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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: Testing for indirect benefits of polyandry in the Florida green turtle.
Creator: Long, Christopher, Weishampel, John, Ehrhart, Llewellyn, Hoffman, Eric, University of Central Florida
Abstract / Description: Behavioral studies in the green turtle (Chelonia mydas) have indicated that promiscuous mating is commonplace. Though it has been shown that there is much variation in the rate of polyandry (females mating with multiple males), the drivers behind polyandry in this species are unknown. It has been speculated, but never demonstrated, that indirect benefits (fitness benefits resulting from offspring genetic diversity) play a role. However, previous tests of this hypothesis have limited scope of...
Show moreBehavioral studies in the green turtle (Chelonia mydas) have indicated that promiscuous mating is commonplace. Though it has been shown that there is much variation in the rate of polyandry (females mating with multiple males), the drivers behind polyandry in this species are unknown. It has been speculated, but never demonstrated, that indirect benefits (fitness benefits resulting from offspring genetic diversity) play a role. However, previous tests of this hypothesis have limited scope of inference due to lack of environmental control. In this thesis, I attempted to study the indirect benefits of polyandry in Archie Carr National Wildlife Refuge (ACNWR) green turtles, limiting environmental variation by selecting nests over two week periods in a small subset of the ACNWR. Through the use of highly polymorphic microsatellite markers, I show that 85.7% of ACNWR green turtle females mate with multiple males, the highest rate yet reported for green turtles. I was successful in limiting environmental variation; however, I was unable to make comparisons among nests with one or multiple fathers because of a limited sample size of single father nests. Regardless, my thesis provides preliminary evidence (number of males per nest) that the density of males off Florida's beaches may be relatively high, which is expected to be a driver behind the evolution of polyandry and likely plays a large role both in this population and the prevalence of multiple paternity in green turtles as a whole.
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Date Issued: 2013
Identifier: CFE0005029, ucf:50010
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005029

Title: Relating climate change to the nesting phenology and nest environment of marine turtles.
Creator: Schwoerer, Monette, VonHolle, Mary, Weishampel, John, Mansfield, Katherine, University of Central Florida
Abstract / Description: Ectotherms (including marine turtles) being especially sensitive to climate, are at risk to the accelerated rate of human-driven climate change. This study addresses two concerns associated with marine turtles and climate change (-) the relationship between the timing of marine turtle nesting and sea surface temperature; and the concern over the feminization of marine turtle populations due to rising sand temperatures. Previous studies of loggerhead sea turtles (Caretta caretta) and green sea...
Show moreEctotherms (including marine turtles) being especially sensitive to climate, are at risk to the accelerated rate of human-driven climate change. This study addresses two concerns associated with marine turtles and climate change (-) the relationship between the timing of marine turtle nesting and sea surface temperature; and the concern over the feminization of marine turtle populations due to rising sand temperatures. Previous studies of loggerhead sea turtles (Caretta caretta) and green sea turtles (Chelonia mydas) have documented the relationship between sea surface temperatures and nesting phenology. Earlier nesting behaviors in both species have been associated with warmer sea surface temperatures. Also, sex determination for marine turtles is temperature-dependent. Due to current sand temperatures, it is estimated that loggerhead (Caretta caretta) nests along the Atlantic coast of Florida already produce over 89% female hatchlings. Using shade to reduce nest temperature and increase the proportion of male hatchlings is one option for mitigating the impacts of climate change on marine turtle sex ratios. In this study, a 21-year (1988-2008) dataset of hawksbill sea turtle (Eretmochelys imbricata) nesting at Buck Island Reef National Monument, St. Croix, USVI was analyzed in a similar manner to previous studies. It was found that warmer sea surface temperatures were associated with longer nesting seasons and later median nesting dates. Additionally, a preliminary sand shading study was conducted in the first field season (2011) with a subsequent loggerhead nest shading study in the following field season (2012). Although hatching success was not significantly impacted, temperatures were significantly reduced in the majority of shaded nests. This practice may not be immediately applicable as a means of managing sex ratios, but it could be used to reverse the temperature effects of nest relocation.
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Date Issued: 2013
Identifier: CFE0005057, ucf:49973
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005057

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: An assessment of ecological processes in the Apalachicola estuarine system, Florida.
Creator: Smar, Daina, Hagen, Scott, Wang, Dingbao, Weishampel, John, University of Central Florida
Abstract / Description: The following is a compilation of field data collected in 2011 and 2012 in Apalachicola, FL as part of a five year study assessing the ecological effects of sea level rise in the northern Gulf of Mexico. Many coastal communities, both natural and developed, will soon be working to mitigate the effects of sea level rise, if they are not already doing so. This thesis investigates the natural patterns of the Apalachicola estuarine system through the collection and analysis of in situ water,...
Show moreThe following is a compilation of field data collected in 2011 and 2012 in Apalachicola, FL as part of a five year study assessing the ecological effects of sea level rise in the northern Gulf of Mexico. Many coastal communities, both natural and developed, will soon be working to mitigate the effects of sea level rise, if they are not already doing so. This thesis investigates the natural patterns of the Apalachicola estuarine system through the collection and analysis of in situ water, sediment, and biomass samples. Additionally, results of the field samples are presented and recommendations for additional sampling are given. The field methods and procedures developed in this study were designed to be repeated in other estuaries to build upon the work that has been conducted in Apalachicola. Water samples were tested for total suspended solids (TSS) and compared against hydrodynamic (tidal circulation and streamflow) and meteorological (wind and precipitation) characteristics. Streamflow was determined to influence a seasonal base level concentration of TSS. Wind strength and direction consistently influenced small TSS concentration fluctuations, an effect amplified by the shallow nature of the estuary. Tidal circulation appeared to have minor influences on TSS concentration fluctuations within the base level concentration range. Precipitation appeared to influence large TSS concentration fluctuations; however, due to limited data collection during storm events, more data is required to conclusively state this. Sediment cores throughout the lower Apalachicola River revealed that coarse particles settled out in upstream areas while fine particles tended to stay in suspension until low energy areas in the lower portions of the river or marsh system were reached. Finally, biomass samples were used to develop regression models utilizing remotely sensed data to predict biomass density in marsh areas with unprecedented accuracy. The documented patterns of this system are to be used as inputs and validation points to update an existing hydrodynamic model and to aid in the coupling and development of sediment transport and marsh equilibrium models. The field campaign developed and implemented here provides a foundation for this novel coupled modeling effort of estuarine systems. From the 2011 and 2012 sampling conducted, it is apparent that Apalachicola can be modeled as a closed system with river inflow and sediment influx as boundary conditions. Forcing local conditions should accurately represent the system. Ultimately, these models will be used to simulate future sea level rise scenarios and will provide useful decision making tools to coastal managers. Future work will include replicating water sampling in subsequent wet and dry seasons in Apalachicola, FL to confirm observed trends, in addition to implementing this sampling in Grand Bay, MS and Weeks Bay, AL. Additional biomass samples will be taken to validate the strong correlations found between remotely sensed data and in situ samples. In similar studies, it is recommended that water samples be taken to adequately represent influences from tidal cycles and riverine inflow. It is also recommended that spatially distributed biomass samples be taken to validate regression models.
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Date Issued: 2012
Identifier: CFE0004602, ucf:49920
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004602

Title: Evaluation of the three-dimensional patterns and ecological impacts of the invasive Old World climbing fern (Lygodium microphyllum).
Creator: Maldonado, Alexis, Weishampel, John, VonHolle, Mary, Hinkle, Charles, University of Central Florida
Abstract / Description: Invasion by non-native species has had significant ecological and economic impacts on a global scale. In the state of Florida, Old World climbing fern (Lygodium microphyllum) is an invasive plant listed by FLEPPC as a category one invader with significant ecological impacts that threaten native plant diversity. This species relies on existing vegetative structures for support to climb into the forest canopy and forms dense mats that cover tree crowns. This subsequently affects the resources...
Show moreInvasion by non-native species has had significant ecological and economic impacts on a global scale. In the state of Florida, Old World climbing fern (Lygodium microphyllum) is an invasive plant listed by FLEPPC as a category one invader with significant ecological impacts that threaten native plant diversity. This species relies on existing vegetative structures for support to climb into the forest canopy and forms dense mats that cover tree crowns. This subsequently affects the resources available to other species present. Quantifying the structural changes due to the presence of this species has proved logistically difficult, especially on a large spatial scale.Airborne LiDAR (Light Detection And Ranging) technology is a form of remote sensing that measures the elevation of surfaces over a site. In this study I utilized LiDAR to calculate various forest structure metrics at Jonathan Dickinson State Park (JDSP) in Hobe Sound, Florida across various management frequencies and densities of Old World climbing fern. These data were used to quantify the degree to which this invasive species alters forest structure across these two gradients. I also recorded species composition in the field to relate how Old World climbing fern impacts native plant diversity. Structural measurements including average canopy height, height of median energy (HOME), rugosity, canopy openness, and vertical structural diversity (LHDI) were calculated for a total of three hundred 0.25ha sites stratified by invasion density and management frequency.Using a combination of univariate and multivariate statistical analyses I found that the presence of Old World Climbing fern altered the physical structure of the forest communities itivinvades. Higher percent cover of Old World climbing fern decreased structural diversity while increased management effort was found to mitigate those impacts. The management for Old World Climbing fern was also found to impact both species richness and diversity at JDSP. I also demonstrated that there were several species that were not found and others that were more common in the presence of Old World climbing fern and that there was a relationship between management and what species were present. The results show that both Old World climbing fern and the management practices used to control it have had significant ecological impacts on the natural communities in South Florida.
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Date Issued: 2014
Identifier: CFE0005206, ucf:50651
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005206

Title: Effluent Water Quality Improvement Using Silt Fences and Stormwater Harvesting.
Creator: Gogo-Abite, Ikiensinma, Chopra, Manoj, Wanielista, Martin, Nam, Boo Hyun, Weishampel, John, University of Central Florida
Abstract / Description: Construction sites are among the most common areas to experience soil erosion and sediment transport due to the mandatory foundation tasks such as excavation and land grubbing. Thus, temporary sediment barriers are installed along the perimeter to prevent sediment transport from the site. Erosion and sediment transport control measures may include, but not limited to, physical and chemical processes such as the use of a silt fence and polyacrylamide product. Runoff from construction sites and...
Show moreConstruction sites are among the most common areas to experience soil erosion and sediment transport due to the mandatory foundation tasks such as excavation and land grubbing. Thus, temporary sediment barriers are installed along the perimeter to prevent sediment transport from the site. Erosion and sediment transport control measures may include, but not limited to, physical and chemical processes such as the use of a silt fence and polyacrylamide product. Runoff from construction sites and other impervious surfaces are routinely discharged into ponds for treatment before being released into a receiving water body. Stormwater harvesting from a pond for irrigation of adjacent lands is promoted as one approach to reducing pond discharge while supplementing valuable potable water used for irrigation. The reduction of pond discharge reduces the mass of pollutants in the discharge. In the dissertation, presented is the investigation of the effectiveness of temporary sediment barriers and then, development of a modeling approach to a stormwater harvesting pond to provide a comprehensive stormwater management pollution reduction assessment tool.The first part of the research presents the investigation of the performance efficiencies of silt fence fabrics in turbidity and sediment concentration removal, and the determination of flow-through-rate on simulated construction sites in real time. Two silt fence fabrics, (1) woven and the other (2) nonwoven were subjected to material index property tests and a series of field-scale tests with different rainfall intensities and events for different embankment slopes on a tilting test-bed. Collected influent and effluent samples were analyzed for sediment concentration and turbidity, and the flow-through-rate for each fabric was evaluated. Test results revealed that the woven and nonwoven silt fence achieved 11 and 56 percent average turbidity reduction efficiency, respectively. Each fabric also achieved 20 and 56 percent average sediment concentration removal efficiency, respectively. Fabric flow-through-rates were functions of the rainfall intensity and embankment slope. The nonwoven fabric exhibited higher flow-through-rates than the woven fabric in both field-scale and laboratory tests.In the second part of the study, a Stormwater Harvesting and Assessment for Reduction of Pollution (SHARP) model was developed to predict operation of wet pond used for stormwater harvesting. The model integrates the interaction of surface water and groundwater in a catchment area. The SHARP model was calibrated and validated with actual pond water elevation data from a stormwater pond at Miramar Lakes, Miramar, Florida. Model evaluation showed adequate prediction of pond water elevation with root mean square error between 0.07 and 0.12 m; mean absolute error was between 0.018 and 0.07 m; and relative index of agreement was between 0.74 and 0.98 for both calibration and validation periods. The SHARP model is capable of assessing harvesting safe-yield and discharge from a pond, including the prediction of the percentage of runoff into a harvesting pond that is not discharged.The combination of silt fence and/or polyacrylamide PAM before stormwater harvesting pond in a treatment train for the reduction of pollutants from construction sites has the potential of significantly exceeding a performance standard of 85 percent reduction typically required by local authorities. In fact, the stringent requirement of equaling pre- and post-development pollutant loading is highly achievable by the treatment train approach. The significant contribution from the integration of the SHARP model to the treatment train is that real-time assessment of pollutant loading reduction by volume can be planned and controlled to achieve target performance standards.
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Date Issued: 2012
Identifier: CFE0004539, ucf:49244
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004539

Title: Conservation and population biology: genetics, demography and habitat requirements of the Atlantic coast beach mice.
Creator: Kalkvik, Haakon, Parkinson, Christopher, Stout, I, Hoffman, Eric, Weishampel, John, Doonan, Terry, University of Central Florida
Abstract / Description: The conservation biology field seeks to preserve biodiversity and the processes shaping that variation. Conservation biology is intimately tied to evolutionary research, in order to identify evolutionary distinct lineages that may be in danger of disappearing. Interestingly, patterns and processes of lineage divergence and persistence change with respect to spatial and temporal scale. I seek to evaluate biodiversity, the factors that have shaped this heterogeneity, and how this variability...
Show moreThe conservation biology field seeks to preserve biodiversity and the processes shaping that variation. Conservation biology is intimately tied to evolutionary research, in order to identify evolutionary distinct lineages that may be in danger of disappearing. Interestingly, patterns and processes of lineage divergence and persistence change with respect to spatial and temporal scale. I seek to evaluate biodiversity, the factors that have shaped this heterogeneity, and how this variability persists. To accomplish this I used a phylogeographic approach as well as niche and population modeling on the Peromyscus maniculatus species group found widely distributed in North America. My emphasis was on the southeastern U.S. species P. polionotus and its distinct beach forms. At a continental scale, I found that environmental niches are likely involved in generating and/or maintaining genetic lineages within the P. maniculatus species group. These findings add to a growing number of studies that have identified lineages occupying different environmental spaces. At a regional scale, I supported the hypothesis that barrier islands on the Atlantic coast of Florida were colonized by an ancestral form of P. polionotus by a single colonization, from the central Florida area. Subsequently, at least two distinct lineages diverged (P. p. phasma and P. p. niveiventris). I also found evidence that suggests that the extinct form of beach mouse (P. p. decoloratus) is part of the P. p. phasma lineage. At the population level, I evaluated changes in genetic diversity in historical samples compared to those that experienced recent human encroachment on natural habitat I used tissue preserved in natural history collections to compare with live-trapped specimens, and found that P. p. niveiventris has maintained historical genetic diversity levels. I suggest that the continuation of historical levels of genetic diversity is due to the presence of a single large area of continuous habitat in the central portion of the species' current distribution. Finally, I evaluated the importance of scrub and beach habitat to the population dynamics of beach mice. Beach mice have traditionally have been associated with beach dunes rather than with the scrub habitat found more inland on barrier islands. Using almost three years of capture-recapture data from Cape Canaveral Air Force Station (CCAFS), I created a stochastic matrix model to assess the relative contribution of populations from the two different habitats to a variety of demographic measures. Both field data and model results provided evidence that the population dynamics of beach mice may rely much more on scrub habitat than formerly documented. Overall, my research emphasized a hierarchical approach to evaluate biodiversity and the processes shaping differentiation at different spatial and temporal scales. The methods and findings give insight into speciation at different scales, and can be applied to a wide range of taxa for questions related to evolutionary and conservation biology.
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Date Issued: 2012
Identifier: CFE0004392, ucf:49372
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004392

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: Determining the impacts of beach restoration on loggerhead (Caretta caretta) and green turtle (Chelonia mydas) nesting patterns and reproductive success along Florida's Atlantic coast.
Creator: Hays, Allison, Weishampel, John, Ehrhart, Llewellyn, Mota, Mario, Hinkle, Charles, University of Central Florida
Abstract / Description: Artificial beach nourishment, the most common method to mitigate coastal erosion in the United States, is also considered the most ecologically friendly alternative for shoreline stabilization. However, this habitat alteration has the potential to impact nesting marine turtles and developing hatchlings. The first objective of this study was to determine how nourishing beaches with two different design templates affects loggerhead (Caretta caretta) and green turtle (Chelonia mydas) nesting...
Show moreArtificial beach nourishment, the most common method to mitigate coastal erosion in the United States, is also considered the most ecologically friendly alternative for shoreline stabilization. However, this habitat alteration has the potential to impact nesting marine turtles and developing hatchlings. The first objective of this study was to determine how nourishing beaches with two different design templates affects loggerhead (Caretta caretta) and green turtle (Chelonia mydas) nesting success, the ratio of nests to the total number of nests and non-nesting emergences, and reproductive success, the ratio of hatched and emerged hatchlings to the total number of eggs deposited. Two types of restoration designs exist along the southern Brevard County, FL coastline, which supports some of the highest density loggerhead and green turtle nesting worldwide. Since 2005, approximately 35 kilometers of beach have undergone 1) full-scale restoration (typically called nourishment), where sand was added above and below the mean high tide line (2005, 2010) or 2) dune restoration, where sand was placed on the dune (2005, 2006, 2008, 2009). To quantify the effects of these restoration types, we used a Before-After-Control-Impact-Paired Series (BACIPS) model, which tests for significance between the difference in nesting success rates at the impact (engineered) and control sites (natural beach) before and after restoration (?). For loggerheads, there was a significant difference in ? after dune restoration during the years of construction (2005, 2006, 2008, and 2009; p(<)0.001) and one year post-construction (2007; p(<)0.05 and 2010; p(<)0.001). After full-scale restoration, there was a significant difference in ? during the years of construction (2005 and 2010; p (<)0.001) and one year post-construction (2006; p(<)0.001). For green turtles, there was a significant difference in ? after dune restoration during two of the four years of construction (2006; p(<)0.05 and 2008; p(<)0.01) and one of the two one-year post-construction years (2010; p(<)0.05). After full-scale restoration, the significant difference in ? lasted every season (2005-2010; p(<)0.001). There were no significant differences in ? for loggerhead or green turtle reproductive success rates after either type of restoration. The second objective was to use the different restoration designs to study what beach characteristics function as loggerhead nesting cues to explain why altering the beach decreases nesting success rates. We examined beach elevation and slope, sand moisture content, sand grain size, beach width, and distance traveled. Logistic regression model selection found all variables were important (R2=0.75). Further examination of trends, with each crawl divided into quarters, found beach slope served as a nesting cue. In all study sites except one, when turtles false crawled, the beach flattened out in the final quarter of the crawl. Conversely, in nesting emergences, the final quarter rose at a steeper slope than the previous quarter. Additionally, model selection found variables important in nest site selection were also important in hatching (R2=0.44) and emergence (R2=0.45) success. These results offer new insight into how and why marine turtle nesting patterns change after artificial nourishment, providing information necessary to nourish beaches in a more (")turtle-friendly(") manner. ?
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Date Issued: 2012
Identifier: CFE0004332, ucf:49447
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004332

Title: Incorporating Remotely Sensed Data into Coastal Hydrodynamic Models: Parameterization of Surface Roughness and Spatio-Temporal Validation of Inundation Area.
Creator: Medeiros, Stephen, Hagen, Scott, Weishampel, John, Wang, Dingbao, Yeh, Gour-Tsyh, University of Central Florida
Abstract / Description: This dissertation investigates the use of remotely sensed data in coastal tide and inundation models, specifically how these data could be more effectively integrated into model construction and performance assessment techniques. It includes a review of numerical wetting and drying algorithms, a method for constructing a seamless digital terrain model including the handling of tidal datums, an investigation into the accuracy of land use / land cover (LULC) based surface roughness...
Show moreThis dissertation investigates the use of remotely sensed data in coastal tide and inundation models, specifically how these data could be more effectively integrated into model construction and performance assessment techniques. It includes a review of numerical wetting and drying algorithms, a method for constructing a seamless digital terrain model including the handling of tidal datums, an investigation into the accuracy of land use / land cover (LULC) based surface roughness parameterization schemes, an application of a cutting edge remotely sensed inundation detection method to assess the performance of a tidal model, and a preliminary investigation into using 3-dimensional airborne laser scanning data to parameterize surface roughness.A thorough academic review of wetting and drying algorithms employed by contemporary numerical tidal models was conducted. Since nearly all population centers and valuable property are located in the overland regions of the model domain, the coastal models must adequately describe the inundation physics here. This is accomplished by techniques that generally fall into four categories: Thin film, Element removal, Depth extrapolation, and Negative depth. While nearly all wetting and drying algorithms can be classified as one of the four types, each model is distinct and unique in its actual implementation.The use of spatial elevation data is essential to accurate coastal modeling. Remotely sensed LiDAR is the standard data source for constructing topographic digital terrain models (DTM). Hydrographic soundings provide bathymetric elevation information. These data are combined to form a seamless topobathy surface that is the foundation for distributed coastal models. A three-point inverse distance weighting method was developed in order to account for the spatial variability of bathymetry data referenced to tidal datums. This method was applied to the Tampa Bay region of Florida in order to produce a seamless topobathy DTM.Remotely sensed data also contribute to the parameterization of surface roughness. It is used to develop land use / land cover (LULC) data that is in turn used to specify spatially distributed bottom friction and aerodynamic roughness parameters across the model domain. However, these parameters are continuous variables that are a function of the size, shape and density of the terrain and above-ground obstacles. By using LULC data, much of the variation specific to local areas is generalized due to the categorical nature of the data. This was tested by comparing surface roughness parameters computed based on field measurements to those assigned by LULC data at 24 sites across Florida. Using a t-test to quantify the comparison, it was proven that the parameterizations are significantly different. Taking the field measured parameters as ground truth, it is evident that parameterizing surface roughness based on LULC data is deficient.In addition to providing input parameters, remotely sensed data can also be used to assess the performance of coastal models. Traditional methods of model performance testing include harmonic resynthesis of tidal constituents, water level time series analysis, and comparison to measured high water marks. A new performance assessment that measures a model's ability to predict the extent of inundation was applied to a northern Gulf of Mexico tidal model. The new method, termed the synergetic method, is based on detecting inundation area at specific points in time using satellite imagery. This detected inundation area is compared to that predicted by a time-synchronized tidal model to assess the performance of model in this respect. It was shown that the synergetic method produces performance metrics that corroborate the results of traditional methods and is useful in assessing the performance of tidal and storm surge models. It was also shown that the subject tidal model is capable of correctly classifying pixels as wet or dry on over 85% of the sample areas.Lastly, since it has been shown that parameterizing surface roughness using LULC data is deficient, progress toward a new parameterization scheme based on 3-dimensional LiDAR point cloud data is presented. By computing statistics for the entire point cloud along with the implementation of moving window and polynomial fit approaches, empirical relationships were determined that allow the point cloud to estimate surface roughness parameters. A multi-variate regression approach was chosen to investigate the relationship(s) between the predictor variables (LiDAR statistics) and the response variables (surface roughness parameters). It was shown that the empirical fit is weak when comparing the surface roughness parameters to the LiDAR data. The fit was improved by comparing the LiDAR to the more directly measured source terms of the equations used to compute the surface roughness parameters. Future work will involve using these empirical relationships to parameterize a model in the northern Gulf of Mexico and comparing the hydrodynamic results to those of the same model parameterized using contemporary methods. In conclusion, through the work presented herein, it was demonstrated that incorporating remotely sensed data into coastal models provides many benefits including more accurate topobathy descriptions, the potential to provide more accurate surface roughness parameterizations, and more insightful performance assessments. All of these conclusions were achieved using data that is readily available to the scientific community and, with the exception of the Synthetic Aperture Radar (SAR) from the Radarsat-1 project used in the inundation detection method, are available free of charge. Airborne LiDAR data are extremely rich sources of information about the terrain that can be exploited in the context of coastal modeling. The data can be used to construct digital terrain models (DTMs), assist in the analysis of satellite remote sensing data, and describe the roughness of the landscape thereby maximizing the cost effectiveness of the data acquisition.
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Date Issued: 2012
Identifier: CFE0004271, ucf:49506
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004271

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: A SOCIO-ECONOMIC ASSESSMENT OF MARINE TURTLE ECO-TOURISM.
Creator: Cope, Kendra, Mansfield, Kate, Weishampel, John, Slotkin, Michael, DeFreese, Duane, University of Central Florida
Abstract / Description: Marine turtles have historically contributed to economic activity through consumptive harvest for food, tools, and decorative objects. Only recently have they begun to benefit humans economically through non-consumptive roles, primarily as a focal point of educational eco-tourism. In recent years, the annual number of turtle walks conducted around the Archie Carr National Wildlife Refuge (ACNWR) has risen. This expansion contributed to a statistically significant increase in attendance from 2...
Show moreMarine turtles have historically contributed to economic activity through consumptive harvest for food, tools, and decorative objects. Only recently have they begun to benefit humans economically through non-consumptive roles, primarily as a focal point of educational eco-tourism. In recent years, the annual number of turtle walks conducted around the Archie Carr National Wildlife Refuge (ACNWR) has risen. This expansion contributed to a statistically significant increase in attendance from 2,162 in 2001 to 3,047 participants in 2014. I examined the regional economic impacts of marine turtle eco-tourism around the ACNWR using social surveys and an economic impact analysis tool. IMPLAN, an input-output modeling package, has been used in tourism industries around the U.S. since 1992, but this study is the first to use this tool to evaluate the holistic economic effects of marine turtle-based eco-tourism within a selected region. During the 2014 turtle walk season (June through July), surveys were distributed at six different turtle walk locations within Brevard and Indian River Counties, Florida, along the central Florida Atlantic coast. Adults attending the turtle walks (n=2,274) were given time before the educational presentation began to complete a one-page survey. Approximately 93% of turtle walk participants completed surveys. Due to market interactions within this two-county region, turtle walks contributed a minimum of three new jobs and a conservative estimate of almost $250,000 (USD) to the local economy during the two-month turtle walk season. Using financial comparisons and economic impact tools, like IMPLAN, can improve our understanding of the many roles, especially non-consumptive uses, sea turtles have in our communities. This information can be useful in resource management and conservation-based decision making.
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Date Issued: 2015
Identifier: CFE0005934, ucf:50845
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005934

Title: Hydrologic controls on the natural drainage networks extracted from high-resolution topographic data.
Creator: Hooshyar, Milad, Wang, Dingbao, Medeiros, Stephen, Singh, Arvind, Kibler, Kelly, Weishampel, John, University of Central Florida
Abstract / Description: Drainage networks are important geomorphologic and hydrologic features which significantly control runoff generation. Drainage networks are composed of unchannelized valleys and channels. At valley heads, flow changes from unconfined sheet flow on the hillslope to confined flow in valley. Localized confined flow dominates in valleys as a result of convergent topography with positive curvature. Channels initiate at some distance down from the valley head, and the transition from unchannelized...
Show moreDrainage networks are important geomorphologic and hydrologic features which significantly control runoff generation. Drainage networks are composed of unchannelized valleys and channels. At valley heads, flow changes from unconfined sheet flow on the hillslope to confined flow in valley. Localized confined flow dominates in valleys as a result of convergent topography with positive curvature. Channels initiate at some distance down from the valley head, and the transition from unchannelized valley to channel is referred to as the channel head. Channel heads occur at a point where fluvial transport dominates over diffusive transport.From the hydrologic perspective, channels are categorized as perennial, intermittent, and ephemeral streams based on the flow durations. Perennial streams flow for the most of the time during normal years and are maintained by groundwater discharge. Intermittent (i.e. seasonal) streams flow during certain times of the year receiving water from surface sources such as melting snow or from groundwater. Lastly, ephemeral streams flow only in direct response to precipitation without continuous surface flow. In this dissertation, the hydrologic controls on the drainage networks extracted from high resolution Digital Elevation Models (DEMs) based on Light Detection and Ranging (LiDAR) are investigated. A method for automatic extraction of valley and channel networks from high-resolution DEMs is presented. This method utilizes both positive (i.e., convergent topography) and negative (i.e., divergent topography) curvature to delineate the valley network. The valley and ridge skeletons are extracted using the pixels' curvature and the local terrain conditions. The valley network is generated by checking the terrain for the existence of at least one ridge between two intersecting valleys. The transition from unchannelized to channelized sections (i.e., channel head) in each 1st-order valley tributary is identified independently by categorizing the corresponding contours using an unsupervised approach based on K-means clustering. The method does not require a spatially constant channel initiation threshold (e.g., curvature or contributing area). Moreover, instead of a point attribute (e.g., curvature), the proposed clustering method utilizes the shape of contours, which reflects the entire cross-sectional profile including possible banks. The method was applied to three catchments: Indian Creek and Mid Bailey Run in Ohio, and Feather River in California. The accuracy of channel head extraction from the proposed method is comparable to state-of-the-art channel extraction methods. Valleys extracted from DEMs may be wet (flowing) or dry at any given time depending on the hydrologic conditions. The temporal dynamics of flowing streams are vitally important for understanding hydrologic processes including surface water and groundwater interaction and hydrograph recession. However, observations of wet channel networks are limited, especially in headwater catchments. Near infrared LiDAR data provide an opportunity to map wet channel networks owing to the fine spatial resolution and strong absorption of light energy by water surfaces. A systematic method is developed to map wet channel networks by integrating elevation and signal intensity of ground returns. The signal intensity thresholds for identifying wet pixels are extracted from frequency distributions of intensity return within the convergent topography extent using a Gaussian mixture model. Moreover, the concept of edge in digital image processing, defined based on the intensity gradient, is utilized to enhance detection of small wet channels. The developed method was applied to the Lake Tahoe area based on eight LiDAR acquisitions during recession periods in five watersheds. A power-law relationship between streamflow and wetted channel length during recession periods was derived, and the scaling exponent (L?Q^0.38) is within the range of reported values from fieldwork in other regions.Several studies in the past focused on the relationship between drainage density (i.e., drainage length divided by drainage area) and long-term climate and reported a U-shape pattern. In this dissertation, this relationship was re-visited and the effect of drainage area on drainage density was investigated. Long-term climate was quantified by climate aridity indices which is the ratio between long-term potential evaporation and precipitation. 120 study sites across the United States with minimal human disturbance and a wide range of climate aridity index were selected based on the availability of LiDAR data. The drainage networks were delineated from LiDAR-based 1 m DEMs using the proposed curvature-based method. Despite the U-shaped relationship in the literature, our result shows a significant decreasing trend in the drainage density versus climate aridity index in arid regions; whereas no trend is observed in humid watersheds. This observation and its discrepancy with the reported pattern in the literature are justified considering the dynamics of the runoff erosive force and the resistance of vegetation and the climate controls on them. Our findings suggest that natural drainage networks in arid regions are more sensitive to the change in long-term climate conditions compared with drainage networks in humid climate. It was also found that drainage density has a decreasing trend with drainage area in arid regions; however, no trend was observed in humid regions. In a broader sense, the findings influence our understanding of the formation of drainage networks and the response of hydrologic systems to climate change. The formation and growth of river channels and their network evolution are governed by the erosional and depositional processes operating on the landscape due to movement of water. The branching angles, i.e., the angle between two adjoining channels, in drainage networks are important features related to the network topology and contain valuable information about the forming mechanisms of the landscape. Based on channel networks extracted from 1 m Digital Elevation Models of 120 catchments with minimal human impacts across the United States, we showed that the junction angles have two distinct modes with ?1 ? 49.5(&)deg; and ?2 ? 75.0(&)deg;. The observed angles are physically explained as the optimal angles that result in minimum energy dissipation and are linked to the exponent characterizing slope-area curve. Our findings suggest that the flow regimes, debris-flow dominated or fluvial, have distinct characteristic angles which are functions of the scaling exponent of the slope-area curve. These findings enable us to understand the geomorphologic signature of hydrologic processes on drainage networks and develop more refined landscape evolution models.
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Date Issued: 2017
Identifier: CFE0006604, ucf:51278
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006604

Title: An Integrated Hydrodynamic-Marsh Model with Applications in Fluvial, Marine, and Mixed Estuarine Systems.
Creator: Alizad, Karim, Hagen, Scott, Medeiros, Stephen, Wang, Dingbao, Weishampel, John, University of Central Florida
Abstract / Description: Coastal wetlands experience fluctuating productivity when subjected to various stressors. One of the most impactful stressors is sea level rise (SLR) associated with global warming. Research has shown that under SLR, salt marshes may not have time to establish an equilibrium with sea level and may migrate landward or become open water. Salt marsh systems play an important role in the coastal ecosystem by providing intertidal habitats and food for birds, fish, crabs, mussels, and other animals...
Show moreCoastal wetlands experience fluctuating productivity when subjected to various stressors. One of the most impactful stressors is sea level rise (SLR) associated with global warming. Research has shown that under SLR, salt marshes may not have time to establish an equilibrium with sea level and may migrate landward or become open water. Salt marsh systems play an important role in the coastal ecosystem by providing intertidal habitats and food for birds, fish, crabs, mussels, and other animals. They also protect shorelines by dissipating flow and damping wave energy through an increase in drag forces. Due to the serious consequences of losing coastal wetlands, evaluating the potential future changes in their structure and distribution is necessary in order for coastal resource managers to make informed decisions. The objective of this study was to develop a spatially-explicit model by connecting a hydrodynamic model and a parametric marsh model and using it to assess the dynamic effects of SLR on salt marsh systems within three National Estuarine Research Reserves (NERRs) in the Northern Gulf of Mexico. Coastal salt marsh systems are an excellent example of complex interrelations between physics and biology, and the resulting benefits to humanity. In order to investigate salt marsh productivity under projected SLR scenarios, a depth integrated hydrodynamic model was coupled to a parametric marsh model to capture the dynamic feedback loop between physics and biology. The hydrodynamic model calculates mean high water (MHW) and mean low water (MLW) within the river and tidal creeks by harmonic analysis of computed tidal constituents. The responses of MHW and MLW to SLR are nonlinear due to localized changes in the salt marsh platform elevation and biomass productivity (which influences bottom friction). Spatially-varying MHW and MLW are utilized in a two-dimensional application of the parametric Marsh Equilibrium Model to capture the effects of the hydrodynamics on biomass productivity and salt marsh accretion, where accretion rates are dependent on the spatial distribution of sediment deposition in the marsh. This model accounts both organic (decomposition of in-situ biomass) and inorganic (allochthonous) marsh platform accretion and the effects of spatial and temporal biomass density changes on tidal flows. The coupled hydro-marsh model, herein referred to as HYDRO-MEM, leverages an optimized coupling time step at which the two models exchange information and update the solution to capture the system's response to projected linear and non-linear SLR rates.Including accurate marsh table elevations into the model is crucial to obtain meaningful biomass productivity projections. A lidar-derived Digital Elevation Model (DEM) was corrected by incorporating Real Time Kinematic (RTK) surveying elevation data. Additionally, salt marshes continually adapt in an effort to reach an equilibrium within the ideal range of relative SLR and depth of inundation. The inputs to the model, specifically topography and bottom roughness coefficient, are updated using the biomass productivity results at each coupling time step to capture the interaction between the marsh and hydrodynamic models.The coupled model was tested and validated in the Timucuan marsh system, located in northeastern Florida by computing projected biomass productivity and marsh platform elevation under two SLR scenarios. The HYDRO-MEM model coupling protocol was assessed using a sensitivity study of the influence of coupling time step on the biomass productivity results with a comparison to results generated using the MEM approach only. Subsequently, the dynamic effects of SLR were investigated on salt marsh productivity within the three National Estuarine Research Reserves (NERRs) (Apalachicola, FL, Grand Bay, MS, and Weeks Bay, AL) in the Northern Gulf of Mexico (NGOM). These three NERRS are fluvial, marine and mixed estuarine systems, respectively. Each NERR has its own unique characteristics that influence the salt marsh ecosystems. The HYDRO-MEM model was used to assess the effects of four projections of low (0.2 m), intermediate-low (0.5 m), intermediate-high (1.2 m) and high (2.0 m) SLR on salt marsh productivity for the year 2100 for the fluvial dominated Apalachicola estuary, the marine dominated Grand Bay estuary, and the mixed Weeks Bay estuary. The results showed increased productivity under the low SLR scenario and decreased productivity under the intermediate-low, intermediate-high, and high SLR. In the intermediate-high and high SLR scenarios, most of the salt marshes drowned (converted to open water) or migrated to higher topography. These research presented herein advanced the spatial modeling and understanding of dynamic SLR effects on coastal wetland vulnerability. This tool can be used in any estuarine system to project salt marsh productivity and accretion under sea level change scenarios to better predict possible responses to projected SLR scenarios. The findings are not only beneficial to the scientific community, but also are useful to restoration, planning, and monitoring activities in the NERRs. Finally, the research outcomes can help policy makers and coastal managers to choose suitable approaches to meet the specific needs and address the vulnerabilities of these three estuaries, as well as other wetland systems in the NGOM and marsh systems anywhere in the world.
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Date Issued: 2016
Identifier: CFE0006523, ucf:51360
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006523

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: Modeling Survival of Immature Loggerheads (Caretta caretta) and Green Turtles (Chelonia mydas) from 10 Years of Mark-Recapture Data at the Florida Power and Light St. Lucie Plant.
Creator: Sterner, Andrew, Weishampel, John, Ehrhart, Llewellyn, Walters, Linda, Breininger, David, University of Central Florida
Abstract / Description: Loggerheads (Caretta caretta) are listed as Threatened and green turtles (Chelonia mydas) are listed as Endangered under the United States Endangered Species Act. While green turtle nest production in Florida has increased markedly in recent years, loggerhead nest production has followed a more tenuous path. Reasons for these differences are unknown. Limited demographic information is available for these species of conservation concern. I used Barker models, which incorporated mark-recapture,...
Show moreLoggerheads (Caretta caretta) are listed as Threatened and green turtles (Chelonia mydas) are listed as Endangered under the United States Endangered Species Act. While green turtle nest production in Florida has increased markedly in recent years, loggerhead nest production has followed a more tenuous path. Reasons for these differences are unknown. Limited demographic information is available for these species of conservation concern. I used Barker models, which incorporated mark-recapture, live-resight and dead recovery data, implemented in Program MARK. These models were used to estimate apparent survival for immature loggerhead ((<)85cm SCL) and green turtle ((<)60cm SCL) populations foraging in the Atlantic Ocean adjacent to the Florida Power and Light St. Lucie Plant on Hutchinson Island, Florida between 2002 and 2011. My results indicated annual apparent survival was decreasing (from 0.75 to 0.59) for resident immature loggerheads and was stable (~0.81) for resident immature green turtles over the ten year study period. I found that permanent emigration models were better supported than no movement models for both species. Size (straight carapace length) was found to be an important covariate for survival and fidelity parameters in the green turtle analysis but not in the loggerhead analysis. My study is the first to compare survival of two species of immature marine turtles foraging at the same location in the Atlantic. These estimates are also the first available survival estimates for immature marine turtle populations in Florida based on modern mark-recapture techniques, filling a critical knowledge gap. This information is vitally important for managers when evaluating the long-term recovery of these endangered species.
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Date Issued: 2013
Identifier: CFE0004755, ucf:49770
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004755

Title: Sex ratios of juvenile green turtles (Chelonia mydas) in three developmental habitats along the east coast of Florida.
Creator: Sanchez, Cheryl, Weishampel, John, Ehrhart, Llewellyn, VonHolle, Mary, Wibbels, Thane, University of Central Florida
Abstract / Description: The concept of temperature dependent sex determination (TSD) has been somewhat of anevolutionary enigma for many decades and has had increased attention with the growingpredictions of a changing climate, particularly in species that are already threatened or endangered. TSD taxa of concern include marine turtles, which go through various life stages covering a range of regions. This, in turn, creates difficulties in addressing basic demographic questions. Secondary sex ratios (from life...
Show moreThe concept of temperature dependent sex determination (TSD) has been somewhat of anevolutionary enigma for many decades and has had increased attention with the growingpredictions of a changing climate, particularly in species that are already threatened or endangered. TSD taxa of concern include marine turtles, which go through various life stages covering a range of regions. This, in turn, creates difficulties in addressing basic demographic questions. Secondary sex ratios (from life stages post-hatchling) were investigated by capturing juvenile green turtles (Chelonia mydas), 22.6-60.9 cm in straight carapace length (SCL), from three developmental areas along the east coast of Florida (a region known to have important juvenile aggregations) by analyzing circulating testosterone levels. All three aggregations exhibited significant female biases with an overall ratio of 3.2:1 (female: male). The probability of a turtle being female increased as the size of the individual decreased. Ratios obtained in this study were slightly less female-biased, but not significantly different, than those observed in the late 1990s. However, they were significantly more biased than those found in a late 1980s pilot study. The shift to significantly female-biased ratios may be beneficial to a recovering population, an evolutionary adaptation, and is common among juvenile aggregations. A more skewed female bias in smaller size classes may be indicative of recent, warmer periods during incubation on the nesting beaches. This female bias could become more exaggerated if temperatures meet future climate warming predictions.
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Date Issued: 2013
Identifier: CFE0004747, ucf:49771
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004747

Title: Landscaping Perceptions and Behaviors: Socio-ecological Drivers of Nitrogen in the Residential Landscape.
Creator: Souto, Leesa, Hinkle, Charles, Canan, Penelope, Noss, Reed, Weishampel, John, Pals, Heili, University of Central Florida
Abstract / Description: Driven by individual influences such as beliefs, attitudes, personal norms, and abilities, as well as by social influences like community norms, mandates, and the market, suburban homeowners are motivated to select and maintain a turf grass landscape. In many areas of Florida, effective suburban lawn maintenance requires regular inputs of nitrogenous fertilizer, some of which is lost to the environment, contributing to water quality degradation and ecosystem dysfunction. Reducing nitrogen...
Show moreDriven by individual influences such as beliefs, attitudes, personal norms, and abilities, as well as by social influences like community norms, mandates, and the market, suburban homeowners are motivated to select and maintain a turf grass landscape. In many areas of Florida, effective suburban lawn maintenance requires regular inputs of nitrogenous fertilizer, some of which is lost to the environment, contributing to water quality degradation and ecosystem dysfunction. Reducing nitrogen inputs to aquatic systems requires a better understanding of the links between residential landscape management and the potential for fertilizer loss. This dissertation examines the linkages between the human behaviors contributing nitrogen to the suburban landscape and the resulting environmental impacts. Framed in socio-psychological theory and social marketing research, the outcomes of this dissertation contribute much needed information to the growing realm of interdisciplinary science that expands integrative theory, develops mixed methods, utilizes spatial and temporal analyses, and conducts actionable research.
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Date Issued: 2012
Identifier: CFE0004604, ucf:49931
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004604

Title: A Sustainability "Green" Certification Audit of Food Service Operations and the Development of a Restaurant Sustainability Instrument.
Creator: Hagglund, Hans, Tesone, Dana, Rompf, Paul, Robinson, Edward, Fjelstul, Jill, Weishampel, John, University of Central Florida
Abstract / Description: This study investigates current green restaurants certifications as well as developing a new more user friendly certification. First, a fact finding investigation to find the most established and commonly utilized green restaurant certifications. Second, a new green certification was developed. Third, chosen green restaruant certifications were compared. Last, the new green certification analyzed wether restaurants in the central Florida area utilized green practices.
Date Issued: 2013
Identifier: CFE0004687, ucf:49878
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004687

LiDAR (5)	+ -
Florida (3)	+ -
remote sensing (3)	+ -
sea level rise (3)	+ -
Gulf of Mexico (2)	+ -

biology (2)	+ -
climate change (2)	+ -
connectivity (2)	+ -
ecology (2)	+ -
fire (2)	+ -
habitat preference (2)	+ -
habitat selection (2)	+ -
landscape ecology (2)	+ -
lidar (2)	+ -
mangroves (2)	+ -
nitrogen (2)	+ -
3-D structure (1)	+ -
ADCIRC (1)	+ -
Ancient Agriculture (1)	+ -
Apalachicola (1)	+ -
Apalachicola National Estuarine Research Reserve (1)	+ -
Archie Carr National Wildlife Refuge (1)	+ -
Barker Models (1)	+ -
Beach Erosion (1)	+ -
Beach Restoration (1)	+ -
Benthic Macroinvertebrate (1)	+ -
Bioassessments (1)	+ -
Biology (1)	+ -
Bottlenose dolphin (1)	+ -
Brazilian pepper (1)	+ -

University of Central Florida (43)	+ -
Weishampel, John (41)	+ -
Quintana-Ascencio, Pedro (7)	+ -
VonHolle, Mary (6)	+ -
Walters, Linda (6)	+ -

Wang, Dingbao (6)	+ -
Ehrhart, Llewellyn (5)	+ -
Hagen, Scott (5)	+ -
Hinkle, Charles (4)	+ -
Hoffman, Eric (4)	+ -
Medeiros, Stephen (4)	+ -
Noss, Reed (4)	+ -
Weishampel, John F. (2)	+ -
Worthy, Graham (2)	+ -
Albarracín, María (1)	+ -
Alizad, Karim (1)	+ -
Alvarez, Camila (1)	+ -
Angelo, James (1)	+ -
Bowdon, Melody (1)	+ -
Breininger, David (1)	+ -
Brenckle, Martha (1)	+ -
Brody, Samuel (1)	+ -
Butterfield, Anna (1)	+ -
Canan, Penelope (1)	+ -
Castro, Joshua (1)	+ -
Ceriani, Simona (1)	+ -
Chase, Arlen (1)	+ -
Chopra, Manoj (1)	+ -
Cope, Kendra (1)	+ -
DeFreese, Duane (1)	+ -

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