Three experiments were carried out with laboratory reared Acanthaster planci larvae. In all experiments larvae were transferred to culture dishes containing 80 ml of artificial seawater with no thyroxine added (controls) and thyroxine added at different concentrations. Larval density was less than 1 larva/ml. Unicellular algae were supplied to control and thyroxine cultures at the same density. All cultures were maintained in a 27°C constant temperature room. Larvae at various stages of development, but with most being at the mid-brachiolaria stage, were transferred to control culture dishes and culture dishes containing thyroxine at one of three concentrations (10^-6M, 10^-7M, 10^-8M). The stage of larval development was recorded after 26 hours.The effect of thyroxine on larval settlement was investigated by adding coral fragments with crustose coralline algae on their surfaces to control cultures and cultures exposed to two concentrations of thyroxine (10^-7M, 10^-8M) to induce settlement. The experiment was terminated 3 days later when all of the larvae in some of the culture dishes had settled. Coral fragments were removed so that all surfaces could be inspected microscopically and the number of settled (attached, metamorphosing) larvae and juvenile starfish counted. To more precisely quantify development acceleration by thyroxine, early-brachiolaria-stage larvae were transferred to control dishes and dishes containing one of three thyroxine concentrations (10^-7M, 10^-8M, 10^-9M). After 2 days larvae were measured and the development stage of each larva recorded. Thyroxine accelerates adult rudiment development in sea urchin larvae. This study was undertaken to examine whether larvae of the crown-of-thorns starfish, Acanthaster planci, exhibit a similar response to thyroxine.

In this study, aspects of the physical oceanography, groundwater and pore-water chemistry, and the geochemical and microbiological compositions of sediments have been investigated in the Bonaparte Basin. In particular, we have studied the outer shelf margins of the Timor Sea, in and around the Cartier Trough and Karmt Shoals, looking for evidence of hydrocarbon and groundwater vents associated with the giant Halimeda mounds. Previous work in this region had identified an apparently strong relationship between the location of hydrocarbon seeps and carbonate bank development. A few sites on the seaward margin of Pee and Karmt shoals were identified where surface sediment pore water was greatly enhanced in activities of 224Ra, 223Ra, 228Ra, and 226Ra, which should be an indicator of groundwater inputs. Some of these sediments also had above background concentrations of ultraviolet fluorescence (UVF) detected hydrocarbons. No convincing evidence of seeps from water column salinity, temperature, optical backscatter or oxygen profiles were found, but the radium isotope activity ratios were useful in suggesting that the water sources for this region were likely from the South China Sea via the Indonesian Throughflow (ITF).Geochemical analyses of bulk sediment grab samples of this region showed the expected aragonite (high Sr) dominance on the Halimeda mounds. We also found a zone of Al and Fe enhancement in the dominantly carbonate (Halimeda, foram, pteropod ooze) sediments seaward of the mounds. One radio-chemically dated core from these sediments indicated significant variations in marine and terrestrial (aeolian?) inputs over several centuries of deposition. A consortium of researchers is now being assembled to specifically locate the hydrocarbon and groundwater vents, and determine the influence of these energy and nutrient inputs on the unique biological diversity of these spectacular 400 m high mounds. The scientific objectives of this research was to:1. Search for hydrocarbon/groundwater seeps near Halimeda mounds in the Pee Shoals to Karmt Shoals region, shelf and slope using on-board chemical and radiochemical tracers and to test new methane and oxygen sensors on the CTD frame. 2. Devise methods to estimate carbon (organic and carbonate) burial rates, as a carbon sink or source, and obtain samples of Halimeda for biomass and identification by testing existing sediment sampling gear for use on and around the mounds.3. Preserve samples for nutrient, trace metal, hydrocarbon, radionuclide and microbiological studies to characterise potential study sites.4. Synthesize these preliminary results and develop plans for longer term, integrated and multi-institutional studies of these seep ecosystems.

In 2000, coral diversity at 57 sites in Milne Bay Province was assessed during the Marine RAP survey. This was the second Marine RAP survey to be conducted in Milne Bay Province and focused on sites not previously visited in the 1997 survey. The list of sites includes 16 sites on the mainland in the Milne Bay area, 5 sites in the D'Entrecasteaux Islands, 7 sites in the Amphlett Island Group, 26 sites in the Louisiade/ Conflict Islands and 3 sites in the vicinity of the Engineer Group and Basilaki-Sideia islands.Sites surveyed included a diverse range of habitats encompassing reefs and sediments within and around reefs. Habitats included sandy areas, walls, overhangs, slopes and shallow reef areas. The survey method consisted of direct underwater observation of corals, usually during a single 70 minute dive at each site. Corals were recorded on a slow ascent from the base of the reef, along a zigzag path to the shallowest part of the reef. The primary group of corals surveyed were the zooxanthellate scleractinian corals. In addition, a small number of other coral taxa, which also contribute to the reef matrix were recorded. These include zooxanthellate non-scleractinian corals (Heliopora, Tubipora and Millepora), azooxanthellate scleractinian corals (Tubastrea, Dendrophyllia and Rhizopsammia) and azooxanthellate non-scleractinian corals (Distichopora and Stylaster).Corals that could not be identified in the field were photographed in situ and representative samples were collected and labelled for later identification. The aim of this component of the survey was to compile an inventory of corals on the reefs of Milne Bay Province, Papua New Guinea. The Marine Rapid Assessment Program (RAP) is an initiative of Conservation International (CI). Surveys were carried out in collaboration with the Milne Bay Provincial Government.

To investigate the potential nutrient enrichment of corals by fish wastes, Acropora kenti, Pocillopora verrucosa, Poritesa lutea and Platygyra daedalea colonies were collected from the GBR in Feb 2022, then returned to AIMS's National Sea Simulator. Coral were sampled for protein/symbiont density, then fragmented into smaller (~10g) pieces and aloowed to recover and acclimate to the captive conditions for 1.5 months. Corals were then randomally allocated to treatments where they were either 1) kept with a school of 10 juvenile Chromis viridis fed a pelleted diet, 2) supplied filtered water from a tank housing C. viridis, 3) fed live feeds (enriched Artemia/rotifers and microalgae mix) whilst maintained with C. viridis, 4) supplied only with the live feeds, 5) supplied with a pelleted fish diet without C. viridis, and 6) not supplied feeds and without C. viridis, with four replicate tanks per treatment. During the experiment survival of corals was monitored, growth was measured using bouyant weight and photosynthetic efficiency tracked using dark adapated maximum quantum yield (Fv/Fm). At the end of the experiment, a subset of the samples were frozen and tissue stripped using high-pressure air and filtered seawater. The resulting tissue slurry was homogenised, then used to measure protein contect via a BCA assay and symbiont density using a BD Acurri C6 Flow Cytometer. Water quailty samples were taken weekly throughout the experiment, and analysed for NH4, NO2, NO3, PO4, DOC, PN and PC. Fish were anaethatised using Aqui-S at the end of the experiment and weighed.

Glass microscope slides placed in square polyvinyl chloride frames (112 per grid), exposing the top surface to the seawater, were deployed at Davies Reef, on the Great Barrier Reef at two depths - 4 m (shallow) and 10 m (deep) - within each of 2 sites. To allow biofilm development, slides were maintained at site 1 for 2, 4, and 8 weeks, and at site 2 for 8 weeks prior to the November 2000 mass coral spawning. Slides were used in larval metamorphosis assays, with a minimum of 20 replicate biofilm slides randomly selected for each treatment. To determine biofilm community composition, an additional 30 slides were randomly selected for DNA extraction, 30 slides for fluorescence in situ hybridization (FISH), and 10 slides for scanning electron microscopy (SEM).Coral larvae used in the metamorphosis assays were raised from gametes collected from live colonies of the reef-building coral Acropora microphthalma, from a depth of 6 to 8 m on a fringing reef of Pelorus Island, Great Barrier Reef. Slides were sorted according to whether or not they induced larval metamorphosis, and replicate slides were processed for SEM, FISH, and denaturing gradient gel electrophoresis (DGGE). Sequences of oligonucleotide probes used for FISH. DGGE: the 16S rRNA genes were amplified by PCR with bacterial and eukaryotic primers.Estimates were made of the relative densities of specific probe-targeted bacteria and archaea (Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Actinobacteria, Firmicutes, Cytophaga-Flavobacterium, Bacteroidetes, Planctomycetales, Archaea). The importance of three factors (depth, time, and CCA presence) in inducing larval metamorphosis was investigated in an unbalanced repeated-measures analysis of variance (type IV SS; SPSS version 11).Quantitative estimates of biofilm community composition were made using group-specific FISH probes. All densities are expressed as a percentage of total bacterial numbers obtained using dual hybridization reactions with the bacterium-specific probe EUB338. A principal-component analysis (PCA) was used to summarize biofilm community composition using FISH data in which depth of biofilm formation and exposure time of slides were the variables. Cluster analysis was used to identify replicates that generated similar DGGE profiles. To examine the community structure of developing coral reef biofilms and their ability to induce the metamorphosis of coral larvae.To examine the role microorganisms not associated with calcareous coralline algae in coral metamorphosis.

The study was conducted in 3 seagrass beds in Awerange Bay during the dry season (September 2006) and the wet season (March 2007).Densities of seagrass (shoots m-2) and production in(g DW m-2 d-1) were calculated.pH and redox potential were measured. Water content, total C, total N, TOC and total P were determined, and total inorganic carbon calculated.Rates of sulfate reduction were measured.Solute fluxes of DIC, O2, and dissolved inorganic nutrient and other solute (Ca, Fe, Mn, hydrogen sulphide) across the sediment-water interface were measured.Net ammonium production was measured from each site.Denitrification was measured using the N2-gas technique. Fluxes of methane and N2O were measured. Nitrogen fixation in sediments was also measured.Benthic microaglal production was measured by oxygen fluxes in the dry and wet seasons. To examine sediment carbon and nitrogen cycling in seagrass meadows across a gradient of increasing cabonate content.

A tide gauge (WLR) was deployed at the southern end of Helix Reef.Deployment Details:Code: HLX03Instrument: WLR #569Date Deployed: 25/10/1983Date Recovered: 25/05/1984 This WLR was one of an array of instruments deployed for the physical oceanographic component of the Helix Experiment.

Data is in the form of a Microsoft Access databases, excel workbooks and csv files, showing the original data together with site information (GPS coordinates), and date collected. Data is also in the form of a report, which will be a secured (printable, non-editable), searchable, Portable Document Format (PDF) showing the results of the analyses. The aim of the Western Australian Marine Science Institution (WAMSI) DREDGING SCIENCE NODE Project 4.9, is to thoroughly characterise how dredging activities alters reef water quality (i.e. total suspended solids levels (TSS), underwater light levels and photosynthetically active radiation (PAR) i.e. (light attenuation) in terms of temporal and spatial characteristics (including spectral analyses of temporal patterns) and how these changes in water quality impact on coral health. The data are important for developing water quality thresholds for dredging projects and to improve the ability to predict and manage the impact of future projects. Data used to conduct these analyses were from four large scale capital Dredging projects conducted in the Pilbara region of Western Australia using in situ water quality instrumentation, as well as time series photographic images of individual coral heads (available for the Gorgon project at Barrow Island only). Federal Ministerial Approval Statements for the four projects: MS757, MS800, MS840, MS0873, which are searchable on the WA EPA website: http://www.epa.wa.gov.au. These data are available through a data sharing agreement with WAMSI, pending approval of the individual companies.

Data was collected in order to study the benthic metabolic rates and pathways of carbon and nitrogen cycling at shelf sites proximal to impacted catchments on the northern GBR and to less heavily impacted catchments on the far northern GBR shelf.On the far northern shelf, 3 stations (HAY, HAN, BUK) were chosen based on their proximity to in shore coastal reefs, and one (PCB) off the largest river drainage systems on the far northern shelf (Normanby River). On the northern shelf 5 stations (LOW, CNS, FIZ, HIG, RUS) were chosen based on their proximity to coastal reefs and to highly cultivated river catchments.Box core and Kasten core samples were used for analysis of sediment mean grain size (mm); and percent gravel, sand, silt, clay, and water content. Sediments were classified as mud, sand, sandy mud, or muddy sand. Sub-samples were frozen wet and dry weighted to determine water content, and then ground to a fine powder for determination of total carbon and total nitrogen content. Other elements (P, S, Mn, Fe) were determined. Total inorganic carbon was assumed as CaCO3, and was determined by difference between the total carbon and total organic carbon concentrations. Mean particulate element concentrations and molar ratios in sediments for: TC, TOC, CaCO3, TN, S, Fe (% sediment dry weight); P (µg g-1 sediment dry weight); Mn (Average above mangrove peat layer); C:N, N:P, C:S, S:Fe and C:P (molar ratios).Mass sediment accumulation rates (MAR) were determined from gamma spectrometric measurements of 210Pb, 137Cs, and other radionuclides.Solute fluxes across the sediment-water interface were measured using three sets of three closed opaque chambers (volume: 1 l; area: 82 cm2) from which total CO2, O2, and dissolved inorganic nutrient and metal samples were taken. Concentrations of ammonium, nitrite, nitrate and phosphate were determined using automated techniques.Rates of sulfate reduction were measured.Rates of net production of dissolved metals, particulate CO2, and ammonium from sediments at each site were measured and carbonate concentration was calculated from the pH and total CO2 data in estimating the second apparent dissociation constant of carbonic acid at the appropriate temperature and salinity.Nitrification was estimated using the acetylene inhibition technique. Denitrification was measured from replicate sediment samples taken from boxcores using the N2-gas flux technique. Nitrogen fixation in sediments at each site was measured in three to four dark and clear chambers using the acetylene reduction technique. To examine the flow of carbon and nitrogen in sediments of the far northern and northern sections of the Great Barrier Reef continental shelf. FIZ was visited only once in July 2000, but the other stations were sampled in July 2000 (winter), February 2001 (summer), September 2001, September 2002 (dry spring), and February 2003 (summer).This research is a companion to:Alongi DM, Pfitzner J and Trott LA (2006) Deposition and cycling of carbon and nitrogen in carbonate mud of the lagoons of Arlington and Sudbury Reefs, Great Barrier Reef. Coral Reefs 25: 123-143.andAlongi DM, Trott LA and Pfitzner J (2008) Biogeochemistry of inter-reef sediments on the northern and central Great Barrier Reef. Coral Reefs 27: 407-420.

Sea level, currents and winds were measured at several locations on the Great Barrier Reef continental shelf between June and November 1980.Six Aanderaa model RCM4 current meters, recording data at half-hourly intervals, were deployed at Britomart Passage, Brook Island (2 sites), Cape Upstart, Euston Reef, Green Island and Old Reef at depths between 20 and 50m.Seven water level recorders (four Aanderaa model WLR5, two Aanderaa model 3 and one General Oceanic model TG12) recording data at half-hourly intervals using a 56 second integration time, were deployed at Britomart, Carter, Euston, Gilbey, Keeper and Myrmidon Reefs and Coral Creek. Port authorities provided additional sea level and tide data from Gladstone, Townsville and Cairns harbours.Wind and atmospheric pressure data were collected from a Microdata meteorological station installed at Rib Reef (half-hourly). A CSIRO Aanderaa meteorological station provided hourly wind-vector data for Carter Reef. Wind-vector and atmospheric pressure data (3-hourly) for Flinders Reef, Thursday Island, Townsville, Cooktown and Gladstone were obtained from the Commonwealth Bureau of Meteorology.Hydrographic transects from the coast to Myrmidon Reef were carried out monthly. This research was initiated as a component of a study of the physical oceanography of the central region of the Great Barrier Reef. The data collected were used to estimate term balances in the equations for wind-driven shallow-water waves.