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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

An ecological study of a reef-associated zooplankton community of Barbados, West Indies /

Boers, Jacobus Johannes January 1988 (has links)
A reef-associated zooplankton community was monitored at weekly intervals for 53 weeks. Samples were collected from quadrats of dense coral cover using emergence net traps. The numerical and biomass fluctuations of 15 taxonomic groups, 7 size classes and 5 feeding groups of the community were determined both temporally and spatially. The community was composed of abundant and diverse taxa (81) with cyclopoid copepods being the most important taxon. Larger-sized fauna (e.g. amphipods, decapods, mysids, etc.) were the second most important abundance and biomass contributors. Size class analysis illustrated a bimodal size distribution spectrum. The well developed second mode of the spectrum was attributed to substratum characteristics which permitted an enhanced macrofaunal/detritivore presence. Although week to week fluctuations of the abundance/biomass data were marked, diversity indices indicated a persistent and resilient community. The nocturnal vertical migrations of the fauna did not show a persistent pattern with the varying phases of 12 sequentially monitored lunar cycles. Substratum heterogeneity was primarily responsible for the spatial distribution pattern of the fauna. Although the data variance suggested stochasticity, time-series procedures determined that cross-correlations between the numerical abundances of taxa, size classes and feeding groups occurred without a lead or lag. Similar analyses identified chlorophyll a as the important environmental variable and also as a leading indicator of particular taxonomic, size and feeding group abundances. It was concluded that reef-associated zooplankton communities are abundant, diverse assemblages structured by periodicities which in combination act to form important links between tropical, inshore benthic and pelagic ecosystems.
92

Reef fish populations on small coral heads with special reference to the territoriality of Eupomacentrus fuscus.

Luckhurst, Brian Edward January 1972 (has links)
No description available.
93

Reproductive ecology and distritution of the scleractinian coral Fungia scutaria in Kane‘ohe Bay, O‘ahu, Hawai‘i

Lacks, Amy L 08 1900 (has links)
In Hawaii, abundance of the scleractinian Fungia scutaria is thought to have been in decline in recent years due to disturbances to Kaneohe Bay, where an unusually dense population exists. This study examines factors that could limit population growth in this coral. Sexual reproduction occurred throughout the summer. Experimental data from sperm dilution studies suggested that eggs must be released within 2m of a spawning male for successful fertilization to occur. Field surveys indicated that many patch reefs exhibited high enough densities to yield successful fertilization. However, since field surveys found that only a small percentage (1 %) of juvenile corals (5 cm in length) resulted from settled larvae, post-fertilization processes may be limiting successful recruitment. Asexual reproduction appears to be dominant, with 70% of corals occurring in close aggregations, and 93% of these in aggregations made up of a single color-morph. / Thesis (M. A.)--University of Hawaii at Manoa, 2000. Includes bibliographical references (leaves 70-74).
94

The advantage of juvenile coloration in reef fishes

Mahon, Jeffrey L 12 1900 (has links)
Juvenile reef fishes often have a color pattern different from that of adults. It has been theorized that this reduces the aggression received by juveniles from adult conspecifics. This was tested using two species of Labroides cleaning wrasses in which certain-sized individuals can quickly shift back and forth between the adult and juvenile color patterns. Adult Labroides phthirophagus has the same single-male grouping social structure as previously described for L. dimidiatus. Small L. phthirophagus and L. dimidiatus in juvenile coloration shifted to adult coloration when isolated and then quickly shifted back to juvenile coloration when chased by an adult conspecific female. In L. phthirophagus the adult females attacked small cleaners more frequently when they displayed the adult color pattern, indicating that juvenile coloration gives some protection from conspecific aggression. Two other species oflabrids, Thalassoma duperrey and Coris gaimard, showed the ability to shift back to juvenile coloration when aggression was received from con specific adults, although the shift was not nearly as rapid as seen in Labroides species. Dascyllus albisella and Zebrasomajlavescens, common reef fishes, preferred to solicit cleaning (by posing) from the adult-colored L. phthirophagus, indicating that some hosts prefer the adult color pattern. Small L. phthirophagus shifted to adult coloration more quickly when starved than when provided with host fish on which to feed, indicating that the coloration shift is motivated by hunger. Even though juvenile coloration in some fishes may reduce the aggression received from adults, in cleaner wrasses it also reduces food availability, making it advantageous for them to shift to adult-coloration as soon as possible. Cleaner wrasses have developed a quick, reversible coloration shift that allows changing to adult coloration at a small size but allows reversing coloration if too much aggression is received. / x, 59 leaves, bound : ill., maps ; 29 cm.
95

Light attenuation in a nearshore coral reef ecosystem

Jacobson, Ellen C January 2005 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references (leaves 43-44). / vi, 44 leaves, bound ill. (some col.) 29 cm
96

Expression, Turn-Over, Localization, and Transport of Pocilloporins in Reef Building Corals

Jeffry M R Deckenback Unknown Date (has links)
Coral reefs are a critical resource to developing and developed nations world wide. Providing shelter, food, monetary value, and a vast resource of ecological wealth, the corals of the reefs underpin an entire ecosystem. Climate change, driven by increased greenhouse gases, is raising the temperature of Earth’s waters and atmosphere, while making the planet’s oceans increasingly acidic. Brightly lit and increasingly warm tropical waters present a potentially challenging environment in which scleractinian corals grow. In attempting to cope with the competing stresses of intense photon flux density (PFD) and anomalously high sea surface temperatures, corals and dinoflagellates exhibit myriad biochemical and physiological adaptations. Pocilloporins, a diverse group of non-fluorescent green fluorescent protein (GFP) homologs found across Cnidaria and beyond, are one such adaptation within the tissues of heavily pigmented scleractinian corals. Chemically unique amongst pigments, GFP-like pigments exist as pure protein chromophores and exhibit little to no cytotoxicity when naturally occurring. This non-fluorescent class of GFP-like pigments has found popularity in biochemical and biotechnological applications, though an ecological and evolutionary explanation for the heavy conservation of pocilloporins across a broad range of scleractinian corals and related cnidaria is still a subject of scientific research and debate. This thesis supports the hypothesis that pocilloporins act as a naturally occurring photoprotective pigment in reef-building corals, specifically acting to filter and regulate the light environment within coral polyps. In examining the role of pocilloporins in Scleractinia, the need to examine environmental sources of pigment production induction and suppression, the localization of pigments within coral tissues and cells, and the ability of coral colonies to direct resource allocation with regards to pocilloporin production were identified as lines of inquiry. Briefly, for experiments examining either pocilloporin induction or suppression, the following aspects were studied: holobiont responses in the form of mRNA signal expression, host pigment isolation and analysis, dinoflagellate density and pigmentation sampling, and chlorophyll fluorescence of live corals. Blue morph Acropora aspera, common to the reef flat of Heron Island (Great Barrier Reef, Australia), were subjected to 99% shade and thermal bleaching threshold temperatures in separate attempts to suppress pocilloporin expression, while red morph Montipora monasteriata was transplanted at equivalent depth from their natural cave environments to exposed portions of the spur and groove formations of the northern face of Wistari Reef (Great Barrier Reef, Australia). Both ambient temperature and heat-stressed A. aspera were concurrently collected during the thermal stress experiment and placed in preservatives for immuno-histochemical localization of pocilloporins with their tissues. Finally, radio-labelled glycine, a very common amino acid in the primary sequence of pocilloporin, was injected into artificially injured tan morph Montipora monasteriata, also on the northern face of Wistrai Reef to study the uptake of dissolved organic materials (DOM) and incorporation of metabolic resources into newly generated pigments. Pocilloporins proved easier to induce in this work than suppress, and the location of these pigments in A. aspera tissues suggests a potential mechanism. The data demonstrated the presence of pocilloporins in the most directly exposed epidermal and gastrodermal tissues of the coral polyp, specifically the outermost layers of epidermis and gastrodermal layers bordering directly upon the gastrovascular cavity. Closer inspection through anti-pocilloporin-gold stained TEM images was highly suggestive of pocilloporin secretion in coral mucus, a theory separately supported by observations of coral mucus in collected live corals. Neither suppression experiment induced heavy mucus sloughing in A. aspera, so despite multi-fold reductions in pocilloporin mRNA as a result of applied stimuli, the continued presence of pocilloporin aaCP592 in blue morph A. aspera is not surprising. Conversely, pocilloporin msCP576 in plating Montipora monasteriata was induced in response to both general increases in PFD and specific increases of PFD at the sites of physical injury. Additionally, tan morph Montipora monasteriata demonstrated the capacity to collect and allocate DOM from the environment to assist in the production of new pigments and tissues, an energetically expensive process. The reduction of the orange-red spectrum in favour of the blue light ranges is generally beneficial to the photosynthetic systems of both higher plants and the resident dinoflagellates of corals. msCP576 and aa592, both positively identified as pocilloporins within this work, absorb within the orange-red region and apparently act as a photoprotective filter in all exposed surfaces of heavily pigmented corals, enhancing the blue spectrum of incident and reflected PFD and generally regulating the internal light environment.
97

Comprehensive model for modern lagoonal patch reef systems in Discovery Bay, Jamaica

Maher, Marie A. Bonem, Rena Mae. January 2007 (has links)
Thesis (M.S.)--Baylor University, 2007. / Includes bibliographical references (p. 90-92).
98

Interactions between sea urchins and macroalgae in south-western Australia : testing general predictions in a local context /

Vanderklift, Mathew Arie. January 2002 (has links)
Thesis (Ph.D.)--University of Western Australia, 2002. / Thesis (Ph.D.) - University of Western Australia, 2002.
99

Analysis of the effectiveness of Indonesia's coral reef management framework

Dirhamsyah. January 2005 (has links)
Thesis (Ph.D.)--University of Wollongong, 2005. / Typescript. Includes bibliographical references: p. 301-325.
100

Community-based and collaborative management of coral reefs and coastal resources in Palau /

Matthews, Elizabeth, January 2007 (has links)
Thesis (Ph.D.)--University of Rhode Island, 2007. / Includes bibliographical references (leaves 295-311).

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