Terrestrial and Aquatic Ecology Commons^™

Predation In A Natural Community Of Marine Mollusks: Using Morphology To Determine Predator-Prey Ecology, Danielle N. Araiza, Erica Valdez

DePaul Discoveries

Predatory gastropod mollusks in the family Naticidae feed on bivalve mollusks and leave distinctive markings in the form of countersunk circular boreholes on the shells. These boreholes possess both an inner borehole diameter (IBD) and an outer borehole diameter (OBD) which are proportional to the size of the predator. It has been proposed that the ratio of IBD to OBD can be used to identify predator species. Variation in the ratio of the IBD to OBD was examined in two prey species (Dwarf surf clam, Incongruous ark clam) collected from Otter Island beach in South Carolina to determine if clams …

A Comparison Of Plot-Based Satellite And Earth System Model Estimates Of Tropical Forest Net Primary Production, Cory C. Cleveland, Philip Taylor, K. Dana Chadwick, Kyla Dahlin, Christopher E. Doughty, Yadvinder Malhi, W. Kolby Smith, Benjamin W. Sullivan, William R. Wider, Alan R. Townsend

Ecosystem and Conservation Sciences Faculty Publications

Net primary production (NPP) by plants represents the largest annual flux of carbon dioxide (CO₂) from the atmosphere to the terrestrial biosphere, playing a critical role in the global carbon (C) cycle and the Earth’s climate. Rates of NPP in tropical forests are thought to be among the highest on Earth, but debates about the magnitude, patterns, and controls of NPP in the tropics highlight uncertainty in our understanding of how tropical forests may respond to environmental change. Here, we compared tropical NPP estimates generated using three common approaches: (1) field-based methods scaled from plot-level measurements of plant …

The Response Of Zooplankton Communities In Montane Lakes Of Different Fish Stocking Histories To Atmospheric Nitrogen Deposition Simulations, Jeffrey Thomas Brittain

Dissertations and Theses

Freshwater ecosystems are subject to a wide variety of stressors, which can have complex interactions and result in ecological surprises. Non-native fish introductions have drastically reduced the number of naturally fishless lakes and have resulted in cascading food web repercussions in aquatic and terrestrial habitats. Additional anthropogenic influences that result from increases in global airborne emissions also threaten wildlife habitat. Atmospheric nitrogen deposition has been recognized as an anthropogenic contributor to acidification and eutrophication of wilderness ecosystems. Planktonic communities have shown declines in response to predation and shifts in composition as a result of nutrient inputs and acidification, both of …

Local Patterns In Host-Selection By Anemone Symbionts In Bocas Del Toro, Panama, Samantha Mercer

Undergraduate Honors Theses

The associations made between many symbiotic cleaner shrimps and their host anemone species are influenced by local ecological factors, resulting in regional variations in symbiont-host preferences. These relationships are crucial parts of aquatic ecosystems, and as we face rapid global environmental change, understanding the local patterns of this host specificity will be essential to maintaining healthy marine environments. However, sea anemones, as well as their symbiotic relationships, from the Caribbean coasts of Panama have been poorly studied and are largely under-represented in the current literature. The purpose of this study is to identify the local host-selection patterns, specifically regarding host-size …

Evaluation Of Temperature Anomalies And Ocean Productivity During The 2004 Sumatra-Andaman Earthquake, Cora Byers, Brenna Mcnabb

Student Scholar Symposium Abstracts and Posters

The oceanic productivity of the Indian Ocean and temperature anomalies prior to the Sumatra-Andaman earthquake (MW =9.3) and tsunami (December 26th 2004) were studied. Data was obtained via NASA’s Giovanni program to determine the effect on phytoplankton (primary producers) and temperature changes over the region of the earthquake. Seasonal trends were visible in the concentrations of chlorophyll a, coccolithophores, cyanobacteria, chlorophytes, diatoms and absorption coefficient, in addition to storm trends.

Possible Precursor Events To Earthquakes And The Resulting Effects On Organic Material In The Surrounding Water Bodies, Kiyoko Nakatsui

Student Scholar Symposium Abstracts and Posters

Being located on the “Ring of Fire” Japan experiences many seismic events. Adding to this, it is located at the convergence of four fault lines where seismic activity will be even more frequent and severe. Although small tremors occurring in an area are indicators of an earthquake to come it only gives minutes of warning. Scientists are now trying to see if latent heat and gas release from fault lines can indicate an earthquake to come with hours or even days of warning. MODIS aqua and terra data will be analyzed in order to see if such precursors can be …

Puffs And Tufts: A Comparison Of Trichodesmium Colony Formations And Nutrient Availability Across The North Atlantic Ocean Using Remote Sensing Methods, Marc Rosenfield

Student Scholar Symposium Abstracts and Posters

Trichodesmium, a genus of diazotrophic bacteria, has the capability and the population to produce a large percentage of the total oceanic N2-fixation. Though their population is known to be heavily dependent on two of the ocean’s largest limiting factors, phosphorus and iron concentrations, it is unknown what affect these factors have on the population. In this study two of the largest colony formations of Trichodesmium in the North Atlantic, tufts and puffs, are compared nutrient quality with respect to time and geographical location. Though very little nutrient in situ data was collected from the cruise, remote sensing data collected from …

Effects Of El Niño On Ecological Growth Along Californian And Peruvian Coasts, Alexandra Sidun

Student Scholar Symposium Abstracts and Posters

This study examines the mechanisms of El Niño to further understand the ecological effects it may have along the Californian and Peruvian coasts. El Niño is the warm phase of the El Niño Southern Oscillation (ENSO). While it is a global phenomenon, these two locations were investigated for their nearly equal and opposite conditions during storm months. California, which is in an extreme state of drought, often receives heavy rainfall during El Niño and understanding its potential effects is crucial. El Niño causes upwellings along the CA coast and warm water from the region displaces the normally cool waters along …

Assessing Water Quality In The Gulf Of Mexico Using Remote Sensing Data., Alliyah Thomas

Student Scholar Symposium Abstracts and Posters

Hypoxia, or oxygen depletion, is a process that occurs in conjunction with eutrophication. In hypoxic conditions the dissolved oxygen levels in the water column sink to unlivable conditions for the marine organisms causing them to flee or die. Despite efforts of improvement, the annual summer Gulf of Mexico dead zone continues to be a serious threat to aquatic ecosystems. The 2012 smaller than usual dead zone was a false indicator of future improvement. The 2012 dead zone decrease was connected to the drought and inability of large amounts of runoff to flow into the gulf. Water quality analysis was done …

Effects Of Human Recreational Activity On The Tameness Of Common Loons (Gavia Immer) In Northern Wisconsin, Seth Yund

Student Scholar Symposium Abstracts and Posters

The Common Loon (Gavia immer) is an aquatic diving bird that lives in freshwater habitats in Canada and the northern U.S.. Human activity on a loon’s resident lake may affect its fitness and behavior, yet few studies identify or quantify these effects. We modified existing techniques that measure escape distances in other species to measure tameness as the distance at which individual loons dove in response to human approach by canoe. Tameness was similar between pair members, suggesting that common lake conditions or the behavior of a mate might influence the behavior. Sex, size within sex, and human activity did …

Effects Of Ecologically Realistic Heating Profiles On Feeding In The Intertidal Hermit Crab, Pagurus Sameulis, Paige Davis

Student Scholar Symposium Abstracts and Posters

The intertidal zone is an ideal habitat to investigate effects of global warming because species living in it are very close to their physiological limits. Initial studies of invertebrate physiological responses to heat stress have employed relatively abrupt increases in temperature. My research investigates effects of ecologically more realistic temperature profiles on feeding in the intertidal hermit crab, Pagurus sameulis. Recent work in the Wright lab showed that feeding in this species is inhibited by an abrupt increase in temperature. Because temperature change in the natural environment of Pagurus is much more gradual, I hypothesize that such a gradual temperature …

Biological Degradation Of Acetaldehyde In Southern California Coastal Waters, Mary Senstad, Sovanndara Hok, Ori Barashy, Catherine D. Clark, Warren J. De Bruyn

Student Scholar Symposium Abstracts and Posters

Oxygenated hydrocarbons are ubiquitous in the atmosphere with levels ranging from low ppt (acetaldehyde) to low ppb (methanol). As an OH sink and an atmospheric HOx and ozone source, oxygenated hydrocarbons have a direct impact on the oxidative capacity of the atmosphere. The oceans are one of the largest sources of uncertainty in current atmospheric budget estimates of these species. A better understanding of the processes that produce and destroy these species in seawater would improve our understanding of the role of the oceans in cycling these species into or out of the atmosphere. We have measured the degradation rate …

Comparing Pseudo-Environmental And Horizontal Plus Pseudo-Environmental Transmission Of A Probiotic Janithinobacterium Lividum Between Green Frog Tadpoles, Stephen Simonetti

Senior Honors Projects, 2010-2019

The gram-negative bacteria, Janthinobacterium lividum (J.liv) is able to kill the pathogenic fungus known as Batrachochytrium dendrobatidis (Bd), which is known to be causing massive amphibian decline worldwide. The purpose of this research was to identify the ability of the probiotic bacteria, Janthinobacterium lividum (J.liv), to be horizontally transmitted from individual to individual and/or pseudo-environmentally transmitted from individual to environment and back to individual between Lithobates clamitans (green frog) tadpoles. Based on previous findings I hypothesized that pseudo-environmental and horizontal transmission will occur in tadpoles. This would be important for helping stop the decline of amphibians because it would provide …

Comparative Analysis Of Anti-Bd Bacteria From Six Malagasy Frog Species Of Ranomafana National Park, Kelsey Savage

Senior Honors Projects, 2010-2019

As Malagasy amphibians are facing an impending extinction crisis from the lethal skin fungus Batrachochytrium dendrobatidis (Bd), it has become imperative to proactively mitigate the threat. Bd sporangia develop in the skin of infected amphibians and cause the skin to thicken, leading to ionic imbalance and eventual heart failure. It has been shown that certain bacterial species are able to inhibit Bd growth on amphibians by producing antifungal metabolites. Community-based probiotics are one approach used to combat chytridomycosis by inoculating an environment with Bd-inhibitory bacteria so that many amphibian species are treated at once. With this method, it is important …

Fishing For A Sustainable Future: Aquaponics As A Method Of Food Production, Richard Ramsundar

Student Theses 2015-Present

This thesis compares and explains the advantages aquaponics farming has over modern industrial intensive farming. Through a comparison natural capital usage, conservation, recycling and cost, the thesis advocates for the expansion of aquaponics usage in urban settings. The thesis also explains the history of intensive farming and aquaponics in America, the science of how aquaponics operates, the economic and environmental costs of modern intensive farming versus aquaponics farming, and the social implications of aquaponics. Lastly, I propose a policy that reallocates farm subsidies by modifying the Farm Bill. Then I propose policies that support creating a new standard of farm …

Using Capture-Mark-Recapture Techniques To Estimate Detection Probabilities & Fidelity Of Expression For The Critically Endangered James Spinymussel (Pleurobema Collina)., Alaina C. Esposito

Masters Theses, 2010-2019

The critically endangered James Spinymussel (Pleurobema collina) is a species of freshwater mussel endemic to Virginia’s James and Dan River basins. In the last 20 years, P. collina has experienced a substantial decline in numbers and currently occupies approximately 10% of its original habitat; however, little information is known about this species to assist in conservation. A 230-meter reach of transitional habitat in Swift Run was selected for repeat observations to estimate detection probabilities using a Capture-Mark-Recapture framework. In June 2014, visual scouting began to locate and tag P. collina (including other mussels in the community) with PIT …

Acute Toxicity Of Β-N-Methylamino-L-Alanine (Bmaa) To Fathead Minnow (Pimephales Promelas) And Zebrafish (Danio Rerio), Jiayi Wang

School of Natural Resources: Dissertations, Theses, and Student Research

β-N-methylamino-L-alanine (BMAA) is a neurotoxic amino acid produced by most species of cyanobacteria. Exposure to BMAA has been hypothesized as a cause of ALS and possibly Parkinson’s and Alzheimer’s diseases for several decades. Both in vitro and in vivo experiments revealed that exposure to elevated concentrations of BMAA can damage motor neurons and cause motor dysfunctions. However, the exact mechanism of BMAA-induced neurotoxicity has not been well understood.

Based on the available literature and in spite of its water-soluble and non-protein nature, BMAA appears to be able to bioaccumulate in organisms. The ubiquity of cyanobacteria and the potential for bioaccumulation …

Genetic And Morphological Variation In Ecuadorian Astroblepid Catfishes, Katherine M. Lawry

School of Natural Resources: Dissertations, Theses, and Student Research

The Andean ichthyofauna remains a poorly understood component of Neotropical biodiversity, and stands in stark contrast to the lowland ichthyofauna in terms of number of species and range of distribution. The Climate Variability Hypothesis (CVH) predicts rapid turnover of species along elevational gradients in tropical climates, but it remains unclear whether stream fishes follow this pattern. Astroblepid catfishes represent a distinctive assemblage of species that inhabit high elevation streams throughout the Andes from Panama to Bolivia, and constitute the only native fish family present in the Ecuadorian highland region. In this research, population samples of Astroblepids collected throughout Ecuador’s Napo …

Plant Diversity Affects Performance Of Invasive Thistles In Restored Nebraska Grasslands, Katilyn J. Price

School of Natural Resources: Dissertations, Theses, and Student Research

Invasive plant species threaten native grasslands, affecting nutrient cycling, biodiversity, wildlife habitat, and usable land for production. Consequently, preventing establishment of invasive species is critical before removal becomes difficult and expensive. The purpose of this study was to examine the effects of grassland plant diversity on musk thistle (Carduus nutans) and Canada thistle (Cirsium arvense) establishment and determine which environmental factors (light penetration, soil moisture, plant diversity, and soil nitrogen) account for resistance to invasions. In a field experiment at The Nature Conservancy’s Wood River site (Nebraska), the two invasive thistle species were planted into replicated …

Coupling Soil Oxygen And Greenhouse Gas Dynamics, Karla M. Jarecke

School of Natural Resources: Dissertations, Theses, and Student Research

Dynamic soil hydrology triggers important shifts in soil biogeochemical and physical processes that control greenhouse gas (GHG) emissions. Soil oxygen (O₂), a direct control on biogenic GHG production (e.g. nitrous oxide-N₂O, carbon dioxide-CO₂ and methane-CH₄), may serve as both an important proxy for determining sudden shifts in subsurface biogenic GHG production as well as the physical transport of soil GHG to the atmosphere. Recent technological advancements offer opportunities to link in-situ, near-continuous measurements of soil O₂ concentration to soil biogeochemical processes and soil gas transport. Using high frequency data, this study …