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Title: DOES HABITAT AFFECT CLONAL DEMOGRAPHY? AN EXPERIMENT WITH POLYGONELLA MYRIOPHYLLA IN ROADSIDE AND FLORIDA SCRUB.
Creator: Horn, Kristina, Quintana-Ascencio, Pedro, University of Central Florida
Abstract / Description: Polygonella myriophylla (Polygonaceae) is a clonal shrub listed as endangered and narrowly endemic to pyrogenic scrub ecosystems in central Florida. It is almost restricted to gaps within the matrix of shrubs in the scrub but also occurs along adjacent road-side habitats. I hypothesize that persistent disturbed microhabitats and more dynamic sand accretion in roadsides will increase rooting probabilities compared to more stable scrub habitats, affecting survival, growth and reproduction. In...
Show morePolygonella myriophylla (Polygonaceae) is a clonal shrub listed as endangered and narrowly endemic to pyrogenic scrub ecosystems in central Florida. It is almost restricted to gaps within the matrix of shrubs in the scrub but also occurs along adjacent road-side habitats. I hypothesize that persistent disturbed microhabitats and more dynamic sand accretion in roadsides will increase rooting probabilities compared to more stable scrub habitats, affecting survival, growth and reproduction. In April 2004- March 2006, I compared plant (genet) and basal branch (ramet) performance between experimentally manipulated plants in native scrub and roadside habitats at two locations within the Lake Wales Ridge State Forest in Polk County: LC01 and Old School. We completed a total of 6 evaluations in each site (April, July and November 2004, May and November 2005, and March 2006). Fifteen plants per replicated habitat in LCO1 and Old School were selected based on presence of four unrooted branches. Each unrooted branch within a plant randomly received one of four possible treatments: forced branch burial, branch lifting, procedural control, and no manipulation (total N= 60 genets and 240 ramets). Forced burial was implemented to mimic sand burial and evaluate rooting probability and performance in both habitats. Branch lifting was applied to prevent sand burial and evaluate demography of unrooted branches in both habitats. The procedural control served to evaluate wire effects on ramet demography. The control provided vital and rooting rates of branches in natural conditions. Road populations exhibited larger crown area and higher monthly diameter (controlled by initial diameter) and higher monthly length growth rates compared to scrub populations. Rooting probability was only affected by treatment one (buried wire) not habitat or site. Forced sand burial increased rooting (67 % after forced contact vs. 20-30 % for other treatments). Rooted branches did not exhibit variation in survival, growth, or fecundity compared to unrooted branches. Old School populations exhibited larger crown area, higher monthly diameter and monthly length growth rates compared to LC01 populations. Prescribed fires killed several plants explaining significantly higher branch survival at the unburned LC01 (66.1%) compared to recently burned Old School (36.2 %). LC01 populations exhibited higher fecundity and ramet survival compared to Old School populations. In February – December 2006, I describe the reproductive schedule at (LC01) in 10 road and 10 scrub plants. Monthly, I counted number of inflorescences and flowers per inflorescence (one inflorescence per plant) for each plant. Number of inflorescences per plant was highest between May and September and higher in road than in scrub. Our results indicate significant different demographic performance of P. myriophylla at plant and branch level between road and scrub habitats. A longer term study is needed to determine if the persistence of P. myriophylla is threatened by increasing roadside populations.
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Date Issued: 2007
Identifier: CFE0001982, ucf:47421
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001982

Title: UNDERSTANDING PLANT COMMUNITY COMPOSITION IN AGRICULTURAL WETLANDS: CONTEXT DEPENDENT EFFECTS AND PLANT INTERACTIONS.
Creator: Boughton, Elizabeth, Quintana-Ascencio, Pedro, University of Central Florida
Abstract / Description: Community composition results from an integrated combination of random processes, regional habitat spatial structure, local environmental conditions, and species interactions. For example, the outcome of plant interactions can change depending on local environmental conditions such as nutrient availability, land management, or herbivory intensity. In particular, plant interactions may vary between facilitation and competition depending on ecological context, with facilitation expected to be...
Show moreCommunity composition results from an integrated combination of random processes, regional habitat spatial structure, local environmental conditions, and species interactions. For example, the outcome of plant interactions can change depending on local environmental conditions such as nutrient availability, land management, or herbivory intensity. In particular, plant interactions may vary between facilitation and competition depending on ecological context, with facilitation expected to be prevalent under stressful conditions. I present the results of four studies that address different aspects of the community assemblage and dynamics emphasizing the synergistic effect of different processes. In the first, I investigated the importance of habitat isolation in determining species richness of wetlands with contrasting land use. The second describes an experiment to test the hypothesis that plant interactions with an unpalatable plant (Juncus effusus) would range from competition in ungrazed areas to facilitation in grazed areas and predicted that facilitative effects of Juncus would differ among functional groups of beneficiary species and be strongest when grazing was intense. In the third, I examine the community composition impacts of Juncus and predicted that Juncus would preserve functional diversity in grazed wetlands but that the effects of Juncus would vary along a grazing gradient. The fourth study investigated the relative importance of competition and nutrients in determining wetland invasion in two different land use types. Broadly, I demonstrate that the importance of different processes (habitat isolation, nutrient availability, competition/facilitation) to community composition is dependent on ecological conditions. This integrated view of community dynamics is interesting from a purely ecological perspective but also can be applied to understanding ecological problems such as exotic invasions and restoration of disturbed habitats.
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Date Issued: 2009
Identifier: CFE0002678, ucf:48234
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002678

Title: SPECIES COMPOSITION AND SPATIOTEMPORAL PATTERN OF THE SEED BANK AND VEGETATION IN NATIVE AND DEGRADED FLORIDA ROSEMARY SCRUB.
Creator: Navarra, Jennifer, Quintana-Ascencio, Pedro, University of Central Florida
Abstract / Description: The soil seed bank plays a dynamic role in the regeneration of plant communities after natural and anthropogenic disturbance. In this thesis, I addressed how disturbances influence the vegetation and seed bank of Florida rosemary scrub. In Chapter One I evaluated changes in species composition and spatiotemporal pattern of the vegetation and seed bank along a gradient of disturbance. During the summers and winters of 2007-2009 percent ground cover and seed bank species composition were...
Show moreThe soil seed bank plays a dynamic role in the regeneration of plant communities after natural and anthropogenic disturbance. In this thesis, I addressed how disturbances influence the vegetation and seed bank of Florida rosemary scrub. In Chapter One I evaluated changes in species composition and spatiotemporal pattern of the vegetation and seed bank along a gradient of disturbance. During the summers and winters of 2007-2009 percent ground cover and seed bank species composition were assessed among replicates of three vegetation types subjected to minimal, moderate, and extreme anthropogenic disturbance (native rosemary scrub, degraded scrub, and agriculturally improved pasture, respectively). These vegetation types shared the same soil and topographic characteristics but differed in disturbance history. I found that species composition and spatial pattern varied with disturbance. In pastures the compositional and structural characteristics of rosemary scrub were lost and only native scrub species able to evade herbivory persisted in this community. Native and degraded scrub differed most from each other in species abundances and spatial pattern. Degraded scrub showed highest abundance of subshrubs and a spike moss species, while rosemary scrub was dominated by shrubs. The seed banks of scrub herbs in degraded scrub had a tendency towards a random spatial distribution that lacked association with aboveground cover. Conversely, rosemary scrub seed banks tended to have an aggregated distribution and were associated with occurrence of conspecific species aboveground, litter, and shrub cover. These results indicated a change in the spatial heterogeneity of the seed banks of scrub herbs in degraded scrub. In Chapter Two I evaluated changes in seed bank density with time-since-fire in native rosemary scrub. Due to large pulses of recruitment immediately after fire and population decline with time-since-fire, I predicted seed density with time-since-fire would follow a unimodal function with low density in early and late years post-fire, and highest density at intermediate time-since-fire. I compared seed density data among sites with different time-since-fire: two sites each of three, six, ten and 24 years time-since-fire and three long-unburned sites (> 24 years). Variability in seed bank composition and density increased with time-since-fire and only recently burned stands were distinctly different from the other time-since-fire age classes. Some species and functional groups did exhibit a quadratic or cubic association to time-since-fire (ruderal herbs, subshrubs, Ceratiola ericoides, Lechea cernua, Paronychia chartacea, Phyllanthus tenellus); however, timing of the peak in seed density varied depending on life span and age of reproductive maturity. Scrub herbs were the most abundant functional group in the seed bank and showed highest density in the first ten years post-fire. This pattern corresponds to the pattern of aboveground species abundance and suggests abundances above- and belowground are closely linked. Understanding the dynamics of the seed bank in both naturally and anthropogenically disturbed communities in Florida rosemary scrub is important for the restoration of scrub habitat and management of existing populations of endangered and threatened scrub species endemic to the Lake Wales Ridge in central Florida.
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Date Issued: 2010
Identifier: CFE0003108, ucf:48620
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003108

Title: Spatial distribution and abundance of large green turtles on foraging grounds in the Florida Keys, USA.
Creator: Welsh, Ryan, Mansfield, Kate, Quintana-Ascencio, Pedro, Gorham, Jonathan, University of Central Florida
Abstract / Description: Discerning distribution, density, and abundance of organisms is essential for conservation and management of imperiled species. However, simple counts of sampled individuals are often not adequate to make such estimates, this is especially true for large and highly mobile marine animals. Green turtles (Chelonia mydas) are a highly migratory, long-lived, late-maturing, marine megafauna, that is beginning to recover from severe global population declines. Distance sampling techniques can be...
Show moreDiscerning distribution, density, and abundance of organisms is essential for conservation and management of imperiled species. However, simple counts of sampled individuals are often not adequate to make such estimates, this is especially true for large and highly mobile marine animals. Green turtles (Chelonia mydas) are a highly migratory, long-lived, late-maturing, marine megafauna, that is beginning to recover from severe global population declines. Distance sampling techniques can be used to generate estimates of abundance of green turtles in foraging grounds which have been relatively unstudied in the Northeastern Atlantic basin, filling in important data gaps in a species that is of critical conservation concern. The Quicksands foraging grounds located west of Key West, Florida, USA is used by both sub-adult and adult green turtles. Standardized transects were performed 18 times between 2006 (-) 2018, and using the collected data; abundances, spatial distribution and evidence of spatial segregation were generated through density surface models and null mode analysis. Densities of foraging green turtles rival some of the largest densities known in the world. Spatial segregation of the two size classes is evident on the foraging ground and may be attributed to differing predator detection and avoidance strategies of the size classes Finally, given the high densities of animals found on the foraging grounds and the rise in general population levels of green turtles and drop in population of green turtle predators (i.e. large sharks), concern is raised for the long term sustainably of the Quicksands seagrass pastures.
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Date Issued: 2019
Identifier: CFE0007874, ucf:52767
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007874

Title: Hydrodynamic Limitations and the Effects of Living Shoreline Stabilization on Mangrove Recruitment along Florida Coastlines.
Creator: Pilato, Christian, Walters, Linda, Kibler, Kelly, Quintana-Ascencio, Pedro, University of Central Florida
Abstract / Description: The recruitment success of mangroves is influenced by a variety of factors, including propagule availability, desiccation, herbivory, and hydraulic habitat limitations. Hydrodynamic forces (waves and currents) act as obstacles to mangrove recruitment, restricting the successful colonization of mangrove species. We evaluated the biological and physical limitations to mangrove recruitment through monthly shoreline surveys and lateral pull-tests. Surveys followed mangroves from propagule release...
Show moreThe recruitment success of mangroves is influenced by a variety of factors, including propagule availability, desiccation, herbivory, and hydraulic habitat limitations. Hydrodynamic forces (waves and currents) act as obstacles to mangrove recruitment, restricting the successful colonization of mangrove species. We evaluated the biological and physical limitations to mangrove recruitment through monthly shoreline surveys and lateral pull-tests. Surveys followed mangroves from propagule release through recruitment along the shorelines of De Soto National Memorial (Bradenton, FL), capturing differences in propagule availability and recruitment along natural areas and across differing forms of shoreline stabilization ((")living shorelines(") and revetments). Propagule densities were highest along (")living shorelines("), followed by natural areas and revetments. Seedling densities were similar across treatments, mirroring densities found in disturbed mangrove systems in the Philippines ((<)1 seedling per m2). Pull-tests, simulating wave forces, quantified the physical thresholds for uprooting Rhizophora mangle and Avicennia germinans seedlings in both the greenhouse and field. Uprooting susceptibility significantly decreased with increased seedling biomass and age. A. germinans displayed a lower force to removal than R. mangle, but showed a greater increase in uprooting force with increases in size. Surrounding vegetation and canopy cover were not found to significantly affect the uprooting force of either species. Pull-test results were used in conjunction with drag coefficients from the literature to calculate flow velocities where mangroves would become susceptible to dislodgement from hydrodynamic forces. Seedlings tested would become susceptible at velocities of 7.33 (&)#177; 2.07 m/s for A. germinans and 5.40 (&)#177; 1.59 m/s for R. mangle. The rapid increase in force to removal shows the importance of disturbances, such as erosion, driving seedling dislodgment at the local scale. This research strengthens our understanding of the physical conditions conducive to successful recruitment under hydrodynamic stressors and provides insight into how a common restoration method can influence mangrove recruitment.
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Date Issued: 2019
Identifier: CFE0007899, ucf:52748
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007899

Title: Do per-capita impact or abundance dominate the impact of an invader? Interactions among neighboring species in context-dependent competition.
Creator: Li, Haoyu, Quintana-Ascencio, Pedro, Jenkins, David, Boughton, Elizabeth, University of Central Florida
Abstract / Description: Evaluating relative species competitive strength is a central question in community ecology, with strong implications for invasion ecology. Models assessing invader success consider three components: distribution, abundance and per-capita impact. However, relative strength and interactions among these factors remain unclear when applying to specific invasion scenarios. We hypothesized that performance of native and non-native species will vary as a function of direct and indirect effects at...
Show moreEvaluating relative species competitive strength is a central question in community ecology, with strong implications for invasion ecology. Models assessing invader success consider three components: distribution, abundance and per-capita impact. However, relative strength and interactions among these factors remain unclear when applying to specific invasion scenarios. We hypothesized that performance of native and non-native species will vary as a function of direct and indirect effects at different abundances and scales. We conducted a replacement experiment between two dominant grasses in subtropical grasslands (the native Axonopus fissifolius and the non-native Paspalum notatum) in central Florida, USA. Thirty fenced plots (1 m x 3 m each) representing a gradient (15 levels) of increasing non-native groundcover and decreasing native groundcover were set up in November 2017. We transplanted individuals of these two species in subplots (12 subplots and 36 transplants per plot; 1080 plants in total) in a 2*2 factorial design (mixed /single focal species * 2/4 transplants per subplot). Leaf length/number and plant biomass were evaluated at the beginning and end of the experiment along with plot species composition and soil nutrients. Over 92% of transplants of each grass species survived until harvest (11 months). There were significant differences in leaf length, leaf number and plant biomass between conspecific/allospecific subplots. Both P. notatum and A. fissifolius performed better when transplanted in non-native P. notatum subplots. There were also interactions between conspecific/allospecific subplot treatment (direct effects) and the gradient of increasing Paspalum notatum /decreasing Axonopus fissifolius groundcover (indirect effects) treatments. Increasing P. notatum in the whole plot made environments more favorable for both grass species. Effects were consistent for leaf length/number and biomass of the two focal species. More comprehensive evaluation on indirect effects need to be considered when examining competition between non-native species and native species.
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Date Issued: 2019
Identifier: CFE0007487, ucf:52685
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007487

Title: Does the journey matter more than the destination? The contribution of geospatial characteristics and local variables to invasive Pomacea maculata distribution across ranchland wetlands.
Creator: Pierre, Steffan, Quintana-Ascencio, Pedro, Jenkins, David, Boughton, Elizabeth, University of Central Florida
Abstract / Description: Geospatial characteristics such as isolation and avenues of connectivity influence an invader's pattern of dispersal and distribution. However many examinations of invasion success ignore the contribution of dispersal to patterns of invasion and focus only on the local environmental/habitat factors. This study examines the interaction of geospatial characteristics, that may influence dispersal, and local environmental factors, that may govern successful occupation, on the likelihood of...
Show moreGeospatial characteristics such as isolation and avenues of connectivity influence an invader's pattern of dispersal and distribution. However many examinations of invasion success ignore the contribution of dispersal to patterns of invasion and focus only on the local environmental/habitat factors. This study examines the interaction of geospatial characteristics, that may influence dispersal, and local environmental factors, that may govern successful occupation, on the likelihood of invasion (invasability) of wetlands within an agriculturally modified landscape. I examined the current invasion of seasonal wetlands in south-central Florida ranchland by non-native apple snails (Pomacea maculata (Ampullariidae)) as a model system for understanding this interaction. I surveyed spatial occurrence of P. maculata in 171 wetlands in 2014 and found they occurred in 43% of wetlands surveyed. I evaluated how occurrence was related to geospatial variables (proximity to propagule sources, shoreline complexity, interwetland distance, elevation, area and ditch presence) and wetland characteristics (pH, water hardness, conductivity and soil type) for 95 wetlands. Presence of ditch connections and more neutral water pH were associated with P. maculata occurrence. I did not find evidence that Euclidean distance and minimum ditch distance were associated with P. maculata occurrence. I also performed a 5 month field experiment where I translocated snails to previously occupied and non-occupied wetlands and measured snail survival and growth (20 wetlands from November to March). This experiment evaluated if non-occurrence during survey was more likely to be associated with unfavorable habitat conditions or dispersal limitation. Wetland pH and water hardness explained variation in P. maculata survival, and wetland pH best explained growth. I did not find evidence that prior occupancy affected the snail survival and growth, which suggests previously unoccupied wetlands are due to dispersal limitation. These results emphasize that man-made conduits can increase permeability of the landscape, facilitating the dispersal and introduction of nonnative species and the need for the inclusion of dispersal metrics in understanding invasive species distribution.
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Date Issued: 2015
Identifier: CFE0006374, ucf:51527
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006374

Title: Effects of harmful algal blooms caused by Aureoumbra lagunensis (brown tide) on larval and juvenile life stages of the eastern oyster (Crassostrea virginica).
Creator: Makris, Panagiota, Walters, Linda, Quintana-Ascencio, Pedro, Scarpa, John, University of Central Florida
Abstract / Description: Harmful algal blooms caused by the marine microalga Aureoumbra lagunensis have been associated with negative impacts on marine fauna, both vertebrate and invertebrate. Within the Indian River Lagoon (IRL) estuary system along Florida's east coast, blooms of A. lagunensis in excess of 1(&)#215;106 cells mL-1 have occurred along with higher than average salinities ((>)35 PSU) during times of peak reproduction and growth for the eastern oyster Crassostrea virginica. Field and laboratory studies...
Show moreHarmful algal blooms caused by the marine microalga Aureoumbra lagunensis have been associated with negative impacts on marine fauna, both vertebrate and invertebrate. Within the Indian River Lagoon (IRL) estuary system along Florida's east coast, blooms of A. lagunensis in excess of 1(&)#215;106 cells mL-1 have occurred along with higher than average salinities ((>)35 PSU) during times of peak reproduction and growth for the eastern oyster Crassostrea virginica. Field and laboratory studies were used to investigate the effects of A. lagunensis and high salinities on early life stages of eastern oysters, late pediveliger to early juvenile. Natural recruitment of C. virginica within Mosquito Lagoon (northern IRL) from 2013 to 2015 was negatively associated with blooms of A. lagunensis ((>)1(&)#215;105 cells mL-1) and high salinities ((>)35 PSU), but recruitment of barnacle competitors was not. Larval settlement, tested using recirculating raceway flumes, was affected both by A. lagunensis and high salinities. Additionally, survival and growth rates of juvenile C. virginica were tested following one-week laboratory exposure to A. lagunensis and subsequent transplantation to the field for four weeks. Survival of juvenile oysters was negatively correlated with A. lagunensis and time (80% survival for A. lagunensis exposure and 90% survival when exposed to Isochrysis galbana control). Our results indicated negative impacts of Aureoumbra lagunensis on larval and juvenile eastern oysters during the term of the experiment. Oyster recruitment and growth continued during and following exposure to bloom concentrations of A. lagunensis, but at reduced rates.
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Date Issued: 2016
Identifier: CFE0006535, ucf:51309
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006535

Title: Quantifying the effects of boat wakes on intertidal oyster reefs in a shallow estuary.
Creator: Campbell, Donna, Walters, Linda, Quintana-Ascencio, Pedro, Jachec, Steven, University of Central Florida
Abstract / Description: There have long been concerns about the negative impacts of recreational boating activity in the Indian River Lagoon system (IRL), especially in Mosquito Lagoon (ML), the northernmost part of the IRL. My research is focused on the impacts of boat wakes on intertidal reefs formed by the eastern oyster, Crassostrea virginica. There has been a 24% loss of oyster habitat in ML since 1943, where natural oyster reefs have been replaced by dead oyster reefs which do not serve the same ecological...
Show moreThere have long been concerns about the negative impacts of recreational boating activity in the Indian River Lagoon system (IRL), especially in Mosquito Lagoon (ML), the northernmost part of the IRL. My research is focused on the impacts of boat wakes on intertidal reefs formed by the eastern oyster, Crassostrea virginica. There has been a 24% loss of oyster habitat in ML since 1943, where natural oyster reefs have been replaced by dead oyster reefs which do not serve the same ecological function. While there is anecdotal and correlative evidence that this loss is a result of boat wakes, no studies to date have confirmed dead reefs can be a direct result of boat wakes. Therefore, I addressed the following questions: (1) What wake heights are generated by a range of boat types, and (2) What amount of oyster movement and erosion occurs as a result of these boat wakes? A series of boat pass experiments addressed the first question; these results were utilized in experiments at Florida Institute of Technology's wave tank to observe sediment erosion and oyster movement as a result of specific wake heights. Model selection was used for both the field and wave tank experiments to determine which variables contributed most to explaining the wake heights, erosion, and oyster movement that occurred. Wake heights ranging from 0.05 cm to 20.80 cm were documented contacting the oyster reefs from the boat passes, with a mean of 2.95 cm. Boat type was less important than speed or distance when determining wake height. My wave tank results document that wake heights as small as 2 cm contacting oysters are capable of moving individual and clusters of oysters. Minimum distances for boats to travel in order to maintain wakes smaller than 2 cm at reefs are suggested for management purposes based on regression equations. This could minimize the amount of movement that occurs when oysters are subjected to boat wakes. The results of this study can help resource managers implement boating policies in Mosquito Lagoon, and contribute greatly to conserving this important ecosystem engineer.
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Date Issued: 2015
Identifier: CFE0005584, ucf:50242
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005584

Title: Modeling and analysis of a three-species food web with facilitated and intraguild predation.
Creator: Castro, Joshua, Weishampel, John, Quintana-Ascencio, Pedro, Nevai, A, University of Central Florida
Abstract / Description: Biotic interactions are known to shape natural community assemblages and biodiversity. Positive interactions such as facilitation have recently received attention in ecological food webs. Mechanistic models have improved our understanding of these complex food web interactions. Here, focus is given to a three-species food web system with a beach dune natural community in mind. In the last decade, there has been a series of studies investigating intraguild predation between two major...
Show moreBiotic interactions are known to shape natural community assemblages and biodiversity. Positive interactions such as facilitation have recently received attention in ecological food webs. Mechanistic models have improved our understanding of these complex food web interactions. Here, focus is given to a three-species food web system with a beach dune natural community in mind. In the last decade, there has been a series of studies investigating intraguild predation between two major loggerhead sea turtle nest predators, North American raccoons and Atlantic ghost crabs. Studies have also highlighted that ghost crab predation assists raccoons in finding nests (i.e., facilitated predation). However, the combined effects of these two intraguild interactions and their consequences on nests have not been examined explicitly. The aims of this study were to (i) develop a three-species, ordinary differential equation model (ii) implement a sensitivity analysis to understand the influence of facilitation and other factors in driving species richness and abundance and (iii) characterize the dynamic interactions between intraguild predators and their effects on a shared resource. Interactions between ghost crabs and sea turtle eggs and facilitation can yield a wide variety of species abundance responses and were influential factors in the model. I found that high secondary sea turtle egg depredation and low facilitated predation by raccoons led to three species co-existence regions in the model. Controlling for nest predators at higher abundance levels showed that ghost crabs had a larger negative effect on sea turtle egg abundance responses when compared to raccoons. This suggests that interactions between sea turtle eggs and ghost crabs appear to be important and potential sea turtle nest management implications are discussed such as the use of ghost crab exclusion devices.
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Date Issued: 2015
Identifier: CFE0005771, ucf:50074
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005771

Title: Effects of biotic interactions on coastal wetland communities with applications for restoration.
Creator: Donnelly, Melinda, Walters, Linda, Quintana-Ascencio, Pedro, Weishampel, John, University of Central Florida
Abstract / Description: Coastal wetland plants serve as ecological engineers in a physiologically stressful environment and the loss of coastal wetlands can cause negative effects throughout the estuarine system. Due to increased degradation of coastal habitats worldwide, interest in restoration has increased around the world. An understanding of the biotic processes affecting species distribution and diversity is critical for future conservation, management, and restoration of coastal wetlands. The purpose of my...
Show moreCoastal wetland plants serve as ecological engineers in a physiologically stressful environment and the loss of coastal wetlands can cause negative effects throughout the estuarine system. Due to increased degradation of coastal habitats worldwide, interest in restoration has increased around the world. An understanding of the biotic processes affecting species distribution and diversity is critical for future conservation, management, and restoration of coastal wetlands. The purpose of my study was to test the effects of biotic interactions on native coastal wetland plants and determine how these interactions may be incorporated into current and future restoration projects. I had three primary goals for my dissertation. First, I evaluated the effectiveness of natural regeneration of coastal wetland communities following hydrological restoration. Second, I examined effects of biotic interactions between mangroves and other wetland species by experimentally testing: 1) trapping capabilities of early successional plant species on Rhizophora mangle propagules, 2) effects of pre-dispersal propagule damage on native mangrove species, 3) facilitative and competitive interactions between the plants Rhizophora mangle, Batis maritima, Sarcocornia perennis, and the fiddler crab, Uca pugilator using mesocosms. Third, I evaluated the combined effects of biotic and abiotic interactions on survival and growth of R. mangle propagules during their first year of establishment using a manipulative field experiment. Results from my study increase our knowledge of the importance of biotic interactions in coastal wetland communities, their role in early successional stages, and have direct applications to coastal wetland restoration and management.
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Date Issued: 2014
Identifier: CFE0005483, ucf:50344
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005483

Title: Mathematical Investigation of the Spatial Spread of an Infectious Disease in a Heterogeneous Environment.
Creator: Gaudiello, Arielle, Shuai, Zhisheng, Nevai, A, Song, Zixia, Mohapatra, Ram, Quintana-Ascencio, Pedro, University of Central Florida
Abstract / Description: Outbreaks of infectious diseases can devastate a population. Researchers thus study the spread of an infection in a habitat to learn methods of control. In mathematical epidemiology, disease transmission is often assumed to adhere to the law of mass action, yet there are numerous other incidence terms existing in the literature. With recent global outbreaks and epidemics, spatial heterogeneity has been at the forefront of these epidemiological models.We formulate and analyze a model for...
Show moreOutbreaks of infectious diseases can devastate a population. Researchers thus study the spread of an infection in a habitat to learn methods of control. In mathematical epidemiology, disease transmission is often assumed to adhere to the law of mass action, yet there are numerous other incidence terms existing in the literature. With recent global outbreaks and epidemics, spatial heterogeneity has been at the forefront of these epidemiological models.We formulate and analyze a model for humans in a homogeneous population with a nonlinear incidence function and demographics of birth and death. We allow for the combination of host immunity after recovery from infection or host susceptibility once the infection has run its course in the individual. We compute the basic reproduction number, R0, for the system and determine the global stability of the equilibrium states. If R0(<)= 1, the population tends towards a disease-free state. If R0 (>)1, an endemic equilibrium exists, and the disease is persistent in the population. This work provides the framework needed for a spatially heterogeneous model. The model is then expanded to include a set of cities (or patches), each of which is structured from the homogeneous model. Movement is introduced, allowing travel between the cities at different rates. We assume there always exists a potentially non-direct route between two cities, and the movement need not be symmetric between two patches. Further, each city has its own nonlinear incidence function, demographics, and recovery rates, allowing for realistic interpretations of country-wide network structures. New global stability results are established for the disease-free equilibrium and endemic equilibrium, the latter utilizing a graph theoretic approach and Lyapunov functions. Asymptotic profiles are determined for both the disease-free equilibrium and basic reproduction number as the diffusion of human individuals is faster than the disease dynamics. A numerical investigation is performed on a star network, emulating a rural-urban society with a center city and surrounding suburbs. Numerical simulations give rise to similar and contrasting behavior for symmetric movement to the proposed asymmetric movement. Conjectures are made for the monotonicty of the basic reproduction number in terms of the diffusion of susceptible and infectious individuals. The limiting behavior of the system as the diffusion of susceptibles halts is shown to experience varying behavior based on the location of hot spots and biased movement.
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Date Issued: 2019
Identifier: CFE0007637, ucf:52463
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007637

Title: The effects of urbanization on cypress (Taxodium distichum) in central Florida.
Creator: McCauley, Lisa, Jenkins, David, Quintana-Ascencio, Pedro, Hoffman, Eric, Ewel, Kathy, University of Central Florida
Abstract / Description: Urbanization is accelerating in the United States and is contributing to fragmentation of natural habitats, causing changes in species composition and declines in native species. Human population growth in Orlando is typical of growth in the southeastern United States and throughout the range of cypress (Taxodium distichum). Orlando has numerous isolated cypress wetlands, called cypress domes, and many remain among the current urbanized area. This makes Orlando ideal to study the effects of...
Show moreUrbanization is accelerating in the United States and is contributing to fragmentation of natural habitats, causing changes in species composition and declines in native species. Human population growth in Orlando is typical of growth in the southeastern United States and throughout the range of cypress (Taxodium distichum). Orlando has numerous isolated cypress wetlands, called cypress domes, and many remain among the current urbanized area. This makes Orlando ideal to study the effects of urbanization on cypress domes. Specifically, I tested how urbanization and its effects on fragmentation, hydrology, and fire regime) affected (a) the numbers and spatial pattern of cypress domes in central Florida and (b) the recruitment of cypress within cypress domes. Analysis of historical loss found over 3,000 cypress domes identified in images from1984, of which 26% were lost or degraded (i.e., no longer cypress-dominated) by 2004. Due to changed land use, many remaining cypress domes, formerly surrounded by natural lands, have become surrounded by urban lands causing spatial clustering and homogenization. Surprisingly, I found that both natural and urban cypress domes showed lower recruitment than agricultural cypress domes, where the natural fire regime has not been altered. The probability of cypress recruitment in cypress domes urbanized for more than 20 years is very low. Previous to that, cypress tends to recruit on the edge of cypress domes where there is less competition and hydrological conditions are more favorable. I estimate that only ~50% of the current cypress domes are recruiting and the existence of those wetlands are tied to the lifespan of the current adults. By 2104, I estimate that ~89% of the cypress domes currently recruiting will fail to recruit. I believe that reducing urban sprawl and restoring the natural fire regime to natural cypress domes will mitigate the current fate of cypress domes. Without this, cypress in isolated wetlands in central Florida, and providing Orlando urbanization is typical, throughout urbanized areas of the range, could be at risk. Cypress in urban areas will be then relegated to riparian zones and with unknown consequences for the species that utilize the former cypress dome habitat.
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Date Issued: 2011
Identifier: CFE0004136, ucf:49065
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004136

Title: Relating ancient Maya land use legacies to the contemporary forest of Caracol, Belize.
Creator: Hightower, Jessica, Weishampel, John, Quintana-Ascencio, Pedro, VonHolle, Mary, Chase, Arlen, University of Central Florida
Abstract / Description: Human land use legacies have significant and long lasting impacts across landscapes. However, investigating the impacts of ancient land use legacies ((>)400 years) remains problematic due to the difficulty in detecting ancient land uses, especially those beneath dense canopies. The city of Caracol, one of the most important Maya archaeological sites in Belize, was abandoned after the collapse of the Maya civilization (ca. A.D. 900), leaving behind numerous structures, causeways, and...
Show moreHuman land use legacies have significant and long lasting impacts across landscapes. However, investigating the impacts of ancient land use legacies ((>)400 years) remains problematic due to the difficulty in detecting ancient land uses, especially those beneath dense canopies. The city of Caracol, one of the most important Maya archaeological sites in Belize, was abandoned after the collapse of the Maya civilization (ca. A.D. 900), leaving behind numerous structures, causeways, and agricultural terraces that persist beneath the dense tropical forest of western Belize. LiDAR (Light Detection and Ranging) technology enables detection of below canopy Maya archaeological features, providing an ideal opportunity to study the effects of ancient land use legacies on contemporary tropical forest composition. LiDAR also provided us with a detailed record of the 3-dimensional forest structure over the 200 km2 study area. This allowed the investigation how ancient land uses continue to impact both forest composition, in terms of tree species, and forest structure. I recorded tree species over four land use categories: 1) structures, 2) causeways, 3) terraced, and 4) non-terraced land. Using non-metric multidimensional scaling (NMS) and multi-response permutation procedures (MRPP) to test for differences between the classes, I found significantly distinct tree communities associated with the presence of terraces and the underlying topography. Terraced slopes appear to function as micro-valleys on the side of a hill, creating an environmental "bridge" between slope and valley tree communities. Tree species composition over causeways and structures was also found to be significantly different from terraced and non-terraced plots. Forest structure was assessed by extracting LiDAR points for terraced (n=150) and non-terraced (n=150) 0.25 ha plots. I calculated average canopy height, canopy closure, and vertical diversity from the height bins of the LiDAR points, using slope, elevation, and aspect as covariates. Using PerMANOVA I determined that forest structure over terraces was significantly different from non-terraced land. Terraces appear to mediate the effect of slope, resulting in less structural variation between slope and non-sloped land. These results led to the conclusion that human land uses abandoned (>)1000 years ago continue to impact the contemporary forests.
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Date Issued: 2012
Identifier: CFE0004250, ucf:49497
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004250

Title: Factors limiting native species establishment on former agricultural lands.
Creator: Weiler-Lazarz, Annalisa, VonHolle, Mary, Quintana-Ascencio, Pedro, Neill, Christopher, Nickerson, David, University of Central Florida
Abstract / Description: Restoration of abandoned, nonnative species-dominated agricultural lands provides opportunities for conserving declining shrubland and grassland ecosystems. Land-use legacies, such as elevated soil fertility and pH from agricultural amendments, often persist for years and can favor nonnative species at the expense of native species. Understanding the factors that limit native species establishment on abandoned agricultural lands can provide important insights for restoration and conservation...
Show moreRestoration of abandoned, nonnative species-dominated agricultural lands provides opportunities for conserving declining shrubland and grassland ecosystems. Land-use legacies, such as elevated soil fertility and pH from agricultural amendments, often persist for years and can favor nonnative species at the expense of native species. Understanding the factors that limit native species establishment on abandoned agricultural lands can provide important insights for restoration and conservation of native species on human-modified lands. I conducted two field experiments on abandoned agricultural lands: a former pasture on Martha's Vineyard, MA and a former citrus grove at Merritt Island National Wildlife Refuge (MINWR) in Titusville, FL. In these experiments I tested how soil chemical properties affect native and nonnative species abundance and how different methods of removing nonnative, invasive species affect native and nonnative species abundance. In the first experiment, specifically I tested how restoration treatments affect competition between existing nonnative agricultural plant species and native plant species that are targets for sandplain grassland restoration on Martha's Vineyard, MA. At MINWR, I examined how lowering soil fertility with carbon additions and lowering soil pH by applying sulfur affects nonnative species richness and cover (in two former citrus groves that were historically scrub/scrubby flatwoods. Overall, I found that biotic factors, such as competition with nonnative species, play a stronger role in limiting native species establishment than soil chemical properties. Likewise, control of nonnative, invasive species is most effective with mechanical treatments to physically reduce cover, rather than altering soil chemical properties.
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Date Issued: 2012
Identifier: CFE0004323, ucf:49462
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004323

Title: Disturbance-Based Management and Plant Species Change in Massachusetts Sandplain Heathlands over the Past Two Decades.
Creator: Martin, Kirsten, VonHolle, Mary, Quintana-Ascencio, Pedro, Weishampel, John, University of Central Florida
Abstract / Description: Massachusetts sandplain heathlands are habitats of conservation concern, harboring many rare plant species and providing habitat for animals that depend on openlands. These heathlands are threatened by human development, shrub encroachment in the absence of disturbance, and potentially increasing soil nutrient levels. Sandplain heathlands are managed with prescribed fire, in order to maintain their open structure and maintain species diversity. In order to assess how past management was...
Show moreMassachusetts sandplain heathlands are habitats of conservation concern, harboring many rare plant species and providing habitat for animals that depend on openlands. These heathlands are threatened by human development, shrub encroachment in the absence of disturbance, and potentially increasing soil nutrient levels. Sandplain heathlands are managed with prescribed fire, in order to maintain their open structure and maintain species diversity. In order to assess how past management was correlated with species change, I used a data set that spanned twenty years from three different heathlands in Massachusetts. I looked for correlations between management and species change. Correlations between species change and prescribed burning were very site, or microsite, specific, indicating that variables such as vegetation type and edaphic characteristics need to be taken into account before management is applied. Prescribed fire was also associated with an increase in ruderal species in one of the sites studied, indicating that there may be undesirable effects of prescribed fire in this system. Species diversity was negatively associated with shrub encroachment, reinforcing the importance of preventing shrubs from encroaching into these heathlands. I also found evidence that burning has not been a successful technique in preventing shrub encroachment in these sites. Lastly, the nitrophilic species Carex pensylvanica increased in all three sites, indicating that future studies should investigate the possibility that sandplain heathlands are currently experiencing nitrogen deposition beyond their critical loads.
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Date Issued: 2013
Identifier: CFE0004886, ucf:49677
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004886

Title: Cross-Continental Insights into Jaguar (Panthera onca) Ecology and Conservation.
Creator: Figel, Joseph, Noss, Reed, Quintana-Ascencio, Pedro, Jenkins, David, Quigley, Howard, University of Central Florida
Abstract / Description: The jaguar (Panthera onca) is a widely distributed large carnivore and the focal species of a range-wide connectivity initiative known as the jaguar conservation network (JCN). Comprised of ~83 Jaguar Conservation Units (JCUs) and ~75 corridors from northern Mexico to Argentina, the JCN functions as a conduit for jaguar movement and gene flow. Key linkages in the network are imperiled by human population growth, large-scale agriculture, highway expansion, and other infrastructural development...
Show moreThe jaguar (Panthera onca) is a widely distributed large carnivore and the focal species of a range-wide connectivity initiative known as the jaguar conservation network (JCN). Comprised of ~83 Jaguar Conservation Units (JCUs) and ~75 corridors from northern Mexico to Argentina, the JCN functions as a conduit for jaguar movement and gene flow. Key linkages in the network are imperiled by human population growth, large-scale agriculture, highway expansion, and other infrastructural development. Labeled (")corridors of concern,(") these vulnerable linkages are imperative to the maintenance of connectivity and genetic diversity throughout jaguar distribution. I take a multi-faceted approach to analyze conservation issues and identify potential solutions in three of the most vulnerable connections of the JCN. I estimate densities and assess local residents' perceptions of jaguars in a fragmented JCU in western Mexico, analyze 3 years of data from 275 camera-trap sites to evaluate jaguar habitat use in a corridor of concern in Colombia, and quantify the umbrella value of jaguars for endemic herpetofauna in Nuclear Central America, a ~ 370,000 km(&)#178; sub-region of the Mesoamerican biodiversity hotspot. My research produces the first jaguar density estimate in a JCU containing human population densities (>)50 people/km2 and provides the strongest support for jaguar association with wetlands collected to date. In Nuclear Central America, one of the most important yet vulnerable areas of the JCN, I demonstrate the umbrella value of this wide-ranging felid. I conclude with a discussion on the need to reevaluate extirpation thresholds of jaguars in human-use landscapes, to direct more research on wetlands as keystone habitats for jaguars, and to further assess the utility of umbrella analyses using jaguars as focal species to support holistic conservation planning.
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Date Issued: 2017
Identifier: CFE0006591, ucf:51258
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006591

Title: A mathematical model for feral cat ecology with application to disease.
Creator: Sharpe, Jeff, Nevai, A, Shuai, Zhisheng, Qi, Yuanwei, Quintana-Ascencio, Pedro, University of Central Florida
Abstract / Description: We formulate and analyze a mathematical model for feral cats living in an isolated colony. The model contains compartments for kittens, adult females and adult males. Kittens are born at a rate proportional to the population of adult females and mature at equal rates into adult females and adult males. Adults compete with each other in a manner analogous to Lotka-Volterra competition. This competition comes in four forms, classified by gender. Native house cats, and their effects are also...
Show moreWe formulate and analyze a mathematical model for feral cats living in an isolated colony. The model contains compartments for kittens, adult females and adult males. Kittens are born at a rate proportional to the population of adult females and mature at equal rates into adult females and adult males. Adults compete with each other in a manner analogous to Lotka-Volterra competition. This competition comes in four forms, classified by gender. Native house cats, and their effects are also considered, including additional competition and abandonment into the feral population. Control measures are also modeled in the form of per-capita removal rates. We compute the net reproduction number (R_0) for the colony and consider its influence. In the absence of abandonment, if R_0(>)1, the population always persists at a positive equilibrium and if R_0 (<)= 1, the population always tends toward local extinction. This work will be referred to as the core model.The model is then expanded to include a set of colonies (patches) such as those in the core model (this time neglecting the effect of abandonment). Adult females and kittens remain in their native patch while adult males spend a fixed proportion of their time in each patch. Adult females experience competition from both the adult females living in the same patch as well as the visiting adult males. The proportion of adult males in patch j suffer competition from both adult females resident to that patch as well the proportion of adult males also in the patch. We formulate a net reproduction number for each patch (a patch reproduction number) R_j. If R_j(>)1 for at least one patch, then the collective population always persists at some nontrivial (but possibly semitrivial) steady state. We consider the number of possible steady states and their properties. This work will be referred to as the patch model.Finally, the core model is expanded to include the introduction of the feline leukemia virus. Since this disease has many modes of transmission, each of which depends on the host's gender and life-stage, we regard this as a model disease. A basic reproduction number R_0 for the disease is defined and analyzed. Vaccination terms are included and their role in disease propagation is analyzed. Necessary and sufficient conditions are given under which the disease-free equilibrium is stable.
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Date Issued: 2016
Identifier: CFE0006502, ucf:51389
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006502

Title: Habitat selection in transformed landscapes and the role of novel ecosystems for native species persistence.
Creator: Sanchez Clavijo, Lina, Quintana-Ascencio, Pedro, Noss, Reed, Weishampel, John, Rodewald, Amanda, University of Central Florida
Abstract / Description: To understand native species persistence in transformed landscapes we must evaluate how individual behaviors interact with landscape structure through ecological processes such as habitat selection. Rapid, widespread landscape transformation may lead to a mismatch between habitat preference and quality, a phenomenon known as ecological traps that can have negative outcomes for populations. I applied this framework to the study of birds inhabiting landscapes dominated by forest remnants and...
Show moreTo understand native species persistence in transformed landscapes we must evaluate how individual behaviors interact with landscape structure through ecological processes such as habitat selection. Rapid, widespread landscape transformation may lead to a mismatch between habitat preference and quality, a phenomenon known as ecological traps that can have negative outcomes for populations. I applied this framework to the study of birds inhabiting landscapes dominated by forest remnants and shade coffee plantations, a tropical agroforestry system that retains important portions of native biodiversity. I used two different approaches to answer the question: What is the role of habitat selection in the adaptation of native species to transformed landscapes? First, I present the results of a simulation model used to evaluate the effects of landscape structure on population dynamics of a hypothetical species under two mechanisms of habitat selection. Then I present the analyses of seven years of capture-mark-recapture and resight data collected to compare habitat preference and quality between shade coffee and forest for twelve resident bird species in the Sierra Nevada de Santa Marta (Colombia). I provide evidence for the importance of including the landscape context in the evaluation of ecological traps and for using long-term demographic data when evaluating the potential of novel ecosystems and intermediately-modified habitats for biodiversity conservation. Beyond suggestions to improve bird conservation in shade coffee, my findings contribute to theory about ecological traps and can be applied to understand population processes in a wide variety of heterogeneous landscapes.
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Date Issued: 2016
Identifier: CFE0006494, ucf:51392
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006494

Title: Using Molecular Genetic and Demographic Tools to Improve Management of Ex Situ Avian Populations.
Creator: Ferrie, Gina, Hoffman, Eric, Parkinson, Christopher, Quintana-Ascencio, Pedro, Bettinger, Tamara, University of Central Florida
Abstract / Description: Small populations, specifically those that are isolated from others, are more prone to extinction than larger inter-connected populations. The risks that these small isolated populations face include loss of genetic diversity due to founder effects and inbreeding due to population bottlenecks, as well as demographic uncertainty due to fluctuating fecundity and mortality rates and impacts of external environmental factors. Ex situ populations, including those managed as conservation breeding...
Show moreSmall populations, specifically those that are isolated from others, are more prone to extinction than larger inter-connected populations. The risks that these small isolated populations face include loss of genetic diversity due to founder effects and inbreeding due to population bottlenecks, as well as demographic uncertainty due to fluctuating fecundity and mortality rates and impacts of external environmental factors. Ex situ populations, including those managed as conservation breeding programs with species recovery aims, as well as those that do not have reintroduction goals but are managed for long term population sustainability, suffer from the same extinction risks as small and isolated natural populations. Using three separate avian species which have different life histories and population structures, I investigated impacts of multiple genetic and demographic management strategies on these ex situ populations. I examined the use of molecular genetic datasets including microsatellites and single nucleotide polymorphisms (SNPs) to determine their utility for reconstructing pedigrees, examining individual relatedness within populations, and compared results of measuring genetic diversity through theoretical methods verses those obtained from a molecular dataset. These methods can then ultimately be applied to improve future management including improving studbook datasets and to measure actual loss of genetic diversity. I also used analytical strategies including population viability analysis to determine how management practices influence demographic parameters and determine the future probability of population extinction. The genetic and demographic analyses of both the historic management of an ex situ population, and its current status, are a first step in hypothesizing the potential directions for future management and understanding the likelihood of survival of an ex situ population.
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Date Issued: 2017
Identifier: CFE0006940, ucf:51670
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006940

Florida (3)	+ -
Florida scrub (2)	+ -
Indian River Lagoon (2)	+ -
anthropogenic disturbance (2)	+ -
demography (2)	+ -

disturbance (2)	+ -
facilitation (2)	+ -
restoration (2)	+ -
Ancient Agriculture (1)	+ -
Apalachicola (1)	+ -
Bachman's Sparrow (1)	+ -
Brachyhypopomus (1)	+ -
Budyko (1)	+ -
Colombia (1)	+ -
Communication (1)	+ -
Conservation planning (1)	+ -
Crassostrea virginica (1)	+ -
Crassostrea virgnica (1)	+ -
Ecology model (1)	+ -
Electric organ (1)	+ -
Electrogenesis (1)	+ -
Electroreception (1)	+ -
FeLV (1)	+ -
Felis catus (1)	+ -
Florida Grasshopper Sparrow (1)	+ -
Forest Ecology (1)	+ -
GRACE (1)	+ -
Grasshopper Sparrow (1)	+ -
Gulf of Mexico (1)	+ -
Gymnotiformes (1)	+ -

Quintana-Ascencio, Pedro (30)	+ -
University of Central Florida (30)	+ -
Weishampel, John (7)	+ -
Jenkins, David (6)	+ -
Walters, Linda (6)	+ -

Noss, Reed (5)	+ -
VonHolle, Mary (4)	+ -
Boughton, Elizabeth (3)	+ -
Hoffman, Eric (3)	+ -
Nevai, A (3)	+ -
Fauth, John (2)	+ -
Kibler, Kelly (2)	+ -
Roth, James (2)	+ -
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Bettinger, Tamara (1)	+ -
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