage weeds, the widespread adoption of these herbicides increased the risk for herbicide spray drift to surrounding vegetation. The impact of herbicide drift in sensitive crops is extensively investigated, whereas scarce information is available on the consequences of herbicide drift in non-target plants. Weeds are often abundant in field margins and ditches surrounding agricultural landscapes. Repeated herbicide drift exposure to weeds could be detrimental to long-term management as numerous weeds evolved herbicide resistance following recurrent-selection with low herbicide rates. The objective of this study was to evaluate if …

The Impact Of Cow Size On Cow–Calf And Postweaning Progeny Performance In The Nebraska Sandhills, Rob L. Ziegler, Jacki A. Musgrave, Tanya L. Meyer, R. Funston, Elliott James Dennis, Kathy Hanford, J. C. Macdonald, Travis Mulliniks

West Central Research and Extension Center, North Platte

Optimizing beef production system efficiency requires an understanding of genetic potential suitable for a given production environment. Therefore, the objective of this retrospective analysis was to determine the influence of cow body weight (BW) adjusted to a common body condition score (BCS) of 5 at weaning-influenced cow-calf performance and postweaning steer and heifer progeny performance. Data were collected at the Gudmundsen Sandhills Laboratory, Whitman, NE, on crossbred, mature cows (n = 1,607) from 2005 to 2017. Cow BCS at calving, prebreeding, and weaning were positively associated (P < 0.01) with greater cow BW. Increasing cow BW was positively associated (P < 0.01) with the percentage of cows that conceived during a 45-d breeding season. For every additional 100-kg increase in cow BW, calf BW increased (P < 0.01) at birth by 2.70 kg and adjusted 205-d weaning BW by 14.76 kg. Calf preweaning average daily gain (ADG) increased (P < 0.01) 0.06 kg/d for every additional 100-kg increase in cow BW. Heifer progeny BW increased (P < 0.01) postweaning with every additional 100-kg increase in dam BW. Dam BW did not influence (P ≥ 0.11) heifer puberty status prior to breeding, overall pregnancy rates, or the percentage of heifers calving in the first 21 d of the calving season. Steer initial feedlot BW increased by 7.20 kg, reimplant BW increased by 10.47 kg, and final BW increased by 10.29 kg (P ≤ 0.01) for every additional 100-kg increase in dam BW. However, steer feedlot ADG was not influenced (P > 0.67) by dam BW. Hot carcass weights of steers were increased (P = …

Diurnal And Seasonal Activity Patterns Of Drosophilid Species (Diptera: Drosophilidae) Present In Blackberry Agroecosystems With A Focus On Spotted-Wing Drosophila, Katharine A. Swoboda-Bhattarai, Hannah Burrack

West Central Research and Extension Center, North Platte

Drosophilid species with different life histories have been shown to exhibit similar behavioral patterns related to locating and utilizing resources such as hosts, mates, and food sources. Drosophila suzukii (Matsumura) is an invasive species that differs from other frugivorous drosophilids in that females lay eggs in ripe and ripening fruits instead of overripe or rotten fruits. We hypothesized that there may be diurnal and/or seasonal patterns associated with the movement of drosophilid species into and out of crop fields and their attraction to fermentation-odor-based monitoring traps, and that D. suzukii would conform to similar patterns. To test these hypotheses, we …

Conspecifics And Familiar Odors Alter Movement Patterns In A Land Snail, Cepaea Hortensis, Madeleine Shelton, Jeeva Rathnaweera, Perri Eason

Undergraduate Arts and Research Showcase

In some animals, unfamiliarity with a place and the presence of a conspecific can change movement patterns, often altering individuals’ routes, exploration, and the directions taken. Patterns such as these can affect individual survival, and thus might be present across a wide range of taxa, although mostly vertebrates have been studied. We used a native Kentucky land snail (white-lipped globe snail, Cepaea hortensis) to investigate how snail size, familiarity and the recent presence of a conspecific affect movement of snails in a novel environment. We also tested whether presence of a familiar smell influenced movement on a 25X25 cm …

Risk Assessment And Flight Decisions In Adult Versus Juvenile Squirrels (Sciurus Carolinensis), Alex Haydon, Jeeva Rathnaweera, Perri Eason

Undergraduate Arts and Research Showcase

One way to quantify a prey’s response to a predator is by flight initiation distance (FID), the distance between a predator and prey at the moment the prey flees. As perceived risk from a predator increases, FID increases. Juvenile animals typically flee from approaching threats sooner than do adults because they have less able risk assessment. However, our observations suggested juvenile squirrels might use a different tactic: foraging near refuges. We first tested whether age affected squirrels’ FID in response to an approaching human on the UofL campus, where squirrels experience high levels of interactions with humans from an early …

Ashfall Fossil Beds: From Waterhole To Rhino Barn, Sandy Mosel

University of Nebraska State Museum: Programs Information

Twelve million years ago a volcanic super-eruption in what is now southwestern Idaho created an enormous ashfall that blanketed the Great Plains with several inches of volcanic ash, devastating the local wildlife. Evidence of this geologic event lies within the hills of the Niobrara River Valley in northeast Nebraska, at a place aptly named the Ashfall Fossil Beds State Historical Park. Located near the tiny village of Royal, the Ashfall Park has been developed around a waterhole where animals succumbed after breathing in the volcanic dust. Buried deeply by windblown volcanic ash in the weeks following the eruption, the skeletons …

Ticks On Lizards: Parasite-Host Interactions Of The Southern Alligator Lizard (Elgaria Multicarinata) In Washington State, Emma Houghton

Undergraduate Honors Theses

I investigated interactions between ectoparasites (ticks) and their host, the southern alligator lizard (Elgaria multicarinata). Alligator lizards are capable of complement-mediated killing of the Lyme disease spirochete carried by ticks and may potentially reduce Lyme disease prevalence by cleansing pathogenic organisms from ticks. Despite this, little is known about host-parasite dynamics in alligator lizards. My goals were to 1) assess patterns of tick presence (i.e. parasite load) on alligator lizards and 2) investigate potential negative effects of ticks on alligator lizards. I sampled lizards during the summer of 2019 near Catherine Creek, along the Columbia River Gorge in southern Washington. …

Investigating The Avian Species Composition, Diversity, And Abundance Of Engelhorn Pond, Kiana Rose

Undergraduate Honors Theses

Central Washington University’s Engelhorn Pond contains important habitats for many organisms, particularly migratory birds, and is a valuable resource for students. However, little information is available about the wildlife inhabiting the pond. The pond’s discrete location means that many people are unaware of its existence. In addition, the pond is threatened by a number of anthropogenic sources, including chemical runoff, garbage, and feral cats. By using point counts, a common ornithological survey technique, I recorded the bird species present at the pond during all seasons of the year. I collected data using point counts during 13 visits from June of …

Ticks On Lizards: Parasite-Host Interactions Of The Southern Alligator Lizard (Elgaria Multicarinata) In Washington State, Emma Houghton

All Undergraduate Projects

I investigated interactions between ectoparasites (ticks) and their host, the southern alligator lizard (Elgaria multicarinata). Alligator lizards are capable of complement-mediated killing of the Lyme disease spirochete carried by ticks and may potentially reduce Lyme disease prevalence by cleansing pathogenic organisms from ticks. Despite this, little is known about host-parasite dynamics in alligator lizards. My goals were to 1) assess patterns of tick presence (i.e. parasite load) on alligator lizards and 2) investigate potential negative effects of ticks on alligator lizards. I sampled lizards during the summer of 2019 near Catherine Creek, along the Columbia River Gorge in southern Washington. …

Genetic Structure Of Green Sea Turtle (Chelonia Mydas) Foraging Aggregations On The East Coast Of Florida, Monica R. Reusche

Honors Undergraduate Theses

The genetic structure of juvenile green turtles (Chelonia mydas) foraging on the east coast of central Florida is not well understood, nor has it been examined over time. In the last three decades, the dramatic increase in the number of green sea turtle nests in Florida, in association with other population parameters, has led to this species being down-listed under the Endangered Species Act from “endangered” to “threatened” in the northwest Atlantic. However, it was unclear if the exponential growth in Florida nest numbers had any influence on the genetic structure of juveniles in nearby foraging aggregations. To …