ORCID Profile
0000-0003-0374-9941
Current Organisations
Flinders University
,
James Cook University
,
Occidental College
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Applied Statistics | Marine and Estuarine Ecology (incl. Marine Ichthyology) | Ecology | Environmental Impact Assessment
Expanding Knowledge in the Biological Sciences | Marine Flora, Fauna and Biodiversity |
Publisher: Wiley
Date: 19-07-2021
Abstract: Identifying the species involved in shark bite incidents is an ongoing challenge but is important to mitigate risk. We developed a s ling protocol to identify shark species from DNA transferred to inanimate objects during bite incidents. To develop and refine the technique, we swabbed shark bite impressions on surfboards and wetsuit neoprene collected under semicontrolled conditions. Methods were tested experimentally and then successfully used to identify the species involved in a real‐world shark bite incident. Thirty‐two of 33 bite impressions yielded sufficient DNA sequences for species identification, producing barcodes from five test species, including dusky, Galapagos, bull, tiger, and white shark. The latter three species collectively account for a majority of shark bites worldwide. Our method successfully identified the species ( Galeocerdo cuvier ) responsible for a fatal shark bite on December 8th, 2020 on the island of Maui, from swab s les collected from the victim's surfboard 49 h after the bite incident. Our experimental results demonstrate that shark species can be accurately identified from transfer DNA recovered from bite impressions on surfboards and wetsuit neoprene. The successful use of our method in the real‐world incident shows great potential for the practicality of this tool. We recommend DNA swabbing as a routine part of the forensic analysis of shark bites to help identify the species involved in human‐shark interactions.
Publisher: PeerJ
Date: 31-08-2018
DOI: 10.7717/PEERJ.5554
Abstract: The number of shark-human interactions and shark bites per capita has been increasing since the 1980s, leading to a rise in measures developed to mitigate the risk of shark bites. Yet many of the products commercially available for personal protection have not been scientifically tested, potentially providing an exaggerated sense of security to the people using them. We tested five personal shark deterrents developed for surfers ( Shark Shield Pty Ltd [ Ocean Guardian ] Freedom+ Surf, Rpela, SharkBanz bracelet, SharkBanz surf leash, and Chillax Wax ) by comparing the percentage of baits taken, distance to the bait, number of passes, and whether a shark reaction could be observed. We did a total of 297 successful trials at the Neptune Islands Group Marine Park in South Australia, during which 44 different white sharks ( Carcharodon carcharias ) interacted with the bait, making a total of 1413 passes. The effectiveness of the deterrents was variable, with the Freedom+ Surf affecting shark behaviour the most and reducing the percentage of bait taken from 96% (relative to the control board) to 40%. The mean distance of sharks to the board increased from 1.6 ± 0.1 m (control board) to 2.6 ± 0.1 m when the Freedom Surf+ was active. The other deterrents had limited or no measureable effect on white shark behavour. Based on our power analyses, the smallest effect size that could be reliably detected was ∼15%, which for the first time provides information about the effect size that a deterrent study like ours can reliably detect. Our study shows that deterrents based on similar principles—overwhelming a shark’s electroreceptors (the ullae of Lorenzini) with electrical pulses—differ in their efficacy, reinforcing the need to test each product independently. Our results will allow private and government agencies and the public to make informed decisions about the use and suitability of these five products.
Publisher: Frontiers Media SA
Date: 17-12-2018
Publisher: Wiley
Date: 19-01-2021
DOI: 10.1111/CONL.12788
Abstract: Wildlife tourism is growing in popularity, ersity of target species, and type of tours. This presents difficulties for management policy that must balance the complex trade‐offs between conservation, animal welfare, and pragmatic concerns for tourist satisfaction and economic value. Here, we provide a widely applicable, multidisciplinary framework to assess the impacts of wildlife tourism focusing on industry tractability, socioeconomic values, and their effects on conservation, animal welfare, and ecosystem impacts. The framework accommodates and quantifies the complexity of factors influencing wildlife tourism management, including direct and indirect effects on target and nontarget species, and identifies priorities for future biological, socioeconomic, and cultural heritage research. When applied to white shark cage‐ ing as a case study, the output demonstrates the utility of the framework for researchers, managers, and policy makers, and highlights the benefits of undertaking the assessment as an inclusive workshop to facilitate a more multidisciplinary assessment of wildlife tourism industries. The use of a universally applicable assessment framework will enable the identification of relevant factors to account for when managing wildlife tourism, provide an inventory of current knowledge, identify research needs, and semiquantitatively compare categories and target and nontarget species, leading to improved conservation outcomes for species and ecosystems.
Publisher: Frontiers Media SA
Date: 24-11-2017
Publisher: Elsevier BV
Date: 03-2022
DOI: 10.1016/J.JHAZMAT.2021.127956
Abstract: Large marine predators exhibit high concentrations of mercury (Hg) as neurotoxic methylmercury, and the potential impacts of global change on Hg contamination in these species remain highly debated. Current contaminant model predictions do not account for intraspecific variability in Hg exposure and may fail to reflect the ersity of future Hg levels among conspecific populations or in iduals, especially for top predators displaying a wide range of ecological traits. Here, we used Hg isotopic compositions to show that Hg exposure sources varied significantly between and within three populations of white sharks (Carcharodon carcharias) with contrasting ecology: the north-eastern Pacific, eastern Australasian, and south-western Australasian populations. Through Δ
Publisher: Informa UK Limited
Date: 16-06-2021
Publisher: Springer Science and Business Media LLC
Date: 03-06-2021
DOI: 10.1038/S41598-021-89903-Z
Abstract: The Cookiecutter shark ( Isistius brasiliensis ) is an ectoparasitic, mesopelagic shark that is known for removing plugs of tissue from larger prey, including teleosts, chondrichthyans, cephalopods, and marine mammals. Although this species is widely distributed throughout the world’s tropical and subtropical oceanic waters, like many deep-water species, it remains very poorly understood due to its mesopelagic distribution. We used a suite of biochemical tracers, including stable isotope analysis (SIA), fatty acid analysis (FAA), and environmental DNA (eDNA), to investigate the trophic ecology of this species in the Central Pacific around Hawaii. We found that large epipelagic prey constituted a relatively minor part of the overall diet. Surprisingly, small micronektonic and forage species (meso- and epipelagic) are the most important prey group for Cookiecutter sharks across the studied size range (17–43 cm total length), with larger mesopelagic species or species that exhibit diel vertical migration also being important prey. These results were consistent across all the tracer techniques employed. Our results indicate that Cookiecutter sharks play a unique role in pelagic food webs, feeding on prey ranging from the largest apex predators to small, low trophic level species, in particular those that overlap with the depth distribution of the sharks throughout the diel cycle. We also found evidence of a potential shift in diet and/or habitat with size and season. Environmental DNA metabarcoding revealed new prey items for Cookiecutter sharks while also demonstrating that eDNA can be used to identify recent prey in stomachs frozen for extended periods. Integrating across chemical tracers is a powerful tool for investigating the ecology of elusive and difficult to study species, such as meso- and bathypelagic chondrichthyans, and can increase the amount of information gained from small s le sizes. Better resolving the foraging ecology of these mesopelagic predators is critical for effective conservation and management of these taxa and ecosystems, which are intrinsically vulnerable to overfishing and exploitation.
Publisher: Elsevier BV
Date: 12-2019
Publisher: Wiley
Date: 21-04-2019
Publisher: The Royal Society
Date: 05-2019
DOI: 10.1098/RSOS.190456
Abstract: Visual estimates have been used extensively to determine the length of large organisms that are logistically challenging to measure. However, there has been little effort to quantify the accuracy or validity of this technique despite inaccurate size estimates leading to incorrect population assessments and misinformed management strategies. Here, we compared visually estimated total length measurements of white sharks, Carcharodon carcharias , during cage- ing operations with measurements obtained from stereo-video cameras and assessed the accuracy of those estimates in relation to suspected biases (shark size, and observer experience and gender) using generalized linear mixed-models and linear regressions. Observer experience on board cage- ing vessels had the greatest effect on the accuracy of visual length estimates, with scientists being more accurate (mean accuracy ± standard error: 23.0 ± 16.5 cm) than crew (39.9 ± 33.8 cm) and passengers (49.4 ± 38.5 cm). Observer gender and shark size had no impact on the overall accuracy of visual length estimates, but passengers overestimated sharks less than 3 m and underestimated sharks greater than 3 m. Our findings show that experience measuring animals is the most substantial driver of accurate visual length estimates regardless of the amount of exposure to the species being measured. Scientists were most accurate, even though crew observe white sharks more frequently. Our results show that visual length estimates are not impacted by shark size and are a valid measurement tool for many aspects of C. carcharias research, provided they come from people who have previously been involved in measuring animals, i.e. scientists .
Publisher: Elsevier BV
Date: 09-2016
DOI: 10.1016/J.TOXICON.2016.06.007
Abstract: Ciguatoxins (CTXs) produced by benthic Gambierdiscus dinoflagellates, readily biotransform and bioaccumulate in food chains ultimately bioconcentrating in high-order, carnivorous marine species. Certain shark species, often feeding at, or near the top of the food-chain have the ability to bioaccumulate a suite of toxins, from both anthropogenic and algal sources. As such, these apex predators are likely sinks for CTXs. This assumption, in conjunction with anecdotal knowledge of poisoning incidents, several non-specific feeding trials whereby various terrestrial animals were fed suspect fish flesh, and a single incident in Madagascar in 1994, have resulted in the widespread acceptance that sharks may accumulate CTXs. This prompted a study to investigate original claims within the literature, as well as investigate CTX bioaccumulation in the muscle and liver of 22 in idual sharks from nine species, across four locations along the east coast of Australia. Utilizing an updated ciguatoxin extraction method with HPLC-MS/MS, we were unable to detect P-CTX-1, P-CTX-2 or P-CTX-3, the three primary CTX congeners, in muscle or liver s les. We propose four theories to address this finding: (1) to date, methods have been optimized for teleost species and may not be appropriate for elasmobranchs, or the CTXs may be below the limit of detection (2) CTX may be biotransformed into elasmobranch-specific congeners as a result of unique metabolic properties (3) 22 in iduals may be an inadequate s le size given the rare occurrence of high-order ciguatoxic organisms and potential for CTX depuration and (4) the ephemeral nature and inconsistent toxin profiles of Gambierdiscus blooms may have undermined our classifications of certain areas as CTX hotspots. These results, in combination with the lack of clarity within the literature, suggest that ciguatoxin bioaccumulation in sharks remains elusive, and warrants further investigation to determine the dynamics of toxin production, accumulation and transformation throughout the entire food-web.
Publisher: Elsevier BV
Date: 2020
Publisher: MDPI AG
Date: 05-09-2022
DOI: 10.3390/V14091969
Abstract: The epidermal microbiome is a critical element of marine organismal immunity, but the epidermal virome of marine organisms remains largely unexplored. The epidermis of sharks represents a unique viromic ecosystem. Sharks secrete a thin layer of mucus which harbors a erse microbiome, while their hydrodynamic dermal denticles simultaneously repel environmental microbes. Here, we s led the virome from the epidermis of three shark species in the family Carcharhinidae: the genetically and morphologically similar Carcharhinus obscurus (n = 6) and Carcharhinus galapagensis (n = 10) and the outgroup Galeocerdo cuvier (n = 15). Virome taxonomy was characterized using shotgun metagenomics and compared with a suite of multivariate analyses. All three sharks retain species-specific but highly similar epidermal viromes dominated by uncharacterized bacteriophages which vary slightly in proportional abundance within and among shark species. Intraspecific variation was lower among C. galapagensis than among C. obscurus and G. cuvier. Using both the annotated and unannotated reads, we were able to determine that the Carcharhinus galapagensis viromes were more similar to that of G. cuvier than they were to that of C. obscurus, suggesting that behavioral niche may be a more prominent driver of virome than host phylogeny.
Publisher: Center for Open Science
Date: 15-04-2019
Abstract: Research teams collect & million biological s les annually, the majority of which are subs led for targeted analysis. The remaining s le, often including a number of unused organs, is then able to be repurposed for additional studies. However, the absence of a systematic method for scientists to source these unused s les results in wasted s les, organisms and opportunities for research as scientists undertake redundant s ling regimes. As such, ‘Otlet’, a global online database, was established to overcome the challenges of sourcing scientific research s les from colleagues. The platform allows the users to 1) upload a record of their unused s les for collaboration, 2) search the database of existing s les from other scientific users and request them directly and, 3) post a request for s les onto a searchable community board. The platform facilitates communication between research teams across different locations, taxa and expertise to foster novel collaborations while accelerating scientific output.Otlet’s newly constructed platform is an important tool for biological scientists of all disciplines to efficiently communicate and source research material. Membership is freely available for scientific use by researchers from universities, government agencies, museums, private consulting and NGOs.
Publisher: Elsevier BV
Date: 12-2015
DOI: 10.1016/J.TOXICON.2015.10.021
Abstract: Ciguatera fish poisoning is a debilitating human neuro-intoxication caused by consumption of tropical marine organisms, contaminated with bioaccumulated ciguatoxins (CTXs). The growing number of cases coupled with the high toxicity of CTXs makes their reliable detection and quantification of paramount importance. Three commonly occurring ciguatoxins, P-CTX-1, 2 and 3 from five different ciguatoxic Spanish mackerel (Scomberomorus commerson), were used to assess the effectiveness of different extraction techniques: homogenization (high powered blending vs. ultrasonication) C-18 column sizes (500 mg vs. 900 mg) and a novel HILIC SPE cleanup. Despite minor differences, blending and sonication proved equally effective. Larger 900 mg columns offered a greater extraction efficiency, increasing detected P-CTX-1 by 37% (P < 0.001). The newly adapted cleanup was highly effective at reducing co-eluting phospholipids thereby reducing matrix effects and increasing detectable CTXs by HPLC-MS/MS. Silica cleanup extraction efficiencies were also compared between the highly effective and validated ciguatoxin rapid extraction method (CREM) and current best practice extraction method employed by Queensland Health (QH). Overall, the QH protocol proved more effective, especially when paired with the newly adapted cleanup, as this increased the amount of extracted P-CTX-1 by 46% (P < 0.01), P-CTX-2 by 10% and P-CTX-3 by 71% (P = 0.001). This study suggests the QH protocol utilizing a 900 mg C-18 column and newly adapted HILIC SPE cleanup was most effective at extracting P-CTX-1, -2, -3. Specifically P-CTX-1, the primary ciguatoxin congener of concern due to its extremely high potency and an ability to cause CFP at 0.1 μg/kg following consumption of carnivorous fish flesh. Despite being more time intensive (an additional 85 min per batch of 12 s les), this will be especially effective for assessing lower toxin burdens, which may be near the limit of detection.
Publisher: Wiley
Date: 16-11-2020
DOI: 10.1111/JFB.14602
Publisher: Elsevier BV
Date: 12-2018
Publisher: Elsevier BV
Date: 10-2014
Publisher: Wiley
Date: 30-11-2022
DOI: 10.1002/ECY.3888
Abstract: Lipid and fatty acid datasets are commonly used to assess the nutritional composition of organisms, trophic ecology, and ecosystem dynamics. Lipids and their fatty acid constituents are essential nutrients to all forms of life because they contribute to biological processes such as energy flow and metabolism. Assessment of total lipids in tissues of organisms provides information on energy allocation and life‐history strategies and can be an indicator of nutritional condition. The analysis of an organism's fatty acids is a widely used technique for assessing nutrient and energy transfer, and dietary interactions in food webs. Although there have been many published regional studies that assessed lipid and fatty acid compositions, many only report the mean values of the most abundant fatty acids. There are limited in idual records available for wider use in intercomparison or macro‐scale studies. This dataset consists of 4856 records of in idual and pooled s les of at least 470 different marine consumer species s led from tropical, temperate, and polar regions around Australia and in the Southern, Indian, and Pacific Oceans from 1989 to 2018. This includes data for a erse range of taxa (zooplankton, fish, cephalopods, chondrichthyans, and marine mammals), size ranges (0.02 cm to ~13 m), and that cover a broad range of trophic positions (2.0–4.6). When known, we provide a record of species name, date of s ling, s ling location, body size, relative (%) measurements of tissue‐specific total lipid content and abundant fatty acids, and absolute content (mg 100 g −1 tissue) of eicosapentaenoic acid (EPA, 20:5n3) and docosahexaenoic acid (DHA, 22:6n3) as important long‐chain (≥C 20 ) polyunsaturated omega‐3 fatty acids. These records form a solid basis for comparative studies that will facilitate a broad understanding of the spatial and temporal distribution of marine lipids globally. The dataset also provides reference data for future dietary assessments of marine predators and model assessments of potential impacts of climate change on the availability of marine lipids and fatty acids. There are 480 data records within our data file for which the providers have requested that permission for reuse be granted, with the likely condition that they are included as a coauthor on the reporting of the dataset. Records with this condition are indicated by a “yes” under “Conditions_of_data_use” in Data S1: Marineconsumer_FAdata.csv (see Table 2 in Metadata S1 for more details). For all other data records marked as “No” under “Conditions_of_data_use,” there are no copyright restrictions for research and/or teaching purposes. We request that users acknowledge use of the data in publications, research proposals, websites, and other outlets via formal citation of this work and original data sources as applicable.
Start Date: 12-2022
End Date: 12-2025
Amount: $432,447.00
Funder: Australian Research Council
View Funded Activity