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Bouncing Back: Resilience And Its Limits In Late-Age Composing, Louise Wetherbee Phelps Jan 2023

Bouncing Back: Resilience And Its Limits In Late-Age Composing, Louise Wetherbee Phelps

English Faculty Publications

This essay is one of a series on my mother’s late-age composing, studying a writing project she started at age 70 and worked on for more than 25 years. Her intention was to integrate extensive reading, personal experience, and cultural observations to explain changes in parenting (and, by extension, education and enculturation of the next generation) from her childhood in the 1920s through the 2000s. When she died at 97, she left behind a 75-page draft, but was unable to complete her plans for revisions and an ending. I focus here on identifying the multiple factors in the ecology of …


Camera Trap Survey Suggests Forestry And Prescribed Burns Attract Wildlife, But May Not Enhance Diversity, Melissa S. Vilgats, Ryan Ott, Stephanie S. Coster Oct 2021

Camera Trap Survey Suggests Forestry And Prescribed Burns Attract Wildlife, But May Not Enhance Diversity, Melissa S. Vilgats, Ryan Ott, Stephanie S. Coster

Virginia Journal of Science

This study explored whether habitat management techniques such as forest thinning and burning promoted biodiversity. Fifteen camera trap stations were established at Fort A.P. Hill in Bowling Green, VA across forest stands with low, medium, and high basal area. Camera traps were deployed for a total of 532 trap nights, and trap success and species diversity were calculated using Shannon’s index. At each site, the distance to trafficable roadways and water sources, vegetation composition, and the percent groundcover, canopy cover, and understory were measured. The cameras captured nine species and recorded a total of 398 trap events. Linear regression was …


A Test Of Rad Capture Sequencing On Ethanol-Preserved Centennial And Contemporary Specimens Of Philippine Fishes, Madeleine I. Kenton Apr 2021

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” …


Rapid Quantification Of Biofouling With An Inexpensive, Underwater Camera And Image Analysis, Matthew R. First, Scott C. Riley, Kazi Aminul Islam, Victoria Hill, Jiang Li, Richard C. Zimmerman, Lisa A. Drake Jan 2021

Rapid Quantification Of Biofouling With An Inexpensive, Underwater Camera And Image Analysis, Matthew R. First, Scott C. Riley, Kazi Aminul Islam, Victoria Hill, Jiang Li, Richard C. Zimmerman, Lisa A. Drake

Electrical & Computer Engineering Faculty Publications

To reduce the transport of potentially invasive species on ships' submerged surfaces, rapid-and accurate-estimates of biofouling are needed so shipowners and regulators can effectively assess and manage biofouling. This pilot study developed a model approach for that task. First, photographic images were collected in situ with a submersible, inexpensive pocket camera. These images were used to develop image processing algorithms and train machine learning models to classify images containing natural assemblages of fouling organisms. All of the algorithms and models were implemented in a widely available software package (MATLAB©). Initially, an unsupervised clustering model was used, and three …


Diet Of Long-Eared Owl And Common Kestrel In An Urban Landscape (Ukraine), Ivan Zahorodnyi, Oleksii Dubovyk, Ivan Komarnytskyi, Ihor Dykyy Jan 2021

Diet Of Long-Eared Owl And Common Kestrel In An Urban Landscape (Ukraine), Ivan Zahorodnyi, Oleksii Dubovyk, Ivan Komarnytskyi, Ihor Dykyy

Biological Sciences Faculty Publications

In the present study we performed a comparative dietary analysis of two predatory birds, the Long-eared Owl (Asio otus) and the Common Kestrel (Falco tinnunculus) in the district of Lviv city. We found that the Long-eared Owl and the Common Kestrel are typical small mammal specialists within the urban ecosystem. Considering the abundance and biomass of prey, small mammals comprise 98.4% of the Long-eared Owl’s diet. The species composition of mammals coincides almost 50% in the food intake comparison of the two birds. It has been established that the main prey of both species is the …


Spatio-Temporal Modelling Of Tick Life-Stage Count Data With Spatially Varying Coefficients, Thabo Lephoto, Henry Mwambi, Oliver Bodhlyera, Holly Gaff Jan 2021

Spatio-Temporal Modelling Of Tick Life-Stage Count Data With Spatially Varying Coefficients, Thabo Lephoto, Henry Mwambi, Oliver Bodhlyera, Holly Gaff

Biological Sciences Faculty Publications

There is a vast amount of geo-referenced data in many fields of study including ecological studies. Geo-referencing is usually by point referencing; that is, latitudes and longitudes or by areal referencing, which includes districts, counties, states, provinces and other administrative units. The availability of large geo-referenced datasets for modelling has necessitated the development and application of spatial statistical methods. However, spatial varying coefficients models exploring the abundance of tick counts remain limited. In this study we used data that was collected and prepared by researchers in the Department of Biological Sciences from the Old Dominion University, Virginia, USA. We modelled …


Correlates Of Bird Collisions With Buildings Across Three North American Countries, Jared A. Elmore, Stephen B. Hager, Bradley J. Cosentino, Nastasha Hagemeyer, Eric Walters, Scott R. Loss, Et Al. Jan 2020

Correlates Of Bird Collisions With Buildings Across Three North American Countries, Jared A. Elmore, Stephen B. Hager, Bradley J. Cosentino, Nastasha Hagemeyer, Eric Walters, Scott R. Loss, Et Al.

Biological Sciences Faculty Publications

Collisions with buildings cause up to 1 billion bird fatalities annually in North America. Bird-building collisions have recently received increased conservation, research, and policy attention. However, efforts to reduce collisions would benefit from studies conducted at large spatial scales across multiple study sites, with standardized methods, and with consideration of species- and life history-related variation and correlates of collisions. We addressed these research needs with a coordinated data collection effort at 40 sites across North America. We estimated collision vulnerability for 40 bird species by accounting for their North American population abundance, distribution overlap with study sites, and sampling effort. …


A Simple, Inexpensive Method For Mark-Recapture Of Ixodid Ticks, Alexis White, Robin Minch, Lindsey Bidder, Holly Gaff Jan 2020

A Simple, Inexpensive Method For Mark-Recapture Of Ixodid Ticks, Alexis White, Robin Minch, Lindsey Bidder, Holly Gaff

Biological Sciences Faculty Publications

Mark-recapture techniques have been widely used and specialized to study organisms throughout the field of biology. To mark-recapture ticks (Ixodida), we have created a simple method to mark ticks using nail polish applied with an insect pin secured in a pencil that allows for a variety of questions to be answered. For measuring tick control efficacy, estimating population estimates, or measuring movement of ticks, this inexpensive mark-recapture method has been easily applied in the field and in the lab to provide useful data to answer a variety of questions about ticks.


The Natural History Of The Marsh Rice Rat, Oryzomys Palustris, In Eastern Virginia, Robert K. Rose Jan 2020

The Natural History Of The Marsh Rice Rat, Oryzomys Palustris, In Eastern Virginia, Robert K. Rose

Biological Sciences Faculty Publications

The marsh rice rat, Oryzomys palustris, is a common rodent in tidal marshes of eastern Virginia, including those on the barrier islands. It also is present in grassy old fields in upland habitats in the coastal plain and parts of the piedmont of Virginia. This report summarizes what has been learned in recent decades about the population biology of this species in Virginia, including aspects of behavior, density, diet, distribution, genetics, habitats, mammal associates, and reproduction.


Review: Application Of Tick Control Technologies For Blacklegged, Lone Star, And American Dog Ticks, Alexis White, Holly Gaff Jan 2018

Review: Application Of Tick Control Technologies For Blacklegged, Lone Star, And American Dog Ticks, Alexis White, Holly Gaff

Biological Sciences Faculty Publications

Tick population control technologies have been studied for several decades but no method is successful in all situations. The success of each technology depends on tick species identity and abundance, host species identity and abundance, phenology of both ticks and hosts, geographic region, and a multitude of other factors. Here we review current technologies, presenting an overview of each and its effect on three common tick species in the eastern United States: blacklegged ticks (Ixodes scapularis (Say; Ixodida: Ixodidae)), lone star ticks (Amblyomma americanum (Linnaeus; Ixodida: Ixodidae)), and American dog ticks (Dermacentor variabilis (Say; Ixodida: Ixodidae)). Moreover, …


A Synergistic Approach For Evaluating Climate Model Output For Ecological Applications, Rachel D. Cavanagh, Eugene J. Murphy, Thomas J. Bracegirdle, John Turner, Cheryl A. Knowland, Stuart P. Corney, Walker O. Smith Jr., Claire M. Waluda, Nadine M. Johnston, Richard G. J. Bellerby, Eileen E. Hofmann Sep 2017

A Synergistic Approach For Evaluating Climate Model Output For Ecological Applications, Rachel D. Cavanagh, Eugene J. Murphy, Thomas J. Bracegirdle, John Turner, Cheryl A. Knowland, Stuart P. Corney, Walker O. Smith Jr., Claire M. Waluda, Nadine M. Johnston, Richard G. J. Bellerby, Eileen E. Hofmann

CCPO Publications

Increasing concern about the impacts of climate change on ecosystems is prompting ecologists and ecosystem managers to seek reliable projections of physical drivers of change. The use of global climate models in ecology is growing, although drawing ecologically meaningful conclusions can be problematic. The expertise required to access and interpret output from climate and earth system models is hampering progress in utilizing them most effectively to determine the wider implications of climate change. To address this issue, we present a joint approach between climate scientists and ecologists that explores key challenges and opportunities for progress. As an exemplar, our focus …


Factors Influencing Distribution Of Prosthetic Devices In Iran: An Economic Analysis, Sarah Tensen Apr 2017

Factors Influencing Distribution Of Prosthetic Devices In Iran: An Economic Analysis, Sarah Tensen

Virginias Collegiate Honors Council Conference

An estimated 177,622 Iranians have suffered an injury resulting in amputation. Prosthetic devices in Iran are scarce due to wealth disparity, wars, and lack of vital resources. Without prosthetic devices, amputees face unemployment, homelessness, a lowered self-esteem and cannot fully participate in society. I examined economic factors influencing the distribution of prosthetic devices and reviewed articles that focus on healthcare costs, distributions and services, relationships between Iran and other countries, etiology of amputation to find a solution for the prosthetic distribution issues. I concluded issues resulted from high costs, unequal distributions of wealth and resources, unsafe conditions, and a deficit …


Ebola Virus - Epidemiology, Diagnosis, And Control: Threat To Humans, Lessons Learnt, And Preparedness Plans - An Update On Its 40 Year's Journey, Raj Kumar Singh, Kuldeep Dhama, Yashpal Singh Malik, Muthannan Andavar Ramakrishnan, Kumaragurubaran Karthik, Rekha Khandia, Ruchi Tiwari, Ashok Munjal, Mani Saminathan, Perumal Arumugam, Sunil Kumar Joshi Apr 2017

Ebola Virus - Epidemiology, Diagnosis, And Control: Threat To Humans, Lessons Learnt, And Preparedness Plans - An Update On Its 40 Year's Journey, Raj Kumar Singh, Kuldeep Dhama, Yashpal Singh Malik, Muthannan Andavar Ramakrishnan, Kumaragurubaran Karthik, Rekha Khandia, Ruchi Tiwari, Ashok Munjal, Mani Saminathan, Perumal Arumugam, Sunil Kumar Joshi

Bioelectrics Publications

Ebola virus (EBOV) is an extremely contagious pathogen and causes lethal hemorrhagic fever disease in man and animals. The recently occurred Ebola virus disease (EVD) outbreaks in the West African countries have categorized it as an international health concern. For the virus maintenance and transmission, the non-human primates and reservoir hosts like fruit bats have played a vital role. For curbing the disease timely, we need effective therapeutics/prophylactics, however, in the absence of any approved vaccine, timely diagnosis and monitoring of EBOV remains of utmost importance. The technologically advanced vaccines like a viral-vectored vaccine, DNA vaccine and virus-like particles are …


Poster Session, Honors College, Odu Feb 2017

Poster Session, Honors College, Odu

Undergraduate Research Symposium

No abstract provided.


2017 Undergraduate Research Symposium: Full Program, Honors College, Old Dominion University Feb 2017

2017 Undergraduate Research Symposium: Full Program, Honors College, Old Dominion University

Undergraduate Research Symposium

Full program with schedule and abstracts for the 2017 Undergraduate Research Symposium.


Beyond Zar: The Use And Abuse Of Classification Statistics For Otolith Chemistry, C. M. Jones, M. Palmers, J. J. Schaffler Jan 2017

Beyond Zar: The Use And Abuse Of Classification Statistics For Otolith Chemistry, C. M. Jones, M. Palmers, J. J. Schaffler

OES Faculty Publications

Classification method performance was evaluated using otolith chemistry of juvenile Atlantic menhaden Brevoortia tyrannus when assumptions of data normality were met and were violated. Four methods were tested [linear discriminant function analysis (LDFA), quadratic discriminant function analysis (QDFA), random forest (RF) and artificial neural networks (ANN)] using computer simulation to determine their performance when variable-group means ranged from small to large and their performance under conditions of typical skewness to double the amount of skewness typically observed. Using the kappa index, the parametric methods performed best after applying appropriate data transformation, gaining 2% better performance with LDFA performing slightly better …


Making The Case For Place: An Exploration Of Urbanization Measures On A Model Of Social Capital And U.K. Crime Rates, Kyshawn K. Smith Jul 2016

Making The Case For Place: An Exploration Of Urbanization Measures On A Model Of Social Capital And U.K. Crime Rates, Kyshawn K. Smith

Sociology & Criminal Justice Theses & Dissertations

Studies of social capital and crime have become quite popular in recent history, and a plethora of empirical tests have sought to clarify relationships between the two variables. However, most of these studies center on communities in the United States, and often overlook the many differentiating features between urban and rural communities that would affect such models. Reasons offered for such skew in the past and current research on this subject are middling at best, and largely cite either a lack of availability in data for crime and social capital in non-urban communities, or questionable accuracy for what data is …


Geospatial Approaches To Support Pelagic Conservation Planning And Adaptive Management, L. M. Wedding, Sara M. Maxwell, D. Hyrenbach, D. C. Dunn, J. J. Roberts, D. Briscoe, E. Hines, P. N. Halpin Jan 2016

Geospatial Approaches To Support Pelagic Conservation Planning And Adaptive Management, L. M. Wedding, Sara M. Maxwell, D. Hyrenbach, D. C. Dunn, J. J. Roberts, D. Briscoe, E. Hines, P. N. Halpin

Biological Sciences Faculty Publications

Place-based management in the open ocean faces unique challenges in delineating boundaries around temporally and spatially dynamic systems that span broad geographic scales and multiple management jurisdictions, especially in the 'high seas'. Geospatial technologies are critical for the successful design of pelagic conservation areas, because they provide information on the spatially and temporally dynamic oceanographic features responsible for driving species distribution and abundance in the open ocean, the movements of protected species, and the spatial patterns of distribution of potential threats. Nevertheless, there are major challenges to implementing these geospatial approaches in the open ocean. This Theme Section seeks to …


Forest Diversity And Disturbance: Changing Influences And The Future Of Virginia’S Forests, Christine J. Small, James L. Chamberlain Oct 2015

Forest Diversity And Disturbance: Changing Influences And The Future Of Virginia’S Forests, Christine J. Small, James L. Chamberlain

Virginia Journal of Science

The Virginia landscape supports a remarkable diversity of forests, from maritime dune woodlands, swamp forests, and pine savannas of the Atlantic Coastal Plain, to post-agricultural pine-hardwood forests of the Piedmont, to mixed oak, mesophytic, northern hardwood, and high elevation spruce-fir forests across three mountain provinces in western parts of the state. Virginia’s forests also have been profoundly shaped by disturbance. Chestnut blight, hemlock woolly adelgid, emerald ash borer, and other pests have caused declines or functional extirpation of foundation species. Invasive plants like multiflora rose, Oriental bittersweet, and Japanese stiltgrass threaten both disturbed and intact forests. Oaks and other fire-dependent …


Acclimation, Adaptation, Traits And Trade-Offs In Plankton Functional Type Models: Reconciling Terminology For Biology And Modelling, Kevin J. Flynn, Michael St. John, John A. Raven, David O. F. Skibinski, J. Icarus Allen, Aditee Mitra, Eileen E. Hofmann Jan 2015

Acclimation, Adaptation, Traits And Trade-Offs In Plankton Functional Type Models: Reconciling Terminology For Biology And Modelling, Kevin J. Flynn, Michael St. John, John A. Raven, David O. F. Skibinski, J. Icarus Allen, Aditee Mitra, Eileen E. Hofmann

CCPO Publications

We propose definitions in terminology to enhance ongoing collaborations between biologists and modellers on plankton ecology. Organism "functional type" should refer to commonality in ecology not biogeochemistry; the latter is largely an emergent property of the former, while alignment with ecology is also consistent with usage in terrestrial science. Adaptation should be confined, as in genetics, to consideration of species inter-generational change; most so-called "adaptive" plankton models are thus acclimative, modifying vital rates in response to stimuli. Trait trade-off approaches should ideally only be considered for describing intra-generational interactions; in applications between generations, and certainly between unrelated species, such concepts …


Creating A Foundation For The Causal Relationship Between Libraries And Learning: A Proposed Application Of Nursing And Public Health Research Methods, Marcia A. Mardis, Sylvia K. Norton, Gail K. Dickinson, Shana Pribesh, Allison Cline, Sue Kimmel, Jody Howard Jan 2015

Creating A Foundation For The Causal Relationship Between Libraries And Learning: A Proposed Application Of Nursing And Public Health Research Methods, Marcia A. Mardis, Sylvia K. Norton, Gail K. Dickinson, Shana Pribesh, Allison Cline, Sue Kimmel, Jody Howard

Teaching & Learning Faculty Publications

Thomas Cook, a renowned causal research expert and professor of sociology, psychology, education, and social policy at Northwestern University (USA), called for school library researchers to parallel causality determination efforts in health-related fields. In this paper, we respond to Dr. Cook’s challenge with a proposed research design centered on Mixed Research Synthesis (MRS) as part of process validated by the U.S. Department of Education and National Science Foundation’s Common Guidelines for Education Research and Development. MRS studies, often used in nursing and public health research to develop causal theories, enable researchers to develop evidence summaries; identify and adjudicate rival and …


Spatio-Temporal Patterns Of Water Table And Vegetation Status Of A Deserted Area, Limin Duan, Tingxi Liu, Xixi Wang, Yanyun Luo Jan 2015

Spatio-Temporal Patterns Of Water Table And Vegetation Status Of A Deserted Area, Limin Duan, Tingxi Liu, Xixi Wang, Yanyun Luo

Civil & Environmental Engineering Faculty Publications

Understanding groundwater-vegetation interactions is crucial for sustaining fragile environments of desert areas such as the Horqin Sandy Land (HSL) in northern China. This study examined spatio-temporal variations in the water table and the associated vegetation status of a 9.71 km2 area that contains meadowland, sandy dunes, and intermediate transitional zones. The depth of the water table and hydrometeorologic parameters were monitored and Landsat Thematic Mapper (TM) and Moderate Resolution Imaging Spectroradiometer (MODIS) data were utilized to assess the vegetation cover. Spatio-temporal variations over the six-year study period were examined and descriptive groundwater-vegetation associations developed by overlaying a water table …


Interaction Between Climatic, Environmental, And Demographic Factors On Cholera Outbreaks In Kenya, James D. Stoltzfus, Jane Y. Carter, Muge Akpinar-Elci, Martin Matu, Victoria Kimotho, Mark J. Giganti, Daniel Langat, Omur C. Elsi Jan 2014

Interaction Between Climatic, Environmental, And Demographic Factors On Cholera Outbreaks In Kenya, James D. Stoltzfus, Jane Y. Carter, Muge Akpinar-Elci, Martin Matu, Victoria Kimotho, Mark J. Giganti, Daniel Langat, Omur C. Elsi

Community & Environmental Health Faculty Publications

Background:

Cholera remains an important public health concern in developing countries including Kenya where 11,769 cases and 274 deaths were reported in 2009 according to the World Health Organization (WHO). This ecological study investigates the impact of various climatic, environmental, and demographic variables on the spatial distribution of cholera cases in Kenya.

Methods:

District-level data was gathered from Kenya’s Division of Disease Surveillance and Response, the Meteorological Department, and the National Bureau of Statistics. The data included the entire population of Kenya from 1999 to 2009.

Results:

Multivariate analyses showed that districts had an increased risk of cholera outbreaks when …


Exposure To Endocrine Disrupting Chemicals And Male Reproductive Health, Hueiwang Anna Jeng Jan 2014

Exposure To Endocrine Disrupting Chemicals And Male Reproductive Health, Hueiwang Anna Jeng

Community & Environmental Health Faculty Publications

Endocrine disrupting chemicals (EDCs) can interfere with normal hormonal balance and may exert adverse consequences on humans. The male reproductive system may be susceptible to the effects of such environmental toxicants. This review discusses the recent progress in scientific data mainly from epidemiology studies on the associations between EDCs and male reproductive health and our understanding of possible mechanisms associated with the effects of EDCs on male reproductive health. Finally, the review provides recommendations on future research to enhance our understanding of EDCs and male reproductive health. The review highlights the need for (1) well-defined longitudinal epidemiology studies, with appropriately …


Evolution Of The Freshwater Sardinella, Sardinella Tawilis (Clupeiformes: Clupeidae), In Taal Lake, Philippines And Identification Of Iits Marine Sister-Species, Sardinella Hualiensis, Demian Willette, Kent E. Carpenter, Mudjekeewis Santos Jan 2014

Evolution Of The Freshwater Sardinella, Sardinella Tawilis (Clupeiformes: Clupeidae), In Taal Lake, Philippines And Identification Of Iits Marine Sister-Species, Sardinella Hualiensis, Demian Willette, Kent E. Carpenter, Mudjekeewis Santos

Biological Sciences Faculty Publications

We identify the sister species of the world's only freshwater sardinella, Sardinella tawilis (Herre, 1927) of Taal Lake, Philippines as the morphologically-similar marine Taiwanese sardinella Sardinella hualiensis (Chu and Tsai, 1958). Evidence of incomplete lineage sorting and a species tree derived from three mitochondrial genes and one nuclear gene indicate that S. tawilis diverged from S. hualiensis in the late Pleistocene. Neutrality tests, mismatch distribution analysis, sequence diversity indices, and species tree analysis indicate populations of both species have long been stable and that the divergence between these two lineages occurred prior to the putative 18th century formation of Taal …


Systematic Ichthyofaunal Surveys In Urban And Non-Urban Watersheds, Eugene G. Maurakis, David V. Grimes, Amanda Schutt, Suzy Short Jan 2013

Systematic Ichthyofaunal Surveys In Urban And Non-Urban Watersheds, Eugene G. Maurakis, David V. Grimes, Amanda Schutt, Suzy Short

Virginia Journal of Science

Objectives were to model fish species richness relative to natural and anthropogenic variables in Quantico Creek, a forested undisturbed stream environment, and Cameron Run, a highly disturbed urban stream environment in the lower Piedmont-Fall Line region of the Potomac River watershed. Species richness in all stream orders (e.g. avg. range=2.5-9.65 in 1st-3rd orders) of Quantico Creek were significantly higher than those (e.g. avg. range=2.1- 7.6 in 1st -4th orders) of Cameron Run. Fish species richness in Quantico Creek watershed can be modeled by eight factors: season, stream order, elevation, river km, stream width and depth, watershed size, and percent of …


Chemical Defense Of An Asian Snake Reflects Local Availability Of Toxic Prey And Hatchling Diet, D. A. Hutchinson, A. H. Savitzky, G. M. Burghardt, C. Nguyen, J. Meinwald, F. C. Schroeder, A. Mori Jan 2013

Chemical Defense Of An Asian Snake Reflects Local Availability Of Toxic Prey And Hatchling Diet, D. A. Hutchinson, A. H. Savitzky, G. M. Burghardt, C. Nguyen, J. Meinwald, F. C. Schroeder, A. Mori

Biological Sciences Faculty Publications

Species that sequester toxins from prey for their own defense against predators may exhibit population-level variation in their chemical arsenal that reflects the availability of chemically defended prey in their habitat. Rhabdophis tigrinus is an Asian snake that possesses defensive glands in the skin of its neck (nuchal glands'), which typically contain toxic bufadienolide steroids that the snakes sequester from consumed toads. In this study, we compared the chemistry of the nuchal gland fluid of R.tigrinus from toad-rich and toad-free islands in Japan and determined the effect of diet on the nuchal gland constituents. Our findings demonstrate that captive-hatched juveniles …


Phytoplankton In Virginia Lakes And Reservoirs, Harold G. Marshall Jan 2013

Phytoplankton In Virginia Lakes And Reservoirs, Harold G. Marshall

Virginia Journal of Science

This study involves a phytoplankton summer/autumn survey in 46 Virginia lakes and reservoirs during 2010-2012. A total of 307 taxa were identified which included several filamentous and colonial cyanabacteria in bloom concentrations. With the exception of one natural lake, the other sites sampled represent impoundments created decades ago, with the majority presently classified as meso- or eutrophic. Among the cyanobacteria were 6 known toxin producers (Anabaena circinalis, Anabaena spiroides, Aphanizomenon flos-aquae, Cylindrospermopsis raciborskii, Limnothrix redekei, and Microcystis aeruginosa). The study characterizes phytoplankton populations in these aging freshwater habitats taken from a large number …


Effect Of Laser Ablation Depth In Otolith Life History Scans, Renée R. Hoover, Cynthia M. Jones Jan 2013

Effect Of Laser Ablation Depth In Otolith Life History Scans, Renée R. Hoover, Cynthia M. Jones

OES Faculty Publications

Life history scans of fish otoliths are bringing new insight into the structure, connectivity, and movement of fish populations. Data obtained from such scans, however, possess in-herent limitations that have not yet been fully addressed or understood. For example, several investigators have noted delays in otolith elemental uptake that do not appear to reflect habitat exposure. We hypothesized that the 3-dimensional structure of otoliths may produce sampling artifacts in the results obtained from laser ablation scans. To test this hypothesis, we sampled sagittal otoliths from juvenile Atlantic croaker Micropogonias undulatus with laser ablation inductively coupled plasma mass spectrometry to obtain …


Phytoplankton In Virginia Lakes And Reservoirs, Harold G. Marshall Jan 2013

Phytoplankton In Virginia Lakes And Reservoirs, Harold G. Marshall

Biological Sciences Faculty Publications

This study involves a phytoplankton summer/autumn survey in 46 Virginia lakes and reservoirs during 2010-2012. A total of 307 taxa were identified which included several filamentous and colonial cyanabacteria in bloom concentrations. With the exception of one natural lake, the other sites sampled represent impoundments created decades ago, with the majority presently classified as meso- or eutrophic. Among the cyanobacteria were 6 known toxin producers (Anabaena circinalis, Anabaena spiroides, Aphanizomenon flos-aquae, Cylindrospermopsis raciborskii, Limnothrix redekei, and Microcystis aeruginosa). The study characterizes phytoplankton populations in these aging freshwater habitats taken from a large number …