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<p> Four coral reef sites were observed in Spermonde Archipelago, off Southwest Sulawesi, Indonesia The sites were located at different distances from the mainland: Kayangan reef ('affected' site) is the closest and Samalona, Barang Lompo, and Kapoposan ('comparison' sites) are successively farther from the mainland and Ujung Pandang city. </p> <p> Coral cover, number of species at 3m and 1Om depths, and coral growth rates (Porites lobata) were observed to describe coral conditions. Environmental parameters suspended particulate matter (SPM), resuspended sediment, salinity, clarity, chlorophyll a, phosphate, nitrate, ammonium and o15N values ofcoral tissue (P. lobata) were also investigated to assess possible 'stress' factors on the reefs. </p> <p> Average coral cover at the 'affected' site was very low (14 %), compared to the other sites: Samalona (44.3 %), B. Lompo {47.2 %) and Kapoposan {66.6 %). Also, the lowest total number ofspecies occurred at Kayangan (42 spp.), compared to the other sites: Samalona {62 spp.), B. Lompo {71·spp.) and Kapoposan (80 spp.) </p> <p> Environmental parameters indicated that sedimentation and eutrophication (sewage) were the main 'stress' factors at Kayangan reef: while human disturbances such as fish bombing. anchoring. coral collection, and other activities affected Samalona and B. Lompo more. High coral cover and number of species at Kapoposan reef indicated fewer 'stress' factors. </p> <p> Coral growth rates showed a different trend from coral cover and total number of species. The highest coral growth rates occurred at B. Lompo (15.9 ± 0.8 mm yr-1) followed by Kayangan, Samalona and Kapoposan. Based on environmental parameters, it seemed that coral growth rates were higher at more eutrophic reefs, but slower at certain maximum critical nutrient values. </p> <p> δ^15 values of coral tissue found in this study are positively correlated with chlorophyll a, dissolved nutrients, and sedimentation rates. The high δ^(15)N values at Kayangan (8.03 ± 0.62 %) support the idea that this site was affected by human waste and sewage. </p> / Thesis / Master of Science (MSc)

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Chui, Pui Yi. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 133-149). / Abstracts in English and Chinese. / Abstract (English) --- p.i / Abstract (Chinese) --- p.v / Acknowledgements --- p.vii / Contents --- p.viii / List of Tables --- p.xi / List of Figures --- p.xii / Chapter Chapter 1 --- General Introduction and Thesis Outline --- p.1 / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.1.1 --- Coral reefs and conservation --- p.1 / Chapter 1.1.2 --- Reproduction in scleractinian corals --- p.3 / Chapter 1.1.2.1 --- Sexual reproductive pattern --- p.3 / Chapter 1.1.2.2 --- Overview of coral spawning patterns --- p.5 / Chapter 1.1.2.3 --- Environmental factors regulating coral reproduction --- p.7 / Chapter 1.1.3 --- Coral recruitment --- p.9 / Chapter 1.2 --- Coral Communities in Hong Kong --- p.12 / Chapter 1.3 --- Objectives --- p.13 / Chapter 1.4 --- Study Sites- Tung Ping Chau Marine Park --- p.14 / Chapter 1.5 --- Thesis outline --- p.15 / Chapter Chapter 2 --- "Spawning of Scleractinian Corals in Hong Kong, Larval Culture and Development" --- p.20 / Chapter 2.1 --- Introduction --- p.20 / Chapter 2.2 --- Methods and Materials --- p.22 / Chapter 2.2.1 --- Site description --- p.22 / Chapter 2.2.2 --- Spawning observation --- p.23 / Chapter 2.2.3 --- "Target coral species, Platygyra acuta" --- p.23 / Chapter 2.2.4 --- Coral gamete collection --- p.24 / Chapter 2.2.5 --- Fertilization and larval rearing --- p.26 / Chapter 2.2.6 --- Embryonic development of Platygyra acuta larvae --- p.28 / Chapter 2.2.7 --- Induced settlement of coral larvae --- p.29 / Chapter 2.2.8 --- Environmental cues that triggered the spawning events --- p.30 / Chapter 2.3 --- Results --- p.31 / Chapter 2.3.1 --- Spawning observation --- p.31 / Chapter 2.3.1.1 --- May 2009 --- p.32 / Chapter 2.3.1.2 --- May- Early June 2010 --- p.33 / Chapter 2.3.1.3 --- Late June 2010 --- p.36 / Chapter 2.3.1.4 --- July 2010 --- p.38 / Chapter 2.3.2 --- Fertilization and Platygyra acuta larval rearing --- p.38 / Chapter 2.3.3 --- Embryonic development of Platygyra acuta larvae --- p.39 / Chapter 2.3.4 --- Induced settlement --- p.40 / Chapter 2.4 --- Discussion --- p.40 / Chapter 2.4.1 --- Spawning observation --- p.40 / Chapter 2.4.2 --- Embryonic development of Platygyra acuta --- p.43 / Chapter 2.4.3 --- Environmental cues --- p.44 / Chapter 2.4.4 --- "Fertilization, larval rearing and induced settlement" --- p.46 / Chapter 2.5 --- Summary --- p.46 / Chapter Chapter 3 --- "Recruitment Patterns of Scleractinian Corals in Tung Ping Chau Marine Park, Hong Kong" --- p.70 / Chapter 3.1 --- Introduction --- p.70 / Chapter 3.2 --- Methods and Materials --- p.74 / Chapter 3.2.1 --- Site description --- p.74 / Chapter 3.2.2 --- Settlement and survival of coral recruits --- p.74 / Chapter 3.2.2.1 --- Settlement tiles --- p.74 / Chapter 3.2.2.2 --- Concrete blocks --- p.77 / Chapter 3.2.2.3 --- Fouling organisms on settlement tiles --- p.77 / Chapter 3.2.3 --- Environmental parameters --- p.78 / Chapter 3.2.4 --- Post-settlement survival of artificially seeded coral recruits of Platygyra acuta --- p.78 / Chapter 3.2.5 --- Effect of gastropod exclusion on post-settlement survival of coral recruits --- p.79 / Chapter 3.2.6 --- Data analysis --- p.81 / Chapter 3.3 --- Results --- p.82 / Chapter 3.3.1 --- Coral recruitment on settlement tiles --- p.82 / Chapter 3.3.1.1 --- Total settlement --- p.82 / Chapter 3.3.1.2 --- Spatial and temporal patterns of coral recruitment --- p.83 / Chapter 3.3.1.3 --- Growth and health of coral recruit --- p.84 / Chapter 3.3.1.4 --- Competition with other fouling organisms --- p.85 / Chapter 3.3.2 --- Coral recruitment on concrete blocks --- p.88 / Chapter 3.3.3 --- Environmental parameters --- p.89 / Chapter 3.3.4 --- Post-settlement survival of artificially seeded coral recruits of Platygyra acuta --- p.91 / Chapter 3.3.5 --- Effects of gastropod of exclusion on post-settlement survival of coral recruits --- p.92 / Chapter 3.4 --- Discussion --- p.93 / Chapter 3.4.1 --- Coral settlement --- p.93 / Chapter 3.4.1.1 --- Low settlement rate of corals --- p.94 / Chapter 3.4.1.2 --- Possible cause of low coral settlement --- p.96 / Chapter 3.4.2 --- Post-settlement survival of coral recruits --- p.100 / Chapter 3.4.2.1 --- Effect of high sedimentation rate --- p.100 / Chapter 3.4.2.2 --- Competition and predation by other marine organisms --- p.101 / Chapter 3.5 --- Summary --- p.104 / Chapter Chapter 4 --- Summary and Perspectives --- p.126 / References --- p.133

This thesis is encompasses the design, construction, control and testing of an improvement upon the novel soft robotic Jennifish platform. The advancement of this platform includes the addition of light and depth sensors as well increasing the separation of tentacle groups from two to three sets. The final vehicle model consists nine PneuNetstyle actuators divided into three groups of three, molded around a machined Delrin pressure vessel. With a 12V submersible impellor pump connected to each actuator grouping, propulsion is created by the filling and emptying of these tentacles with surrounding ambient water. The Jellyfish2.0 is capable of omnidirectional lateral movement as well as upward driven motion. The vehicle also has a temperature sensor and IMU as did the previous of this platform. Qualitative free-swimming testing was conducted, recorded and analyzed as well as quantitative inline load cell testing, to create a benchmark for comparison with other jellyfish like robots. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2019. / FAU Electronic Theses and Dissertations Collection

Understanding the dynamics of open marine populations is difficult. Ecological processes may vary with the spatial structure of the habitat, and this variation may subsequently affect demographic rates. In a series of observational and experimental studies in the Bahamas, I examined the roles of emigration, mortality, and predation in the local population dynamics of juvenile coral-reef fishes. First, I documented mortality and emigration rates in populations of bluehead and yellowhead wrasse. Assuming that all losses were due solely to mortality would have significantly underestimated survivorship for both species on patch reefs, and for yellowheads on continuous reefs. Mortality differed between species, but emigration did not differ between species or reef types. Mortality of blueheads was density-dependent with respect to both conspecific density and total wrasse density on continuous reefs. In contrast, mortality of yellowheads varied inversely with the density of blueheads on patch reefs. Emigration rates varied inversely with distance to the nearest reef inhabited by conspecifics. In subsequent experiments, I manipulated densities of yellowhead wrasse and beaugregory damselfish, and determined that the relationship between density and mortality varied with reef spatial structure. On natural reefs, mortality rates of the wrasse were highly variable among reefs. On artificial reefs, mortality rates of both species were density-dependent on spatially isolated reefs, yet high and density-independent on aggregated reefs. Heterogeneity in the spatial structure of natural reefs likely caused variation in predation risk that resulted in high variability in mortality rates compared to artificial reefs. A final experiment demonstrated that a single resident predator caused substantial mortality of the damselfish, regardless of reef spacing. Patterns suggested that resident predators caused density-dependent mortality in their prey through a type 3 functional response on all reefs, but on aggregated reefs this density dependence was overwhelmed by high, density-independent mortality caused by transient predators. These results (1) suggest post-settlement movement should be better documented in reef-fish experiments, (2) demonstrate that the role of early post-settlement processes, such as predation, can be modified by the spatial structure of the habitat, and (3) have ramifications for the implementation of marine reserves. / Graduation date: 2004

Global warming from anthropogenic greenhouse gas emissions causes temperature increases in aquatic ecosystems. The rise in environmental temperatures places sensitive organisms under thermal stress. Reef-building corals are a critically important group of animals that provide many ecosystem services for coral reef ecology and the economy and are at a high risk of loss from thermal stress. Thermal stress causes corals to lose their colour, i.e. become bleached, resulting from the loss of symbiont zooxanthellae. This diminishes the energetic benefits that zooxanthellae provide to corals leading to a decline in coral health and high mortality rates. However, corals are also predators and can thus draw nutrients from zooplankton prey to supplement their nutritional requirements. This study investigated whether heterotrophic feeding can ameliorate the effects of thermal stress on coral physiology by providing an alternative energy source to zooxanthellar photosynthesis. Fragmented Pocillopora damicornis coral colonies were exposed to daily maximum temperatures of up to 31°C while being either starved or fed. During the experimental period coral nubbins were monitored for changes in polyp extension, oxygen consumption rate, feeding rate, colour, chlorophyll a content, zooxanthellae density, antioxidant potentials and DNA integrity during stress and after a short recovery period. It was found that, as expected, coral polyp extension, oxygen consumption rate, colour health, chlorophyll a content, zooxanthellae density and DNA integrity were all adversely affected by thermal stress. This indicted that all these measurements were viable biomarkers for assessing the negative effects of thermal stress on coral health. Coral colour, oxygen consumption rate, chlorophyll a content, lipid content, antioxidant potential and DNA integrity were all significantly improved by feeding. These results indicate that feeding does play a role in improving overall coral health and supports the physiological processes in coral tissue during and after thermal stress. The conclusions from this study also have great significance for coral reef ecology and management as predictions of reef resilience can be made from zooplankton ecology and boosting zooplankton availability to corals may be considered to mitigate the harmful effects of thermal stress and bleaching. / M.Sc. University of KwaZulu-Natal, Durban 2013.

Thesis (M.S.)--University of Hawaii at Manoa, 2006. / Includes bibliographical references (leaves 32-38). / v, 38 leaves, bound 29 cm