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Understanding species' critical habitat requirements is crucial for effective conservation and management. However, such information can be challenging to obtain, particularly for highly mobile, wide-ranging species such as cetaceans. In the absence of systematic surveys, alternative economically viable methods are needed, such as the use of data collected from platforms of opportunity, and modelling techniques to predict species distribution in un-surveyed areas. The present study used data collected by ecotourism and other vessels of opportunity to investigate important habitats of a small, poorly studied population of bottlenose dolphins in Port Phillip Bay, south-eastern Australia. Using 16 years of dolphin sighting location data, an ensemble habitat suitability model was built from which physical factors influencing dolphin distribution were identified. Results indicated that important habitats were those areas close to shipping channels and coastlines with these factors primarily influencing the variation in the likelihood of dolphin presence. The relatively good performance of the ensemble model suggests that simple presence-background data may be sufficient for predicting the species distribution where sighting data are limited. However, additional data from the center of Port Phillip Bay is required to further support this contention. Important habitat features identified in the study are likely to relate to favorable foraging conditions for dolphins as they are known to provide feeding, breeding, and spawning habitat for a diverse range of fish and cephalopod prey species. The results of the present study highlight the importance of affordable community-based data collection, such as ecotourism vessels, for obtaining information critical for effective management., Competing Interests: The authors declare that they have no competing interests., (© 2024 Ledwidge et al.)

The majority of humpback whales (Megaptera novaeangliae) undertake an annual migration from high latitude feeding grounds to tropical/subtropical breeding grounds. Suitable calving habitat for this species includes warm (typically 19°C to 28°C), shallow, sheltered waters in tropical and subtropical waters. Here, we investigated occurrence of calving beyond the primary recognised breeding grounds (16° to 24°S) of the east Australian humpback whale population (E1). We examined location, depth (m), and SST (⁰C) associated with newborn observations in Gold Coast Bay, in southern Queensland, Australia from 2013 to 2016. A total of 74 newborns were recorded in the study area, with the majority observed in July and August. These findings may signify that the Gold Coast Bay provides an apparently suitable habitat for calving for this humpback whale population. As the area has not been classified as calving habitat, these findings will assist conservation managers in making informed management decisions regarding this species. [ABSTRACT FROM AUTHOR]

Background: The present paper represented the third installment on the monogenoidean parasites collected during a workshop exploring the diversity of the parasites of fishes in Moreton Bay, Queensland, Australia. Previous reports on monogenoids collected during the workshop included species parasitizing beloniform and gerreid fishes. Purpose: During January 2016, the author, having responsibility for the identification and description of monogenoids, participated in a workshop supported by an Australian Biological Resources Study Grant to Drs. Thomas Cribb and Scott Cutmore, University of Queensland, to explore the diversity of parasites infecting the fishes of Moreton Bay, Queensland, Australia. Methods: Approximately 100 species of marine fishes were necropsied for parasites. Standard procedures for collecting, mounting, drawing, and measuring of monogenoids were employed. Results: A new species of Euryhaliotrema was collected and described from the silver moony Monodactylus argenteus (Monodactylidae) and the first recording of Euryhaliotrema spirotubiforum on the dory snapper Lutjanus fulviflamma and Russell's snapper Lutjanus russellii (both Lutjanidae) in Moreton Bay was reported. Conclusion: The results suggested that the diversity of dactylogyrids off eastern Australia is under estimated in the literature. [ABSTRACT FROM AUTHOR]

Passive acoustic recordings made in Fowlers Bay, South Australia, during the austral winter of 2013–2017 revealed the presence of several sources of underwater sound. Sound sources of biological origin include baleen and toothed whales, fish and shrimp. Physical sources of underwater sound include wind- and rain-driven noises, and underwater sounds of anthropogenic origin were primarily from boats and occasionally from an aircraft. Biological sound sources were commonly recorded within the frequency range of around 25 Hz to nearly 17 kHz, with baleen whales within the range of ~ 25 Hz to 6 kHz, and dolphins at higher frequencies of approximately 2.5–17 kHz. Broadband sounds from physical and anthropogenic sound sources were noticeable at frequencies above ~ 50 Hz. The ambient noise level in Fowlers Bay at frequencies below 100 Hz was relatively low (around 75 dB re 1 µPa2/Hz for the 95% percentile) due to an insignificant contribution of noise from distant shipping. At higher frequencies, the noise level was governed primarily by noise from wind and varied by nearly 30 dB re 1 µPa2/Hz depending on weather conditions, up to around 80 dB re 1 µPa2/Hz for the 95% percentile during periods of strong winds and intense rainfall. [ABSTRACT FROM AUTHOR]

The identification of expedient bivalve tools recovered from archaeological deposits is currently hindered by a lack of analytical frameworks. In order to identify those shell valves which have been used as expedient tools, analysts must be able to identify and distinguish between pre-mortem and post-depositional modifications, and use-wear from tool use. Central to this difficulty is a lack of experimental analogues for comparison with archaeological material. Here, we present an analytical framework for the identification of expedient bivalve tools made from Polymesoda (= Geloina ) coaxans valves recovered from Australian archaeological sites. This analytical framework consists of a series of actualistic experiments designed to determine those variables useful for distinguishing between modifications produced via pre-mortem and post-depositional processes that can damage molluscan shell, and damage produced via use as an expedient tool. Trampling, flaking and scraping experiments and use-wear analysis are used as a reference for comparison with an assemblage of P . coaxans valves recovered from archaeological sites in Princess Charlotte Bay, north Queensland, Australia. We demonstrate that an analytical framework consisting of an analysis of shell area loss, shell fracture paths, and use-wear can be successfully applied to archaeological samples to confidently distinguish between those valves which have been used as expedient tools, and those which have not. This research has wider implications for the identification of this often overlooked class of shell tools from archaeological sites in Australia and other regions, allowing a more comprehensive understanding of the place of shell tools in coastal economies of the past. [ABSTRACT FROM AUTHOR]

Integration of morphological and molecular approaches to species delineation has become an essential part of digenean trematode taxonomy, particularly when delimiting cryptic species. Here, we use an integrated approach to distinguish and describe two morphologically cryptic species of Hysterolecitha Linton, 1910 (Trematoda: Lecithasteridae) from fishes of Moreton Bay, Queensland, Australia. Morphological analyses of Hysterolecitha specimens from six fish species demonstrated a complete overlap in morphometric data with no reliable differences in their gross morphological characters that suggested the presence of more than one species. Distinctions in ITS2 rDNA and cox1 mtDNA sequence data for corresponding specimens suggested the presence of two forms. A principal component analysis on an imputed dataset showed clear separation between the two forms. These two forms are partially separated on the basis of their host's identity. Therefore, we describe two morphologically cryptic species: Hysterolecitha melae n. sp. from three species of Abudefduf Forsskål and one species of Parma Günther (Pomacentridae), with the Bengal sergeant, Abudefduf bengalensis (Bloch), as the type-host; and Hysterolecitha phisoni n. sp. from species of Pomacentridae (including A. bengalensis), Pomatomidae and Siganidae, with the black rabbitfish, Siganus fuscescens (Houttuyn), as the type-host., (© 2023. The Author(s).)

Background: Global increases in opioid prescribing and misuse have prompted calls for closer regulation. Opioid prescription following surgery may lead to long term opioid use. A study was conducted evaluating opioid prescriptions on hospital discharge following common general surgery operations in the Bay of Plenty., Methods: Retrospective observational study over a two-year period in two regional New Zealand hospitals. Six hundred and eleven patients aged 18-64 years were assessed. Patients with complications, readmission, and a prescription of opioids in the preceding 3 months were excluded., Results: A total of 460 patients (165 Laparoscopic Cholecystectomy (LC), 200 Laparoscopic Appendicectomy (LA) and 95 Open Inguinal Hernia Repair (OIHR)) were included in analysis. Opioids were prescribed to 53% of LC, 55% of LA, and 60% of OIHR patients, with a mean of 75.8 Morphine Milligram Equivalents (MMEs), 75.3 MMEs, and 82.8 MMEs respectively. Seven percent of patients (18/254) received a second opioid prescription within 3 months, and of those only 1.6% (4/254) received a further prescription between 3 and 6 months from discharge. Opioid prescribing did not correlate with operation, ethnicity, age, length of stay, or gender, except for males receiving a more MMEs than females following LC (mean 102.0 MMEs versus 65.4 MMEs, P = 0.017)., Conclusion: This study shows a rate of opioid prescribing lower than the USA, and greater than seen in an Australian setting. Substantial amounts of opioids were prescribed following uncomplicated surgery, with significant variability. Improvements in training in post-operative opioid prescribing are needed. Fortunately, rates of ongoing opioid use were low., (© 2023 Royal Australasian College of Surgeons.)

Understanding processes that govern the transport and distribution of terrestrial sediments to and within bays is critical for interpreting the drivers of long-term changes in these ecosystems. On the east coast of Australia increased soil erosion and sediment delivery following extensive land clearing in the contributing catchments, associated with European settlement, is highlighted as a key driver of the decline of numerous nearshore habitats including seagrass meadows and in-shore coral reefs. Here we use optical, radiocarbon and radionuclide dating to estimate mass accumulation rates and type of terrestrial sedimentation in central Moreton Bay during the Holocene. We compare the long-term rates of infilling within the central basin with the recent past and show a 3–9 fold increase in sediment accretion over the last 100 years compared to the long term (last ∼ 1500 to 3000 yrs) average. Infilling during the Holocene is not spatially uniform, with preferential deposition occurring within the now submerged palaeochannels of the Brisbane and Pine rivers. We suggest that modern turbidity regimes in Moreton Bay are the result of the compounded effect of both a historical increase in fine sediment supply and a rapid decline in the effective storage capacity of the basin. [ABSTRACT FROM AUTHOR]

Twenty-nine dactylogyrid species were reported from teleosts collected during a survey of the parasites of fishes of Moreton Bay, Queensland, Australia, in 2016. Two new genera, Ecnomotrema n. gen. and Pleuronectitrema n. gen., were proposed, and 13 new species were illustrated and described: Atherinicus difficilis n. sp., Diversohamulus similis n. sp., and Ecnomotrema cetiosum n. sp. from Atherinomorus vaigiensis; Haliotrema apiculum n. sp. from Pempheris schwenkii; Haliotrema tugulduriforme n. sp. from Scarus ghobban; Lethrinitrema australiense n. sp., and Lethrinitrema lituus n. sp. from Lethrinus nebulosus; Tetrancistrum siganioides n. sp. from Siganus fuscescens; Ligophorus bostrychus n. sp. from Planiliza subviridis; Neohaliotrema gemmula n. sp. from Abudefduf vaigiensis; Neohaliotrema moretonense n. sp. from Ab. vaigiensis and Ab. bengalensis; and Pleuronectitrema spirula n. sp. from Pseudorhombus arsius (all from Moreton Bay); Pleuronectitrema kuwaitense Kritsky & Sey n. sp. was described from specimens collected from P. arsius in Kuwait during 1996. Ten new host records were recorded: Chauhanellus duriensis Lim, 1994 and Hamatopeduncularia thalassini Bychowsky & Nagibina, 1969 from Pararius proximus; Diplectanotrema sp. 1 and sp. 2 from Sillago maculata and Goniistius vestitus, respectively; Diversohamulus tricuspidatus Bychowsky & Nagibina, 1969 from At. vaigiensis; Hal. cf. dempsteri (Mizelle & Price, 1964) Young, 1968 from Prionurus microlepidotus; Hal. spirale Yamaguti, 1968 from Upeneus tragula; Ligophorus kaohsianghsieni (Gussev, 1962) Gussev, 1985 from Planiliza subviridis; and Neohaliotrema malayense Lim & Gibson, 2010 from Ab. bengalensis and Ab. whitleyi. Twenty-five new faunal records for Moreton Bay were recorded, including the new species listed above and C. duriensis, Diplectanotrema sp. 1 and sp. 2, Diversohamulus tricuspidatus Bychowsky & Nagibina, 1969, Glyphidohaptor phractophallus Kritsky, Galli, & Yang, 2007, Hal. cf. dempsteri, Hal. johnstoni Bychowsky & Nagibina, 1970, Hal. spirale, Yamaguti, 1968 Hamatopeduncularia thalassini Bychowsky & Nagibina, 1969, Lethrinitrema nebulosum Sun, Li, & Yang, 2014, Ligophorus kaohsianghsieni (Gussev, 1962) Gussev, 1985, Ligophorus parvicopulatrix Soo & Lim, 2012, and Neohaliotrema malayense Lim & Gibson, 2010. Three new combinations were proposed: Hal. spariense Roubal, 1981 as Euryhaliotrema spariense (Roubal, 1981) n. comb.; and Hal. arsiosa Venkatanarasaiah, 1984 and Hal. youngi Venkatanarasaiah, 1984 as Pleuronectitrema arsiosa (Venkatanarasaiah, 1984) n. comb. and Pleuronectitrema youngi (Venkatanarasaiah, 1984) n. comb., respectively; Haliotrema sp. of Zhang is transferred to Pleuronectitrema as Pleuronectitrema sp. Hal. ctenochaeti Yamaguti, 1968 was replaced with Hal. asymphylum n. nom. to remove it from homonymy with Hal. ctenochaeti Young, 1968. Pseudohaliotrematoides zancli Yamaguti, 1968 was transferred to Haliotrema as Haliotrema hawaiiense n. nom. Hal. zancli Yamaguti, 1968 was considered a junior subjective synonym of Hal. dempsteri., (© A.L. Silva et al., published by EDP Sciences, 2023.)

Dietary analysis was conducted on juveniles of 10 numerically abundant fish species inhabiting tropical seagrass beds in North Queensland, Australia. Gammarid amphipods were consumed by all of the species, but their contribution to the diet of each varied. Crab larvae and copepods contributed to the diets ofLeiognathus bindus,Pranesus endrachtensisandStolephorussp.; polychaetes and isopods were consumed bySillago maculata burrus,Lethrinussp.,Pelates sexlineatusandSiganus canaliculatus; andFavonigobius reichei,Coris caudimaculaandArothron manilensisfed on bivalves. Seagrass and gastropods were rarely ingested by most of these fishes, but made a moderate contribution to the diet ofA. manilensis.With the exception ofL. bindus, the diet of each species was correlated with size: smaller species consumed copepods, crab larvae and gammarid amphipods, while larger species ate polychaetes, bivalves, isopods and gastropods. Non-metric multidimensional scaling (MDS) ordination plots emphasised the variation in dietary composition between species, and showed that this was often correlated with mouth length and width of the fish—for example, species with larger mouth dimensions tended to have broader diets. These interspecific differences in dietary composition increase the number of food resources available to these fishes, thereby reducing the potential competition for resources within the fish community. [ABSTRACT FROM PUBLISHER]

The temperate seascapes of southern Australia have, until recently, received less conservation attention than the country's tropical waters. Here, we describe the results of an expert elicitation aimed at identifying gaps and opportunities in marine conservation for temperate waters. The process highlighted the need for focusing conservation attention on temperate bays, estuaries and inlets. The subsequent development of the Great Southern Seascapes program by The Nature Conservancy is aimed at beginning to address this need. The program focuses on the following actions for temperate Australian bays, estuaries and inlets: (a) increased protection, (b) ‘in the water’ restoration, (c) initiatives to address sea-level rise, (d) improved management and increased stakeholder involvement, (e) science and monitoring, and (f) community, government, and corporate engagement and funding. Actions taken to date, including commencing Australia's first ever oyster reef restoration project, and future directions, are outlined. [ABSTRACT FROM PUBLISHER]

Kämpf, J. and Ellis, H., 2015. Hydrodynamics and flushing of Coffin Bay, South Australia: A small tidal inverse estuary of interconnected bays. Using a three-dimensional hydrodynamic model and the concept of water age, this study explores the hydrodynamics and flushing characteristics of Coffin Bay, South Australia, which is a small inverse estuary of interconnected bays. Model findings suggest that the estuary is mainly tidally flushed throughout the year. Despite the existence of strong tidal flows >1 m/s in passages between bays of the estuary, the resultant tidal stirring zones are largely disconnected from each other. This disconnection induces a relatively slow flushing of the estuary's inner bays, where maximum water ages are 80-100 days. Given the tidal dominance in the flushing dynamics, a simple diffusion equation based on a total effective transverse diffusivity D (estimated from the model predictions) can be used to describe the flushing behaviour of the estuary. This equation is applied to derive the thermal response of Coffin Bay to either temperature variations in ambient shelf water or changes in surface heat fluxes. Findings indicate that, on timescales of 30 days, the inner bays of Coffin Bay respond predominantly to changes in surface heat fluxes, whereas the outer bay is more responsive to temperature variations in ambient shelf water. We quantify these individual responses in terms of spatially variable 'thermal response factors,' which are fundamental properties inherent in the estuary's flushing dynamics. [ABSTRACT FROM AUTHOR]

The disposal of untreated urban and industrial wastewater has a deleterious effect on both the water and sediment quality of Oyster Bay located in south Sydney, Australia. The present investigation was undertaken to evaluate the potential pollution of marine sediments in Oyster Bay. The results of metals were compared with adverse biological effect values effect range low (ERL) and effect range median (ERM). Spatial distribution of trace metals was estimated by applying geographic information system. The results indicated that the sediments were polluted with Cu, Zn, As and Pb, which exceeded ERL levels. However, these metals were still below ERM values, and other metals Cr and Ni were below ERL. Moreover, the highest concentrations of metals were around discharge points and in the inner bay. Further, trace metals could be attributed to human activities within the bay as they declined in concentrations with increasing sediment depth. [ABSTRACT FROM AUTHOR]

Highlights: [•] This is the most detailed examination of heavy metals in Deception Bay since 1975. [•] XRF and various pollution indices were used to determine sediment quality. [•] There is ample evidence of lead contamination and enrichment of other heavy metals. [•] Multivariate data analysis gave insights into the underlying structure in the data. [•] The results have implications for pollution in complex marine environments. [ABSTRACT FROM AUTHOR]

Two species of Bychowskicotylidae (Monogenoidea: Gastrocotylinea) were collected from the gills of the sweetlips Diagramma labiosum Macleay (Haemulidae) obtained from Moreton Bay, Queensland, Australia, during January 2016. Lebedevia n. gen. is proposed for bychowskicotylids having 1) a bilaterally symmetrical haptor with four pairs of gastrocotylid-like clamps and lacking an armed lappet (anchors and hooks absent); 2) longitudinal sclerotized internal ridges lining the vas deferens, 3) an unarmed male copulatory organ, and 4) four interconnected vesicles located posterior to the genital atrium and lying on the body midline dorsal to the uterus and ventral to the vas deferens. Lebedevia lebedevi n. sp., the type and only species of the genus, is described, and Tonkinopsis transfretanus Lebedev, 1972 is recorded for the first time in Moreton Bay. Yamaguticotyla Price, 1959 (Bychowskicotylidae) is considered nomen nudum, and the authorship of the genus is corrected to Yamaguticotyla Yamaguti, 1963., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Two species of Anomalocaris co-occur in the Emu Bay Shale ( Cambrian Series 2, Stage 4) at Big Gully, Kangaroo Island. Frontal appendages of Anomalocaris briggsi Nedin, 1995, are more common than those of Anomalocaris cf. canadensis Whiteaves, 1892, at a quarry inland of the wave-cut platform site from which these species were originally described. An oral cone has the three large, node-bearing plates recently documented for Anomalocaris canadensis, confirming that Anomalocaris lacks a tetraradial ' Peytoia' oral cone and strengthening the case for the identity of the Australian specimens as Anomalocaris. Disarticulated anomalocaridid body flaps are more numerous in the Emu Bay Shale than in other localities, and they preserve anatomical details not recognized elsewhere. Transverse lines on the anterior part of the flaps, interpreted as strengthening rays or veins in previous descriptions of anomalocaridids, are associated with internal structures consisting of a series of well-bounded, striated blocks or bars. Their structure is consistent with a structural function imparting strength to the body flaps. Setal structures consisting of a series of lanceolate blades are similar to those of other anomalocaridids and are found in isolation or associated with body flaps. A single specimen also preserves putative gut diverticula. The morphology of the appendages, oral cone, gut diverticula and compound eyes of Anomalocaris, along with its large size, suggests that it was an active predator, and specimens of coprolites containing trilobite fragments and trilobites with prominent injuries have been cited as evidence of anomalocaridid predation on trilobites. Based on frontal appendage morphology, Anomalocaris briggsi is inferred to have been a predator of soft-bodied animals exclusively and only Anomalocaris cf. canadensis may have been capable of durophagous predation on trilobites, although predation (including possible cannibalism) by Redlichia could also explain the coprolites and damage to trilobite exoskeletons found in the Emu Bay Shale. [ABSTRACT FROM AUTHOR]

The article discusses the voyage of the immigrant clipper ship "Queen of the Colonies" from England to Moreton Bay in Brisbane, Queensland in 1862 and 1863. It examines the the diary of passenger Henry John Ford, an engagement with the Confederate States of America raider "CSS Alabama," and the deaths of several passengers, particularly passenger Emma Barnfield, on the "Queen of the Colonies" due to the measles and other maladies. The article also discusses the leadership of ship captain R. Cairncross.

Shepherd's beaked whale (Tasmacetus shepherdi) is one of the least known cetaceans. Based on the location of 45 strandings and two at-sea sightings, T. shepherdi is thought to have a circumpolar distribution in the temperate waters of the Southern Hemisphere between latitudes 33°S and 50°S. On 10 November 2008, a female T. shepherdi was found dead on a beach in Shark Bay, Western Australia, at 113° 16'E, 26° 20'S. DNA sequencing was used to verify the identification of the specimen, which is the northern most record for this species. The age of the specimen was estimated to be between 12 and 15 years, based on counting dentine growth layer groups in two teeth, assuming an annual rate of deposition. [ABSTRACT FROM AUTHOR]

Abstract: Permanent boat moorings have contributed to the decline of seagrasses worldwide, prompting the development of ‘seagrass-friendly’ moorings. We contrasted seagrass cover and density (predominantly Posidonia australis) in the vicinity of three mooring types and nearby reference areas lacking moorings in Jervis Bay, Australia. We examined two types of ‘seagrass-friendly’ mooring and a conventional ‘swing’ mooring. ‘Swing’ moorings produced significant seagrass scour, denuding patches of ∼9 m radius. Seagrass-friendly ‘cyclone’ moorings produced extensive denuded patches (average radius of ∼18 m). Seagrass-friendly ‘screw’ moorings, conversely, had similar seagrass cover to nearby reference areas. Our findings reinforce previous work highlighting the negative effects of ‘swing’ and ‘cyclone’ moorings. In contrast, the previously unstudied ‘screw’ moorings were highly effective. We conclude that regular maintenance of moorings and the monitoring of surrounding seagrass are required to ensure that ‘seagrass-friendly’ moorings are operating effectively. This is important, as following damage Posidonia will take many decades to recover. [Copyright &y& Elsevier]

We report four new species of monorchiids infecting teleost fishes from Australian waters. Two new species of Paralasiotocus Wee, Cutmore, Pérez-del-Olmo & Cribb, 2020, Pa. abstrusus n. sp. and Pa. tectus n. sp., are described from haemulids of the Great Barrier Reef. The two species are morphologically cryptic and occur in sympatry but differ significantly in cox1 mtDNA and ITS2 rDNA sequence data. Paralasiotocus tectus n. sp. is found only in Plectorhinchus albovittatus (Rüppell) whereas Pa. abstrusus n. sp. infects Pl. albovittatus, Plectorhinchus flavomaculatus (Cuvier) and Plectorhinchus lineatus (Linnaeus). The two species differ from all known species of Paralasiotocus in the possession of a clear gap in the spines of the terminal organ. A new species is described from a mullid, Parupeneus spilurus (Bleeker), from off Heron Island and Moreton Bay. The new species is morphologically broadly consistent with the concept of Paralasiotocus in the possession of an unspined genital atrium, bipartite terminal organ, and lobed ovary. However, it possesses a highly lobed cirrus and is phylogenetically widely separated from the two species of Paralasiotocus characterized here, and thus we propose Lobucirruatus infloresco n. g., n. sp. Proctotrema prominens n. sp., is described from Pl. albovittatus. It is differentiated from all other species of Proctotrema in the combination of a prominent metraterm, slightly fusiform body, slightly funnel-shaped oral sucker, elongate cirrus-sac, unlobed ovary, and caeca that terminate in the post-testicular region., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Abstract: The distribution, nature and extent of microbial deposits in Hamelin Pool, Shark Bay have been investigated and mapped with emphasis on the occurrence, external morphologies, internal fabrics, constructional mechanisms, microbial communities, growth rates and sediment associations in the intertidal and previously little researched subtidal zone. Detailed georeferenced substrate mapping revealed extensive subtidal microbial deposits occupying approximately 300km2 of the total Holocene 1400km2 area of Hamelin Pool. The Microbial Pavement covers 227km2 of the subtidal substrate that together with columnar structures reveals a subtidal microbial habitat which occupies an area 10 times larger than the area of the intertidal deposits. Microbial carbonate is composed of aragonite (80–98%) that reveals high positive values of δ13C (+4.46 to +5.88) and δ18O (+3.06 to +3.88) as a characteristic of the highly evaporative environment with extensive microbial activity. Oldest dated heads are 1915 and 1680 14Cyears BP, and the overall system was deposited in two stages; the first between 2000 and 1200 and the last from 900years BP to the present. Slow growth rates vary from less than 0.1mm/year to 0.5mm/year. Different internal fabrics were constructed according to their position in relation to the littoral zone by distinct microbial communities, and lateral fabric relations have been established. Evidence of shallowing-upward fabric sequences of microbial origin reflects relative falling sea levels during the late Holocene and is likely useful in ancient environmental interpretation. A sequence of events and mechanisms are described emphasizing differences between the stromatolitic, thrombolitic and cryptomicrobial deposits in Shark Bay. The new substrate map and depositional history for this distinctive and peculiar microbial habitat establish the significance of subtidal structures and emphasize the geoscientific importance of Hamelin Pool, especially with respect to early life studies and ancient analogues for understanding microbial activity, deposit characteristics, fenestral fabrics and distribution. [Copyright &y& Elsevier]

Human activities in coastal areas frequently cause loss of benthic macrophytes (e.g. seagrasses) and concomitant increases in microalgal production through eutrophication. Whether such changes translate into shifts in the composition of sediment detritus is largely unknown, yet such changes could impact the role these ecosystems play in sequestrating CO2. We reconstructed the sedimentary records of cores taken from two sites within Botany Bay, Sydney - the site of European settlement of Australia - to look for human-induced changes in dominant sources of detritus in this estuary. Cores covered a period from the present day back to the middle Holocene (~6000 years) according to 210Pb profiles and radiocarbon ( 14C) dating. Depositional histories at both sites could not be characterized by a linear sedimentation rate; sedimentation rates in the last 30-50 years were considerably higher than during the rest of the Holocene. C : N ratios declined and began to exhibit a microalgal source signature from around the time of European settlement, which could be explained by increased nutrient flows into the Bay caused by anthropogenic activity. Analysis of stable isotopic ratios of 12C/ 13C showed that the relative contribution of seagrass and C3 terrestrial plants (mangroves, saltmarsh) to detritus declined around the time of rapid industrial expansion (~1950s), coinciding with an increase in the contribution of microalgal sources. We conclude that the relative contribution of microalgae to detritus has increased within Botany Bay, and that this shift is the sign of increased industrialization and concomitant eutrophication. Given the lower carbon burial efficiencies of microalgae (~0.1%) relative to seagrasses and C3 terrestrial plants (up to 10%), such changes represent a substantial weakening of the carbon sink potential of Botany Bay - this occurrence is likely to be common to human-impacted estuaries, and has consequences for the role these systems play in helping to mitigate climate change. [ABSTRACT FROM AUTHOR]

A numerical model is used to investigate the resonances of the Gulf of Carpentaria and the Arafura Sea. The model is forced at the shelf edge, first with physically realistic real values of angular velocity. The response functions at points within the region show maxima and other behaviour which imply that resonances are involved but it is difficult to be more specific. The study is then extended to complex angular velocities and the results then show a clear pattern of gravity wave and Rossby wave like resonances. The properties of the resonances are investigated and used to reinterpret the responses at real values of angular velocity. It is found that in some regions the response is dominated by modes trapped between the shelf edge and the coast or between opposing coastlines. In other regions the resonances show cooperative behaviour, possibly indicating the importance of other physical processes. [ABSTRACT FROM AUTHOR]

This paper investigates bar migration in a fetch limited strong wind bay (Seaford Beach SE Australia). Onshore bar migration on open ocean beaches is dependant on long period swell wave and occurs during low energy conditions. However, in a fetch limited environment such waves are absent and most studies suggest that during low energy conditions the beach remains in an arrested state (Jackson et al. 2002). This paper spans a three month study period (15th March - 8th June 2008). Measurement of near shore morphology and wind data were collected. The two bars at Seaford behaved very differently; both onshore and offshore migration was detected during the three recorded storm events. The paper found that, firstly, wave breaking was incomplete in the middle bar during event 1 - the inner bar migrated offshore. Secondly wave breaking in the middle bar was almost complete during event 2 and the inner bar migrated onshore. Thirdly when wave breaking was complete in the middle bar during event 3 - the inner bar remained arrested on some profiles but bar height increased on others. The wave steepness threshold for onshore migration of the inner bar was parameterized s 0.041 - 0.042. Beach sediment modeling in fetch limited strong wind bays remains understudied. Our results should help to improve the predictive capability of beach sediment budgets in fetch limited strong wind bays. [ABSTRACT FROM AUTHOR]

Occupation on the coastal margins of northern Australia over the mid to late Holocene characteristically reflects chronological and spatial variability in settlement and subsistence. In many geographically diverse regions across the tropical coast, the archaeological record indicates patterns of molluscan resource exploitation that reflects the altered local ecological habitats that accompanied broader coastal environmental change over the last few thousand years. This paper investigates these issues via analyses of molluscan species richness, diversity, and habitat exploitation through time and space on the Point Blane Peninsula, Blue Mud Bay, north-east Arnhem Land. As well as variability in the intensity of exploitation, this research confirms the interpretation of previous investigation of coastal occupation as being flexible and dynamic, with changes linked to alterations in species availability and abundance relative to changes in near-shore environments. [ABSTRACT FROM AUTHOR]

As global climate change drives the demise of tropical reef ecosystems, attention is turning to the suitability of refuge habitat. For the Great Barrier Reef, are there historically stable southern refugia where corals from the north might migrate as climate changes? To address this question, we present a precise chronology of marginal coral reef development from Moreton Bay, southeast Queensland, Australia. Our chronology shows that reef growth was episodic, responding to natural environmental variation throughout the Holocene, and that Moreton Bay was inhospitable to corals for about half of the past 7000 years. The only significant change in coral species composition occurred between ∼200 and ∼50 years ago, following anthropogenic alterations of the bay and its catchments. Natural historical instability of reefs, coupled with environmental degradation since European colonization, suggests that Moreton Bay offers limited potential as refuge habitat for reef species on human time scales. [ABSTRACT FROM AUTHOR]

We monitored numbers of Red Knots (Calidris canutus) staging in Bohai Bay, China (39°02′N, 118°15′E) on northward migration. Knots were identified to subspecies, and we systematically searched for colour-banded birds from the non-breeding grounds. We modelled migratory turnover, and revised estimates of flyway population using recently published counts from the non-breeding grounds. Two Russian-breeding subspecies occurred at our study site: C. c. rogersi(migrating to Chukotka), and C. c. piersmai(migrating to the New Siberian Islands); they co-occur on non-breeding grounds in Australia and New Zealand, but differ markedly in timing of migration. We conservatively estimate that our study site, comprising only 20km of coastline, was used by over 45% of the combined world population of adult C. c. rogersiand C. c. piersmai– a conclusion supported by the independent data on frequency of resighting of colour-banded birds from north-western Australia and New Zealand. Much of this vital staging area is now being destroyed through construction of the Caofedian Industrial Zone and more westerly developments, which comprise only some of the many tidal flat ‘reclamation’ projects in the region. Preservation of the remaining tidal flats of Bohai Bay is essential to the conservation of Red Knots in the East Asian–Australasian Flyway. [ABSTRACT FROM AUTHOR]

Several types of equations have been proposed in the past 30 years to describe the planform of crenulate-shaped bays in static equilibrium: a logarithmic spiral, a parabolic curve, a hyperbolic tangent curve, and a set of circle arcs. Although several authors pointed out that these models have some physical and mathematical weaknesses, they find much use in practical applications, particularly the parabolic form. Several expressions of the parabolic shape have been proposed. Hsu and Evans’ original ones fit best the experimental values of Ho’s model tests and of Australian bays in equilibrium used to determine these expressions. The formula proposed by Tan and Chiew respects the tangent condition of the incident wave crest line at the control point and the crossing of the beach line through this point. The expression proposed in Italy by Mita also respects the conditions on the critical angle of a bay in equilibrium, as experimentally determined by Hsu and Silvester; but it poorly fits the data of Ho’s model tests and of Australian bays in equilibrium. This article proposes a new cubic equation to describe crenulate-shaped bays in static equilibrium. The proposed relationship includes the advantages of the three parabolic expressions mentioned above. In fact this proposed third-order equation interpolates the experimental data used by Hsu and Evans to the same degree of approximation as in their original second-order relationship. It also rigorously respects the theoretical conditions at the control point on the downdrift beach line as well as the condition of the critical angle experimentally determined by Hsu and Silvester. Finally the indentation ratio values proposed by Silvester and Hsu for bays in equilibrium are well approximated by the cubic equation across the whole application range. In short, the current formalism is mathematically inconsistent and the proposed modification resolves this as a relatively straightforward amendment of the formulas which leads to moderate changes in the results of the shoreline, but reduces some of the errors in the process of applying this type of model in engineering practice. [ABSTRACT FROM AUTHOR]

The climate along the subtropical east coast of Australia is changing significantly. Rainfall has decreased by about 50mm per decade and temperature increased by about 0.1°C per decade during the last 50years. These changes are likely to impact upon episodes of hypersalinity and the persistence of inverse circulations, which are often characteristic features of the coastal zone in the subtropics and are controlled by the balance between evaporation, precipitation, and freshwater discharge. In this study, observations and results from a general ocean circulation model are used to investigate how current climate trends have impacted upon the physical characteristics of the Hervey Bay, Australia. During the last two decades, mean precipitation in Hervey Bay deviates by 13% from the climatology (1941–2000). In the same time, the river discharge is reduced by 23%. In direct consequence, the frequency of hypersaline and inverse conditions has increased. Moreover, the salinity flux out of the bay has increased and the evaporation induced residual circulation has accelerated. Contrary to the drying trend, the occurrence of severe rainfalls, associated with floods, leads to short-term fluctuations in the salinity. These freshwater discharge events are used to estimate a typical response time for the bay. [Copyright &y& Elsevier]

Abstract: Hybrid processes combining fibre filter with deep bed filtration process such as (i) fibre filter and sand filter, (ii) fibre filter and anthracite and (iii) fibre filter and dual media filter were investigated as pre- treatments to SWRO. Seawater was drawn from Chowder Bay, Sydney. The effect of different pretreatment hybrid systems was investigated in terms of silt density index (SDI10), modified fouling index (MFI), headloss across the filters and reduction in turbidity and dissolved organic carbon (DOC). The in-line flocculation in fibre filter improved the performance of the pretreatment hybrid system as measured by the MFI, SDI10, headloss, turbidity and DOC removal. The lowest SDI10 and MFIwere found with a fibre filter operated at a filtration velocity of 40 m/h followed by dual media filter operated at a filtration velocity of 5 m/h. The lowest headloss and turbidity was found with a fibre filter operated at a filtration velocity of 40 m/hr followed by anthracite operated at a filtration velocity of 5 m/h. This system also gave an effluent with the lowest DOC of 0.64 mg/L corresponding to a removal efficiency of about 70%. [Copyright &y& Elsevier]

Abstract: Erosion of the southern Gold Coast beaches (SE Queensland, Australia) was exacerbated after the extension of the Tweed River training walls in the early 1960s. To achieve the objective of restoring and maintaining beach amenity, significant nourishment works have been undertaken in Coolangatta Bay over the past 30 years. Particularly, under the Tweed River Entrance Sand Bypassing Project (TRESBP) since 1995, a number of nourishment campaigns and the implementation of a permanent sand bypass system in 2001 have resulted in significant changes of Coolangatta Bay morphology. The present case study investigates the influence of both wave climate and nourishment works on the area extending from the updrift Snapper Rocks area to downdrift Kirra Beach. SWAN spectral wave model is implemented at Coolangatta Bay area and forced by the global wave model WW3 to estimate wave forcing and the potential natural longshore drift entering in Coolangatta. Specific transects extracted from accurate bathymetric surveys are used to investigate and quantify Coolangatta Bay sedimentation for the period 1987–2005. A network of Argus video stations provides high sample rate information on the shoreline evolution. Results show that, over the past 10 years, Coolangatta Bay has infilled rapidly. Sedimentation reached up to 6 m in some areas between 1995 and 2005, with beach width increasing by 200 m at Kirra Beach. Rapid seaward shoreline migration is consistent with the intense over-pumping of sand relative to the natural potential to move sand alongshore. The nourishment strategy used during this project has successfully delivered large amounts of sand to the southern Gold Coast embayment, although it has been up to now controversial from many community perspectives. The artificial sand bypassing process proved to be much more efficient than depositing the dredged sand in the nearshore area which requires a significant period of low energy condition in order for the deposited sediment to migrate shoreward and weld to the shore. This case study confirms that, when carefully undertaken, sand bypassing is a sustainable and flexible soft engineering approach which can work in concert with natural processes. [Copyright &y& Elsevier]

Use of multiple observers in large-scale bird surveys is often unavoidable. But how significant are observer differences in bird detection? Do observer effects significantly influence inferences about environmental factors on birds? We conducted a field experiment to quantify differences between observers in the detection of birds at Booderee National Park, south-eastern Australia. We also re-analysed a large dataset from an observational study where multiple observers had participated in bird surveys. We identified highly significant observer differences for estimates of bird species richness and the probability of detection of three exemplar taxa. We demonstrated that observer effects would not substantially alter inferences we made about relationships between bird species and vegetation type or burning history. We believe that four features of our survey design and protocol limited the magnitude of observer effects on environmental inferences: (1) high levels of replication of classes of field sites – critical for relative comparisons of site (vegetation) types; (2) pre-survey screening to ensure that only experienced ornithologists participated in surveys; (3) repeat sampling of field sites by a different observer on a different day to reduce the impacts of observer heterogeneity and ‘day' effects; and (4) precluding surveys during poor weather or long after dawn, also to limit ‘day' effects. [ABSTRACT FROM AUTHOR]

Measurements of the surf zone wave field and morphology were obtained from a multi-barred beach in a fetch-limited, strong-wind bay (Seaford, southeastern Australia) during both low- and high-energy conditions. Analysis of the infragravity energy present during high-energy events (onshore winds >7 ms−1) revealed that it was broad-banded, consisting of a mixture of standing and progressive motions and displaying daily variations in standing wave length scales. Infragravity standing waves were therefore not considered significant to the formation and migration of bars at Seaford during this study, with bar behaviour during high energy events potentially attributable to either breaking wave-bed return flow and/or self-organisational mechanisms. [ABSTRACT FROM AUTHOR]

A new species of Paravargula is described from Princess Charlotte Bay, northeastern Australia. Members of the genus are widespread in the Indian and Pacific Oceans, but the genus was not previously known from Australia. The genus is divided into the HIRSUTA and ARBOREA Groups and a key is presented to the species in the latter group, which contains Paravargula karenae, new species. [ABSTRACT FROM AUTHOR]

During 30 days in May and June 2003, the R/V Southern Surveyor was operating in the Gulf of Carpentaria, northern Australia. Measurements of sea surface temperature (SST) were made with an accurate single-channel infrared radiometer as well as with the ship’s thermosalinograph. These ship-based measurements have been used to assess the quality of the SST derived from nine satellite-borne instruments. The satellite dataset compiled during this period also allows the intercomparison of satellite-derived SST fields in areas not covered by the ship’s track. An assessment of the SST quality from each satellite instrument is presented, and suggestions for blending ground and satellite measurements into a single product are made. These suggestions are directly applicable to the international Global Ocean Data Assimilation Experiment (GODAE) High Resolution SST Pilot Project (GHRSST-PP) that is currently developing an operational system to provide 6-hourly global fields of SST at a spatial resolution close to 10 km. The paper demonstrates how the Diagnostic Datasets (DDSs) and Matchup Database (MDB) of the GHRSST-PP can be used to monitor the quality of individual and blended SST datasets. Recommendations for future satellite missions that are critical to the long-term generation of accurate blended SST datasets are included. [ABSTRACT FROM AUTHOR]

Abstract  Giant Australian cuttlefish form a mass spawning aggregation at a single site in northern Spencer Gulf (NSG) in South Australia every austral winter. Samples of cuttlefish were collected from this region over three consecutive years. Analysis of regular growth increments in the cuttlebones of these individuals, revealed a polymorphism in growth pattern for both sexes. Three distinct “bone patterns” were identified based on the variation in increment widths over the lengths of the bones. All bones analysed conformed to one of the three bone patterns, and the increment width patterns were consistent between years. Interpretation of the patterns, suggested that Sepia apama have two alternative life cycles. The first involves rapid juvenile growth during the first summer after hatching, with maturity reached within 7–8 months. These individuals return to spawn in their first year as small individuals. The second life cycle involves much slower juvenile growth during the first summer, with maturity deferred until their second year, when they return to spawn as much larger individuals. Thus, the age compositions of populations of S. apama in the NSG appear to consist of two year classes for both sexes. [ABSTRACT FROM AUTHOR]

A field study was conducted to investigate sewage inputs at popular anchorages in Moreton Bay, a sub-tropical, semi-enclosed embayment system in Southeast Queensland, Australia. Sterol biomarkers were quantified in sediments revealing low levels over a spatial and temporal scale consistent with a shallow, oligotrophic, highly dynamic, sand dominated system. Despite low concentrations (ng/g) and high variability, relevant sterol/stanol pairs remained well-correlated and were successful in identifying an unexpected once-off pollution event from a point source at Moreton Bay Island. During this incident, the main human sewage biomarker, coprostanol, was found at a concentration of 1.4 μg/g, with a coprostanol/5α-cholestanol ratio of 3.2. Other than this one incident, sterol levels were consistently low even when anchorages were at full capacity. Thus, sewage from recreational vessels was found to have very little effect on sediment quality at anchorages in Moreton Bay and Gold Coast Broadwater. [ABSTRACT FROM AUTHOR]

Guichen Bay on the south-east coast of South Australia faces west towards the prevailing westerly winds of the Southern Ocean. The bay is backed by a 4 km wide Holocene beach-ridge plain with more than 100 beach ridges. The morphology of the Guichen Bay strandplain complex shows changes in the width, length, height and orientation of beach ridges. A combination of geomorphological interpretation, shallow geophysics and existing geochronology is used to interpret the Holocene fill of Guichen Bay. Six sets of beach ridges are identified from the interpretation of orthorectified aerial photographs. The ridge sets are distinguished on the basis of beach-ridge orientation and continuity. A 2·25 km ground-penetrating radar (GPR) profile across the beach ridges reveals the sedimentary structures and stratigraphic units. The beach ridges visible in the surface topography are a succession of stabilized foredunes that overlie progradational foreshore and upper shoreface sediments. The beach progrades show multiple truncation surfaces interpreted as storm events. The GPR profile shows that there are many more erosion surfaces in the subsurface than beach ridges on the surface. The width and dip of preserved beach progrades imaged by GPR shows that the shoreface has steepened from around 2·9° to around 7·5°. The changes in beach slope are attributed to increasing wave energy associated with beach progradation into deeper water as Guichen Bay was infilled. At the same time, the thickness of the preserved beach progrades increases slightly as the beach prograded into deeper water. Using the surface area of the ridge sets measured from the orthophotography, and the average thickness of upper shoreface, foreshore and coastal dune sands interpreted from the GPR profile, the volume of Holocene sediments within three of the six sets of beach-ridge accretion has been calculated. Combining optically stimulated luminescence (OSL) ages and volume calculations, rates of sediment accumulation for Ridge Sets 3, 4 and 5 have been estimated. Linear rates of beach-ridge progradation appear to decrease in the mid-Holocene. However, the rates of sediment accumulation calculated from beach volumes have remained remarkably consistent through the mid- to late Holocene. This suggests that sediment supply to the beach has been constant and that the decrease in the rate of progradation is due to increasing accommodation space as the beach progrades into deeper water. Changes in beach-ridge morphology and orientation reflect environmental factors such as changes in wave climate and wind regime. [ABSTRACT FROM AUTHOR]

1. The existence of perceived ecological impacts and development of adaptive management solutions to mitigate these problems are important issues in sustainable aquaculture. This paper examines the general impacts of two newly established trial longline installations on the infauna in Twofold Bay, a large, coastal embayment in south-east Australia. 2. We hypothesized that the physical presence of these longline installations and the biological activities of the mussels they supported would result in temporal changes in densities of infaunal taxa below installations differing from those at undisturbed control sites. We also predicted different patterns of variability in infauna between longline and control sites from before to after the longlines were stocked. These hypotheses were tested by using a beyond-BACI sampling design and asymmetrical analyses of variance to compare changes in densities of taxa at several different spatial scales below the proposed longline sites with those at two adjacent control sites, before and after the longlines were stocked. 3. After 18 months of longline operations, there was no evidence of any impact on total number of taxa, nor densities of individual taxa. Short-term temporal trends in densities in plots at control sites from April to May 2001 were often as different from each other as from those at the longline site. This indicates that densities of taxa at the farm site were within the range typically found at undisturbed sites, so there were no ecological impacts from the farm. 4. These results do not concur with previous studies on impact of mussel farming in semi-enclosed coastal waters. Differences in location, scale of production, duration of operation and assimilative capacity of the environment probably contributed to this discrepancy. The infauna in Twofold Bay either do not respond to this form of disturbance or have not yet been exposed to disturbance of a sufficient magnitude, or for a sufficient period of time, to elicit a detectable response. Better definition of the potential ecological impacts associated with aquaculture, plus their scale and magnitude in different environments is needed to design experiments and monitoring programmes to detect specific impacts. This activity can only be considered sustainable once we know that these impacts are localized, reversible and short-term. [ABSTRACT FROM AUTHOR]

Coastal evolution following the Holocene marine transgression in South Australia is examined under three contrasting coastal environments: the high-energy, microtidal southeast coast, and the Holocene barrier system of the Sir Richard and Younghusband peninsulas; the sandy deposits of the moderate-energy eastern Gulf St Vincent around the metropolitan Adelaide coastline; and the rapidly prograding sediments of the sheltered subtidal to supratidal gulf environments in the low-energy Upper Spencer Gulf. Although only the Upper Spencer Gulf case study provides detailed data on the Holocene sea level change, collectively, the three case studies illustrate differences in coastal evolution following the transgression, linked to factors such as regional variations in wave energy and wind regime, tidal range, and sediment availability. [ABSTRACT FROM AUTHOR]

Abstract: Large blooms of the marine cyanobacterium Lyngbya majuscula in Moreton Bay, Australia (27°05′S, 153°08′E) have been re-occurring for several years. A bloom was studied in Deception Bay (Northern Moreton Bay) in detail over the period January–March 2000. In situ data loggers and field sampling characterised various environmental parameters before and during the L. majuscula bloom. Various ecophysiological experiments were conducted on L. majuscula collected in the field and transported to the laboratory, including short-term (2h) 14C incorporation rates and long-term (7 days) pulse amplitude modulated (PAM) fluorometry assessments of photosynthetic capacity. The effects of L. majuscula on various seagrasses in the bloom region were also assessed with repeated biomass sampling. The bloom commenced in January 2000 following usual December rainfall events, water temperatures in excess of 24°C and high light conditions. This bloom expanded rapidly from 0 to a maximum extent of 8km2 over 55 days with an average biomass of 210gdw-1m-2 in late February, followed by a rapid decline in early April. Seagrass biomass, especially Syringodium isoetifolium, was found to decline in areas of dense L. majuscula accumulation. Dissolved and total nutrient concentrations did not differ significantly (P>0.05) preceding or during the bloom. However, water samples from creeks discharging into the study region indicated elevated concentrations of total iron (2.7–80.6μM) and dissolved organic carbon (2.5–24.7mgL-1), associated with low pH values (3.8–6.7). 14C incorporation rates by L. majuscula were significantly (P<0.05) elevated by additions of iron (5μM Fe), an organic chelator, ethylenediaminetetra-acetic acid (5μM EDTA) and phosphorus (5μM PO4-3). Photosynthetic capacity measured with PAM fluorometry was also stimulated by various nutrient additions, but not significantly (P>0.05). These results suggest that the L. majuscula bloom may have been stimulated by bioavailable iron, perhaps complexed by dissolved organic carbon. The rapid bloom expansion observed may then have been sustained by additional inputs of nutrients (N and P) and iron through sediment efflux, stimulated by redox changes due to decomposing L. majuscula mats. [Copyright &y& Elsevier]

We compare the biology of the tropical speciesSillago analisand the temperate speciesSillago schomburgkiiin Shark Bay, a large subtropical marine embayment on the west coast of Australia. This environment constitutes approximately the southernmost and northernmost limits of the distributions of these two species, respectively. The annuli visible in sectioned otoliths ofS. analisandS. schomburgkiiform annually. Their numbers were thus used to age the individuals of these two species, which are morphologically very similar and live in the same habitats. Although the growth rates ofS. analisandS. schomburgkiiare very similar until maturity is attained, they subsequently diverge, withS. schomburgkiiinvesting relatively more energy into somatic growth. The maximum total lengths and ages of both the females (320 mm, 6 years) and males (283 mm, 8 years) ofS. analiswere not as great as those of the females (383 mm, 9 years) and males (302 mm, 9 years) ofS. schomburgkii. In Shark Bay,S. schomburgkiispawns earlier and longer thanS. analis, i.e. August-December vs. January-March, which would result in the juveniles of these two species recruiting into nursery areas at different times. In addition,S. schomburgkiispawns earlier and for longer in Shark Bay than in temperate marine waters 800 km further south, presumably reflecting the fact that, in that subtropical embayment, water temperatures over which this species typically spawns are attained earlier and last for longer. However, although environmental conditions in Shark Bay and those temperate marine waters differ markedly, the growth of the corresponding sexes ofS. schomburgkiiin these two water bodies is similar. [ABSTRACT FROM AUTHOR]

Remote videography was used to investigate relationships between biological similarity and distance in Moreton Bay, Australia at site (1 km) and local (10 km) scales, and for separate biotic groups. Numerical analysis using Mantel’s tests to compare distance and similarity matrices showed that at both scales there was a negative correlation between similarity and distance, in that sites further apart were less similar than sites close together. The relationship, although significant (p<0.001), was quite weak (R2=5%) at the site-scale, with no significant (ANOVA with Tukey’s pairwise comparisons,p>0.05) decline in similarity up to distances of 2.1-2.6 km. At the local-scale, between-site similarity was high (mean Bray-Curtis similarity>30% for 4th root transformed data) at scales of 10 km or less, and declined markedly with increasing distance. Scales of similarity for different broad taxonomic and functional groups within Moreton Bay were broadly consistent between groups and with the complete dataset. There was evidence of patchiness in the distributions of seagrass and anthozoans at scales less than 16 km. In other biotic groups there was an essentially monotonic decline in similarity with distance. The study showed that the spatial classification approach to habitat mapping is valid in this case, and that site spacing of less than 10 km is necessary to capture important components of biological similarity. Site spacing of less than 2.5 km does not appear to be warranted to capture additional components of biological similarity at the scales studied. [ABSTRACT FROM AUTHOR]

The article presents a study that examines the influence of hydrogen-ion concentration (pH) and salinity on copper, lead and zinc sorption rates by two sediments from Moreton Bay, Australia, with contrasting physical and chemical properties. The rate and magnitude of metal sorption was negatively affected by salinity due to (1) increased competition for the limited number of sorption sites, (2) reduced activity of aqueous trace metal species, and (3) ion-pair formation with artificial seawater anions. The findings from this study indicate that at the pH of the estuarine environment of Moreton Bay, a high proportion of metals added in urban runoff are likely to be sorbed very quickly by the sediments at their point of entry.

The habitat of a population of coastal goannas (Varanus panoptes) was assessed at Fog Bay, Australia, by a combination of scat analysis, radio tracking, burrow counts, and sightings. Tracks were followed to assess spatial and temporal beach use. Scat analyses showed that goannas ate a variety of prey from the beach and dunes. Sea turtle eggs were the dominant prey found in scats during the dry season. All four census methods showed that goannas selected the beach habitat and dunes, although habitat selection indices were highest for the beach. Goannas used the beach throughout the year with peak beach activity occurring in May and November. There was no indication that sea turtle nesting influenced the timing of beach activities or how long goannas spent on the beach. The seasonal activity patterns of V. panoptes at Fog Bay is unlike V. panoptes in other areas and appears to be related to food availability. Although goannas prey on a large portion of sea turtle nests on the Fog Bay mainland, more research is required on the demography of the sea turtles to assess whether this has impacts on the size of the sea turtle populations. [ABSTRACT FROM AUTHOR]

A high-resolution numerical model is used to study the mean wintertime shelf-slope circulation between the Gulfs of South Australia and the west coast of Tasmania. The mean downwelling-favorable winds for the region result in a continuous eastward coastal current (CC) extending from Cape Leeuwin to the eastern coast of Tasmania. The magnitude of the CC is generally largest over the shelf break, has speeds of more than 40 cm s[sup -1] [transport 2.4 Sv (Sv ≡ 10[sup 6] m[sup 3] s[sup -1] )], and is generally in good agreement with observations. The relative importance of the Leeuwin Current, zonal winds, and density gradients to the shelf circulation is established. Within Bass Strait, the eastward circulation is in good agreement with observations and simple models show that about 30% of the transport arises from local winds and the remainder from the CC. The total transport through the strait (0.95 Sv) is shown to be controlled by sea level on the east coast of Tasmania. A current of up to 10 cm s[sup -1] is also found to flow from Tasmania to Esperance in the far west (transport 6.8 Sv) and to be centered within the permanent thermocline (depth 600 m) and near the shelf slope. This Flinders Current arises from the equatorward Sverdrup transport but is also fed by the “Tasman outflow” that enters the region off of the southern tip of Tasmania. A sensitivity study shows that dense water formation occurs off of Spencer Gulf and the cascade to depths of 250 m is in qualitative agreement with observations. Dense water formed near the coast can enhance the CC by up to 5 cm s[sup -1] . Suggestions for future modeling and observational studies are made. [ABSTRACT FROM AUTHOR]