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Host-Parasite Interactions Within Food Webs, Adam Zvanut Hasik

Graduate Theses and Dissertations

Parasitism is one of the most common life history strategies employed in nature, yet the effects of parasites are often thought to be minimal, and the vast majority of studies fail to consider parasites and their effects on host organisms. This is likely a problem, as the magnitude of parasite-mediated effects on their hosts can be quite large. Additionally, the effects of parasites are known to extend beyond the host to affect other species interactions. I used a series of approaches to gain a more integral understanding of host-parasite interactions by studying (1) the effects of parasites on biotic interactions …

Our Peer The Pigeon: Impacts Of The Covid-19 "Anthropause" On Psu Campus Urban Foragers, Audrey Douglass

University Honors Theses

The 2020 COVID Pandemic presented a paradigm shift dubbed, by some scholars, the 'Anthropause', an ecological epoch in which humans faded from the public sphere. As was the case for many urban species that depend on the foraging of food waste, this meant a fundamental disruption to their food systems and to the entire urban eco-web. The PSU Campus Park Blocks presents a unique opportunity to observe animal behavior, while also a succinct microcosm to study food waste flow changes, and compare species layout to other urban parks in the METRO area. Decreased food waste output from proximal …

Contemporary Challenges And Opportunities For The Management Of Bird Damage At Field Crop Establishment, Christophe Sausse, Alice Baux, Michel Bertrand, Elsa Bonnaud, Sonia Canavelli, Alexandra Destrez, Page E. Klug, Lourdes Olivera, Ethel Rodriguez, Guilllermo Tellechea, Sebastian Zuil

United States Department of Agriculture Wildlife Services: Staff Publications

Bird damage, from sowing to crop establishment, is an important issue for farmers in many parts of the world. However, reliable and cost-effective solutions remain elusive because management tools and research on the subject are limited. The spatial variability of damage across landscapes and the adaptative behaviour of birds create further challenges. Additionally, the issue must be tackled at the landscape scale and involve a variety of stakeholders with conflicting interests and objectives. We summarize some of the challenges and opportunities identified to face these difficulties and address four major research directions for operational solutions including 1) crop damage assessment, …

Spatial Distribution Patterns Of The Populations Of Two Subterranean Termites (Blattodea: Termitidae) In Eucalyptus (Myrtales: Myrtaceae) Plantations, Olaniyi T Alamu, Francis K Ewete, Ayangbade E Ayandokun, John A Ete

Tanzania Journal of Science

The study was conducted in Afaka, Northern Guinea Savanna of Nigeria to determine the spatial distribution patterns of the populations of Ancistrotermes sp. and Microtermes sp. in Eucalyptus camaldulensis Dehnh, Eucalyptus citriodora Hook, Eucalyptus cloeziana F. and Eucalyptus tereticornis Muell plantations. Spatial distributions patterns of the two termite species populations were determined using indices such as ratios of population variance to mean, Lloyd’s index, Green coefficient, Taylor power and Iwao’s regression models. The values of variance to mean ratios, Lloyd’s index and Green coefficient showed that the populations of both termite species had aggregated distribution pattern in all the Eucalyptus …

Lesson Plan - Assessing The Garden Site And Initial Biodiversity Inventory, Center For Urban Resilience

Module 10: Garden Ecology

The purpose of this lesson is to outline how to conduct a site assessment and biodiversity inventory before planting a garden. It is important to assess what is already at the planting site, especially the existing plants, soil composition, amount of sun and shade exposure, the available space, and the water resources available. These elements are limiting factors that will determine the outcome of the garden. Also vital is a biodiversity inventory of the organisms at the site and those that visit the site by soil, land, and air.

As part of the site assessment, students will create a two-dimension …

Addressing Challenges In Aggregating And Analyzing Agroecological Data, Sarah E. Mccord

Open Access Theses & Dissertations

Agroecosystems face multiple threats including land degradation and climate change, changing and competing land uses, invasive species and disease spread, and biodiversity loss. While scientists seek to understand rapidly changing ecosystems, land managers are struggling to maintain ecosystem services amid transitions to novel ecosystem states. Understanding agroecosystem drivers and ensuing responses requires quality information about ecosystems that span biomes, trophic scales, ecological processes, spatiotemporal scales, land use, and land ownership. Yet, using multi-scale agroecosystem information can be frustrating for both scientific researchers and land managers as it is difficult to locate data that are trustworthy, easily accessible, standardized, and connected …

Breeding Ecology And Nest- Site Selection Of Turtle Doves (Streptopelia Turtur) In Three New Orchard Habitats, Thilelli Aitouakli, Ettayib Bensaci

Journal of Bioresource Management

The main aim of our work was to investigate the breeding parameters in three orchard types in Algeria (apple, cherry and nectarine) for better conservation of existing species. A total of 149 active Turtle dove nests were monitored in these man–made agro-systems. Egg laying occurred from early May and continued until mid-August. Egg laying started later in cherry trees and stopped earlier in nectarines. Nest density was higher in apple orchards. Nests were located higher in nectarine. Clutch size was similar among orchard types. Northeast was the dominant orientation in all orchards. Breeding success was higher than that recorded in …

Using Enclosed Y-Mazes To Assess Chemosensory Behavior In Reptiles, M. Rockwell Parker, Andrea F. Currylow, Eric A. Tillman, Charlotte J. Robinson, Jilian M. Josimovich, Isabella M.G. Bukovich, Lauren A. Nazarian, Melia G. Nafus, Bryan M. Kluever, Amy A. Yackel Adams

United States Department of Agriculture Wildlife Services: Staff Publications

Reptiles utilize a variety of environmental cues to inform and drive animal behavior such as chemical scent trails produced by food or conspecifics. Decrypting the scent-trailing behavior of vertebrates, particularly invasive species, enables the discovery of cues that induce exploratory behavior and can aid in the development of valuable basic and applied biological tools. However, pinpointing behaviors dominantly driven by chemical cues versus other competing environmental cues can be challenging. Y-mazes are common tools used in animal behavior research that allow quantification of vertebrate chemosensory behavior across a range of taxa. By reducing external stimuli, Y-mazes remove confounding factors and …

A Comparison Of The Effects Of Ionizing Radiation On Wild Boar Populations In The Chernobyl Exclusion Zone And The Fukushima Exclusion Zone, Victoria Bosch

Senior Theses

Humans are usually evacuated following a nuclear power plant (NPP) accident; however, the wildlife remains in the surrounding area that is blanketed in radionuclides. Despite the known effects of exposure to ionizing radiation on an individual’s health, the effects on wildlife remain unclear. The exclusion zones surrounding the Chernobyl NPP and Fukushima NPP accident sites provide an ideal study system to examine how mammal populations are influenced by chronic, low-dose radiation exposure. The present study examines wild boar abundance and reproductive success in both locations to determine how not only radiation exposure but also the sudden changes in human disturbance …

Unprecedented Migratory Bird Die-Off: A Citizen-Based Analysis On The Spatiotemporal Patterns Of Mass Mortality Events In The Western United States, Di Yang, Anni Yang, Jue Yang, Rongting Xu, Han Qiu

United States Department of Agriculture Wildlife Services: Staff Publications

Extensive, severe wildfires, and wildfire-induced smoke occurred across the western and central United States since August 2020. Wildfires resulting in the loss of habitats and emission of particulate matter and volatile organic compounds pose serious threatens to wildlife and human populations, especially for avian species, the respiratory system of which are sensitive to air pollutions. At the same time, the extreme weather (e.g., snowstorms) in late summer may also impact bird migration by cutting off their food supply and promoting their migration before they were physiologically ready. In this study, we investigated the environmental drivers of massive bird die-offs by …

A Test Of Rad Capture Sequencing On Ethanol-Preserved Centennial And Contemporary Specimens Of Philippine Fishes, Madeleine I. Kenton

Biological Sciences Theses & Dissertations

Understanding the relationship between ecological characteristics and genetic change in natural populations in different time scales can reveal how anthropogenic stressors affect natural populations and can improve the success of conservation strategies. The purpose of the Philippines Partnerships for International Research and Education (PIRE) project is to examine levels of genetic change between historical fish samples collected by the USS Albatross expedition in the early 1900s in the Philippines and contemporary populations collected at the same localities. This study tests genetic protocols to process historical and contemporary DNA for simultaneous comparison. Two DNA library preparation methods, single digest RADseq (“un-baited” …

Microhabitat Selection Of A Sicilian Subterranean Woodlouse And Its Implications For Cave Management, Giuseppe Nicolosi, Stefano Mammola, Salvatore Costanzo, Giorgio Sabella, Rosolino Cirrincione, Giovanni Signorello, Marco Isaia

International Journal of Speleology

Human activities in subterranean environments can affect different ecosystem components, including the resident fauna. Subterranean terrestrial invertebrates are particularly sensitive to environmental change, especially microclimatic variations. For instance, microclimate modifications caused by the visitors may directly affect local fauna in caves opened to the public. However, since numerous factors act synergistically in modulating the distribution and abundance of subterranean species, it remains challenging to differentiate the impact of human intervention from that of other factors. Therefore, evidence of the impact of tourism on cave invertebrate fauna remains scarce. Over a year and with approximately two visits a month, we investigated …

Ecological Studies Of Wolves On Isle Royale Annual Report 2020-2021, John A. Vucetich, Rolf O. Peterson, Sarah R. Hoy

Ecological Studies of Wolves on Isle Royale

Annual Report 2020-2021

Otolith Microchemistry Reveals Low Habitat Connectivity Of California Killifish (Fundulus Parvipinnis) Across A Range Of Spatial Scales, Lisa Robison

Theses

As wetlands face continued fragmentation worldwide, an understanding of habitat connectivity and how fishes that rely on these environments is imperative to conduct effective marine management. Site fidelity and habitat connectivity are vital measures of the interdependence of fish populations living in neighboring marshes (or in regions of a single marsh).

Here, we examine the habitat connectivity, site fidelity, and movement of California killifish (Fundulus parvipinnis) within and among three estuaries in Southern California through otolith microelemental analysis. Assessing the site fidelity of estuarine fishes is important to determine the level of connectivity between spatially distinct populations within …

Abundance, Distribution, And Growth Characteristics Of Three Keystone Vachellia Trees In Gebel Elba National Park, South-Eastern Egypt, Ahmed M. Abbas, Mohammed Al-Kahtani, Stephen J. Novak, Wagdi Saber Soliman

Biology Faculty Publications and Presentations

This study was conducted to evaluate the abundance and distribution pattern of three keystone Vachellia taxa in wadi Khoda and wadi Rahaba, Gebel Elba National Park, a protected area in south-eastern Egypt. These taxa included Vachellia tortilis subsp. tortilis, Vachellia tortilis subsp. raddiana, and Vachellia ehrenbergiana. In wadi Khoda, only two of these taxa were detected (V. tortilis subsp. raddiana and V. tortilis subsp. tortilis), while all three taxa were encountered in wadi Rahaba. The density of trees in wadi Khoda was 34.3 plant ha⁻¹ compared to 26.3 plant ha⁻¹ in …

Understanding Patterns And Functional Impacts Of An Invasive Tree And Its Biological Control In A Riparian System, Annie L. Henry

Electronic Theses and Dissertations

Invasive species have become an inextricable part of the landscape, particularly in riparian plant communities, and removal is often a key component of restoration programs. Biological control (biocontrol) is a method of removal that is often both efficient and effective. However, the impact of biocontrol on target species and indirect effects from invasive species removal can be hard to predict. While monitoring the impact of invasive species removal usually involves some species-based assessment such as changes in diversity, historically dominant species or native species, these strategies do not typically provide insight into the mechanisms underlying plant community response to removal. …

Temporal And Spatial Blood Feeding Patterns Of Urban Mosquitoes In The San Juan Metropolitan Area, Puerto Rico, Matthew W. Hopken, Limarie J. Reyes-Torres, Nicole Scavo, Antoinette J. Piaggio, Zaid Abdo, Daniel Taylor, James Pierce, Donald A. Yee

United States Department of Agriculture Wildlife Services: Staff Publications

Simple Summary: Understanding the biodiversity of urban ecosystems is critical for management of invasive and pest species, conserving native species, and disease control. Mosquitoes (Culicidae) are ubiquitous and abundant in urban ecosystems, and rely on blood meals taken from vertebrates. We used DNA from freshly blood-fed mosquitoes to characterize the diversity of vertebrate host species in the San Juan Metropolitan Area, Puerto Rico. We collected two mosquito species that fed on a variety of vertebrates. Culex quinquefasciatus fed on 17 avian taxa (81.2% of blood meals), seven mammalian taxa (17.9%), and one reptilian taxon (0.85%). Aedes aegypti blood meals were …

Modelling The Factors Affecting The Probability For Local Rabies Elimination By Strategic Control, Johann L. Kotzé, John Duncan Grewar, Aaron M. Anderson

United States Department of Agriculture Wildlife Services: Staff Publications

Dog rabies has been recognized from ancient times and remains widespread across the developing world with an estimated 59,000 people dying annually from the disease. In 2011 a tri-partite alliance consisting of the OIE, the WHO and the FAO committed to globally eliminating dog-mediated human rabies by 2030. Regardless of global support, the responsibility remains with local program managers to implement successful elimination programs. It is well known that vaccination programs have a high probability of successful elimination if they achieve a population-coverage of 70%. It is often quoted that reducing population turnover (typically through sterilizations) raises the probability for …

Continental-Scale Dynamics Of Avian Influenza In U.S. Waterfowl Are Driven By Demography, Migration, And Temperature, Erin E. Gorsich, Colleen T. Webb, Andrew A. Merton, Jennifer A. Hoeting, Ryan S. Miller, Matthew Farnsworth, Seth R. Swafford, Thomas J. Deliberto, Kerri Pedersen, Alan B. Franklin, Robert G. Mclean, Kenneth R. Wilson, Paul Doherty

United States Department of Agriculture Wildlife Services: Staff Publications

Emerging diseases of wildlife origin are increasingly spilling over into humans and domestic animals. Surveillance and risk assessments for transmission between these populations are informed by a mechanistic understanding of the pathogens in wildlife reservoirs. For avian influenza viruses (AIV), much observational and experimental work in wildlife has been conducted at local scales, yet fully understanding their spread and distribution requires assessing the mechanisms acting at both local, (e.g., intrinsic epidemic dynamics), and continental scales, (e.g., long-distance migration). Here, we combined a large, continental-scale data set on low pathogenic, Type A AIV in the United States with a novel network-based …

Characterizing The Host Usage And Development Of Ormia Lineifrons (Diptera: Tachinidae), Kyler J. Rogers

Murray State Theses and Dissertations

Insect communication systems are strongly driven by the evolution of signals or signal preferences. These systems rely on a signaler to truthfully emit signals for receivers to interpret. Often, these signals are conspicuously broadcasted. Conspicuous signals involved in animal communication are intended to attract mates, however, these signals are often exploited by eavesdroppers. Thus, many communication systems experience natural selection and sexual selection acting in opposite directions. New adaptations can arise in response to selective pressures, such as eavesdroppers, leading to co-evolving systems between eavesdroppers and hosts, for example. Understanding these systems can provide valuable insight into how unintended receivers …

Novel Insights To Be Gained From Applying Metacommunity Theory To Long-Term, Spatially Replicated Biodiversity Data, Sydne Record, Nicole M. Voelker, Phoebe L. Zarnetske, Nathan I. Wisnoski, Jonathan D. Tonkin, Christopher Swan, Luca Marazzi, Nina Lany, Thomas Lamy, Ado Compagnoni, Max C. N. Castorani, Riley Andrade, Eric R. Sokol

Biology Faculty Research and Scholarship

Global loss of biodiversity and its associated ecosystem services is occurring at an alarming rate and is predicted to accelerate in the future. Metacommunity theory provides a framework to investigate multi-scale processes that drive change in biodiversity across space and time. Short-term ecological studies across space have progressed our understanding of biodiversity through a metacommunity lens, however, such snapshots in time have been limited in their ability to explain which processes, at which scales, generate observed spatial patterns. Temporal dynamics of metacommunities have been understudied, and large gaps in theory and empirical data have hindered progress in our understanding of …

Quantifying Microbial Resistance To Nematode Predation, Tyler Bacon

Electronic Theses and Dissertations

The selection pressure of predation has encouraged the development of defense traits that can make an individual species more environmentally stable. In addition to biotic pressures, abiotic factors could lead to disruption of predator-prey balance within ecosystems. Consequently, it is significant to better understand how environmental factors can influence predator-prey interactions and how responses may, in turn, affect communities. A current challenge within microbial communities is to understand which intraspecific traits associated with such defense strategies are important for microbial-prey responses to predation, and how the responses vary across environments revealing GxE interactions. In this study, I examined microbial-predator prey …

Patterns Of Dispersion, Movement And Feeding Of The Sea Urchin Lytechinus Variegatus, And The Potential Implications For Grazing Impact On Live Seagrass, Adrianna Parson, Joseph M. Dirnberger, Troy Mutchler

Gulf and Caribbean Research

The sea urchin Lytechinus variegatus is a known grazer of both living and dead tissue of turtlegrass, Thalassia testudinum, occasionally denuding large areas of seagrass. Field studies have attempted to assess effects of herbivory on seagrass by enclosing urchins at various densities. However, it is unclear how unrestricted urchins affect seagrass at lower densities more typically observed in the field. This study describes movement, feeding, and distribution of L. variegatus within beds of T. testudinum in St. Joseph Bay, Florida (USA) to quantify this urchin’s impact as a seagrass grazer. Urchins were absent from portions of seagrass beds closest to …

Applications Of Machine Learning In Microbial Forensics, Ryan B. Ghannam

Dissertations, Master's Theses and Master's Reports

Microbial ecosystems are complex, with hundreds of members interacting with each other and the environment. The intricate and hidden behaviors underlying these interactions make research questions challenging – but can be better understood through machine learning. However, most machine learning that is used in microbiome work is a black box form of investigation, where accurate predictions can be made, but the inner logic behind what is driving prediction is hidden behind nontransparent layers of complexity.

Accordingly, the goal of this dissertation is to provide an interpretable and in-depth machine learning approach to investigate microbial biogeography and to use micro-organisms as …

Sexual Dimorphism Of Thermal Preference In Florida Scrub Lizards (Sceloporus Woodi) And Predicting Response To Climate Change In Two Rare Habitats, Sidney E. Anderson

College of Graduate Studies: Theses & Dissertations

The Florida Scrub Lizard (Sceloporus woodi) is endemic to Florida, where it inhabits fragments of xeric sandhill uplands including endangered long-leaf pine and sand pine scrub habitats. Lizards depend on a predictable range of temperatures to maximize their growth and productivity, and to do so, they shuttle among various thermal micro-environments. Thus, the spatial distribution of temperatures in the habitat is important. Habitats dominated by either high or low extremes of an organism’s preference are energetically costly and dangerous (less optimal), especially to gravid females. This study examines thermal preference of a near-threatened species that also inhabits increasingly rare habitats. …

Evidence On The Effectiveness Of Small Unmanned Aircraft Systems (Suas) As A Survey Tool For North American Terrestrial, Vertebrate Animals: A Systematic Map Protocol, Jared A. Elmore, Michael F. Curran, Kristine O. Evans, Sathishkumar Samiappan, Meilun Zhou, Morgan B. Pfeiffer, Bradley F. Blackwell, Raymond B. Iglay

United States Department of Agriculture Wildlife Services: Staff Publications

Background: Small unmanned aircraft systems (sUAS) are replacing or supplementing manned aircraft and groundbased surveys in many animal monitoring situations due to better coverage at finer spatial and temporal resolutions, access, cost, bias, impacts, safety, efficiency, and logistical benefits. Various sUAS models and sensors are available with varying features and usefulness depending on survey goals. However, justification for selection of sUAS and sensors are not typically offered in published literature and existing reviews do not adequately cover past and current sUAS applications for animal monitoring nor their associated sUAS model and sensor technologies, taxonomic and geographic scope, flight conditions and …

Long-Term Changes In Juvenile Green Turtle Abundance And Foraging Ecology In The Indian River Lagoon, Florida, Christopher Long

Electronic Theses and Dissertations, 2020-2023

Marine turtles are distributed in temperate, sub-tropical and tropical waters and beaches worldwide, often in areas heavily impacted by humans. Although there are many threats to marine turtle populations, the growing threats of nutrient pollution and harmful algal blooms are relatively understudied despite their widespread impacts on coastal marine ecosystems that marine turtles depend on. By studying juvenile green turtles (Chelonia mydas) in the Indian River Lagoon, Florida, where nutrient pollution and HABs are a widespread and longstanding issue, I aimed to conduct a case study of how these threats may affect this federally Threatened species. In Chapter 2, I …

Litter Breakdown And Benthic Invertebrate Detritivores From A Hydrologically Restored Stream, Jacob Becraft

Online Theses and Dissertations

The breakdown of coarse forms of detritus into finer forms is an ecosystem function of forested headwater streams. Many factors influence the rate of litter decay, but there is a lack of research on how stream restorations, that aim to restore hydrologic functions, influence litter breakdown. This study compared litter processing rates and macroinvertebrate detritivore assemblages between a hydrologically restored stream (Slabcamp Creek) and an un-restored control stream (White Pine Branch) in the Daniel Boone National Forest in Rowan Co., KY. Red maple (Acer rubrum) leaves were placed in mesh bags and deployed in riffles and pools at the restored …

Spatial Transferability Of Expert Opinion Models For American Beaver Habitat, Isidro Barela, Leslie M. Burger, Guiming Wang, Kristine O. Evans, Qingmin Meng, Jimmy D. Taylor

United States Department of Agriculture Wildlife Services: Staff Publications

Species distribution models and habitat suitability models (HSMs) have become a popular tool in the conservation of biodiversity. However, the ability to predict species spatial distributions at sites beyond the data source sites (i.e., spatial transferability) is critical for the applications of HSMs in the management and conservation of rare or endangered species. The main objective of our study was to assess the predictive performance and spatial transferability of expert opinion models (EOMs). To build EOMs, we identified through extensive literature reviews 17 key landscape variables to characterize habitat use by American beaver (Castor canadensis). We developed 31 pairwise opinion …

Anthraquinone Repellent Seed Treatment On Corn Reduces Feeding By Wild Pigs, Nathan P. Snow, Joseph M. Halseth, Scott J. Werner, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Wild pigs (Sus scrofa) are a destructive invasive species that cause extensive damage to agriculture throughout many regions of the world. In particular wild pigs damage corn more than any other crop, and most of that damage occurs immediately after planting when wild pigs excavate and consume planted seeds. We evaluated whether anthraquinone (AQ), a repellent, could be useful for protecting seed corn from consumption by wild pigs. Specifically, we conducted cafeteria-style tests at 16 bait sites for 6 nights using concentrations of: untreated, 0.5, 1.5, and 3.0% AQ by weight sprayed on whole-kernel corn in AL and …