Thesis (Ph.D.) - James Cook University, 2003. / Computer disc "contains samples of footage from a selection of home movies, documentaries and advertisements for the Great Barrier Reef". Typescript (photocopy). Appendices: leaves 314-353. Bibliography: leaves 275-313.

The study of place has been a component of the recreation literature for about three decades. Most researchers have sought to either describe the cognitive and evaluative beliefs (place meaning) recreational visitors ascribe to a setting or identify the intensity of the human-place bond (place attachment). Few have attempted to qualitatively investigate the meanings visitors ascribe to a setting and quantitatively measure the intensity of their attachment to that setting within the same study design. Nor has there been much work aimed at understanding these concepts in marine environments. In this dissertation, I began to fill these gaps in the literature through the use of a three- phase multiple-method research design. In the first phase, I conducted 20 interviews to identify the meanings that recreational visitors ascribe to the Great Barrier Reef Marine Park (GBRMP) and to further explore how the symbolic interactionist framework can be used to understand place meanings. Ten place meaning themes emerged from the informants' statements. The second phase used 34 items developed from the 10 meaning themes that emerged from the previous interviews and a place attachment scale to explore how recreational visitors' attachment to a marine resource was reflected in their depictions of why the resource is meaningful. Three hundred and twenty-four individuals, living in Queensland, Australia, responded to a postal/email survey conducted during January and February of 2009. The results indicated that all the meanings recreational visitors ascribe to the GBRMP provide context for the attachment they hold for the setting, however particular sets of meanings are important in differentiating between attachment intensity levels. The final phase, which also used the postal/email survey described, identified how place attachment affected the relationship, identified by Stern et al. (1995), between the recreational visitors' environmental world view (EWV) and attitudes toward negative impacts on the reef ecosystem. I found that place attachment partially mediated the relationship between EWV and attitudes toward impacts. The conclusions presented in this dissertation filled in gaps in the recreation literature's understanding of place while providing further insight into how place meaning influences other constructs important to natural resource management.

Climate change is a global issue and the effects on fish populations remain largely unknown. It is thought that climate change could affect fish at all levels of biological organisation, from cellular, individual, population and community. This thesis has taken a holistic approach to examine the ways in which climate change could affect fish from both tropical, marine ecosystems (Great Barrier Reef, Australia) and temperate, freshwater ecosystems (non-tidal River Thames, Britain). Aerobic scope of coral reef fish tested on the Great Barrier Reef was significantly reduced by just a 2°C rise in water temperature (31, 32 and 33°C, compared to the current summer mean of 29°C) due to increased resting oxygen consumption and an inability to increase the maximal oxygen uptake. A 0.3 unit decline in pH, representative of ocean acidification, caused the same percentage loss in aerobic scope as did a 3°C warming. Interfamilial differences in ability to cope aerobically with warming waters will likely lead to changes in the community structure on coral reefs with damselfish replacing cardinalfish. Concerning Britain, there is evidence of gradual warming and increased rainfall in winter months over a 150 year period, suggesting that British fish are already experiencing climate change. It was evident from an analysis of a 15 year dataset on fish populations in the River Thames, that cyprinid species displayed a different pattern in biomass and density to all the non-cyprinid fish population, suggesting that there will be interfamilial differences in responses to climate change. Using a Biological Indicator Approach on the three-spined stickleback, Gasterosteus aculeatus, a 2°C rise in water temperature resulted in a stress response at the cellular and whole organism level. A 6°C rise in temperature resulted in a stress response at the biochemical level (higher cortisol and glucose concentrations), cellular level (higher neutrophil: lymphocyte ratio) and whole organism level (higher ventilation rate and lowered condition factor, hepatosomatic index and growth). G. aculeatus is considered to be temperature tolerant; therefore these results indicate that climate change may prove to be stressful for more temperature-sensitive species. This study has demonstrated that climate change will have direct effects on fish populations, whether they are in temperate regions such as Britain or in tropical coral reefs, but with strong interfamilial differences in those responses.

Scleractinian corals increasingly are studied as geochemical archives of modern- and palaeoclimate, but microsampling for geochemical data is complicated by: 1) the microstructural complexity and spatial variability in skeletal growth in different coral genera; and 2) the rapidity and scale of diagenetic alteration that occurs in living coralla. Geochemical sampling techniques now have spatial resolution into the sub-micrometer to tens of micrometers range, and it is hoped that the spatial resolution can be translated to temporal resolution. This study investigated the effects on geochemical analyses imposed by microstructure and diagenesis in different live-collected coral genera representing somewhat different depositional environments. Suites of samples of four reef-building genera (Acropora, Pocillopora, Goniastrea and Porites) were collected from three adjacent environments in intertidal and subtidal positions near the reef edge at Heron Reef, Great Barrier Reef and studied by means of optical and scanning electron microscopy, combined with vibrational and energy dispersive spectroscopy. The first section of this study compares and documents the microstructure of the four coral genera. Each genus was found to have very different three-dimensional arrangements of microstructural elements, and a new general growth model was proposed for Acropora, to take into account differences in the timing of precipitation of trabeculae and thickening deposits. The results highlight the complexity and spatial variability of skeletal growth in different coral genera. Because microstructural patterns vary in different genera, direct observation of microstructural elements and growth lines are necessary to allow geochemical microsamples to be placed into series that represent temporal sequences with known degrees of time averaging. Coral growth rates (i.e., rates of extension) are discussed to determine the range of temporal relationships that exist between closely spaced skeletal microstructural elements. Such data are necessary in order for coral skeletogenesis to be understood and are critical for constraining microsampling strategies aimed at developing true time series geochemical data at very fine spatial and temporal scales. The second part of the study focused on early diagenetic alteration of the corals, which is an equally important concern for geochemical analysis. Early marine diagenesis was documented in the same live-collected samples of the four common reef-building coral genera. Samples show extensive early marine diagenesis where parts of the coralla less than three years old contain abundant macro- and microborings (sponges, algae, cyanobacteria and fungi) and significant amounts of aragonite, high-Mg calcite, low-Mg calcite and brucite [Mg(OH)2] cements. Many of the cements are associated with microendoliths and endobionts that inhabit recently abandoned parts of the skeleton. The cements are problematic for palaeoclimate reconstruction because geochemical proxies used for paleoclimate studies are meant to reflect ambient seawater chemistry and conditions, but the occurrence of brucite and low-Mg calcite demonstrates how far fluid chemistry in microenvironments within the corals has evolved from ambient seawater. Some Porites lobata specimens have had as much as 60% of the most recently deposited skeletal aragonite (i.e., the part of the skeleton that projects into the layer of living polyps) bored and replaced by low-Mg calcite cement. The low-Mg calcite cement has significantly different trace element ratios (Sr/Ca(mmol/mol) = 6.3 ± 1.4; Mg/Ca(mmol/mol) = 12.0 ± 5.1) than the host coral skeletal aragonite (Sr/Ca(mmol/mol) = 9.9 ± 1.3; Mg/Ca(mmol/mol) = 4.5 ± 2.3), thus providing a serious challenge for Sr/Ca or Mg/Ca based sea surface temperature calculations. This study illustrates that many diagenetic changes that can radically alter important geochemical characteristics of coral skeleton occur very early on the sea floor (i.e., while corals are still alive). Documented cements altered trace element inventories (e.g., Sr and Mg), thus, interfering with the use of those elements in palaeotemperature calculations. Hence, significant diagenetic changes that jeopardise palaeoclimate data do not require long-term diagenesis or meteoric exposure. Some of the diagenetic changes (e.g., calcite filled borings) occur at scales that are very difficult to detect short of visual inspection using SEM. Hence, vetting of coral samples with SEM is required before any sample is subjected to geochemical analysis.

Trajectories of decline have been described in coral reefs throughout the Indo-Pacific region, with long-term losses of abundance, diversity and habitat structure. Since European settlement of the Queensland coastline in the mid-18th century, widespread changes in land use have occurred within Great Barrier Reef (GBR) catchments (e.g. extensive land clearing, agriculture and grazing). Despite direct and indirect evidence indicating decline of inshore reefs, it has proven difficult to ascertain links between land use changes, terrestrial discharge, water quality and the decline of coral reefs at regional scales, and the contributions of anthropogenic influences to the disturbance regimes of inshore reefs remains highly controversial. This thesis uses palaeoecological reconstruction of coral assemblages and high-precision U-Series dating to examine changes in community structure of inshore coral reefs in the Palm Islands region across decadal and centennial scales. Comparisons of modern and historical coral assemblages provide evidence of a collapse of Acropora coral communities at Pelorus Reef in the early 20th Century. Fossil assemblages in an adjacent site at Pelorus provide further evidence of an extrinsic shift from historical Acropora assemblages to more sediment-tolerant corals in modern assemblages, a change without precedence in 800 years of record. Sediment cores (2-5m length) were extracted from Pandora and Havannah reefs to determine long-term rates of reef growth throughout the late Holocene. Computer Axial Tomography (CAT) scans of cores revealed a framework dominated by coral fragments, and U-Series dating of corals revealed rapid and continuous reef growth at both reefs throughout the last 1000 yrs. Comparisons of reef accretion (m ka-1) from cores with published accretion rates from early-mid Holocene inshore GBR reefs show that reef slope environments are now accreting at rates equal to and exceeding those of the last 8000 years. This result contradicts assumptions that inshore reefs are undergoing or have undergone natural trajectories of geomorphic decline. A bayesian approach to determine stability of coral communities from the Pandora and Havannah cores indicates that those coral communities have existed in stable states for upwards of 400yrs, punctuated by periods of instability. Contrary to some paradigms of biodiversity, the high diversity communities were unstable on centennial scales, 4 yet the low diversity assemblages did not necessarily confer stability to these assemblages. Growth rates of inshore reefs were independent of diversity or community structure. From a management perspective, these results provide a longer-term (decades to centuries) understanding of coral community dynamics on inshore reefs of the GBR that provides a basis for detecting and understanding changes following European settlement, and a baseline for the management and potential restoration of coral communities at local and regional scales.

No abstract available

This study examines the biology of the venus tuskfish Choerodon venustus from the southern Great Barrier Reef to enable better-informed management decisions. Venus tuskfish are taken almost exclusively by line fishing. The size of the catch is uncertain, but the annual Queensland commercial catch is probably about 30 t and the recreational catch much greater than this (possibly ca. 300 t). The species is not the primary target of fishers and can be regarded as by-catch taken while targeting other species. However C. venustus is the second or third most commonly retained species in the study area. Venus tuskfish are taken in habitats associated with coral and other reefs across a depth range from 5 m to 90 m. The species is a benthic predator, taking molluscs, echinoderms, annelids, arthropods, and fish (in decreasing order of importance). Feeding intensity was greatest in summer. There was evidence of complex feeding behaviours and a dominance hierarchy amongst feeding fish that may result in large males being more susceptible to fishing. The species is slow growing and long lived. Up to 38 bands were observed on the opercular bones of C. venustus. Back-calculation methods yielded von Bertalanffy growth parameters of L¥ =669 mm, K = 0.09 and t0 = -3.89. Male fish appear to grow faster than females. This may be related either to faster growing fish becoming males, growth acceleration following sex reversal, or both. Selective removal of faster growing males in heavily fished locations may result in a greater proportion of slower growing females in the remaining population. iv Choerodon venustus is a protogynous hermaphrodite; the proportion of males increases as the fish increase in size, transitional fish exist and remnant female tissue was evident in testes. The species is a serial spawner with an extended breeding season perhaps peaking in autumn and around the new and full moon. Females mature between 200 and 250 mm forklength (LCF). Venus tuskfish display sexually dimorphic colouration and appear to have a socio-sexual group structure. Fish occur in extended groups with several large males associated with a larger number of smaller females. Multiple sex-reversals may occur in the groups perhaps in response to the loss of the larger males. Large females produce over 100,000 eggs in the ovaries. The number of eggs released at each spawning is unknown. There is a direct cubic relationship between length and the weight of female gonads. Large females over 500 mm LCF are capable of producing over 20 times the number of eggs of small mature females (around 250 mm LCF). The locations sampled showed marked differences in fishing effort. The Capricorn Bunker Group was subject to much higher fishing effort than the Swains Reefs. Estimates of fishing mortality reflected this trend. Line fishing selects large male fish. The heavily fished Masthead Island had smaller males, females and transitional fish. Fish below 300 mm LCF were not captured efficiently. Venus tuskfish may be capable of modifying their life cycle in response to increased fishing mortality. Sex reversal may be related to the absence of large males in social groups. Hence sex ratio remains constant between fished and unfished locations. In heavily fished populations, females are smaller and consequently produce fewer eggs. Modeling suggests unfished areas may have a potential fecundity over six times that of those heavily exploited. Choerodon venustus are severely impacted by barotrauma during capture, and few captured and released fish are likely to survive. There are special challenges in managing venus tuskfish including: · Their status as a largely bycatch species; · The poor survival of released fish due to barotrauma; · A lack of good measures of catch and effort caused by inconsistent naming of the species and inherent errors in current data collection methods; · Their extended spawning period and likely widespread spawning sites and · The need to support group fecundity by protecting larger fish. A combination of a series of fish reserves, raising the minimum legal size to 36 cm TL, effective catch limits and an effective education program are likely to support the sustainability of the fishery.

Thesis (Ph.D.) - James Cook University, 2005. / Typescript (photocopy) Bibliography: p. 511-553.

Ecologists have long questioned why fluctuating populations tend to persist rather than go extinct. Populations that persist indefinitely are regulated by mechanisms that cause demographic density dependence, which works to bound fluctuation above zero. In a series of studies, I have sought to determine the processes and mechanisms that regulate local populations of coral-reef fish. In the Exuma Keys, Bahamas, fairy basslets (Gramma loreto) live in aggregations on the undersides of coral-reef ledges. These aggregations often constitute local populations because movement between aggregations is rare. The largest individuals occupy prime feeding positions near the front of ledges and force smaller individuals remain near the back where they have lower feeding rates. Based on these initial observations, I designed two experimental studies of the demographic consequences of variation in basslet density. In the first study, I manipulated the density of newly-settled fish to explore the effects of high recruitment on population size. Populations with experimentally elevated recruitment converged in density with unmanipulated populations, primarily due to density-dependent mortality. I found no evidence that density dependence was caused by intraspecific competition; rather it appeared to be due to a short-term behavioral response by predators (aggregative and/or type 3 functional response). In a second study, I manipulated the densities of adults among populations with a standard average density of newly-settled fish. Two measures indicated that the intensity of competition increased at higher densities of adults, which likely made small fish more susceptible to predation, thereby causing density-dependent mortality. Long-term observations indicated that basslet populations were regulated at temporal scales exceeding two generations. At Lizard Island on the Great Barrier Reef, I also examined how patterns of recruitment of coral-reef fishes were modified across a range of natural recruit densities in the presence and absence of resident predators. Predators decreased recruitment and increased mortality for all species, but these effects varied considerably among species. The results of each of these studies stress the importance of both competitive and predatory mechanisms in modifying patterns of abundance established at the time of larval settlement, as well as regulating local population size. / Graduation date: 2002

This thesis describes the chemical investigations of several ascidian species collected from the Great Barrier Reef, Queensland, Australia. The thesis is divided into two separate components, Part A focuses on the isolation and structure elucidation of 11 previously undescribed ascidian metabolites. All structures were assigned using a combination of spectroscopic and/or chemical methods. Part B relates to the isolation and chemical conversion of a natural product to a combinatorial template. The natural product template was subsequently used in the generation of a solution-phase combinatorial chemistry library. A further two combinatorial libraries were generated from a synthesised model compound that was related to the natural product template. Part A. Investigation of Aplidium longithorax collected from the Swains Reefs resulted in the isolation of two new para-substituted cyclofarnesylated quinone derived compounds, longithorones J (30) and K (31). The former compound had its absolute stereochemistry determined by the advanced Mosher method. From an Aplidium longithorax collected from Heron Island, two new cyclofarnesylated hydroquinone compounds, longithorols C (46) and D (47) and a novel macrocyclic chromenol, longithorol E (48) were isolated. Longithorol C (46) had its absolute stereochemistry determined by the advanced Mosher method. Chemical investigation of the deep-purple colonial ascidian, Didemnum chartaceum collected from Swains Reefs led to the isolation of five new lamellarin alkaloids, which included the 20-sulfated derivatives of lamellarins B (94), C (95) and L (96), the 8-sulfated derivative of lamellarin G (97) and the non-sulfated compound, lamellarin Z (98). The known lamellarins A (63), B (80), C (64), E (65), G (67), and L (71) plus the triacetate derivatives of lamellarin D (82) and N (83) were also isolated. An aberration in the integration of signals in the 1H NMR spectra of the 20-sulfated derivatives (94-96) led to NMR relaxation studies. T1 values were calculated for all protons in the sulfated lamellarins (94-97) and their corresponding non-sulfated derivatives (80, 64, 71, 67). The protons ortho to the sulfate group in compounds (94-97) had T1 values up to five times larger than the corresponding protons in their non-sulfated derivatives (80, 64, 71, 67). A specimen of Eudistoma anaematum collected from Heron Island was shown to contain a new b-carboline alkaloid, eudistomin V (130), in addition to the two known metabolites, eudistomin H (105) and I (106). Part B. The known natural products, 1,3-diphenethylurea (29), 1,3-dimethylxanthine (30), 1,3-dimethylisoguanine (31) and the salts of tambjamine C (16), E (18) and F (19) were isolated from the ascidian, Sigillina signifera collected in Blue Lagoon, Lizard Island. Base hydrolysis on mixtures of the salts of tambjamine C (16), E (18) and F (19) resulted in the production of 4-methoxy-2,2-bipyrrole-5-carbaldehyde (26). This natural product template (26) was used in the generation of an enamine combinatorial chemistry library (98, 103-111) using solution-phase parallel synthesis. The biaryl compound, 4-(2-thienyl)-1H-pyrrole-2-carbaldehyde (59) was successfully synthesised using Suzuki-Miyaura coupling conditions and subsequently used as a template in the generation of an amine (67, 77, 80-87) and imine (78, 92-95) combinatorial library using solution-phase parallel synthesis.