Northeast Coast Of Australia Research Articles

A note on East Australia Group V Stock humpback whale movement between feeding and breeding areas based on photo-identification

Documentation of humpback whale migratory movements between Australasia and the Southern Ocean has been limited almost exclusively to historical whaling data. This study examines photographic evidence documenting the movements of three individual humpback whales between their breeding grounds on the northeast coast of Australia and feeding grounds in Area V of the Southern Ocean. Although these individuals exhibited marked site fidelity to the same low latitude breeding grounds, their sightings in high latitude feeding grounds vary by 35° longitude, confirming dispersal of Eastern Australia Group V Stock humpback whales in the Antarctic feeding ground.

Impact of a Tropical Cyclone on Terrestrial Inputs and Bio-Optical Properties in Princess Charlotte Bay (Great Barrier Reef Lagoon)

In January 2013, tropical cyclone Oswald caused widespread flooding in the North-East coast of Australia, and large and highly episodic inputs into Princess Charlotte Bay (PCB, northern Great Barrier Reef). Freshwater outflows from the Normanby and Kennedy rivers, the two main rivers draining the adjacent catchments, resulted in drastic changes in physical, biogeochemical and optical properties within PCB. On 31 January, 2 days after the peak riverine discharge from the Normanby river, nutrients and dissolved organic matter contents peaked under the influence of large outflows from the Kennedy river into the western section of the bay (5.8 μM for dissolved inorganic nitrogen, 6.9 g m−3 for dissolved organic carbon and 6.1 m−1 for the colored dissolved organic matter absorption coefficient at 412 nm). In the eastern section of the bay, the situation appeared more ‘mixed’, with a suspended solids concentration reaching 23.1 g m−3 close to the Normanby river mouth. The main phytoplankton bloom occurred in the transition zone between the Kennedy and Normanby flood plumes, and was dominated by diatoms with a chlorophyll a concentration reaching 14.6 mg m−3. This study highlights the need to better describe the critical spatial and temporal scales of variability of key biogeochemical and optical properties after a major flood event. The data collected is key to improve the accuracy of ocean color remote sensing algorithms and regional biogeochemical budgets following highly episodic inputs.

Beyond bridge and barrier: Reconceptualising Torres Strait as a co-constructed border zone in ethnographic object distributions between Queensland and New Guinea

For over 200 years, Western scholarship has presented Torres Strait variously as a bridge and barrier to cultural influences between mainland New Guinea and Australia. An alternative approach is to see Torres Strait as neither a bridge (permeable boundary) nor a barrier (impervious boundary) but as a socially and culturally co-constructed border zone. Central to this new approach is conceptualisation of the Coral Sea Cultural Interaction Sphere (CSCIS) that centres on a series of ethnographically-known, canoe-based, long-distance maritime exchange networks that linked communities and information on objects over a distance of 2000 km along the south coast of Papua New Guinea and the northeast coast of Australia. The CSCIS emphasises Indigenous agency and the shared/selective uptake of objects and ideas by potential recipient communities across Torres Strait and their New Guinea neighbours to the north and mainland Australian neighbours to the south. Object distribution maps created using data derived from anthropological texts and museum online catalogues reveal continuities and discontinuities in the distribution of selected objects across the study area. These maps illustrate three forms of object uptake: (1) shared uptake of double-outrigger canoes and bamboo smoking pipes between New Guinea, Torres Strait and Australia; (2) selective uptake of dog-tooth necklaces and cone shell armbands between New Guinea and Torres Strait and not Australia; and (3) selective uptake of nautilus bead headbands and shell-handled spearthrowers between Australia and Torres Strait and not New Guinea. Archaeological evidence for temporal changes in the geographical spread of pottery indicates that the CSCIS was historically dynamic, with numerous reconfigurations over the past 3000 years. Enhanced understanding of the CSCIS requires the addition of contemporary Indigenous perspectives.

First tracking of the oceanic spawning migrations of Australasian short-finned eels (Anguilla australis)

Anguillid eel populations have declined dramatically over the last 50 years in many regions of the world, and numerous species are now under threat. A critical life-history phase is migration from freshwater to distant oceans, culminating in a single life-time spawning event. For many anguillids, especially those in the southern hemisphere, mystery still shrouds their oceanic spawning migrations. We investigated the oceanic spawning migrations of the Australasian short-finned eel (Anguilla australis) using pop-up satellite archival tags. Eels were collected from river estuaries (38° S, 142° E) in south-eastern temperate Australia. In 2019, 16 eels were tracked for up to about 5 months, ~ 2620 km from release, and as far north as the tropical Coral Sea (22° S, 155° E) off the north-east coast of Australia. Eels from southern Australia appeared to access deep water off the Australian coast via two main routes: (i) directly east via Bass Strait, or (ii) south-east around Tasmania, which is the shortest route to deep water. Tagged eels exhibited strong diel vertical migrations, alternating between the warm euphotic zone (~ 100–300 m, 15–20 °C) at night and the mesopelagic zone (~ 700–900 m, 6–8 °C) during the day. Marine predators, probably lamnid sharks, tuna, or marine mammals, ended many eel migrations (at least ~ 30%), largely before the eels had left the Australian continental shelf. The long and risky marine migrations of Australasian eels highlight the need for better information on the processes contributing to eel mortality throughout the life cycle, including the impacts of future changes to oceanic currents, predator abundance and direct anthropogenic disturbances.

Characterization of aerosols over the Great Barrier Reef: The influence of transported continental sources

The rapid environmental changes in Australia prompt a more thorough investigation of the influence of transportation, local emissions, and optical–chemical properties on aerosol production across the region. A month-long intensive measurement campaign was conducted during spring 2016 at Mission Beach, a remote coastal site west of the Great Barrier Reef (GBR) on the north-east coast of Australia. One aerosol pollution episode was investigated in early October. This event was governed by meteorological conditions and characterized by the increase in black carbon (BC) mass concentration (averaged value of 0.35 ± 0.20 μg m−3). Under the influence of the continental transportation, a new layer of nucleation-mode aerosols with an initial size diameter of 20 nm was observed and aerosol number concentrations reached the peak of 6733 cm−3 at a diameter of 29 nm. The averaged aerosol extinction coefficient at the height of 2 km was 150 Mm−1, with a small depolarized ratio (3.5–5%). Simultaneously, the boundary layer height presented a fall–rise trend in the presence of these enhanced aerosol concentrations and became stable in a later stage of the episode. We did not observe clear boundary layer height diurnal variations from the LiDAR observations or from the Weather Research and Forecasting (WRF) model outputs, except in an earlier stage of the aerosol episode for the former. Although the sea breeze may have been responsible for these particles, on the balance of available data, we suggest that the aerosol properties at the GBR surface during this period are more likely influenced by regional transportation of continental sources, including biomass-burning aerosols.

Behavior of diatomaceous soil in lacustrine deposits of Bogotá, Colombia

This work presents a study on the behaviors of diatomaceous soils. Although studies are rarely reported on these soils, they have been identified in Mexico City, the Sea of Japan, the northeast coast of Australia, the equatorial Pacific, and the lacustrine deposit of Bogotá (Colombia), among other locations. Features of this kind of soil include high friction angle, high initial void ratio, high compressibility index, high liquid limit, and low density. Some of these features are counterintuitive from a classical soil mechanics viewpoint. To understand the geotechnical properties of the diatomaceous soil, a comprehensive experimental plan consisting of more than 2400 tests was performed, including physical tests such as grain size distribution, Atterberg limits, density of solid particles, and organic matter content; and mechanical tests such as oedometric compression tests, unconfined compression tests, and triaxial tests. Laboratory tests were complemented with scanning electron microscope (SEM) observations to evaluate the microstructure of the soil. The test results show that there is an increase in liquid limit with increasing diatomaceous content, and the friction angle also increases with increasing diatomaceous content. In addition, several practical correlations were proposed for this soil type for shear strength mobilization and intrinsic compression line. Finally, useful correlations were presented, such as the relationship between the state consistency and the undrained shear strength, the friction angle and the liquid limit, the void ratio at 100 kPa and the liquid limit, the plasticity index and the diatomaceous content, among others.

Isotopic (U-Pb, Nd) and geochemical constraints on the origins of the Aileu and Gondwana sequences of Timor

Detrital zircon U-Pb age data collected from the argillitic sedimentary rocks of the Timorese Aileu Complex and Gondwana Sequence indicate that both units were derived from a common source containing 200–600Ma, 900–1250Ma and 1450–1900Ma zircon. The modally most significant age population within this range of ages dates to c. 260Ma. The observed spectrum of ages can be traced to the eastern active margin of Pangaea and its immediate foreland, which today is best exposed along the northeast coast of Australia. Compared to the relative homogeneity of the detrital zircon age data, geochemical and Nd isotopic data show that the mudstones of the Aileu Complex are on average more siliceous, have higher K2O/Na2O, Rb/Sr, Th/Sc and yield notably older Nd TDM model ages when compared to those from the Gondwana Sequence. These data are interpreted to suggest that, although both sequences share a common east Pangaea provenance, they were eroded from different sections of this active margin and deposited in spatially separated basins. The present proximity of these units is a result of their tectonic juxtaposition during the Pliocene to Recent collision between the northern edge of the Indo–Australia plate and the Banda Arc.

Towards protecting the Great Barrier Reef from land-based pollution.

The Great Barrier Reef (GBR) is an iconic coral reef system extending over 2000km along the north-east coast of Australia. Global recognition of its Outstanding Universal Value resulted in the listing of the 348000 km(2) GBR World Heritage Area (WHA) by UNESCO in 1981. Despite various levels of national and international protection, the condition of GBR ecosystems has deteriorated over the past decades, with land-based pollution from the adjacent catchments being a major and ongoing cause for this decline. To reduce land-based pollution, the Australian and Queensland Governments have implemented a range of policy initiatives since 2003. Here, we evaluate the effectiveness of existing initiatives to reduce discharge of land-based pollutants into the waters of the GBR. We conclude that recent efforts in the GBR catchments to reduce land-based pollution are unlikely to be sufficient to protect the GBR ecosystems from declining water quality within the aspired time frames. To support management decisions for desired ecological outcomes for the GBR WHA, we identify potential improvements to current policies and incentives, as well as potential changes to current agricultural land use, based on overseas experiences and Australia's unique potential. The experience in the GBR may provide useful guidance for the management of other marine ecosystems, as reducing land-based pollution by better managing agricultural sources is a challenge for coastal communities around the world.

Using satellite altimetry and tide gauges for storm surge warning

Abstract. The combination of the coarse temporal sampling by satellite altimeters in the deep ocean with the high temporal sampling at sparsely located tide gauges along the coast has been used to improve the forecast of high water for the North Sea along the Danish Coast and for the northeast coast of Australia. For both locations we have tried to investigate the possibilities and limitations of the use of satellite altimetry to capture high frequency signals (surges) using data from the past 20 years. The two regions are chosen to represent extra-tropical and tropical storm surge conditions. We have selected several representative high water events on the two continents based on tide gauge recordings and investigated the capability of satellite altimetry to capture these events in the sea surface height data. Due to the lack of recent surges in the North Sea we focused on general high water level and found that in the presence of two or more satellites we could capture more than 90% of the high water sea level events. In the Great Barrier Reef section of the northeast Australian coast, we have investigated several large tropical cyclones; one of these being Cyclone Larry, which hit the Queensland coast in March 2006 and caused both loss of lives as well as huge devastation. Here we demonstrate the importance of integrating tide gauges with satellite altimetry for forecasting high water at the city of Townsville in northeast Australia.

Phylogenetic Diversity and Endemism: Metrics for Identifying Critical Regions of Conifer Conservation in Australia

Accurately and sufficiently quantifying biodiversity is integral for conservation. Traditional metrics for measuring biodiversity, species richness (SR) and weighted endemism (WE), do not take into account the evolutionary history of organisms. Phylogenetic diversity (PD) addresses the shortcomings of SR by quantifying the evolutionary connections among the species present in an area. Phylogenetic endemism (PE) addresses the shortcomings of WE and represents the ranges of the branches of the evolutionary tree connecting the species in an area. Australia, with its advanced digitization of spatial reference data is the best model system for quantitative studies of biodiversity at present. I created a phylogeny for the 39 indigenous Australian conifer species using matK and rbcL sequences from GenBank and sequencing the 4 species for which there were no existing data. I used spatial data from Australia’s Virtual Herbarium and removed records of conifers that were not naturally-occurring. I then used Biodiverse v 0.17 to calculate PD, PE and two derived metrics, Relative Phylogenetic Diversity (RPD) and Relative Phylogenetic Endemism (RPE). These metrics identify regions with statistically significantly high or low levels of PD and PE based on randomization tests. The results show that conifer RPD is significantly low on the Northeast coast of Australia, although conifer PD is high in the same region. RPE is significantly high along the Northeast coast, in the same region that RPD is low. Most of these regions are currently encompassed by legally protected Australian Reserves. More precise estimates of biodiversity can be used by conservation policy-makers.

Macrozoobenthos Soft Soils of the Far Eastern Marine Biosphere Reserve

This study analyzed the composition and distribution of the macrozoobenthos of the soft soils of the Far Eastern Marine Biosphere Reserve. Found 176 species, classified in six groups: Polychaeta, Bivalvia, Gastropoda, Cumacea, Isopoda, Echinodermata. The greatest variety of typical for polychaete worms (67 species) and bivalves (48 species). Found that the coefficient of variation in the ratio of the number of major taxonomic groups for soft ground of sublittoral reserve (1.02) is slightly higher than for water areas with domination of the soft soils in northern latitudes (area of Spitsbergen and the North Sea), and is closer to that of the bays and coves of the South China Sea and the North-East coast of Australia.

Soft soil foundation improved by vacuum and surcharge loading

The Pacific Highway has been upgraded to support the high transportation demand between Sydney and Brisbane, along the north-east coast of Australia. To avoid the traffic through the busy town of Ballina, a bypass route was designed to traverse on a floodplain consisting of very soft, highly compressible, saturated marine clays up to 30 m deep in certain locations. A vacuum-assisted surcharge load scheme in conjunction with prefabricated vertical drains was selected to reduce the required time to consolidate the deep subsoil layers. The design of the combined vacuum and surcharge fill system and the construction of the embankment are described, and a comparison of the performance between the combined vacuum and surcharge loading system with the conventional surcharge only system is highlighted. Field data are presented and interpreted to demonstrate how the embankments performed during construction in both vacuum and non-vacuum areas. Suitable design charts for vertical drains are presented and discussed with a worked example, considering both vertical and radial drainage.

Trends in annual CPUE and evidence of sex and size segregation of Sphyrna lewini: Management implications in coastal waters of northeastern Australia

Hammerhead sharks have experienced a drastic global reduction in abundance, yet limited data exist on their general biology and population structure. We use generalised linear models (GLMs) to analyse historical mesh net and drumline catches (1996–2006) of Sphyrna lewini from the Queensland Shark Control Program (QSCP), which covers 10 locations on the north-east coast of Australia. Results show a significant decline in S. lewini female total length over the study period and a significant increase in annual CPUE on the Gold Coast. Sexual segregation was found in Cairns, where S. lewini males were most abundant. A positive linear relationship was found between maternal total length and litter size. Birth-size embryos were found in most months. However, normal birth size (0.50 m) embryos were found in pregnant females most often during spring and summer. Mesh nets were more selective for smaller S. lewini than drumlines. It is recognised that species selectivity of other, more potentially dangerous shark species varies between gear types, but replacement of mesh nets with drumlines would reduce the catch of smaller individuals of S. lewini and assist in their conservation.

Sand beach ridges record 6000 year history of extreme tropical cyclone activity in northeastern Australia

Sand beach ridges are considered to be derived either from aeolian processes and/or waves but their deposition by individual or multiple storms has not been investigated in any detail. We use numerical meteorological and oceanographic models to determine the origin of a sequence of 29 shore parallel sand beach ridges in northeastern Australia. The results suggest that the ridges were constructed by waves and that the final form or height of the ridges is a function of high-energy tropical cyclone generated waves plus storm tides. Hence these landforms archive a nearly 6000 year long history of intense tropical cyclones. The record implies that these extreme tempests occur considerably more frequently than that suggested by the short historical record for this region. The genesis of this sand beach ridge plain has implications for the interpretation of similar sequences elsewhere along the northeast coast of Australia and in comparable environments globally. If other similar sand beach ridge plains have also been deposited by like processes it stands to reason that these long-term records of high intensity tropical cyclones can be used to ascertain a regional scale risk assessment from this hazard.

The Prevalence of Orofacial Pain and Tooth Fracture (Odontocrexis) Associated with SCUBA Diving

To assess the prevalence of orofacial complications associated with SCUBA (self-contained underwater breathing apparatus) diving. Main outcome measures were prevalence of orofacial pain and odontocrexis. Two hundred divers at four dive centres on the north-east coast of Australia were asked to complete a questionnaire that requested information regarding diving experience and facial pain and dental symptoms experienced during diving. One hundred and twenty-five completed questionnaires were returned (63% response rate). The prevalence of reported orofacial pain was 44%. Twenty-one per cent reported toothache, 27% sinus pain, 16% jaw pain, and 12% other pain. The prevalence of odontocrexis was less than 1%. Less than 1% had lost a filling when diving. No divers reported a crown or bridge being dislodged during diving. Among those who returned questionnaires, orofacial pain in divers was common and odontocrexis was rare.

Real-time environmental monitoring of the Great Barrier Reef

The Great Barrier Reef (GBR) is the largest natural feature on earth, stretching more than 2300 km along the northeast coast of Australia. It contains a diverse array of species and habitats that are threatened by environmental and human impacts. Monitoring environmental changes would give a better understanding of the health of this ecological system. It would also help shape decision-making to ensure this important natural asset is protected into the future. This paper investigates how environmental information can be collected and brought back to the mainland from the GBR. A novel method of using the evaporation duct above the ocean surface to tunnel radio signals beyond the horizon is proposed for the link to the mainland, and the design of a hybrid power supply is also outlined. A monitoring network for use on Davies Reef, approximately 80 km off the coast of northern Queensland, is used as a case study in this paper.

Redescription of Pseudogilquinia pillersi (Southwell, 1929) (Cestoda, Trypanorhyncha) from serranid and lethrinid fishes from New Caledonia and Australia

AbstractPseudogilquinia pillersi (Southwell, 1929), a poorly known species of trypanorhynch, is redescribed from plerocerci collected from Epinephelus coioides (Hamilton, 1922), Epinephelus malabaricus (Bloch et Schneider, 1801) (Serranidae) and Plectropomus laevis (Lacépède, 1801) (Serranidae) off New Caledonia. These were compared with specimens from Lethrinus atkinsoni Seale, 1910 and Lethrinus miniatus (Forster, 1801) (Lethrinidae) off the north-east coast of Australia as well as syntypes from Protonibea diacantha (Lacépède, 1802) from Sri Lanka. Although size differences were found in parts of the scolex as well as in the sizes of the tentacular hooks, the hook arrangements were identical in all specimens. The differences observed were attributed provisionally to intra-specific variation across a wide geographic and host range.

Improving harvesting and transport planning within a sugar value chain

Recent economic pressures have forced the Australian sugar industry to achieve better integration and optimization of the cane harvesting and transport sectors of the value chain. The logistical and economic complexity of the harvesting and transport system was captured through the development of a modelling framework that effectively links several component models that describe the parts of the system. Through engaging in participatory research with representatives of a sugar region located at the north-east coast of Australia, we use this modelling framework to address some key industry issues in rationalizing rail track infrastructure and re-organizing harvesting. These issues were addressed by building component models for the modelling framework in the field of location science, namely the capacitated P-Median problem and spatial clustering. By applying the modelling framework and its component models to the case-study region, we explored a range of scenarios with a net cost reduction of up to AU$2 260 000 per year.

Turtle Riding on the Great Barrier Reef

AbstractTurtle riding was once a popular activity among holidaymakers at the Great Barrier Reef off the northeast coast of Australia. In the first half of the twentieth century. it was a significant way for tourists to engage with living marine life. The turtle breeding season offered tourists an opportunity to see female turtles emerge from the sea and come ashore to nest and lay their eggs. They could also witness emerging hatchlings scuttle from shore to sea. This sea-land-sea transformation facilitated unique forms of human-nonhuman animal interaction and was integral to visitor affection for, and affinity with, sea turtles.

Growth, Survival and Reproductive Performance of Domesticated Australian Stocks of the Giant Tiger Prawn, Penaeus monodon, Reared in Tanks and Raceways

The growth, survival and reproductive performance of domesticated Australian stocks of the giant tiger shrimp Penaeus monodon were evaluated in trials conducted in 1997 and 2003. The 1997 trials assessed the performance of first generation progeny of wild broodstock from the northeast coast of Australia and fourth generation progeny of pond-reared broodstock, which also originated from northeast coast wild stocks. In these trials, growth and survival of the shrimp were assessed when reared for 17 mo in tanks. Reproductive performance of the shrimp was assessed at 14.5 mo and 17 mo. The 2003 trials assessed the performance of first generation progeny of wild broodstock from the Gulf of Carpentaria (north coast of Australia). In these trials, growth and survival of shrimp were assessed when reared for 14 mo in tanks and raceways. Reproductive performance of the shrimp was assessed at 11 mo, 12 mo, and 15 mo. Growth and reproductive performance of the stocks varied between trials, families, ages and rearing systems. The most pronounced differences in growth and reproductive performance were between the 1997 and 2003 trials. At 11 mo of age, the average wet weight of the shrimp in the 2003 trials (females 117.1 ± 5.8 g; males 87.9 ± 7.6 g) was 200% greater than the average wet weight of shrimp in the 1997 trials (females 55.2 ± 6.8 g; males 41.2 ± 3.4 g). The reproductive performance of the shrimp was also higher in the 2003 trials in terms of the percentage of spawnings hatching (52.0% in 1997; 77.1% in 2003) and mean hatch rate (21.5% in 1997; 31.6% in 2003). Differences in the growth and reproductive performance of the tank-reared stocks between years were indicative of significant improvements in the rearing environment, diet and husbandry techniques. Variation in the reproductive performance between families was consistent across rearing environments and at different ages and suggests the potential to improve reproductive performance through genetic selection. Notably, this study identified hatch rates of nauplii from the spawned eggs as a key area for future improvement of domesticated stocks reared in tanks and raceways. Future efforts to improve the growth and reproductive performance of domesticated P. monodon could benefit from integrating incremental improvements to husbandry with genetic selection.