Population Biology Commons^™

Effect Of A Near-Zero Magnetic Field On Development And Flight Of Oriental Armyworm (Mythimna Separata), Meng-Meng Yan, Lei Zhang, Yun-Xia Cheng, Thomas W. Sappington, Wei-Dong Pan, Xing-Fu Jiang

Entomology Publications

The geomagnetic field affects all living organisms on the Earth. In this study we investigated the developmental and behavioral effects of rearing Mythimna separata in a near-zero magnetic field (<500 nT) compared to the local geomagnetic field (approximately 50 µT). The near-zero magnetic field produced by a Helmholtz coil system significantly lengthened larval and pupal development durations, increased male longevity, and reduced pupal weight, female reproduction, and the relative expression level of the vitellogenin (Vg) gene in newly emerged females. Moreover, the near-zero magnetic field had a considerable negative effect on the mating ratio of M. separata adults. In addition, the moths in the near-zero magnetic field displayed less flight activity late in the night than those in the Earth's normal geomagnetic field, indicating that the flight rhythm of M. separata may be affected by the near-zero magnetic field. Reduction in magnetic field intensity may have negative effects on the development and flight of oriental armyworm, with consequent additional effects on its migration.

Density Of Free-Roaming Cats Related To Feeding Stations On Hayden Island, Olivia Helback, Joe Liebezeit

University Honors Theses

Free-roaming cats have a devastating impact on wildlife populations with stray/feral cats being the most problematic. In some areas, community members provide these cats with food, water, and shelter often in conjunction with a trap, neuter, return (TNR) program. Hayden Island located north of Portland, Oregon is home to a managed colony of feral and stray cats. Some island residents provide feeding stations for the cats and actively participate in population management. To determine how feeding stations might affect cat spatial distribution, camera traps were placed at 19 different stations in urban and natural areas on Hayden island. Additional ...

208— Describing Genetic Diversity In A Non-Native Ant-Mimicking Spider, Cassidy Mills, Jennifer L. Apple

GREAT Day

The ant-mimicking spider Myrmarachne formicaria (Salticidae) is a species native to Eurasia and was first identified in North America in 2001. It has since been found in many locations in the Northeast including western New York, western Pennsylvania, northeastern Ohio, and southern Ontario. Little is known about its introduction to North America and how it has dispersed since. By characterizing the mitochondrial genetic diversity of this species, we can learn about its introduction history and dispersal patterns in North America. Sequencing of a 600-bp mitochondrial DNA gene region spanning the 16s rRNA, leucine tRNA, and part of the ND1 gene ...

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 ...

Density Dependent Growth Of Pseudomonas Fluorescens In The Presence And Absence Of C. Elegans Predation In Liquid Media, Jack Landmann

Honors Theses

The purpose of this study was to understand the predator-prey relationship between C. elegans worms and P. fluorescens bacteria in liquid media. We were aiming to create a predation model of the relationship between these two species.

This study was performed through three experiments. Using 96-well plates, we were able to measure the change in optical density (OD) of these wells and calculate the growth rate. This growth rate was then graphed and analyzed. The first experiment contained P. fluorescens and KB liquid media, this study demonstrated that the bacterial population has a carrying capacity. We were also able to ...

Population And Evolution Dynamics In Predator-Prey Systems With Anti-Predation Responses, Yang Wang

Electronic Thesis and Dissertation Repository

This thesis studies the impact of anti-predation strategy on the population dynamics of predator-prey interactions. This work includes three research projects.

In the first project, we study a system of delay differential equations by considering both benefit and cost of anti-predation response, as well as a time delay in the transfer of biomass from the prey to the predator after predation. We reveal some insights on how the anti-predation response level and the biomass transfer delay jointly affect the population dynamics; we also show how the nonlinearity in the predation term mediated by the fear effect affects the long term ...

The Effect Of Changing Substrate On Arctic Aquatic Invertebrates Abundance, Tom Dolman

Michael D. Wilson Symposium

Climate change is directly affecting tundra ecosystems in northern regions, and warming temperatures have caused discontinuous permafrost and thawing sediments across the region. This project investigates how increasing erosion and the foraging patterns of migratory snow geese may degrade habitat for aquatic invertebrates in the upper Mast River, located in Wapusk National Park, Manitoba, Canada. In the past two decades, many of the important species of aquatic invertebrates have shown declines. Declining invertebrate populations are predicted to affect aquatic ecosystems and decrease the resources available to shorebirds and waterfowl, which breed and migrate through this area.

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

USDA National Wildlife Research Center - 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 ...

The Insular Herpetofauna Of Mexico: Composition, Conservation, And Biogeographic Patterns, Juan Valentín Pliego‐Sánchez, Christopher Blair, Aníbal H. Díaz De La Vega‐Pérez, Víctor H. Jiménez‐Arcos

Publications and Research

We compile a Mexican insular herpetofaunal checklist to estimate endemism, conservation status, island threats, net taxonomic turnover among six biogeographic provinces belonging to the Nearctic and Neotropical regions, and the relationships between island area and mainland distance versus species richness. We compile a checklist of insular herpetofaunal through performing a literature and collection review. We define the conservation status according to conservation Mexican law, the Red List of International Union for Conservation of Nature, and Environmental Vulnerability Scores. We determine threat percentages on islands according to the 11 major classes of threats to biodiversity. We estimate the net taxonomic turnover ...

Applying Ecological Theory To Amphibian Populations To Determine If Wood Frogs (Lithobates Sylvaticus) Are Ideal And Free When Selecting Breeding Habitat, Taylor M. Braunagel

Masters Theses

Amphibian populations are declining globally due to a litany of factors including pollution, disease, climate change, and most importantly, habitat destruction. As most amphibian life histories involve their populations being recruitment limited, focusing on the mechanism behind breeding habitat selection will reveal useful cues that managers may use to increase abundance and breeding success. Though there are many theoretical models that describe the distribution of animals in response to a resource, the ideal free distribution (IFD) theory has not yet been applied to amphibian settling decisions. Through this application of the IFD, I have found that a population of wood ...

The Effects Of Urbanization On Plant Biodiversity In Southeastern Virginia, Tess Hardesty

Undergraduate Research Symposium

This research project investigated the impacts of urbanization on plant species biodiversity within Southeastern Virginia. The hypothesized results of this research were if there was an increase in urbanization, then plant diversity would decrease. Plant biodiversity can increase the decomposition rates, pollination success, and biomass production of the area. Decreasing in plant biodiversity can increase the spread of pathogens through plant populations and increase herbivore damage. There was data compiled from SERNEC herbarium records of four counties, Accomack, Northampton, Norfolk, and Virginia Beach. Virginia Beach had the largest population increase, which was considered the measurement for urbanization in this study ...

Success Of Glover’S Reef Marine Reserve On Queen Conch (Strombus Gigas) Populations In Belize, Gianna Fanelli, Ciera Jarrett, Sara Joralemon

The Pegasus Review: UCF Undergraduate Research Journal

The queen conch (Strombus gigas) provides important economic, ecological, and societal benefits to local communities throughout the Caribbean. The species, however, has fallen victim to commercial exploitation and overfishing in many areas. In Belize, even with restricted harvesting seasons, size restrictions, and regulations set by the Convention on International Trade in Endangered Species (CITES), harvesting practices have significantly depleted populations. Marine reserves, including the Glover’s Reef Marine Reserve, were established to protect biodiversity and maintain populations of Belize’s natural coral reefs. Utilizing size, frequency, and evidence of harvesting (shell notches), the 2018 Tropical Marine Biology (BSC 3355) course ...

Population Fluctuation And Diurnal Time Budgeting Of White-Headed Duck (Oxyura Leucocephala) During Winter At Garaet Hadj Tahar (Skikda, North East Algerian), Merzoug Seyf Eddine, Abdi Soumia, Bara Mouslim, Houhamdi Moussa

Journal of Bioresource Management

This study was focused on the ecology and behavior of the White-headed Duck (Oxyura leucocephala) at Garaet Hadj Tahar (Guerbes-Sanhadja, North East of Algeria). Sampling was carried out during two wintering seasons (2017-2018 and 2018-2019). High number of this duck was recorded in 2018/19 (350 individuals). We observed two Oxyura population, the first sedentary, and the second, hosted the Garaet during the wintering season. Diurnal time budget was dominated by the comfort activities the sleeping with a rate of 39.13%. Following by swimming (37.76%), feeding (17.59%) grooming (4.58%), courtship ritual (0.56%) and flying (0 ...

Qualitative Analysis Of A Resource Management Model And Its Application To The Past And Future Of Endangered Whale Populations, Glenn Ledder

CODEE Journal

Observed whale dynamics show drastic historical population declines, some of which have not been reversed in spite of restrictions on harvesting. This phenomenon is not explained by traditional predator prey models, but we can do better by using models that incorporate more sophisticated assumptions about consumer-resource interaction. To that end, we derive the Holling type 3 consumption rate model and use it in a one-variable differential equation obtained by treating the predator population in a predator-prey model as a parameter rather than a dynamic variable. The resulting model produces dynamics in which low and high consumption levels lead to single ...

Monitoring For Wolves, Jeff Hansen, Cat Urbigkit

Wildlife Damage Management Technical Series

Gray wolves (Canis lupus) and Mexican wolves (Canis lupus baileyi) once again roam across landscapes where they have been absent for decades (Figure 1). With wolf range expansion comes increased opportunities for conflicts when wolves harass or prey on domestic livestock or other animals. Wolves have relatively high reproductive and dispersal rates but detecting individual animals in low-density populations is difficult without a concerted monitoring effort. In fact, wolf presence in an area often is not known until there is a confirmed livestock depredation. Ranchers and wildlife damage management experts need not wait for livestock depredations to occur before wolves ...

Great Expectations: Deconstructing The Process Pathways Underlying Beaver-Related Restoration, Caroline S. Nash, Gordon E. Grant, Susan Charnley, Jason B. Dunham, Hannah Gosnell, Mark B. Hausner, David S. Pilliod, Jimmy Taylor

USDA National Wildlife Research Center - Staff Publications

Beaver-related restoration is a process-based strategy that seeks to address wide-ranging ecological objectives by reestablishing dam building in degraded stream systems. Although the beaver-related restoration has broad appeal, especially in water-limited systems, its effectiveness is not yet well documented. In this article, we present a process-expectation framework that links beaver-related restoration tactics to commonly expected outcomes by identifying the set of process pathways that must occur to achieve those expected outcomes. We explore the contingency implicit within this framework using social and biophysical data from project and research sites. This analysis reveals that outcomes are often predicated on complex process ...

Toxicity Of Sodium Nitrite-Based Vertebrate Pesticides For European Starlings (Sturnus Vulgaris), Scott J. Werner, Shelagh T. Deliberto, Hailey E. Mclean, Katherine E. Horak, Kirt C. Vercauteren

USDA National Wildlife Research Center - Staff Publications

In the 21st century, invasive animals rank second only to habitat destruction as the greatest threat to global biodiversity. Socially-acceptable and cost-effective strategies are needed to reduce the negative economic and environmental impacts of invasive animals. We investigated the potential for sodium nitrite (SN; CAS 7632-00-0) to serve as an avian toxicant for European starlings (Sturnus vulgaris L.). We also assessed the non-target hazard of an experimental formulation of SN that is being developed as a toxicant for invasive wild pigs (Sus scrofa L.). In gavage experiments with European starlings, we identified a lowest observed adverse effect level (LOAEL) for ...

Sars-Cov-2 Exposure In Escaped Mink, Utah, Usa, Susan A. Shriner, Jeremy W. Ellis, J. Jeffrey Root, Annette Roug, Scott R. Stopak, Gerald W. Wiscomb, Jared R. Zierenberg, Hon S. Ip, Mia Kim Torchetti, Thomas J. Deliberto

USDA National Wildlife Research Center - Staff Publications

In August 2020, outbreaks of coronavirus disease were confirmed on mink farms in Utah, USA. We surveyed mammals captured on and around farms for evidence of infection or exposure. Free-ranging mink, presumed domestic escapees, exhibited high antibody titers, suggesting a potential severe acute respiratory syndrome coronavirus 2 transmission pathway to native wildlife.

We report a wildlife epidemiologic investigation of mammals captured on or near properties in Utah, USA, where outbreaks of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection occurred in farmed mink. Mink farms are relatively common in the United States, and most are small family farms. The US ...

The Influence Of Juvenile Dinosaurs On Community Structure And Diversity, Katlin Schroeder, S. Kathleen Lyons, Felisa A. Smith

Faculty Publications in the Biological Sciences

Despite dominating biodiversity in the Mesozoic, dinosaurs were not speciose. Oviparity constrained even gigantic dinosaurs to less than 15 kg at birth; growth through multiple morphologies led to the consumption of different resources at each stage. Such disparity between neonates and adults could have influenced the structure and diversity of dinosaur communities. Here, we quantified this effect for 43 communities across 136 million years and seven continents. We found that megatheropods (more than 1000 kg) such as tyrannosaurs had specific effects on dinosaur community structure. Although herbivores spanned the body size range, communities with megatheropods lacked carnivores weighing 100 to ...

Impulse Vaccination Model For The Control Of Devil Facial Tumor Disease, Zachary Bobbitt, Timothy Comar, Megan O. Powell, Catherine Roberts, Nicholas Schneider, Teagen Smith

Spora: A Journal of Biomathematics

Devil facial tumor disease (DFTD) is a cancer that affects Tasmanian devils and that has caused the devil population to grossly decline since 1996. We present an SEIVR model to explore if recent advances in DFTD vaccines can help the wild population recover. Considering both and bi-annual impulse of vaccinating wild devils through food drops and introducing vaccinated captive-bred devils into the population, we explore the vaccine efficacy, percent of healthy devils receiving the vaccine, and years of campaign necessary for the devil population to have a long-term recovery. Based on our initial parameter estimations, we find a stable population ...