| Accessibility Statement

Odum School Small Grant Awards 2013

Rock pigeon

The purpose of Andrea Ayala’s research was to investigate the effects of helminth (worm) co-infection with naturally circulating Pigeon Paramyxovirus -1, an RNA virus, in a model rock pigeon system. Pigeons were captured and sampled in downtown Atlanta between June and October of 2012. Specifically, the hypothesis Andrea was testing was whether chronic parasitism influences susceptibility and infectiousness (transmission potential) of Pigeon Paramyxovirus-1 in wild rock pigeons. Interestingly enough, while she did not find naturally occurring (or wild type) Pigeon Paramyxovirus-1, Andrea did find evidence (through molecular sequencing) of vaccine spillover for a closely related strain called Newcastle disease virus. Since this vaccine is used in commercial poultry, this suggests that not only are Atlanta pigeons interacting with poultry within their home range of 10 km, but also that the vaccine used in chickens has escaped into the environment.


Cattle in Peru.Daniel Becker’s small grant has allowed him to pursue exploratory field studies of vampire bat rabies in Peru. The goals of Daniel’s research are to determine how the accidental provisioning of vampire bats through livestock intensification influences the movement and immunity of these animals, both of which relate to patterns of rabies transmission and persistence. He is also interested in how this provisioning affects human contact with bats and risk of rabies exposure. Field studies funded by the small grant allowed Daniel to begin this research through visiting sites and establishing connections with local communities and organizations in an area of frequent human rabies outbreaks.


Research equipment.Sarah Bowden’s award funded her research that looks at the effects of density and competition on population dynamics and life history traits of medically important larval mosquito species. The goal of her experiment is to establish determinants of community diversity in adult disease vectors. This is important because different mosquito species have different abilities to transmit certain pathogens, so their relative abundance in the vector community has the potential to affect pathogen transmission dynamics. Data from this experiment will be used to parameterize a dynamical systems model that will simulate the multi-generational effects of larval interactions on the resulting adult vector community composition.


Phillip Bumpers working in a headwater stream.Phillip Bumpers received an Odum small grant to fund sample analyses. His research focuses on the effects that nutrient enrichment (think nitrogen and phosphorus from livestock, agriculture, urbanization, etc.) has on headwater stream foodwebs. Specifically, he is looking at how increased nutrients in streams affect the prey availability of larval salamanders—the top predator in many Southern Appalachian headwaters—and alters the flow of nutrients and energy through headwater stream foodwebs. It is thought that increased nutrients may change the community of salamander prey, thus potentially altering the flow of nutrients and energy to salamanders. Studying effects on top predators can tell us something about how the whole system is responding to nutrient enrichment.




Tad Dallas is exploring a paradigm in disease ecology which posits that increased host diversity will reduce infection prevalence in a susceptible host population (the so-called "dilution effect"). However, laboratory tests of this hypothesis are limited. With his small grant Tad has designed and implemented an experiment which uses small crustacean zooplankton parasitized by a fungal pathogen to examine the presence of a dilution effect along a gradient competition.


Rebeca de Jesús-Crespo.Rebeca G. de Jesús-Crespo’s project studies the effects of coffee agriculture on streams. Rebeca received a small grant to purchase high resolution aerial photography from coffee farms in Costa Rica, where her study is located. She needed the images to describe in detail the coffee landscapes in terms of the percentage of coffee farm planted under shade trees and the density of dirt roads across coffee-dominated watersheds. Rebeca will then determine how these variables relate to stream parameters related to water quality and biological health. Her goal is to create a Stream Friendly Coffee certification framework by determining how much tree cover per area would be optimal to protect coffee watersheds. These images have been crucial in advancing Rebeca’s dissertation research.


Carissa Ganong.Carissa Ganong’s doctoral research examines how climate change impacts tropical streams, with a focus on climate-driven seasonal acidification in rainforest streams. These natural pH decreases, currently studied in detail in Costa Rica, have the potential to occur widely across the tropics and may also become more pronounced as dry seasons intensify in the Neotropics, with possibly severe consequences for aquatic ecosystems. Carissa is working to determine the biogeochemical mechanism(s) behind these pH drops (possible mechanisms include metal redox, CO2 inputs, and/or fluxes of major ions), and part of her dissertation research consists of a comparison of water chemistry in dry vs. wet season at 50 stream and groundwater-seep sites in Costa Rican rainforest. The Odum small grant provided Carissa with the funding to conduct ion analyses on those water samples to determine (1) whether concentrations of major ions (sulfate, nitrate, etc.) in the water samples differ between wet and dry seasons, and (2) whether ion concentrations are related to stream pH. Once the resulting data are fully analyzed, they will be invaluable in providing support (or lack of support) for the ion-flux mechanism of stream acidification.


Diagram showing hypothetical evolutionary history of heavy metal tolerance for certain sunflower species.Eric Goolsby used the small grant to help fund a greenhouse experiment involving heavy metal hyper-accumulation (the process of taking up extremely large amounts of a substance into plant leaves) in ten closely related annual sunflowers species. This was a phylogenetic investigation into the evolutionary origins of metal hyperaccumulation. The greenhouse phase of the experiment is now complete, and Eric is currently in the process of analyzing collected plant tissues. However, initial results suggest an interesting evolutionary trajectory for this trait. The corresponding image depicts a very preliminary figure representing an ancestral state reconstruction (hypothetical evolutionary history) of heavy metal tolerance for the species in the experiment under different forms of soil heavy metal exposure.


Kristy Segal.Kristy Segal is a doctoral candidate in the Odum School of Ecology, working with Dr. Ron Carroll in the Odum School and Dr. Sonia Hernandez in the Warnell School of Forestry and Natural Resources. Her dissertation work focuses on amphibians in Costa Rica and how their health is affected by pesticide usage. Specifically, she is using a weight-of-evidence approach to assess the health status of Bufo marinus in agricultural habitats along a pesticide use gradient. In addition, she is collecting data on the entire amphibian community in these habitats. Her research involves aspects of ecology, ecoimmunology, ecotoxicology, and wildlife health to answer questions with real conservation implications. She hopes that the results of her research will be used to improve agricultural practices in Central America to better protect sensitive amphibian species.


Marcus Zokan's experimental site.A frequently observed pattern in wetland ecology is the increase in species richness of aquatic invertebrates as the length of wetland inundation increases, and a decrease when wetlands become permanent. One hypothesis for this pattern (the predation-permanence hypothesis) is that the stress of wetland drying on populations is lessened as length of inundation increases, but that predation pressure increases at the same time, leading to the observed pattern. Marcus Zokan’s research investigates the relationship between length of inundation, predation pressure, and species diversity through a mesocosm experiment using microcrustacean zooplankton. Marcus’ experiment consists of 36 mesocosms seeded with organisms from several natural wetlands and subjected to three inundation regimes and having salamander larvae (the dominant predator in temporary wetlands) present or absent. Through this experiment he hopes to gain a better understanding of the factors influencing diversity in wetlands and how change in wetland inundation regimes impact their biota.





UGA Alumni Association

Make a Georgia Fund Gift

Update Your Address

Sign up for EcoVoice Update

Office of Development and Alumni Relations

Development and Alumni Relations Coordinator
Allison Walters
(706) 542-6007