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The Paradoxical Giant Hummingbird: Comparison Of Andean And Coastal Subspecies With Respect To Blood, Migration, And Genes, Jessie L. Williamson 2018 University of New Mexico

The Paradoxical Giant Hummingbird: Comparison Of Andean And Coastal Subspecies With Respect To Blood, Migration, And Genes, Jessie L. Williamson

Shared Knowledge Conference

The Giant Hummingbird (Patagona gigas) is twice as large as the next largest hummingbird species and has long been considered paradoxical with respect to flight biomechanics. It is also an extreme outlier in other respects. For example, it is the only hummingbird species that breeds above 4,000 m elevation and also along the beaches of the Pacific Ocean. The high Andean populations of Giant Hummingbird (P. g. peruviana) that we have studied previously have a beta-hemoglobin genotype (serine at beta-hemoglobin A positions 13 and 83) that is characterized by high O2-affinity and is only shared with four unrelated hummingbird ...


42 - A Comparison Of Two Automated Bat-Call Classifying Software Programs., Sara Robertson, Michael Bender 2018 University of North Georiga

42 - A Comparison Of Two Automated Bat-Call Classifying Software Programs., Sara Robertson, Michael Bender

Georgia Undergraduate Research Conference (GURC)

Bats are an integral part of many ecosystems and provide numerous valuable services such as pollination, seed dispersal and, in our region, insect control. Sampling the bat community to assess ecosystem health and document bat species of conservation interest is typically accomplished by capturing individuals in combination with collecting acoustic data. Acoustic sampling has the advantages of being effective in many varied habitat types, potentially less biased than capture data, and non-invasive to the bats. Many surveys are now entirely acoustic as the technology and ability to assign species identification to each has advanced substantially during the last few decades ...


Localized Environmental Variables Affecting Southern Appalachian Salamander Populations, Jasmine Williamson 2018 University of North Georgia

Localized Environmental Variables Affecting Southern Appalachian Salamander Populations, Jasmine Williamson

Georgia Undergraduate Research Conference (GURC)

Amphibians are an essential group of organisms for understanding ecological dynamics due to their acute sensitivity to temperature, precipitation, and other environmental variables. Northeast Georgia in particular is ideal for studying amphibians due to the elevated diversity of plethodontid salamanders in the southern Appalachian Mountains. The purpose of this study is to investigate the effects of biotic and abiotic factors on salamander diversity and ecology. This study utilized drift fence arrays with pitfall traps to survey local salamander populations daily for a 90-day period in two forest sites (Sites A and B) in Lumpkin County, Georgia. A third site (Site ...


Hidden Cost Of Disease In A Free-Ranging Ungulate: Brucellosis Reduces Mid-Winter Pregnancy In Elk, Gavin C. Cotterill, Paul C. Cross, Arthur D. Middleton, Jared D. Rogerson, Brandon M. Scurlock, Johan T. du Toit 2018 Utah State University

Hidden Cost Of Disease In A Free-Ranging Ungulate: Brucellosis Reduces Mid-Winter Pregnancy In Elk, Gavin C. Cotterill, Paul C. Cross, Arthur D. Middleton, Jared D. Rogerson, Brandon M. Scurlock, Johan T. Du Toit

Wildland Resources Faculty Publications

Demonstrating disease impacts on the vital rates of free‐ranging mammalian hosts typically requires intensive, long‐term study. Evidence for chronic pathogens affecting reproduction but not survival is rare, but has the potential for wide‐ranging effects. Accurately quantifying disease‐associated reductions in fecundity is important for advancing theory, generating accurate predictive models, and achieving effective management. We investigated the impacts of brucellosis (Brucella abortus) on elk (Cervus canadensis) productivity using serological data from over 6,000 captures since 1990 in the Greater Yellowstone Ecosystem, USA. Over 1,000 of these records included known age and pregnancy status. Using Bayesian ...


An Evaluation Of Sciaenid Growth In The Gulf Of Mexico, Shane Flinn 2018 Louisiana State University

An Evaluation Of Sciaenid Growth In The Gulf Of Mexico, Shane Flinn

LSU Master's Theses

Growth models estimate life history parameters that are used in the management of fisheries stocks. The most commonly used growth model in fisheries is the von Bertalanffy growth model (VBGM), yet it has been shown to provide a poor fit for length-at-age data of some species and other models exist. I reviewed 196 peer-reviewed age and growth studies and 50 NOAA stock assessments to examine temporal trends in the use of growth models and model selection in fisheries. I found that the use of multi-model frameworks has increased since the year 2000 and information theoretic approaches are replacing goodness-of-fit and ...


Modeling The Transmission Of Wolbachia In Mosquitoes For Controlling Mosquito-Borne Diseases, Zhuolin Qu 2018 Illinois State University

Modeling The Transmission Of Wolbachia In Mosquitoes For Controlling Mosquito-Borne Diseases, Zhuolin Qu

Annual Symposium on Biomathematics and Ecology: Education and Research

No abstract provided.


Dynamics Of A Stoichiometric Producer-Grazer System With Seasonal Effects On Light Level, Lale Asik 2018 Illinois State University

Dynamics Of A Stoichiometric Producer-Grazer System With Seasonal Effects On Light Level, Lale Asik

Annual Symposium on Biomathematics and Ecology: Education and Research

No abstract provided.


Stochastic Difference Model For Evolutional Dynamics Of Large Antigen Repertoires In African Trypanosomes, Fan Yu 2018 Illinois State University

Stochastic Difference Model For Evolutional Dynamics Of Large Antigen Repertoires In African Trypanosomes, Fan Yu

Annual Symposium on Biomathematics and Ecology: Education and Research

No abstract provided.


Delayed Trait Development And The Convergent Evolution Of Shell Kinesis In Turtles, Gerardo A. Cordero, Kevin Quinteros, Fredric J. Janzen 2018 Iowa State University

Delayed Trait Development And The Convergent Evolution Of Shell Kinesis In Turtles, Gerardo A. Cordero, Kevin Quinteros, Fredric J. Janzen

Ecology, Evolution and Organismal Biology Publications

Developmental processes are foundational to clarifying the causes of convergent evolution. Here, we show how a key convergently evolving trait is slowly “acquired” in growing turtles. Adaptive morphological change tends to originate late in turtle ontogeny, owing to design constraints imposed by the shell. We investigated this trend by examining derived patterns of shell formation associated with the multiple (≥ 8) origins of shell closure (kinesis) in smallbodied turtles. Using box turtles as a model, we demonstrate that the flexible hinge joint required for shell kinesis differentiates gradually and via extensive repatterning of shell tissue. Disproportionate changes in shell shape and ...


Reproductive Timing Of The Scarlet Shiner (Lythrurus Fasciolaris) In Northern Alabama, Bruce Stallsmith, Toacca Taylor, Chelsie Smith 2018 University of Alabama - Huntsville

Reproductive Timing Of The Scarlet Shiner (Lythrurus Fasciolaris) In Northern Alabama, Bruce Stallsmith, Toacca Taylor, Chelsie Smith

Southeastern Fishes Council Proceedings

The Scarlet Shiner (Lythrurus fasciolaris) is a cyprinid species widely distributed in parts of the Ohio, Cumberland and Tennessee river drainages of the United States. The objective of this study was to determine the Scarlet Shiner’s reproductive schedule. Maturation of ovaries and oocytes was determined through the categorization of developmental stages from early maturing to ripe, along with the calculation of monthly gonadosomatic index (GSI) measurements over two reproductive seasons in 2012 and 2015. In both years reproductive competence began in April. Average monthly GSI for females peaked in May, followed by a slow decline through August. Average clutch ...


The Contribution Of Local And Transport Processes To Phytoplankton Biomass Variability Over Different Timescales In The Upper James River, Virginia, Qubin Qin, Jian Shen 2018 Virginia Institute of Marine Science

The Contribution Of Local And Transport Processes To Phytoplankton Biomass Variability Over Different Timescales In The Upper James River, Virginia, Qubin Qin, Jian Shen

Articles

Although both local processes (photosynthesis, respiration, grazing, and settling), and transport processes (advective transport and diffusive transport) significantly affect local phytoplankton dynamics, it is difficult to separate their contributions and to investigate the relative importance of each process to the local variability of phytoplankton biomass over different timescales. A method of using the transport rate is introduced to quantify the contribution of transport processes. By combining the time-varying transport rate and high-frequency observed chlorophyll a data, we can explicitly examine the impact of local and transport processes on phytoplankton biomass over a range of timescales from hourly to annually. For ...


Improving Our Understanding Of Demographic Monitoring: Avian Breeding Productivity In A Tropical Dry Forest, M. Edye Kornegay, Amber N. M. Wiewel, Jaime A. Collazo, James F. Saracco, Stephen J. Dinsmore 2018 North Carolina State University

Improving Our Understanding Of Demographic Monitoring: Avian Breeding Productivity In A Tropical Dry Forest, M. Edye Kornegay, Amber N. M. Wiewel, Jaime A. Collazo, James F. Saracco, Stephen J. Dinsmore

Natural Resource Ecology and Management Publications

The ratio of juvenile to adult birds in mist‐net samples is used to monitor avian productivity, but whether it is a “true” estimate of per capita productivity or an index proportional to productivity depends on whether capture probability is not age‐dependent (true estimate) or age difference in capture probability is consistent among years (index). Better understanding of the processes affecting age‐ and year‐specific capture probabilities is needed to advance the application of constant‐effort mist‐netting for monitoring and conservation, particularly in many tropical settings where capture rates are often low. We ranked members of the avian ...


Japanese Beetles’ Feeding On Milkweed Flowers May Compromise Efforts To Restore Monarch Butterfly Habitat, Adam M. Baker, Daniel A. Potter 2018 University of Kentucky

Japanese Beetles’ Feeding On Milkweed Flowers May Compromise Efforts To Restore Monarch Butterfly Habitat, Adam M. Baker, Daniel A. Potter

Entomology Faculty Publications

The eastern North American migratory population of monarch butterflies (Danaus plexippus) is in serious decline. Habitat restoration, including adding millions of host plants to compensate for loss of milkweed in US cropland, is a key part of the international conservation strategy to return this iconic butterfly to sustainable status. We report here that Popillia japonica, a polyphagous, invasive beetle, aggregates and feeds on flowers of Asclepias syriaca, the monarch’s most important larval food plant, reducing fruiting and seed set by >90% and extensively damaging milkweed umbels in the field. The beetle’s ongoing incursion into the monarch’s key ...


Yardwork: A Biography Of An Urban Place By Daniel Coleman, Vivian M. Hansen 2018 University of Calgary

Yardwork: A Biography Of An Urban Place By Daniel Coleman, Vivian M. Hansen

The Goose

Review of Daniel Coleman's Yardwork: A Biography of an Urban Place.


Analysis Of Temperature And Salinity Effects On Growth And Mortality Of Oysters (Crassostrea Virginica) In Louisiana, Troy Sehlinger 2018 University of New Orleans

Analysis Of Temperature And Salinity Effects On Growth And Mortality Of Oysters (Crassostrea Virginica) In Louisiana, Troy Sehlinger

University of New Orleans Theses and Dissertations

Salinity (S) and temperature (T) control every facet of the eastern oyster (Crassostrea virginica) life cycle, principally reproduction, development, growth, and mortality. Previous studies conducted in in the Breton Sound (BR) and Barataria (BA) estuaries have reported differences in growth and mortality rates between the basins. In the present study, environmental conditions were synchronized to compare growth and mortality rates between basins at similar combinations of T and S. Results indicate that when T and S are the same (synchronized), seasonal oyster growth and mortality rates differ between BR and BA. Seasonal analyses revealed that as salinities increased in both ...


Genetic Diversity In An Invasive Clonal Plant? A Historical And Contemporary Perspective, Elliot D. Weidow 2018 University of New Orleans

Genetic Diversity In An Invasive Clonal Plant? A Historical And Contemporary Perspective, Elliot D. Weidow

University of New Orleans Theses and Dissertations

Introduced populations of Eichhornia crassipes (Pontederiaceae) possess extremely low levels of genetic diversity due to severe bottleneck events and clonal reproduction. While populations elsewhere have been well studied, North American populations of E. crassipes remain understudied. We used Amplified Fragment Length Polymorphism markers to assess genetic diversity and population structure in North American E. crassipes populations. Patterns of diversity over the past fifty years were analyzed using herbarium specimens. Furthermore, we sampled populations across the Gulf Coast of the United States throughout a year to determine contemporary genetic diversity and assess potential seasonal effects. Genetic diversity was found to be ...


The Population Ecology And Behavior Of The Cave Salamander, Eurycea Lucifuga (Rafinesque, 1822)., Joseph Gavin Bradley 2018 University of Louisville

The Population Ecology And Behavior Of The Cave Salamander, Eurycea Lucifuga (Rafinesque, 1822)., Joseph Gavin Bradley

Electronic Theses and Dissertations

The Cave Salamander, Eurycea lucifuga (Rafinesque, 1822), is a little-known species, yet a common inhabitant of caves in the eastern United States. Salamanders are often important components of ecological communities and ecosystems, influencing critical processes such as nutrient cycling and community composition through their predation on invertebrates. Cave-dwelling salamanders such as E. lucifuga may thus appreciably influence the relatively simple ecosystems and communities of caves. Any such influence may be particularly important because these habitats and the organisms that reside in them are often of conservation concern. I used non-invasive methods to study the demographics, movements, and habitat selection of ...


Grapevine Vein Clearing Virus: Epidemiological Patterns And Construction Of A Clone, Cory Von Keith 2018 Missouri State University - Springfield

Grapevine Vein Clearing Virus: Epidemiological Patterns And Construction Of A Clone, Cory Von Keith

MSU Graduate Theses

Grapevine vein clearing virus (GVCV) is a recently discovered virus belonging to the Badnavirus genus. Characteristic to its name, the virus is associated with a disease where symptoms manifest as pronounced vein-clearing, resulting in severe berry deformation and vine decline in susceptible grape varieties. Sustainable production of wine is dependent on healthy plants. The associated disease is mainly found in Midwest vineyards. Attempts were made in this thesis to provide evidence of causality of the virus to the associated disease and to infer the historical path and migration pattern of GVCV. Conclusions and discussions will provide grape producers with the ...


Population Modeling For The Reintroduction Of Mexican Gray Wolves As Predators To Decrease The Feral Hog Population In The Southern United States., John H. Kauphusman III 2018 Minnesota State University, Mankato

Population Modeling For The Reintroduction Of Mexican Gray Wolves As Predators To Decrease The Feral Hog Population In The Southern United States., John H. Kauphusman Iii

Journal of Undergraduate Research at Minnesota State University, Mankato

Invasive species are a problem in the United States. As their populations continue to increase in size they disrupt ecological systems. One of the most notorious invasive species is the feral hog. In Texas, the hog populations cause ecological and agricultural damage that costs the state $52 million annually. The reason for the large continuously growing population is that the feral hogs, unlike its relatives in Europe, have no natural predators and hunters cannot suppress the population growth. In Europe, the gray wolf is a predator to the European wild boar. However, wolves in the U.S. have been extirpated ...


Simulation Code For Intraspecific Variability May Not Compensate For Increasing Climatic Volatility, George P. Malanson 2018 University of Iowa

Simulation Code For Intraspecific Variability May Not Compensate For Increasing Climatic Volatility, George P. Malanson

Research Data

The role of intraspecific variability is being examined to improve predictions of responses to climate change or invasions and in research on diversity. Simultaneously, the probability and implications of increased high-frequency climate variability have been raised. An agent based model simulated two species on an environmental gradient representing an alpine treeline; a trend in its volatility was added. The species have different levels of variability, and each individual has further unique heterogeneity. Environmental volatility and individual heterogeneity were based on tree ring data from Pinus albicaulis. Simulations show that increasing volatility leads to population declines, including extinctions, and to sharper ...


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