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Identifying mating systems of imperiled marine turtles nesting in southern Florida through exclusion analysis to estimate the breeding sex ratioUnknown Date (has links)
The reproductive behavior of migratory organisms is difficult to characterize as
the mating behavior can be difficult to observe. For some species, one sex can be readily
observable, but the other may remain hidden, confounding attempts to assess population
demographics. For such species, it can be difficult to determine the sex ratio of the
population. Without accurate accounts of the numbers of males and females, conservation
methods may be insufficient and their performance unclear. Alternative methods of
measuring sex ratios therefore must be used to estimate the number of individuals and
assess breeding behavior. Here I identified breeding sex ratios (BSR) measured using
paternity analysis of offspring through exclusion analysis to quantify the numbers of
males contributing. Here I discuss the mating behavior of three species of marine turtle
that nest in southern Florida: the loggerhead (Caretta caretta), the leatherback (Dermochelys coriacea), and the green sea turtle (Chelonia mydas) at three beaches
(Boca Raton, Juno Beach, and Sanibel Island) from 2013-2017; over 400 nesting females
were identified and genotyped and almost 7,000 hatchlings were collected and
genotyped. Females from all three species successfully mated with more than one male in
all years analyzed demonstrating multiple paternity of clutches. For loggerheads, many
male genotypes were identified, suggesting that females likely mate en route to their
nesting grounds, inducing a male-biased BSR. Examination of females that were sampled
more than once per season (repeats), evidence of sperm storage was found for all nests
and some turtles might mate in between nesting events. Leatherback females displayed a
higher rate of multiple paternity than was previously published for other Caribbean
nesting sites; I hypothesize that this result may be due to a mainland nesting beach effect.
The leatherback BSR over all years was approximately 1:1, and one male was identified
fathering than two different females’ nests (polygyny). For green turtles, multiple
paternity was found and there was evidence of polygyny. Across all three species,
evidence for indirect benefits of mating multiply (hatching success or larger hatchlings)
was weak or not supported. Together, the four studies contribute to the overall body of
reproductive behavior studies. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection
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Comparison and differentiation in fossil and recent specimens of the melongenid subgenus Rexmela in FloridaUnknown Date (has links)
The subgenus Rexmela, located primarily in Florida, is newly evolved, dating back 1.6 million years, first occurring in the Ayer's Landing Member of the Caloosahatchee Formation. This subgenus has highly variably shell morphology and has led to the erection of several species and subspecies. In order to provide a quantitative methodology with which to differentiate between populations, samples of Recent and fossil populations were collected and measured for a variety of parameters. The parameters measured included length, width, spire height, and several angles, and allowed for a discriminate analysis to be completed. The analysis supported the distinction of several of the populations as ecophenotypes. Paleoenvironments of the fossil populations were then recreated using analogues of Recent populations. / by Crystal Pletka. / Thesis (M.S.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.
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Archaeomalacological Data and Paleoenvironmental Reconstruction at the Jupiter Inlet I Site (8PB34a), Southeast FloridaUnknown Date (has links)
The Jupiter Inlet I site is situated between the Atlantic coast and the Loxahatchee
River in southeast Florida. Although excavations were previously conducted, faunal
remains were not systematically collected until recently. Molluscan remains recovered in
2010 are examined to reconstruct past ecological habitats, identify which water bodies
were used for extracting resources, and document changes in molluscan species over
time. Based upon identifications, only brackish and marine species are represented,
indicating that the Loxahatchee River was brackish rather than freshwater during the time
of occupation and that the site inhabitants were collecting mollusks from both the lagoon
and coastal waters. / Includes bibliography. / Thesis (M.A.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection
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Distribution and Diversity of Benthic Foraminifera Within the Nearshore Ridge Complex off Pompano Beach, Broward County, Florida.Unknown Date (has links)
Benthic foraminifera are exceptional organisms with distinctive features that allow for interpretation of both past and present environmental conditions. Some benthic foraminifera are widely distributed while some are restricted to specific environments due to their way of life. Foraminiferal assemblages south of Biscayne Bay and north of Cape Canaveral have previously been investigated; however, a gap exists in data covering a transitional zone along the Florida coast between the tropical waters of the western Atlantic and the cooler coastal waters along the North American coast. The purpose of this study was to collect baseline data on the benthic foraminifera of the small marine environment off of Pompano Beach that falls within this zone. This environment has a very particular relict reef system that includes a near-shore ridge complex, the unique foraminiferal assemblage of which has not been documented. Thirteen rubble samples were collected from this near shore ridge complex between October 2013 and April 2015 from depths of 2.5m – 9m. Abundances and diversity indices were calculated, and multivariate analysis and SHEBI analysis carried out to summarize baseline data for the area. Substrate types and seasonal collections were compared with foraminiferal abundances to determine if benthic foraminifera diversity varied between the four substrate types found on the near-shore ridge and between wet and dry seasons in Florida. Results revealed a variation in abundances for both substrates and seasons with the dominant genera being Quinqueloculina, Laevipeneroplis, and Archaias. Multivariate analysis displayed dissimilarities between substrates colonized by corals and those that were uncolonized. Comparison of studies from surrounding areas revealed fewer, however similar, species and different dominant genera. Overall, this area has proven to be a different environment compared to surrounding coastal areas and merits further investigation. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection
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The Impact of Voluntary Remediation on Gateway Course Success and Minority and Low-Income Students in Florida CollegesUnknown Date (has links)
The primary purpose of the study was to explore the potential impact of voluntary remediation on success in ENC1101 and MAT1033 (gateway courses) and on minority or low-income students in Florida. The study was prompted in 2013 when the Florida Senate exempted most students entering the Florida College System from placement testing or developmental education regardless of their skill level. A quantitative design compared the gateway course success of 10,703 exempt students in 2014 and 2015 to the success of 8,644 students who would have been exempt had the law been in effect when they completed their gateway courses in 2012 and 2013. Data were collected from three FCS institutions. Using Astin and Astin's 1992 Input-Environment-Outcome model (Astin & Astin, 1992), independent variables included demographics, such as race and Pell grant eligibility, and prior academic performance, as well as enrollment status and remedial course decisions and perf ormance. The study found the policy to have a statistically significant (α = .05) negative effect on student success in the gateway courses. The voluntary remediation policy that was in part enacted to improve college completion rates threatens to have the opposite effect. The results show that fewer proportions of students were successful (grade of C or higher) in both courses once remediation became voluntary (12.8% decrease for English; 19.3% decrease in math). The study revealed a need for further research to investigate the degree of this impact on minority and low-income students. The results also suggested a need for more research to learn which students are likely to benefit, or not, by taking a remedial course. Of the students in the study who voluntarily took a placement test and scored below credit level, 11.3% chose remediation before taking ENC1101 and 24.5% chose remediation before taking MAT1033. Of those students, most who earned an A or B in the remedial course were successful in the credit courses; most who did not earn at least a B in the remedial course were unsuccessful at the credit level. Results were significant (α = .05), and effect sizes were moderate (.344 for English; .430 for math). / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection
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The effects of the Ready for Success program in the reading achievement of second- and third-grade studentsUnknown Date (has links)
The focus of this study is on evaluating the impact of a school counselor-led program, Ready for Success (RFS) on the academic achievement of second- and third grade students. The research question investigated in this study was: How do students in grades 2 and 3 who receive the RFS classroom intervention perform on the Scholastic Reading Inventory (SRI) when compared to students in grades 2 and 3 who do not receive the RFS classroom intervention. This study is significant because it addresses the need for more outcome research tying school counselor led interventions to student achievement. Research based interventions for school counselors that improve academic achievement directly address the current focus on student achievement outcomes as well as the need for accountability of school counselors. The sample for this study included 240 participants, 107 in the treatment group and 133 in the comparison group. Students were selected from all second- and third-grade classes at four schools in South Florida. There were 66 participants in the second grade; 37 were male and 29 were female. There were 174 participants in the third grade; 92 were male and 82 were female. Academic achievement was measured using a standardized, objective, state-wide assessment instrument, the Scholastic Reading Inventory (SRI). The analysis used for this study was an analysis of covariance (ANCOVA). Pretest scores on the SRI were used in the study as covariates on the dependent variable to account for group differences at pretest. The statistical analysis shows that there was no significant difference between the comparison and treatment group reading achievement levels on the SRI. Upon further review of the research a significant, confounding variable was discovered. High concentration of non-ESOL students were in the comparison group as compared to the treatment group. / Further data exploration led to a discovery of variance in the fidelity of treatment, which may have also accounted for the given results. The lack of a significant finding may suggest the need for elements of the program to be adjusted particularly when considering that the two programs upon which RFS was based have been consistently shown to be effective. / by Michelle L. Goldberg. / Thesis (Ph.D.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.
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Comparison of chemotaxonomic methods for the determination of periphyton community compositionUnknown Date (has links)
Pigment-based chemotaxonomy uses relative amounts of photosynthetic pigments (biomarkers) within algae samples to determine the algal class composition of each sample. Chemotaxonomy has been applied successfully to phytoplankton communities, but its efficacy for periphyton has not yet been established. This study examined the ability of simultaneous linear equations (SLE), CHEMTAX, and the Bayesian Compositional Estimator (BCE) to determine algal class composition in Florida Everglades periphyton. The methods were applied to artificial datasets, mixed lab cultures of known composition, and Everglades periphyton samples for which microscopic biovolume data was available. All methods were able to return accurate sample compositions for artificial data and mixed lab cultures. Correlation between pigment methods and microscopic results for natural periphyton samples was poor. SLE and CHEMTAX returned similar results for all samples while BCE performed less well. / by Jamie L. Browne. / Thesis (M.S.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.
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The effects of water depth and vegetation on wading bird foraging habitat selection and foraging succes in the EvergladesUnknown Date (has links)
Successful foraging by avian predators is influenced largely by prey availability. In a large-scale experiment at the Loxahatchee Impoundment Landscape Assessment project within the Arthur R. Marshall Loxahatchee National Wildlife Refuge, I manipulated two components of prey availability, water depth and vegetation density (submerged aquatic vegetation and emergent vegetation), and quantified the response by wading birds in terms of foraging habitat selection and foraging success. Manly's standardized selection index showed that birds preferred shallow water and intermediate vegetation densities. However, the treatments had little effect on either individual capture rate or efficiency. This was a consistent pattern seen across multiple experiments. Birds selected for certain habitat features but accrued little benefit in terms of foraging success. I hypothesize that birds selected sites with shallow water and intermediate vegetation densities because they anticipated higher prey densities, but they did not experience it here because I controlled for prey density. / by Samantha Lantz. / Thesis (M.S.)--Florida Atlantic University, 2008. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2008. Mode of access: World Wide Web.
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The avian community characteristics of constructed treatment wetlands of South FloridaUnknown Date (has links)
This study compared the avian communities of treatment wetlands in South Florida called Stormwater Treatment Wetlands (STAs) to those in natural marshes and crop lands, and examined factors that influenced the size and structure of the avian communities within the STAs. The STAs contained a more abundant, rich and distinct avian community compared to reference land types. The STAs were dominated by wintering waterfowl, and therefore community patterns fluctuated more seasonally other land types. Within the STAs, density and richness in the fall and winter were much greater in the submerged aquatic vegetation than in the mixed emergent vegetation when waterfowl were present. The STAs maintain two vegetation treatments which enhanced their biodiversity value by supporting distinct avian communities with different migratory strategies This suggests the increase in treatment wetlands could partially offset the loss of natural wetlands, but avian communities in treatment wetlands are not surrogates for natural wetlands. / by Tyler J. Beck. / Thesis (M.S.)--Florida Atlantic University, 2013. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
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Mangrove Morphological Change Across an Environmental Gradients: Implications for Competitive Ability in a Changing ClimateUnknown Date (has links)
In Florida, mangroves have responded to climate change by slowly migrating
northward into traditional salt marsh habitat. However, little is understood about the
relationships among mangrove growth form plasticity and environmental conditions. In
addition, the effects of the mangrove northward expansion on pre-existing salt marsh
communities are unknown, especially any influences of differences in tree morphology.
The size, canopy structure, and root structure of the three mangrove species Rhizophora
mangle, Avicennia germinans, and Laguncularia racemosa were measured at six sites
along the east coast of Florida. Structural equation modeling was used to evaluate the
multivariate relationships between environmental and biotic variables. Mangrove growth
form varied widely with environmental variables. The results of this study suggest that R.
mangle expansion into salt marsh may rely on interactions with salt marsh and shading as
well as on climatic variables, which has implications for future mangrove expansion
northward in Florida. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection
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