ORCID Profile
0000-0003-4588-7955
Current Organisation
James Cook University
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.
Publisher: Inter-Research Science Center
Date: 2004
DOI: 10.3354/MEPS276281
Publisher: Elsevier BV
Date: 05-2020
Publisher: Informa UK Limited
Date: 03-2013
Publisher: Inter-Research Science Center
Date: 26-05-2010
DOI: 10.3354/ESR00279
Publisher: CSIRO Publishing
Date: 2016
DOI: 10.1071/MF14117
Abstract: Increased suspended-sediment concentrations (SS) in rivers can affect aquatic respiration in riverine fauna by impairing respiratory function. Bimodally respiring freshwater turtles are likely to be sensitive to changes in SS because increased concentrations may affect their ability to aquatically respire. However, the impact of SS on the ing behaviour of bimodally respiring freshwater turtles has not been formally investigated. To test this, we examined the influence of dissolved oxygen (DO) saturation (25%, 100%) and temperature (17°C, 25°C) on the ing behaviour of Elseya irwini under clear (0mgL–1) and turbid (79mgL–1) conditions. We hypothesised that low temperature and high DO % saturation would increase e duration and that high SS would negate the effect of DO, decreasing e duration under highly oxygenated conditions. Our data demonstrated that increased SS significantly reduced mean e duration by 73% (97.4±10.1min in 0mgL–1 trials v. 26.4±3.2min in 79mgL–1 trials) under conditions of low temperature (17°C) and high DO % saturation (100%) only. Increased SS directly affects the utilisation of DO by this species, so as to extend submergence times (aquatic respiration) under optimal conditions, raising concerns about the effect of SS on the persistence of populations of physiologically specialised freshwater turtles.
Publisher: Elsevier BV
Date: 06-2000
Publisher: Elsevier BV
Date: 02-2003
DOI: 10.1016/S0016-6480(02)00624-X
Abstract: We investigated three aspects of potential interrenal regulation of reproduction in female green sea turtles, Chelonia mydas. First, seasonal trends in plasma catecholamines were examined from female C. mydas at different stages of their reproductive cycles. Second, variation in catecholamine levels during a nesting season were analysed in relation to restraint time, and ecological variables such as nesting habitat, body size, and reproductive investment. Third, catecholamine and corticosterone (CORT) induced lipolysis was investigated with adipose tissue collected from gravid green turtles, using in vitro incubations. Plasma epinephrine (EPI) was lowest in non-vitellogenic (1.55 +/- 0.26 ng/ml) and post-breeding (1.57 +/- 0.22 ng/ml) females, and highest in courting females (2.87 +/- 0.28). Concentrations of norepinephrine (NE) and EPI were relatively constant throughout a nesting season, and not significantly related to restraint time, reproductive investment or nesting habitat. In vitro concentrations of CORT (>3 ng/ml) and NE (2 ng/ml) induced significant release of glycerol after 6h of incubation. Epinephrine tended to induce an antilipolytic affect at low concentrations (0.25 ng/ml) and a net lipolytic response at higher concentrations (>1 ng/ml). Our data suggest that EPI may play a role in regulating body condition during vitellogenesis, and maintaining energy stores during prolonged aphagia during courtship and nesting in female green sea turtles. Furthermore, we provide preliminary evidence that suggests that catecholamine production may be either down regulated or de-sensitised in gravid female C. mydas.
Publisher: Wiley
Date: 04-12-2018
DOI: 10.1111/GCB.14519
Publisher: Inter-Research Science Center
Date: 03-02-2016
DOI: 10.3354/MEPS11521
Publisher: Elsevier BV
Date: 04-2016
Publisher: CSIRO Publishing
Date: 2014
DOI: 10.1071/WR14155
Abstract: Context Numerous studies show that artificial light disrupts the sea-finding ability of marine turtle hatchlings. Yet very little has been published regarding sea-finding for flatback turtles. Given the current industrialisation of Australia’s coastline, and the large potential for disruption posed by industrial light, this study is a timely investigation into sea-finding behaviour of flatback turtle hatchlings. Aims We investigate sea-finding by flatback turtle hatchlings in relation to ambient light present in areas of planned or ongoing industrial development, and evaluate the fan and arena-based methods that are frequently used for quantifying hatchling dispersion. Methods Using a combination of methods, we assessed the angular range and directional preference of sea-finding hatchlings at two key flatback turtle rookeries, Peak and Curtis Islands, during January–February 2012 and 2013, and at Curtis Island in January 2014. Relative light levels at each site were measured using an Optec SSP-3 stellar photometer, and moon phase, moon stage and cloud cover were also recorded. Key results We found no evidence of impaired hatchling orientation, and observed very low levels of light at Peak Island. However, at Curtis Island, hatchlings displayed reduced sea-finding ability, with light horizons from the direction of nearby industry significantly brighter than from other directions. The sea-finding disruption observed at Curtis Island was less pronounced in the presence of moonlight. Conclusions The reduced sea-finding ability of Curtis Island hatchlings was likely due to both altered light horizons from nearby industry, as well as beach topography. Both methods of assessing hatchling orientation have benefits and limitations. We suggest that fan-based methods, combined with strategically placed arenas, would provide the best data for accurately assessing hatchling sea-finding. Implications Sky glow produced by large-scale industrial development appears detrimental to sea-finding by flatback turtle hatchlings. As development continues around Australia’s coastline, we strongly recommend continued monitoring of lighting impacts at adjacent turtle nesting beaches. We also advise rigorous management of industrial lighting, which considers cumulative light levels in regions of multiple light producers, as well as moon phase, moon-stage, cloud cover and time of hatchling emergence. All these factors affect the likelihood of disrupted hatchling sea-finding behaviour at nesting beaches exposed to artificial light-glow, industrial or otherwise.
Publisher: Springer Science and Business Media LLC
Date: 24-06-2014
DOI: 10.1007/S00267-014-0308-9
Abstract: Artificial lighting along coastlines poses a significant threat to marine turtles due to the importance of light for their natural orientation at the nesting beach. Effective lighting management requires widespread support and participation, yet engaging the public with light reduction initiatives is difficult because benefits associated with artificial lighting are deeply entrenched within modern society. We present a case study from Queensland, Australia, where an active light-glow reduction c aign has been in place since 2008 to protect nesting turtles. Semi-structured questionnaires explored community beliefs about reducing light and evaluated the potential for using persuasive communication techniques based on the theory of planned behavior (TPB) to increase engagement with light reduction. Respondents (n = 352) had moderate to strong intentions to reduce light. TPB variables explained a significant proportion of variance in intention (multiple regression: R (2) = 0.54-0.69, P < 0.001), but adding a personal norm variable improved the model (R (2) = 0.73-0.79, P < 0.001). Significant differences in belief strength between c aign compliers and non-compliers suggest that targeting the beliefs reducing light leads to "increased protection of local turtles" (P < 0.01) and/or "benefits to the local economy" (P < 0.05), in combination with an appeal to personal norms, would produce the strongest persuasion potential for future communications. Selective legislation and commitment strategies may be further useful strategies to increase community light reduction. As artificial light continues to gain attention as a pollutant, our methods and findings will be of interest to anyone needing to manage public artificial lighting.
Publisher: Springer Science and Business Media LLC
Date: 08-2002
DOI: 10.1007/S00360-002-0271-2
Abstract: Reproductive data from southern Queensland indicate that vitellogenesis in female Chelonia mydas takes approximately 8 months and is followed by a migration to a breeding area. At Heron Island, females lay multiple clutches over approximately 3 months. To investigate how females mobilise and store lipid during the breeding season we collected plasma, yolk, and fat tissue s les from females at a variety of stages during the nesting season. In breeding females, concentrations of plasma triglyceride increased seasonally. They reached peak concentrations during vitellogenesis and courtship, remained high throughout the nesting season, and then declined to a nadir after the last clutch. Plasma protein concentration increased throughout the breeding season, peaking following the last clutch for the season. Yolk lipids were highest during courtship and were similar throughout the nesting season, suggesting that uptake of lipid by ovarian follicles is completed prior to the beginning of the nesting season. Plasma triglyceride decreases in females with prolonged periods of unsuccessful nesting, and total lipid levels in adipose tissue and follicle yolks were significantly lower in atretic females. It appears that: (1) endogenous energy reserves can be reduced by stochastic environmental events (such as those reducing nesting success), and (2) a metabolic shift signalling the end of the nesting season is characterised by a drop in plasma triglycerides and slight increase in total plasma protein.
Publisher: Wiley
Date: 12-2010
Publisher: Elsevier BV
Date: 11-2016
Publisher: Elsevier
Date: 2019
Publisher: Elsevier BV
Date: 09-2019
DOI: 10.1016/J.ENVPOL.2019.06.031
Abstract: Plastic pollution in the marine environment is a pervasive and increasing threat to global bio ersity. Prioritising management actions that target marine plastic pollution require spatial information on the dispersal and settlement of plastics from both local and external sources. However, there is a mismatch between the scale of most plastic dispersal studies (regional, national and global) and the scale relevant to management action (local). We use a fine-resolution hydrodynamic model to predict the potential exposure of coastal habitats and species (mangroves, coral reefs and marine turtles) to plastic pollution at the local scale of a management region (the 1,700 km
Publisher: Elsevier BV
Date: 02-2017
Publisher: The Royal Society
Date: 23-12-2008
Publisher: Elsevier BV
Date: 12-2015
Publisher: Wiley
Date: 28-10-2021
Publisher: Inter-Research Science Center
Date: 21-03-2016
DOI: 10.3354/MEPS11632
Publisher: Elsevier BV
Date: 03-2009
Publisher: Informa UK Limited
Date: 24-10-2016
Publisher: Frontiers Media SA
Date: 03-07-2018
Publisher: Springer Science and Business Media LLC
Date: 2016
Publisher: Elsevier BV
Date: 12-2007
Publisher: CSIRO Publishing
Date: 2008
DOI: 10.1071/WR07087
Abstract: In 2004 the Australian Government implemented a revised zone-based management plan for the Great Barrier Reef World Heritage Area to increase protection of representative areas while minimising the impacts to the economic viability of important industries. In this study we evaluated the current zoning plan for its capacity to protect marine turtles from commercial trawling and netting activities at nesting sites and at inshore and offshore foraging areas to assess whether the Great Barrier Reef Marine Park Authority met their obligations under the Representative Areas Program (RAP). We found that protection from commercial fisheries increased within 5- and 10-km buffer zones of all very-high, high- and medium-priority nesting sites that were previously less than 100% protected. However, three very-high-priority sites and six high-priority sites remain less than 100% protected out to 5 km, falling short of the objectives of the RAP. There were variable increases in protection at foraging areas however, each of them increased in the proportion of area protected from commercial fishing, fulfilling the objectives of the RAP. By using a broader-scale fisheries by-catch dataset as a proxy for turtle abundance we found that improvements in protection are not species-specific and can be attributed to the step-wise increases in protection since the mid 1990s.
Publisher: Elsevier BV
Date: 03-2015
Publisher: Springer Science and Business Media LLC
Date: 19-08-2005
Publisher: Wiley
Date: 02-07-2009
DOI: 10.1002/AQC.1057
Publisher: Public Library of Science (PLoS)
Date: 17-12-2010
Publisher: Springer Science and Business Media LLC
Date: 23-05-2017
Publisher: CSIRO Publishing
Date: 2005
DOI: 10.1071/ZO04061
Abstract: We investigated plasma hormone profiles of corticosterone in green turtles (Chelonia mydas) in response to a capture stress protocol. Further, we examined whether age class and sex were covariates associated with variation in both basal corticosterone levels and the adrenocortical stress response of non-breeding green turtles. Green turtles responded to the capture stress protocol by significantly increasing plasma levels of corticosterone over an eight-hour period. Further, there was a significant effect of age class on the capacity for green turtles to produce corticosterone in response to a capture stressor, with juvenile green turtles having higher basal levels of corticosterone and producing significantly more corticosterone in response to capture stress than non-breeding adult turtles. In contrast there was no significant sex difference in the corticosterone stress response of green turtles irrespective of age class. In summary, green turtles exhibited an adrenocortical response to a capture stress protocol. This response was significantly associated with different age classes, perhaps suggesting that the response is increased in juvenile turtles to offset the reduced probability of survival consistent with this more vulnerable age class.
Publisher: PeerJ
Date: 28-09-2018
DOI: 10.7717/PEERJ.5651
Abstract: A solid understanding of the spatial ecology of green turtles ( Chelonia mydas ) is fundamental to their effective conservation. Yet this species, like many marine migratory species, is challenging to monitor and manage because they utilise a variety of habitats that span wide spatio-temporal scales. To further elucidate the connectivity between green turtle rookeries and foraging populations, we sequenced the mtDNA control region of 278 turtles across three foraging sites from the northern Great Barrier Reef (GBR) spanning more than 330 km: Cockle Bay, Green Island and Low Isles. This was performed with a newly developed assay, which targets a longer fragment of mtDNA than previous studies. We used a mixed stock analysis (MSA), which utilises genetic data to estimate the relative proportion of genetically distinct breeding populations found at a given foraging ground. Haplotype and nucleotide ersity was also assessed. A total of 35 haplotypes were identified across all sites, 13 of which had not been found previously in any rookery. The MSA showed that the northern GBR (nGBR), Coral Sea (CS), southern GBR (sGBR) and New Caledonia (NC) stocks supplied the bulk of the turtles at all three sites, with small contributions from other rookeries in the region. Stock contribution shifted gradually from north to south, although sGBR/CS stock dominated at all three sites. The major change in composition occured between Cockle Bay and Low Isles. Our findings, together with other recent studies in this field, show that stock composition shifts with latitude as a natural progression along a coastal gradient. This phenomenon is likely to be the result of ocean currents influencing both post-hatchling dispersal and subsequent juvenile recruitment to erse coastal foraging sites.
Publisher: Wiley
Date: 11-05-2022
DOI: 10.1111/COBI.13724
Abstract: Wildlife health assessments help identify populations at risk of starvation, disease, and decline from anthropogenic impacts on natural habitats. We conducted an overview of available health assessment studies in noncaptive vertebrates and devised a framework to strategically integrate health assessments in population monitoring. Using a systematic approach, we performed a thorough assessment of studies examining multiple health parameters of noncaptive vertebrate species from 1982 to 2020 ( n = 261 studies). We quantified trends in study design and diagnostic methods across taxa with generalized linear models, bibliometric analyses, and visual representations of study location versus bio ersity hotspots. Only 35% of studies involved international or cross‐border collaboration. Countries with both high and threatened bio ersity were greatly underrepresented. Species that were not listed as threatened on the International Union for Conservation of Nature Red List represented 49% of assessed species, a trend likely associated with the regional focus of most studies. We strongly suggest following wildlife health assessment protocols when planning a study and using statistically adequate s le sizes for studies establishing reference ranges. Across all taxa blood analysis (89%), body composition assessments (81%), physical examination (72%), and fecal analyses (24% of studies) were the most common methods. A conceptual framework to improve design and standardize wildlife health assessments includes guidelines on the experimental design, data acquisition and analysis, and species conservation planning and management implications. Integrating a physiological and ecological understanding of species resilience toward threatening processes will enable informed decision making regarding the conservation of threatened species.
Publisher: Wiley
Date: 24-01-2014
DOI: 10.1111/GCB.12503
Abstract: Artificial light at night poses a significant threat to multiple taxa across the globe. In coastal regions, artificial lighting close to marine turtle nesting beaches is disruptive to their breeding success. Prioritizing effective management of light pollution requires an understanding of how the light exposure of nesting areas changes over time in response to changing temporal and spatial distributions of coastal development. We analyzed multitemporal, satellite night-light data, in combination with linear mixed model analysis, to determine broadscale changes in artificial light exposure at Australian marine turtle nesting areas between 1993 and 2010. We found seven marine turtle management units (MU), from five species, have experienced significant increases in light exposure over time, with flatback turtles nesting in east Australia experiencing the fastest increases. The remaining 12 MUs showed no significant change in light exposure. Unchanging MUs included those previously identified as having high exposure to light pollution (located in western Australia and southern Queensland), indicating that turtles in these areas have been potentially exposed to high light levels since at least the early nineties. At a finer geographic scale (within-MU), nine MUs contained nesting areas with significant increases in light exposure. These nesting areas predominantly occurred close to heavily industrialized coastal areas, thus emphasizing the importance of rigorous light management in industry. Within all MUs, nesting areas existed where light levels were extremely low and/or had not significantly increased since 1993. With continued coastal development, nesting females may shift to these darker/unchanging 'buffer' areas in the future. This is valuable information that informs our understanding of the capacity and resilience of marine turtles faced with coastal development: an understanding that is essential for effective marine turtle conservation.
Publisher: Inter-Research Science Center
Date: 07-03-2016
DOI: 10.3354/ESR00725
Publisher: Society for the Study of Amphibians and Reptiles
Date: 12-2016
DOI: 10.1670/15-026
Publisher: Springer Science and Business Media LLC
Date: 16-08-2019
Publisher: Wiley
Date: 08-07-2011
Publisher: Inter-Research Science Center
Date: 29-12-2016
DOI: 10.3354/MEPS11972
Publisher: Elsevier BV
Date: 02-2014
DOI: 10.1016/J.MARPOLBUL.2013.12.047
Abstract: Efforts to curb pollution in the marine environment are covered by national and international legislation, yet weather balloons are released into the environment with no salvage agenda. Here, we assess impacts associated with weather balloons in the Great Barrier Reef World Heritage Area (GBRWHA). We use modeling to assess the probability of ocean endpoints for released weather balloons and predict pathways post-release. In addition, we use 21 months of data from beach cleanup events to validate our results and assess the abundance and frequency of weather balloon fragments in the GBRWHA. We found between 65% and 70% of balloons land in the ocean and ocean currents largely determine final endpoints. Beach cleanup data revealed 2460 weather balloon fragments were recovered from 24 sites within the GBRWHA. This is the first attempt to quantify this problem and these data will add support to a much-needed mitigation strategy for weather balloon waste.
Publisher: Inter-Research Science Center
Date: 21-06-2012
DOI: 10.3354/MEPS09816
Publisher: Springer Science and Business Media LLC
Date: 10-2006
Publisher: Inter-Research Science Center
Date: 28-09-2018
DOI: 10.3354/ESR00916
Publisher: Elsevier BV
Date: 10-2015
Publisher: Chelonian Conservation and Biology Journal
Date: 18-12-2018
DOI: 10.2744/CCB-1276.1
Publisher: Wiley
Date: 24-11-2017
DOI: 10.1111/CONL.12324
Publisher: Public Library of Science (PLoS)
Date: 28-09-2011
Publisher: Elsevier BV
Date: 12-2015
Publisher: Springer Science and Business Media LLC
Date: 18-11-2012
Publisher: Cambridge University Press (CUP)
Date: 23-04-2020
Publisher: Public Library of Science (PLoS)
Date: 03-06-2014
Publisher: Elsevier BV
Date: 05-2019
DOI: 10.1016/J.TREE.2019.01.009
Abstract: There have been efforts around the globe to track in iduals of many marine species and assess their movements and distribution, with the putative goal of supporting their conservation and management. Determining whether, and how, tracking data have been successfully applied to address real-world conservation issues is, however, difficult. Here, we compile a broad range of case studies from erse marine taxa to show how tracking data have helped inform conservation policy and management, including reductions in fisheries bycatch and vessel strikes, and the design and administration of marine protected areas and important habitats. Using these ex les, we highlight pathways through which the past and future investment in collecting animal tracking data might be better used to achieve tangible conservation benefits.
Publisher: Wiley
Date: 11-2016
DOI: 10.1002/ECS2.1551
Publisher: Inter-Research Science Center
Date: 13-10-2016
DOI: 10.3354/ESR00755
Publisher: Wiley
Date: 26-12-2019
Abstract: Patterns of animal movement associated with foraging lie at the heart of many ecological studies and often animals face decisions of staying in an environment they know versus relocating to new sites. The lack of knowledge of new foraging sites means there is risk associated with a decision to relocate (e.g. poor foraging) as well as a potential benefit (e.g. improved foraging). Using a unique long-term satellite tracking dataset for several sea turtle species, combined with capture-mark-recapture data extending over 50 years, we show how, across species, in iduals generally maintain tight fidelity to specific foraging sites after extended (up to almost 10,000 km) migration to and from distant breeding sites as well as across many decades. Migrating in iduals often travelled through suitable foraging areas en route to their 'home' site and so extended their journeys to maintain foraging site fidelity. We explore the likely mechanistic underpinnings of this trait, which is also seen in some migrating birds, and suggest that in iduals will forgo areas of suitable forage encountered en route during migration when they have poor knowledge of the long-term suitability of those sites, making relocation to those sites risky.
Publisher: Inter-Research Science Center
Date: 19-11-2009
DOI: 10.3354/ESR00233
Publisher: Elsevier BV
Date: 07-2019
DOI: 10.1016/J.MARPOLBUL.2019.04.070
Abstract: Land-based sources contribute approximately 80% of anthropogenic debris in marine environments. A main pathway is believed to be rivers and storm-water systems, yet this input is rarely quantified. We aimed to quantify the abundance of land-based debris entering a river system through storm drains in an urban area of tropical Australia. To account for seasonal variability, debris was quantified pre, post and during the wet season from 2014 to 2017. Plastic items within the river were compared to those in adjacent parks to assess similarities in debris composition. A total of 27,943 items were collected (92% plastic). Debris loads in the post-wet seasons were significantly higher than the wet-season. Furthermore, variability in the portion of debris found in nearby parks compared to the river suggests that factors other than rainfall, play a role in debris abundance. These results can be used to identify targeted management strategies to reduce debris loads.
Publisher: CSIRO Publishing
Date: 2017
DOI: 10.1071/WR16133
Abstract: Context Sound understanding of temporal changes in the abundance of wildlife species is required for assessing their status and for effective conservation and management. In New Caledonia, a single baseline aerial survey of dugongs in 2003 estimated a population of 2026 (± 553 s.e.) in iduals. A second, similar survey in 2008 produced a lower estimate of 606 (± 200 s.e.) in iduals, leading to concerns that the dugong population was experiencing a decline. Aims This study used data collected from additional aerial surveys with the aim of updating information on the current size of the dugong population in New Caledonia and investigating the drivers of change in the estimates. Methods Four additional surveys were conducted: one in each of the cool (June) and warm (November) seasons of 2011 and 2012 around the main Island of New Caledonia. Dugong relative abundance and density were calculated and compared among survey years and survey regions. Drivers of change in the dugong population size were then investigated. Key results The abundance estimates obtained from our four surveys ranged from 649 (± 195 s.e.) to 1227 (± 296 s.e.) dugongs. These new results were not significantly different to the 2008 estimate but were significantly lower than the 2003 estimate. There was no significant variation in the proportion of calves throughout the entire time series of surveys. Conclusions The dugong population of New Caledonia was relatively stable between 2008 and 2012. We could not find sufficient evidence to show whether the discrepancy between 2003 and the remainder of the time series is due to a real decline in the population or the result of the confounding effects of variation in environmental conditions, animal behaviour and s ling biases. Implications The stability of the dugong population between 2008 and 2012 is a positive outcome for local conservation and management of dugongs. This study also highlights the advisability of replicating baseline surveys to enable robust interpretation of temporal variation in population size estimates, and in turn, to improve the management of wildlife species.
Publisher: Springer Science and Business Media LLC
Date: 04-2002
Publisher: Frontiers Media SA
Date: 05-09-2018
Publisher: Inter-Research Science Center
Date: 20-11-2014
DOI: 10.3354/ESR00628
Publisher: Informa UK Limited
Date: 1999
Abstract: This project aimed to measure biochemical and cytogenetic biomarkers in marine fish (Aldrichetta forsteri and Sillago schomburgkii) associated with industrial and urban centres in South Australia. These sites were Port Pirie (affected by metal-contaminated outflows), Barker Inlet (adjacent to Metropolitan Adelaide), and Wills Creek (reference site). The biochemical biomarkers included sorbitol dehydrogenase (SDH) and alanine aminotransferase (ALAT) in serum, adenylate levels (ATP, ADP and AMP) and adenylate energy charge (AEC) in gill and liver, and sodium otassium ATPase (Na(+), K(+)-ATPase) in gill. Erythrocyte micronucleus frequency was a marker of cytogenetic effect. Serum enzyme levels were generally higher in fish from Port Pirie and Barker Inlet than in those from Wills Creek, with SDH demonstrating the clearest site-associated differences. Tissue adenylates were consistently lower at Port Pirie than elsewhere, suggesting a greater metabolic strain in fish at this site. AEC in gill and liver were consistently lower at Port Pirie than at Wills Creek, with Barker Inlet generally between these two. The reversed rank order was observed with erythrocyte micronucleus frequencies. Seasonal variations in the biomarkers may be attributed either to seasonal physiological changes in fish or changes in pollutant input levels or compositions. Na(+), K(+)-ATPase did not differ between sites nor seasons in this study. This work shows that biochemical and cytogenetic differences occur in marine fish at specific locations in South Australia. It also shows that of these tests, serum SDH and erythrocyte micronuclei are potentially the most sensitive and reliable biomarkers of pollutants effects on marine fish. The results also suggest that these data may be used as a baseline against which future changes in marine water quality, and their consequent biological effects, can be compared.
Publisher: Springer Science and Business Media LLC
Date: 05-01-2011
Publisher: Inter-Research Science Center
Date: 13-11-2009
DOI: 10.3354/ESR00224
Publisher: Inter-Research Science Center
Date: 17-10-2014
DOI: 10.3354/ESR00623
Publisher: CSIRO Publishing
Date: 17-05-2021
DOI: 10.1071/WR20183
Abstract: Context Hawksbill sea turtles (Eretmochelys imbricata) are conservation-dependent species in many areas of the world. A key component to ensuring successful conservation initiatives for the species is understanding their distribution and habitat use, in particular, knowing the nesting sites, migration routes and foraging areas for each genetic stock, and how these might overlap with threats. Aims Investigate the post-nesting movements of hawksbill sea turtles nesting in the Torres Strait, including migration movements and foraging ground size and distribution. Methods Nine nesting hawksbill turtles of the north-eastern Australian genetic stock were satellite-tagged between the 2010 and 2019 nesting seasons for 182 ± 143 days (mean ± s.d.). Key results Three turtles continued to nest on adjacent islands before commencing their post-nesting migrations. From the nine tracked turtles, the following three migration movement strategies were identified: (1) direct migration between the nesting beach and foraging ground, (2) non-direct movements with a period of meandering, and (3) establishment of two foraging areas separated by direct movement pathways. Foraging grounds were distributed across the Torres Strait and north-eastern Australia and varied in size between 0.54 km2 and 3.31 km2 (95% UD). None of the turtles migrated outside of Australian waters. Conclusions The localisation of these movements and habitats within Australian waters provides a unique conservation opportunity, whereby protection efforts involve multiple life stages and potentially preserve turtles from multiple genetic stocks. The variety of inter-nesting, migration and home range strategies used by the tracked turtles in the present study highlight the broad scope of hawksbill movements. Implications Our findings are useful for the implementation of future marine conservation areas and shed light into the nesting, migratory and foraging behaviours of hawkbills from this genetic stock. An understanding of the movement tracks and habitats used by a genetic pool is essential for well grounded implementation of conservation areas and management regulations.
Publisher: Wiley
Date: 27-04-2022
DOI: 10.1002/AQC.3813
Abstract: Increasing overlap between anthropogenic activities and wildlife can lead to problematic human–wildlife interactions. To manage these, an understanding of animal space‐use patterns, with sufficient temporal and spatial detail is required. Satellite telemetry can provide such detailed data however, the cost of tracking units places a significant limitation on s le size. Satellite tracks for 72 green turtles were consolidated through collaboration with multiple entities over 8 years at seven sites within a large industrial port contributing to an ecological monitoring initiative to minimize impacts of planned developments. This study aims to determine the minimum number of satellite‐tracked green turtles required to represent spatial distribution patterns in the foraging ground and to evaluate factors underpinning differences in distribution and site fidelity metrics to inform appropriate management strategies. An autocorrelated kernel density estimator was used to construct 95% utilization distributions for in idual turtles during each calendar season. Percentage overlap between pairs of seasonal utilization distributions was calculated as a measure of short‐term site fidelity. Mechanistic range shift analysis was applied to detect significant deviations from range residency behaviour. Green turtles exhibited spatially confined ranges and remained faithful to their foraging area for periods of up to 260 days. Range size was significantly different between microhabitats and study years. Only 16 in iduals (22% of tracked turtles) performed significant range shifts, indicating that occupied areas represent important habitats, and most turtles are unlikely to adjust their space‐use in response to anthropogenic or natural disturbances. Although this dataset represents an atypically large s le of satellite tracked in iduals, representative data were obtained at only two key sites. This study highlights the importance of evaluating clear objectives when s ling animals for satellite telemetry studies to obtain representation of sites, periods of interest, or age and sex cohorts.
Publisher: Elsevier BV
Date: 04-2011
Publisher: Elsevier BV
Date: 05-2001
DOI: 10.1016/S0025-326X(00)00168-5
Abstract: Port Pirie is the site of the largest lead smelter in the world, depositing 250 t of zinc, and 100 t of lead annually into Spencer Gulf. Barker Inlet is adjacent to metropolitan Adelaide, and receives unknown quantities of urban and industrial discharges. Both areas are sites of major commercial and recreational fisheries, contained within delicately balanced marine wetland ecosystems, comprising large areas of mangrove and seagrass habitats. Aldrichetta forsteri and Sillago schomburgkii are major species within these fisheries and as estuarine-dependent species were chosen for this study as indicator species for the detection and monitoring of pollutant impacts in the nearshore marine ecosystems of South Australia. Seston sediment collectors were deployed at each site and analysed seasonally for the presence of cadmium, lead and copper. Flesh s les from A. forsteri and S. schomburgkii were examined seasonally for the presence of cadmium, lead and copper and the results correlated with levels found in the seston sediment at each site. Metal concentrations were also correlated with a biomarker of genotoxicity measured in the same animals (micronuclei in erythrocytes) that were reported previously. Seston levels of cadmium, lead and copper were highest at Port Pirie, followed by Barker Inlet and were lowest at Wills Creek, with cadmium undetectable at the latter site. Metals in seston varied considerably with season, with generally higher levels in winter s les. In fish flesh, metal levels followed broadly similar trends as for seston. Spearman rank correlations between metals in seston and in flesh were strongly positive. There was also a significant correlation between flesh concentrations of each metal and the frequency of micronuclei in erythrocytes. This study has shown that seston concentration of pollutant metals are high in areas of industrial activity, and that these levels are also reflected in metal content of fish flesh. Mean flesh levels of cadmium and copper did not exceed Australian health based maximum permitted levels of fish for human consumption, whereas flesh levels of lead in fish from Port Pirie and Barker Inlet exceeded these standards in each of the seasons monitored. This may represent a significant dietary source of lead in humans, especially at Port Pirie where human lead exposure from terrestrial sources is important. There may also be the potential for accumulation of metals in residents of metropolitan Adelaide whose diets are high in fish (and/or crustaceans), particularly estuarine-dependent species, such as A. forsteri and S. schomburgkii. The study also showed that a non-specific biomarker of genotoxicity (micronuclei in erythrocytes) is potentially useful as a monitoring technique in fish species to evaluate their exposure and genotoxic responses to pollutants in South Australian waters. These data represent a snapshot of the current situation in this area and may act as background levels against which future improvements or decrements in water quality may be compared.
Publisher: Wiley
Date: 03-12-2009
DOI: 10.1002/AQC.1088
Publisher: Inter-Research Science Center
Date: 27-11-2013
DOI: 10.3354/ESR00462
Publisher: Chelonian Conservation and Biology Journal
Date: 06-2010
DOI: 10.2744/CCB-0803.1
Publisher: Public Library of Science (PLoS)
Date: 23-10-2020
Publisher: Springer Science and Business Media LLC
Date: 23-05-2022
DOI: 10.1007/S00227-022-04061-8
Abstract: Marine turtles encounter different threats during various life-history stages. Therefore, understanding their movements and spatial distribution is crucial for effectively managing these long-lived migratory organisms. This study combines satellite telemetry data with long-term capture-mark-recapture data derived from flipper tag studies to determine distribution patterns of endangered loggerhead turtles ( Caretta caretta ) during post-nesting migrations from different eastern Australian nesting sites. In iduals from the K’gari-Fraser Island and Great Barrier Reef island rookeries typically migrated northward, whereas in iduals from mainland rookeries migrated equally northward and southward. Despite this difference in foraging distribution, loggerheads from the different rookeries did not differ substantially in their migration duration or distance travelled. The foraging distribution identified from successful satellite tag deployments represented 50% of the foraging distribution identified from a large long-term flipper tag recovery database. However, these satellite telemetry results have identified new migration and foraging habitats not previously recognised for loggerhead turtles nesting in eastern Australia. Additionally, they support the conclusion from a past study using flipper tag recovery data that the mainland nesting turtles migrate to different foraging grounds than the turtles nesting on Great Barrier Reef islands. Collectively, the two data sources provide valuable data on the migration route, habitat distribution and ecological range for a threatened genetic stock of loggerhead turtles.
Publisher: Wiley
Date: 24-01-2020
DOI: 10.1002/AQC.3270
Publisher: CSIRO Publishing
Date: 2010
DOI: 10.1071/MF09142
Abstract: Sea turtles rely on reef islands for key parts of their reproductive cycle and require specific sediment characteristics to incubate their eggs and dig their nests. However, little is known about the sedimentological characteristics of sea turtle rookeries, how these sediment characteristics affect the vulnerability of rookeries to climate change, and the ecological implications of different sediment or altered sediment characteristics to sea turtles. Therefore, we described the sediment and identified the reef-building organisms of the seven most important rookeries used by the northern Great Barrier Reef (nGBR) green turtle population. We then reviewed the literature on the vulnerability of each identified reef-building organism to climate change and how various sediment characteristics ecologically affect sea turtles. Sediments from the studied rookeries are predominantly composed of well-sorted medium-grained to coarse-grained sands and are either dominated by Foraminifera, molluscs or both. Dissimilarities in the contemporary sedimentology of the rookeries suggest that each may respond differently to projected climate change. Potential ecological impacts from climate change include: (1) changes in nesting and hatchling emergence success and (2) reduction of optimal nesting habitat. Each of these factors will decrease the annual reproductive output of sea turtles and thus have significant conservation ramifications.
Publisher: Frontiers Media SA
Date: 09-01-2017
Publisher: Cambridge University Press (CUP)
Date: 22-07-2015
DOI: 10.1017/S0376892914000216
Abstract: Artificial lighting is a significant threat to bio ersity. Although efforts to reduce lighting are crucial for species’ conservation efforts, management is challenging because light at night is integral to modern society and light use is increasing with population and economic growth. The development and evaluation of appropriate light management strategies will require positive public support, and a comprehensive understanding of public engagement with light pollution. This is the first study to examine public engagement with reducing light at night for the protection of a threatened species. A community c aign to reduce artificial light use was initiated in 2008 to protect marine turtles at a globally significant nesting beach. Semi-structured questionnaires assessed community engagement with light-glow reduction, using an existing theoretical constraints framework. Despite high levels of cognitive and affective engagement (knowledge and concern), behavioural engagement (action) with light reduction in this community was limited. Community perceptions of light reduction were dominated by ‘uncertainty and scepticism’ and ‘externalizing responsibility/blame’, implying that behavioural engagement in this community may be increased by addressing these widely-held perceptions using modified c aign materials and/or strategic legislation. Further refinement of the theoretical constraints framework would better guide future empirical and conceptual research to improve understanding of public engagement with critical environmental issues.
Publisher: Inter-Research Science Center
Date: 21-06-2012
DOI: 10.3354/MEPS09747
Publisher: The Royal Society
Date: 05-2017
DOI: 10.1098/RSOS.170164
Abstract: The ability of in iduals to actively control their movements, especially during the early life stages, can significantly influence the distribution of their population. Most marine turtle species develop oceanic foraging habitats during different life stages. However, flatback turtles ( Natator depressus ) are endemic to Australia and are the only marine turtle species with an exclusive neritic development. To explain the lack of oceanic dispersal of this species, we predicted the dispersal of post-hatchlings in the Great Barrier Reef (GBR), Australia, using oceanographic advection-dispersal models. We included directional swimming in our models and calibrated them against the observed distribution of post-hatchling and adult turtles. We simulated the dispersal of green and loggerhead turtles since they also breed in the same region. Our study suggests that the neritic distribution of flatback post-hatchlings is favoured by the inshore distribution of nesting beaches, the local water circulation and directional swimming during their early dispersal. This combination of factors is important because, under the conditions tested, if flatback post-hatchlings were entirely passively transported, they would be advected into oceanic habitats after 40 days. Our results reinforce the importance of oceanography and directional swimming in the early life stages and their influence on the distribution of a marine turtle species.
Publisher: Elsevier BV
Date: 06-2017
Publisher: Elsevier BV
Date: 11-2018
Publisher: Elsevier BV
Date: 04-2016
Publisher: Wiley
Date: 11-06-2007
Publisher: Elsevier BV
Date: 08-2013
DOI: 10.1016/J.MARPOLBUL.2013.06.023
Abstract: Entanglement in derelict fishing gear and other marine debris is a major threat to the survival of large marine wildlife like cetaceans, seabirds and sea turtles. However, no previous reports of entanglement or entrapment have been recorded in sea snakes (Hydrophiinae). We report here on a sea snake (Hydrophis elegans) found with a ceramic washer encircling its body captured from the north-east coast of Queensland, Australia. The ring had constricted the body and over time caused extensive damage to the underlying tissues. A post-mortem examination showed the snake was severely emaciated as the ring restricted the passage of food to the stomach and intestine. This is the first record of mortality due to marine debris entrapment in sea snakes.
Publisher: Wiley
Date: 30-06-2019
DOI: 10.1002/AQC.3160
Publisher: Elsevier BV
Date: 04-2020
Publisher: Oxford University Press (OUP)
Date: 09-10-2015
Publisher: Elsevier BV
Date: 2010
Publisher: Elsevier BV
Date: 04-2019
Publisher: Elsevier BV
Date: 09-2004
Publisher: Inter-Research Science Center
Date: 22-01-2015
DOI: 10.3354/ESR00647
Publisher: Inter-Research Science Center
Date: 30-12-2016
DOI: 10.3354/ESR00801
Publisher: Elsevier BV
Date: 06-2016
DOI: 10.1016/J.MARPOLBUL.2016.03.040
Abstract: Environmental plastic pollution constitutes a significant hazard to marine turtles, human health and well-being. We describe a transdisciplinary approach to draw together findings from erse disciplines in order to highlight key environmental pollution problems and their consequences, together with social marketing-based strategies to address the problems. The ex le of plastic pollution and impacts to marine turtles illustrates the severity of the problem. Wildlife tourism and sustainable tourism activity have not focussed on specific behaviours to change and have had minimal impact on subsequent human behaviour regarding environmental issues, indicating the need for new strategies. Social marketing principles offer promise, but there is a need to investigate the utility of various theoretical foundations to aid the design and implementation of interventions. We offer insight towards using sophisticated multi-method research to develop insights into behaviours and segmentation-based strategies, that can aid the identification of barriers to, and enablers of, sustained behaviour change.
Publisher: Inter-Research Science Center
Date: 21-06-2012
DOI: 10.3354/MEPS09857
Publisher: Inter-Research Science Center
Date: 23-04-2013
DOI: 10.3354/ESR00482
Publisher: CSIRO Publishing
Date: 2016
DOI: 10.1071/MF15013
Abstract: Despite being critically endangered, the at-sea behaviour of hawksbill turtles (Eretmochelys imbricata) remains insufficiently understood to support a global conservation strategy. Habitat location and spatial use are poorly documented, which is particularly true for the globally important Australian hawksbill population. We equipped 10 adult female hawksbill turtles nesting on Groote Eylandt, northern Australia, with Fastloc GPS and Argos satellite transmitters. We quantified fine-scale habitat use and area-restricted search behaviour, and located potential feeding and developmental habitats by simulating hatchling turtle dispersal patterns by using a particle-tracking hydrological model. During the breeding season, females mostly remained near their nesting site. Post-breeding, all turtles migrated to foraging sites on the Australian continental shelf, primarily in the Gulf of Carpentaria in coastal seagrass pastures, but also offshore near coral-reef platforms. The distribution of adult foraging grounds was similar to simulated dispersal patterns of hatchling turtles from distant rookeries, thus highlighting the ecological significance of the Gulf of Carpentaria for hawksbill turtles. Although this hawksbill turtle population is likely to be endemic to Australian waters, national and international conservation initiatives are required to mitigate sources of anthropogenic mortality (e.g. illegal tortoise-shell trade, incidental captures in fishing gear, marine debris, seabed mining exploitation).
Publisher: Elsevier BV
Date: 2018
Publisher: Elsevier BV
Date: 02-2012
Publisher: Frontiers Media SA
Date: 21-02-2018
No related grants have been discovered for Mark Hamann.