ORCID Profile
0000-0001-9459-111X
Current Organisations
University of Newcastle - Central Coast Campus
,
Deakin University
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Publisher: MDPI AG
Date: 02-02-2021
Abstract: The way an animal behaves in its habitat provides insight into its ecological role. As such, collecting robust, accurate datasets in a time-efficient manner is an ever-present pressure for the field of behavioural ecology. Faced with the shortcomings and physical limitations of traditional ground-based data collection techniques, particularly in marine studies, drones offer a low-cost and efficient approach for collecting data in a range of coastal environments. Despite drones being widely used to monitor a range of marine animals, they currently remain underutilised in ray research. The innovative application of drones in environmental and ecological studies has presented novel opportunities in animal observation and habitat assessment, although this emerging field faces substantial challenges. As we consider the possibility to monitor rays using drones, we face challenges related to local aviation regulations, the weather and environment, as well as sensor and platform limitations. Promising solutions continue to be developed, however, growing the potential for drone-based monitoring of behaviour and habitat use of rays. While the barriers to enter this field may appear daunting for researchers with little experience with drones, the technology is becoming increasingly accessible, helping ray researchers obtain a wide range of highly useful data.
Publisher: Wiley
Date: 05-06-2019
DOI: 10.1111/FME.12351
Publisher: European Respiratory Society (ERS)
Date: 17-12-2020
DOI: 10.1183/13993003.03317-2020
Abstract: Current incidence and outcome of patients with acute hypoxaemic respiratory failure requiring mechanical ventilation in the intensive care unit (ICU) are unknown, especially for patients not meeting criteria for acute respiratory distress syndrome (ARDS). An international, multicentre, prospective cohort study of patients presenting with hypoxaemia early in the course of mechanical ventilation, conducted during four consecutive weeks in the winter of 2014 in 459 ICUs from 50 countries (LUNG SAFE). Patients were enrolled with arterial oxygen tension/inspiratory oxygen fraction ratio ≤300 mmHg, new pulmonary infiltrates and need for mechanical ventilation with a positive end-expiratory pressure of ≥5 cmH 2 O. ICU prevalence, causes of hypoxaemia, hospital survival and factors associated with hospital mortality were measured. Patients with unilateral versus bilateral opacities were compared. 12 906 critically ill patients received mechanical ventilation and 34.9% with hypoxaemia and new infiltrates were enrolled, separated into ARDS (69.0%), unilateral infiltrate (22.7%) and congestive heart failure (CHF 8.2%). The global hospital mortality was 38.6%. CHF patients had a mortality comparable to ARDS (44.1% versus 40.4%). Patients with unilateral-infiltrate had lower unadjusted mortality, but similar adjusted mortality compared to those with ARDS. The number of quadrants on chest imaging was associated with an increased risk of death. There was no difference in mortality comparing patients with unilateral-infiltrate and ARDS with only two quadrants involved. More than one-third of patients receiving mechanical ventilation have hypoxaemia and new infiltrates with a hospital mortality of 38.6%. Survival is dependent on the degree of pulmonary involvement whether or not ARDS criteria are reached.
Publisher: CSIRO Publishing
Date: 2017
DOI: 10.1071/MF15369
Abstract: Two species of angel shark (Squatina australis, S. albipunctata) and two species of sawshark (Pristiophorus nudipinnis, P. cirratus) are frequently caught in south-eastern Australia. Little is known of the biology of these elasmobranchs, despite being caught as secondary target species in large numbers. The present study collected morphometric and reproductive data from sharks caught in shark-control nets, commercial fishing trawlers and research trawlers in south-eastern Australia. All four species had female-biased sexual size dimorphism, but growth curves between sexes did not differ. Male S. australis in iduals were fully mature at ~800-mm total length, male P. nudipinnis at ~900mm, and male P. cirratus at ~800mm. Anterior pectoral margins could be used to determine total length in all species. No morphometric measurement could reliably separate Squatina spp. or Pristiophorus spp., although S. albipunctata over 1000-mm total length had larger eyes than did S. australis.
Publisher: MDPI AG
Date: 27-02-2023
Abstract: The use of drones to study the behaviours of marine animals is increasing, yet the potential effects of drones on natural behaviours are poorly understood. Here, we assessed if a small consumer drone produced behavioural changes in a ray common to New South Wales, Australia, the estuary stingray (Dasyatis fluviorum). A drone was flown directly above a total of 50 in idual stingrays, the altitude above that ray was progressively reduced, and any behavioural changes were recorded. While stingrays demonstrated a range of behaviours, these behaviours rarely changed during drone observations (n = 6 or 12% of flights), and no change in the type of behaviour or number of behavioural changes was observed as the altitude decreased. These results suggest that consumer drones have little visible impact on stingray behaviour but do not exclude potential physiological responses. As a result, we recommend that when conducting drone-based stingray research, operators fly at the highest altitude possible that allows monitoring of features of interest, and we conclude that drones are effective tools for assessing natural stingray behaviours.
Publisher: Wiley
Date: 13-06-2019
DOI: 10.1111/JFB.14010
Abstract: We determined stable-isotope ratios for replicate muscle tissues in 13 gravid Mobula kuhlii cf. eregoodootenkee (110.4-120.4 cm disc width W
Publisher: CSIRO Publishing
Date: 03-05-2023
DOI: 10.1071/MF22103
Abstract: Context Primary production on coral reefs varies under changing conditions such as light and nutrient availability. This variation causes changes in basal stable isotopes as photosynthetic and nutrient pathways change. Aims This study provides a preliminary baseline of nitrogen (δ15N) and carbon (δ13C) stable isotope profiles in Symbiodinium and macroalgae at a spatial scale and along a depth gradient around an island. Methods Coral fragments and macroalgae were collected at depths from the surface to 26 m. δ15N and δ13C stable isotope values were assessed for Symbiodinium relative to cell density per surface area. Key results δ15N values showed a uniform nutrient profile across primary producers. However, chlorophyll-a and Symbiodinium density from Montipora stellata had higher concentrations on the southern side of the island. δ15N values of Symbiodinium from Stylophora pistillata and macroalgae did not change with depth. Depth was associated with a significant decrease in Symbiodinium density, and δ13C values in macroalgae. Conclusions We attribute these findings to Symbiodinium from S. pistillata as depth increases, decreasing cell density but maintaining chlorophyll-a concentration to satisfy the coral-host nutrient requirements. Implications This study sets the scene for future, more comprehensive research on detecting carbon and nitrogen stable isotope values on primary producers in coral reefs.
Publisher: MDPI AG
Date: 24-12-2020
DOI: 10.3390/RS13010040
Abstract: Coastal ecosystems are under threat from a range of anthropogenic impacts that disrupt habitat connectivity and the ability for animals to move within them. Understanding fine-scale animal movement provides insight into how animals are responding to these pressures, and underpins effective ecological management and conservation strategies. This study used drones to investigate the drivers of the fine-scale movement of rays in coastal estuaries using the short-tail stingray (Bathytoshia brevicaudata) as a model species. Smaller rays swam with more regular bursts of speed and greater sinuosity than larger in iduals, indicating that rays of different sizes alter their fine-scale movement behavior to maintain energetic efficiency. Rays were less likely to spend time resting and swam faster on the high tide compared to the outgoing tide. They were also more likely to exhibit bursts of speed at noon (11 am to 1 pm) than at other times of day. Body size, tide and time of day all influenced ray movement. Understanding the ecological variables that influence the fine-scale movement of rays and the potential for human activities to alter natural behaviors is integral to the implementation of effective management strategies for this group of animals and their ecosystems.
Publisher: Elsevier BV
Date: 2018
Publisher: Elsevier BV
Date: 2017
DOI: 10.1016/J.MARPOLBUL.2016.10.069
Abstract: Continued growth of tourism has led to concerns about direct and indirect impacts on the ecology of coral reefs and ultimate sustainability of these environments under such pressure. This research assessed impacts of reef walking by tourists on a relatively pristine reef flat community associated with an 'ecoresort' on the Great Barrier Reef, Australia. Heavily walked areas had lower abundances of live hard coral but greater amounts of dead coral and sediment. Abundances of macroalgae were not affected between sites. Coral-associated butterflyfish were less abundant and less erse in more tr led sites. A manipulative experiment showed handling holothurians on reef walks had lasting negative impacts. This is the first study to show potential impacts of such handling on holothurians. Ecological impacts of reef walking are weighed against sociocultural benefits of a first hand experience in nature.
Publisher: Springer Science and Business Media LLC
Date: 26-06-2021
Publisher: Springer Science and Business Media LLC
Date: 08-07-2021
DOI: 10.1038/S41586-021-03767-X
Abstract: The genetic make-up of an in idual contributes to the susceptibility and response to viral infection. Although environmental, clinical and social factors have a role in the chance of exposure to SARS-CoV-2 and the severity of COVID-19 1,2 , host genetics may also be important. Identifying host-specific genetic factors may reveal biological mechanisms of therapeutic relevance and clarify causal relationships of modifiable environmental risk factors for SARS-CoV-2 infection and outcomes. We formed a global network of researchers to investigate the role of human genetics in SARS-CoV-2 infection and COVID-19 severity. Here we describe the results of three genome-wide association meta-analyses that consist of up to 49,562 patients with COVID-19 from 46 studies across 19 countries. We report 13 genome-wide significant loci that are associated with SARS-CoV-2 infection or severe manifestations of COVID-19. Several of these loci correspond to previously documented associations to lung or autoimmune and inflammatory diseases 3–7 . They also represent potentially actionable mechanisms in response to infection. Mendelian randomization analyses support a causal role for smoking and body-mass index for severe COVID-19 although not for type II diabetes. The identification of novel host genetic factors associated with COVID-19 was made possible by the community of human genetics researchers coming together to prioritize the sharing of data, results, resources and analytical frameworks. This working model of international collaboration underscores what is possible for future genetic discoveries in emerging pandemics, or indeed for any complex human disease.
Publisher: Wiley
Date: 15-03-2022
DOI: 10.1111/JFB.15028
Abstract: Australian cownose rays ( Rhinoptera neglecta ) and whitespotted eagle rays ( Aetobatus ocellatus ) are large myliobatiform rays that co‐occur off temperate eastern Australia. Here, we performed stable‐isotope analyses (δ 13 C, δ 15 N and δ 34 S) on fin clips of both species to gain insights into their trophic interactions and isotopic niches, and assess the effect of preservation (ethanol‐stored versus frozen) on isotopic values of fin‐clip tissue of R. neglecta . Linear mixed models identified species as the main factor contributing to variation among δ 15 N and δ 34 S values, and disc width for δ 13 C. Bayesian ecological niche modelling indicated a 57.4% to 74.5% overlap of trophic niches, with the niche of R. neglecta being smaller and more constrained. Because values of δ 13 C were similar between species, variation in isotopic niches were due to differences in δ 15 N and δ 34 S values. Linear mixed models failed to detect differences in isotopic values of ethanol‐stored and frozen fin tissue of R. neglecta . This study provides the first examination of the trophic ecology of R. neglecta and the comparison of isotopic niche with A. ocellatus , which will facilitate future research into the trophic interactions of these species and aid better resource management.
Publisher: Springer Science and Business Media LLC
Date: 10-12-2021
DOI: 10.1007/S00439-021-02397-7
Abstract: The combined impact of common and rare exonic variants in COVID-19 host genetics is currently insufficiently understood. Here, common and rare variants from whole-exome sequencing data of about 4000 SARS-CoV-2-positive in iduals were used to define an interpretable machine-learning model for predicting COVID-19 severity. First, variants were converted into separate sets of Boolean features, depending on the absence or the presence of variants in each gene. An ensemble of LASSO logistic regression models was used to identify the most informative Boolean features with respect to the genetic bases of severity. The Boolean features selected by these logistic models were combined into an Integrated PolyGenic Score that offers a synthetic and interpretable index for describing the contribution of host genetics in COVID-19 severity, as demonstrated through testing in several independent cohorts. Selected features belong to ultra-rare, rare, low-frequency, and common variants, including those in linkage disequilibrium with known GWAS loci. Noteworthily, around one quarter of the selected genes are sex-specific. Pathway analysis of the selected genes associated with COVID-19 severity reflected the multi-organ nature of the disease. The proposed model might provide useful information for developing diagnostics and therapeutics, while also being able to guide bedside disease management.
Publisher: MDPI AG
Date: 08-11-2018
Abstract: Determining the small-scale movement patterns of marine vertebrates usually requires invasive active acoustic tagging or in-water monitoring, with the inherent behavioural impacts of those techniques. In addition, these techniques rarely allow direct continuous behavioural assessments or the recording of environmental interactions, especially for highly mobile species. Here, we trial a novel method of assessing small-scale movement patterns of marine vertebrates using an unmanned aerial vehicle that could complement longer-term tracking approaches. This approach is unlikely to have behavioural impacts and provides high accuracy and high frequency location data (10 Hz), while subsequently allowing quantitative trajectory analysis. Unmanned aerial vehicle tracking is also relatively low cost compared to single-use acoustic and GPS tags. We tracked 14 sharks for up to 10 min in a shallow lagoon of Heron Island, Australia. Trajectory analysis revealed that Epaulette sharks (Hemiscyllium ocellatum) displayed sinusoidal movement patterns, while Blacktip Reef Sharks (Carcharhinus melanopterus) had more linear trajectories that were similar to those of a Lemon shark (Negaprion acutidens). In idual shark trajectory patterns and movement speeds were highly variable. Results indicate that Epaulette sharks may be more mobile during diurnal low tides than previously thought. The approach presented here allows the movements and behaviours of marine vertebrates to be analysed at resolutions not previously possible without complex and expensive acoustic arrays. This method would be useful to assess the habitat use and behaviours of sharks and rays in shallow water environments, where they are most likely to interact with humans.
Publisher: Elsevier BV
Date: 2020
Publisher: Elsevier BV
Date: 05-2022
Publisher: Springer Science and Business Media LLC
Date: 12-07-2021
Publisher: MDPI AG
Date: 21-01-2021
Abstract: Over the past decade, drones have become a popular tool for wildlife management and research. Drones have shown significant value for animals that were often difficult or dangerous to study using traditional survey methods. In the past five years drone technology has become commonplace for shark research with their use above, and more recently, below the water helping to minimise knowledge gaps about these cryptic species. Drones have enhanced our understanding of shark behaviour and are critically important tools, not only due to the importance and conservation of the animals in the ecosystem, but to also help minimise dangerous encounters with humans. To provide some guidance for their future use in relation to sharks, this review provides an overview of how drones are currently used with critical context for shark monitoring. We show how drones have been used to fill knowledge gaps around fundamental shark behaviours or movements, social interactions, and predation across multiple species and scenarios. We further detail the advancement in technology across sensors, automation, and artificial intelligence that are improving our abilities in data collection and analysis and opening opportunities for shark-related beach safety. An investigation of the shark-based research potential for underwater drones (ROV/AUV) is also provided. Finally, this review provides baseline observations that have been pioneered for shark research and recommendations for how drones might be used to enhance our knowledge in the future.
Publisher: Springer Science and Business Media LLC
Date: 11-12-2021
DOI: 10.1038/S41586-020-03065-Y
Abstract: Host-mediated lung inflammation is present
Publisher: Wiley
Date: 19-08-2021
DOI: 10.1002/RCM.9167
Abstract: Stable isotopes are used to study trophic and movement ecology in aquatic systems, as they provide spatially distinct, time‐integrated signatures of diet. Stable isotope ecology has been used to quantify species‐habitat relationships in many important fisheries species (e.g., penaeid prawns), with approaches that typically assume constant values for diet‐tissue discrimination and diet‐tissue steady state, but these can be highly variable. Here we provide the first report of these processes in Metapenaeus macleayi (eastern school prawn). Here we explicitly measure and model carbon (δ 13 C) and nitrogen (δ 15 N) diet‐tissue discrimination and turnover in eastern school prawn muscle tissue as a function of experimental time following a change in diet to an isotopically distinct food source. Diet‐tissue discrimination factors were 5 and 0.6‰ for δ 13 C and δ 15 N, respectively. Prawn muscle tissue reached an approximate steady state after approximately 50 and 30 days for δ 13 C and δ 15 N. Half‐lives indicated faster turnover of δ 15 N (~8 days) than δ 13 C (~14 days). Our diet‐tissue discrimination factors deviate from ‘typical’ values with larger values for carbon than nitrogen isotopes, but are generally similar to those measured in other crustaceans. Similarly, our estimates of isotopic turnover align with those in other penaeid species. These findings confirm muscle tissue as a reliable indicator of long‐term diet and movement patterns in eastern school prawn.
Publisher: Ubiquity Press, Ltd.
Date: 2021
DOI: 10.5334/IJIC.5679
Publisher: CSIRO Publishing
Date: 2020
DOI: 10.1071/MF19277
Abstract: Sawsharks are one of the least well-known groups of sharks globally, yet they are caught in large numbers in south-eastern Australia. In this study we assessed spatiotemporal patterns of distribution of two co-occurring species of sawsharks, namely the common sawshark (Pristiophorus cirratus) and the southern sawshark (Pristiophorus nudipinnis), to guide future research in this area. To identify where the animals may occur in greater numbers, this study used the major commercial fishery datasets in the region, containing nearly 180000 catch records from 1990 to 2017. Several general patterns were evident. Sawsharks occurred at shallower and deeper depths than previously thought, and their geographical range was larger than documented in previous studies. Depth distributions of both species overlapped, but P. cirratus appeared more common in deeper water (at depths up to 500m), with peak common sawshark catch rates at ~400m. Seasonal standardised catch patterns across fishing methods suggested that migrations from deeper to shallower waters may occur in the Australasian autumn and winter. The greatest concentration of sawsharks, inferred by standardised catch rates, occurred to the east and west of Bass Strait between Tasmania and mainland Australia. Although standardised catch rates of sawsharks declined in gill-net fisheries by ~30%, primarily in the Bass Strait and Tasmania, sawsharks appear to be caught at consistent rates since the 1990s, inferring a possible resilience of these sharks to current levels of fishing pressure.
Publisher: Elsevier BV
Date: 02-2021
Publisher: Wiley
Date: 29-03-2022
DOI: 10.1111/JFB.15034
Abstract: Patterns of mother–embryo fractionation of 13 C and 15 N were assessed for their predictability across three species of batoids caught as by‐catch in south‐eastern Australia. Stable isotope analysis of 24 mothers and their litters revealed that isotope ratios of embryos were significantly different from their corresponding mothers and that the scale and direction of the difference varied within and across species. The range of variation across species was 3.5‰ for δ 13 C and 4‰ for δ 15 N, equivalent to a difference in trophic level. In one species ( Urolophus paucimaculatus ) litters could be significantly enriched or depleted in 13 C and 15 N relative to their mothers' isotope signatures. These results suggest that patterns of mother–embryo isotope fractionation vary within and between species and that these patterns may not be explained only by developmental mode. Contrasting patterns of fractionation between and within species make it difficult to adjust mother–embryo fractionation with broad‐scale correction factors.
Publisher: Wiley
Date: 27-08-2020
DOI: 10.1111/JFB.14463
Publisher: Springer Science and Business Media LLC
Date: 20-11-2011
Publisher: Wiley
Date: 16-06-2020
DOI: 10.1111/JFB.14381
Publisher: Elsevier BV
Date: 03-2019
Publisher: Springer Science and Business Media LLC
Date: 18-01-2018
DOI: 10.1038/S41559-017-0432-Z
Abstract: Sharks are a erse group of mobile predators that forage across varied spatial scales and have the potential to influence food web dynamics. The ecological consequences of recent declines in shark biomass may extend across broader geographic ranges if shark taxa display common behavioural traits. By tracking the original site of photosynthetic fixation of carbon atoms that were ultimately assimilated into muscle tissues of 5,394 sharks from 114 species, we identify globally consistent biogeographic traits in trophic interactions between sharks found in different habitats. We show that populations of shelf-dwelling sharks derive a substantial proportion of their carbon from regional pelagic sources, but contain in iduals that forage within additional isotopically erse local food webs, such as those supported by terrestrial plant sources, benthic production and macrophytes. In contrast, oceanic sharks seem to use carbon derived from between 30° and 50° of latitude. Global-scale compilations of stable isotope data combined with biogeochemical modelling generate hypotheses regarding animal behaviours that can be tested with other methodological approaches.
Publisher: Massachusetts Medical Society
Date: 26-08-2021
Publisher: Elsevier BV
Date: 11-2018
Publisher: Elsevier BV
Date: 2022
Publisher: Springer Science and Business Media LLC
Date: 18-07-2016
DOI: 10.1038/SREP29698
Abstract: Determining the age of sharks using vertebral banding is a vital component of management, but the causes of banding are not fully understood. Traditional shark ageing is based on fish otolith ageing methods where growth bands are assumed to result from varied seasonal calcification rates. Here we investigate these assumptions by mapping elemental distribution within the growth bands of vertebrae from six species of sharks representing four different taxonomic orders using scanning x-ray fluorescence microscopy. Traditional visual growth bands, determined with light microscopy, were more closely correlated to strontium than calcium in all species tested. Elemental distributions suggest that vertebral strontium bands may be related to environmental variations in salinity. These results highlight the requirement for a better understanding of shark movements, and their influence on vertebral development, if confidence in age estimates is to be improved. Analysis of shark vertebrae using similar strontium-focused elemental techniques, once validated for a given species, may allow more successful estimations of age on in iduals with few or no visible vertebral bands.
Publisher: Elsevier BV
Date: 11-2020
Publisher: Elsevier BV
Date: 11-2021
Publisher: Massachusetts Medical Society
Date: 26-08-2021
Publisher: PeerJ
Date: 08-06-2017
DOI: 10.7717/PEERJ.3445
Abstract: The spatial learning skills of high and low stress juvenile mulloway ( Argyrosomus japonicus ) were tested in a dichotomous choice apparatus. Groups of fish were formed based on background blood cortisol levels and required to learn the location of a food reward hidden in one of two compartments. Low stress fish characterised by low background levels of the stress hormone cortisol had higher activity levels and entered both rewarded and unrewarded rooms frequently. Within the first week of exposure, however, their preference for the rewarded room increased, indicative of learning. Fish that had high background levels of cortisol, in contrast, showed low levels of activity but when they chose between the two rooms they chose the rewarded room most often but showed less improvement over time. After 12 days in the apparatus, both low and high stress fish had similar ratios of rewarded vs unrewarded room entrances. Our results suggest that proactive coping styles may increase exposure to novel contexts and thus favour faster learning but at the cost of reduced initial accuracy.
Publisher: Public Library of Science (PLoS)
Date: 11-01-2018
Publisher: Springer Science and Business Media LLC
Date: 08-03-2021
Publisher: Springer Science and Business Media LLC
Date: 08-06-2021
Publisher: CSIRO
Date: 2020
DOI: 10.25919/Y5DA-0919
Publisher: Elsevier BV
Date: 12-2018
Publisher: MDPI AG
Date: 18-07-2017
DOI: 10.3390/RS9070740
Publisher: Elsevier BV
Date: 05-2021
Publisher: Springer Science and Business Media LLC
Date: 02-02-2021
Publisher: Wiley
Date: 02-2012
Publisher: Wiley
Date: 23-12-2022
Abstract: Dietary specialisations are important determinants of ecological structure, particularly in species with high per‐capita trophic influence like marine apex predators. These species are, however, among the most challenging in which to establish spatiotemporally integrated diets. We introduce a novel integration of stable isotopes with a multidimensional nutritional niche framework that addresses the challenges of establishing spatiotemporally integrated nutritional niches in wild populations, and apply the framework to explore in idual diet specialisation in a marine apex predator, the white shark Carcharodon carcharias . Sequential tooth files were s led from juvenile white sharks to establish in idual isotopic (δ‐space δ 13 C, δ 15 N, δ 34 S) niche specialisation. Bayesian mixing models were then used to reveal in idual‐level prey (p‐space) specialisation, and further combined with nutritional geometry models to quantify the nutritional (N‐space) dimensions of in idual specialisation, and their relationships to prey use. Isotopic and mixing model analyses indicated juvenile white sharks as in idual specialists within a broader, generalist, population niche. In idual sharks differed in their consumption of several important mesopredator species, which suggested among‐in idual variance in trophic roles in either pelagic or benthic food webs. However, variation in nutrient intakes was small and not consistently correlated with differences in prey use, suggesting white sharks as nutritional specialists and that in iduals could use functionally and nutritionally different prey as complementary means to achieve a common nutritional goal. We identify how degrees of in idual specialisation can differ between niche spaces (δ‐, p‐ or N‐space), the physiological and ecological implications of this, and argue that integrating nutrition can provide stronger, mechanistic links between diet specialisation and its intrinsic (fitness erformance) and extrinsic (ecological) outcomes. Our time‐integrated framework is adaptable for examining the nutritional consequences and drivers of food use variation at the in idual, population or species level.
Publisher: Elsevier BV
Date: 05-2021
Publisher: Frontiers Media SA
Date: 03-12-2020
DOI: 10.3389/FMARS.2020.594636
Abstract: Determining the geographic range of widely dispersed or migratory marine organisms is notoriously difficult, often requiring considerable costs and typically extensive tagging or exploration programs. While these approaches are accurate and can reveal important information on the species, they are usually conducted on only a small number of in iduals and can take years to produce relevant results, so alternative approaches may be preferable. The presence of latitudinal gradients in stable carbon isotope compositions of marine phytoplankton offers a means to quickly determine likely geographic population ranges of species that rely on productivity from these resources. Across sufficiently large spatial and temporal scales, the stable carbon isotopes of large coastal or pelagic marine species should reflect broad geographic patterns of resource use, and could be used to infer geographic ranges of marine populations. Using two methods, one based on a global mechanistic model and the other on targeted low-cost latitudinal s ling of fishes, we demonstrate and compare these stable isotope approaches to determine the core population geography of an apex predator, the great hammerhead ( Sphyrna mokarran ). Both methods indicated similar geographic ranges and suggested that S. mokarran recorded in south-eastern Australia are likely to be from more northern Australian waters. These approaches could be replicated in other areas where coastlines span predictable geographic gradients in isotope values and be used to determine the core population geography of highly mobile species to inform management decisions.
Publisher: The Royal Society
Date: 07-2021
Publisher: CSIRO Publishing
Date: 16-11-2021
DOI: 10.1071/MF21155
Abstract: Temperate soft corals are found in many estuaries around the world and often form large habitats in these environments, yet the functional ecology of soft corals is poorly understood. To understand the functional role of a soft coral in temperate ecosystems, we examined the role of the endangered Dendronepthya australis cauliflower coral as habitat for fishes and invertebrates, and whether associated species used the soft coral as a food source. Using Bayesian stable isotope mixing models of δ13C and δ15N values of soft corals and a suite of potential invertebrate consumers, we found that five of eight soft-coral-associated invertebrates were all likely to be feeding almost exclusively on the soft corals. In situ feeding experiments conducted using baited remote underwater video systems (BRUVS) with soft coral cuttings as ‘bait’ did not identify any larger species as consumers. Fish assemblages studied using remote underwater video systems (RUVS) were erse in the soft coral habitat and overlapped with assemblages of both sediment and seagrass environments. These results highlighted that these soft corals have a valuable trophic role in estuarine food webs through trophic transfer of nutrients via invertebrate consumers, and that soft coral habitats are used by commercially and recreationally important fishes.
Publisher: American Medical Association (AMA)
Date: 02-11-2021
Publisher: Canadian Science Publishing
Date: 11-2015
Abstract: Despite the global distribution of sawsharks, little is known about their diets or their role in the marine biosphere. As species in higher trophic positions are generally considered to be more at risk to perturbations such as fishing, understanding their role in the food chain will enable better conservation and management strategies for these species. Two sawshark species (Pristiophorus cirratus, Pristiophorus nudipinnis) co-occur in waters off east Tasmania, Australia. This study determined the trophic positions of these sawsharks and whether they avoided competing with each other through resource partitioning. Isotopic analysis of muscle tissue revealed that P. cirratus and P. nudipinnis had significantly different trophic levels, with P. cirratus likely to have a diet of primary consumers and P. nudipinnis likely to have a piscivorous diet. Owing to their different isotopic signatures, it is also likely that the sawshark rostrum has multiple functions. Both species shifted to higher trophic levels during ontogeny. Maternal isotopic signatures were detectable in P. cirratus juveniles.
Publisher: MDPI AG
Date: 20-01-2020
DOI: 10.3390/PUBLICATIONS8010004
Abstract: The current peer review system is under stress from ever increasing numbers of publications, the proliferation of open-access journals and an apparent difficulty in obtaining high-quality reviews in due time. At its core, this issue may be caused by scientists insufficiently prioritising reviewing. Perhaps this low prioritisation is due to a lack of understanding on how many reviews need to be conducted by researchers to balance the peer review process. I obtained verified peer review data from 142 journals across 12 research fields, for a total of over 300,000 reviews and over 100,000 publications, to determine an estimate of the numbers of reviews required per publication per field. I then used this value in relation to the mean numbers of authors per publication per field to highlight a ‘review ratio’: the expected minimum number of publications an author in their field should review to balance their input (publications) into the peer review process. On average, 3.49 ± 1.45 (SD) reviews were required for each scientific publication, and the estimated review ratio across all fields was 0.74 ± 0.46 (SD) reviews per paper published per author. Since these are conservative estimates, I recommend scientists aim to conduct at least one review per publication they produce. This should ensure that the peer review system continues to function as intended.
Publisher: MDPI AG
Date: 25-09-2020
Abstract: The use of drones to study marine animals shows promise for the examination of numerous aspects of their ecology, behaviour, health and movement patterns. However, the responses of some marine phyla to the presence of drones varies broadly, as do the general operational protocols used to study them. Inconsistent methodological approaches could lead to difficulties comparing studies and can call into question the repeatability of research. This review draws on current literature and researchers with a wealth of practical experience to outline the idiosyncrasies of studying various marine taxa with drones. We also outline current best practice for drone operation in marine environments based on the literature and our practical experience in the field. The protocols outlined herein will be of use to researchers interested in incorporating drones as a tool into their research on marine animals and will help form consistent approaches for drone-based studies in the future.
Publisher: Springer Science and Business Media LLC
Date: 09-10-2020
Publisher: Elsevier BV
Date: 11-2020
Publisher: CSIRO
Date: 2020
DOI: 10.25919/R9WG-1V84
Publisher: Wiley
Date: 27-07-2022
DOI: 10.1002/RCM.9346
Abstract: The use of sulfur isotopes to study trophic ecology in marine ecosystems has increased in the past decade. Unlike other commonly used isotopes (e.g., carbon), sulfur can better discriminate benthic and pelagic productivity. However, how lipid extraction affects sulfur isotopic values has not been assessed, despite its frequent use to remove lipid effects on δ We used white muscle and liver s les from two species of sharks and skin s les from two species of pinnipeds (sea lion and fur seal) to assess the effects of lipid extraction on stable isotope values for δ Lipid extraction significantly decreased δ Lipid extraction did not have a strong impact on δ
Publisher: Elsevier BV
Date: 02-2019
Publisher: CSIRO Publishing
Date: 28-11-2022
DOI: 10.1071/MF22050
Abstract: Context Shipping impacts are a major environmental concern that can affect the behaviour and health of marine mammals and fishes. The potential impacts of shipping within marine parks is rarely considered during the planning process. Aims We assessed the areal disturbance footprint of shipping around Australia, its overlap with marine parks, and known locations of megafauna, so as to identify areas of concern that warrant further investigation. Methods Automatic Identification System (AIS) shipping data from 2018 to 2021 were interpreted through a kernel-density distribution and compared with satellite data from ∼200 in iduals of megafauna amalgamated from 2003 to 2018, and the locations of marine parks. Key results Over 18% of marine parks had shipping exposure in excess of 365 vessels per year. Around all of Australia, 39% of satellite-tag reports from whale shark and 36.7% of pygmy blue and humpback whale satellite-tag reports were in moderate shipping-exposure areas ( ships per year). Shipping exposure significantly increased from 2018 despite the pandemic, including within marine parks. Conclusions These results highlight the wide-scale footprint of commercial shipping on marine ecosystems that may be increasing in intensity over time. Implications Consideration should be made for assessing and potentially limiting shipping impacts along migration routes and within marine parks.
Publisher: Wiley
Date: 23-10-2019
DOI: 10.1111/JFB.14160
Abstract: Great hammerhead sharks Sphyrna mokarran are the largest member of Sphyrnidae, yet the roles of these large sharks in the food webs of coastal ecosystems are still poorly understood. Here we obtained s les of muscle, liver and vertebrae from large S. mokarran (234-383 cm total length L
Publisher: Wiley
Date: 22-03-2023
DOI: 10.1111/JFB.15370
Abstract: Recreational fishing waste, produced from processing catches at shore‐based fish cleaning facilities and discarded into adjacent waters, is foraged by various aquatic species. However, the potential alterations to the diet of consumers of these resources are poorly studied. Smooth stingrays ( Bathytoshia brevicaudata ) are a large demersal mesopredatory ray species and common scavenger of recreational fishing discards around southern Australia. Due to their attraction to fish cleaning sites, they are also common targets of unregulated ‘stingray feeding’ tourism where they are fed commercially produced baits ( e.g. , pilchards). This study provides a preliminary assessment of the diet of smooth stingrays provisioned recreational fishing discards and baits at two sites in southern New South Wales, Australia (Discard Site: recreational fishing discards only Provisioning Site: recreational fishing discards and commercial baits) using stable isotope analysis of carbon ( δ 13 C) and nitrogen ( δ 15 N), and Bayesian stable isotope mixing models. Our results indicate that at both sites invertebrates, considered a main part of the natural diet of smooth stingrays, made a limited contribution to the diets of provisioned stingrays, while a benthic teleost fish that is a common recreational catch was the dominant contributor. As the assessed teleost is potentially a natural prey item for smooth stingrays, it remains unclear whether the contribution came from recreational fishing discards or natural foraging. However, due to smooth stingrays’ typically opportunistic foraging strategy, we expected a greater mixture of resources from low to high trophic level prey than was observed. These results suggest that smooth stingrays have either lower reliance on invertebrates as a result of utilizing provisioned resources or higher reliance on teleost fishes than previously thought. Commercial bait products fed to stingrays at the Provisioning Site were not a major contributor to the diets of smooth stingrays, suggesting this activity has a low impact on their nutrition.
Publisher: Elsevier BV
Date: 09-2022
Publisher: Wiley
Date: 17-03-2017
DOI: 10.1111/JFB.13275
Abstract: The internal anatomy of the barbels of the common sawshark Pristiophorus cirratus was examined with light microscopy to clarify their sensory role. No sensory structures such as taste buds (chemoreception), ullae of Lorenzini (electroreception) or free neuromasts (lateral line mechanoreception) could be located in the barbels. The presence of bundles of nerve fibres, however, indicates a tactile function for the barbels. Conveyance of information regarding potentially damaging stimuli (nociception) and temperature (thermoception) cannot be excluded at this stage. It is hypothesized that the barbels are used by P. cirratus to locate prey in both the water column and on the substratum via wake detection and sensing changes in surface texture. The barbels may also be involved in the detection of water currents for rheotaxis. Regression analyses on P. cirratus morphometric data showed that the width of the rostrum at two sections (the barbels and the rostrum tip) does not significantly correlate with total length. The regression analyses also suggested that the barbels of P. cirratus may be lateralised.
Publisher: Springer Science and Business Media LLC
Date: 13-04-2021
DOI: 10.1186/S13054-021-03465-0
Abstract: To determine the frequency of, and factors associated with, death in hospital following ICU discharge to the ward. The Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE study was an international, multicenter, prospective cohort study of patients with severe respiratory failure, conducted across 459 ICUs from 50 countries globally. This study aimed to understand the frequency and factors associated with death in hospital in patients who survived their ICU stay. We examined outcomes in the subpopulation discharged with no limitations of life sustaining treatments (‘treatment limitations’), and the subpopulations with treatment limitations. 2186 (94%) patients with no treatment limitations discharged from ICU survived, while 142 (6%) died in hospital. 118 (61%) of patients with treatment limitations survived while 77 (39%) patients died in hospital. Patients without treatment limitations that died in hospital after ICU discharge were older, more likely to have COPD, immunocompromise or chronic renal failure, less likely to have trauma as a risk factor for ARDS. Patients that died post ICU discharge were less likely to receive neuromuscular blockade, or to receive any adjunctive measure, and had a higher pre- ICU discharge non-pulmonary SOFA score. A similar pattern was seen in patients with treatment limitations that died in hospital following ICU discharge. A significant proportion of patients die in hospital following discharge from ICU, with higher mortality in patients with limitations of life-sustaining treatments in place. Non-survivors had higher systemic illness severity scores at ICU discharge than survivors. Trial Registration : ClinicalTrials.gov NCT02010073 .
Publisher: Springer Science and Business Media LLC
Date: 10-01-2018
Publisher: Elsevier BV
Date: 04-2019
Publisher: Elsevier BV
Date: 05-2020
Publisher: Elsevier BV
Date: 04-2021
Publisher: PeerJ
Date: 25-04-2016
DOI: 10.7717/PEERJ.1960
Abstract: Citizen science can increase the scope of research in the marine environment however, it suffers from necessitating specialized training and simplified methodologies that reduce research output. This paper presents a simplified, novel survey methodology for citizen scientists, which combines GoPro imagery and structure from motion to construct an ortho-corrected 3D model of habitats for analysis. Results using a coral reef habitat were compared to surveys conducted with traditional snorkelling methods for benthic cover, holothurian counts, and coral health. Results were comparable between the two methods, and structure from motion allows the results to be analysed off-site for any chosen visual analysis. The GoPro method outlined in this study is thus an effective tool for citizen science in the marine environment, especially for comparing changes in coral cover or volume over time.
Publisher: Wiley
Date: 12-11-2020
DOI: 10.1111/JFB.14567
Start Date: 2017
End Date: 2018
Funder: Sea World Research and Rescue Foundation
View Funded ActivityStart Date: 2018
End Date: 2020
Funder: Fisheries Research and Development Corporation
View Funded ActivityStart Date: 2018
End Date: 2020
Funder: NSW Department of Primary Industries
View Funded Activity