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The dugong (Dugong dugon) is a marine mammal widely distributed throughout the Indo-Pacific and the Red Sea, with a Vulnerable conservation status, and little is known about many of the more peripheral populations, some of which are thought to be close to extinction. We present a de novo high-quality genome assembly for the dugong from an individual belonging to the well-monitored Moreton Bay population in Queensland, Australia. Our assembly uses long-read PacBio HiFi sequencing and Omni-C data following the Vertebrate Genome Project pipeline to reach chromosome-level contiguity (24 chromosome-level scaffolds; 3.16 Gbp) and high completeness (97.9% complete BUSCOs). We observed relatively high genome-wide heterozygosity, which likely reflects historical population abundance before the last interglacial period, approximately 125,000 yr ago. Demographic inference suggests that dugong populations began declining as sea levels fell after the last interglacial period, likely a result of population fragmentation and habitat loss due to the exposure of seagrass meadows. We find no evidence for ongoing recent inbreeding in this individual. However, runs of homozygosity indicate some past inbreeding. Our draft genome assembly will enable range-wide assessments of genetic diversity and adaptation, facilitate effective management of dugong populations, and allow comparative genomics analyses including with other sirenians, the oldest marine mammal lineage. [ABSTRACT FROM AUTHOR]

Estuarine and coastal waters are areas of potential concern for antimicrobial resistance because of the discharge of wastewater from sewage treatment plants and the run-off from urban and agricultural lands. Herein, we evaluate the antimicrobial resistance profiles in bacteria from dugongs (Dugong dugon), mammals that inhabit and feed in shallow coastal regions and, thus, are vulnerable to encountering water and sediment contaminated by human activities. Bacterial isolates were cultured from fresh faeces of four wild dugongs, as well as from one sediment sample from a dugong foraging ground in Queensland, Australia. Ten bacterial isolates underwent phenotypic antimicrobial susceptibility testing using disc diffusion and minimum inhibitory concentration testing, and genotypic resistance and virulence gene identification through whole genome sequencing. Four Staphylococcus warneri isolates and one Bacillus cereus isolate from dugong faeces were resistant to penicillin, with two S. warneri isolates also displaying resistance to trimethoprim. Four Escherichia coli isolates were all resistant to ampicillin. Resistance genes, including fosB, BcII, dfrC, blaZ, and mdfA, were identified in the isolates cultured from dugong faeces with two virulence genes (gad and lpfA) identified in all E. coli isolates. Lysinibacillus sphaericus cultured from the marine sediment and B. cereus from dugong faeces displayed phenotypic multidrug resistance (across categories of nonextended spectrum cephalosporins, penicillins and beta-lactamase inhibitors, and clindamycin; and for L. sphaericus, phosphonic acids). These results demonstrate the role that dugongs can play as a sentinel species for antimicrobial resistance in the coastal waters across their range, which includes both disturbed urban and rural regions. [ABSTRACT FROM AUTHOR]

Despite the lack of obvious physical barriers and their ability to travel significant distances, many marine mammals exhibit substantial population structuring over relatively short geographical distances. The dugong (Dugong dugon), the only extant representative of family Dugongidae, is listed as Vulnerable to Extinction globally. We investigated the genetic population structure of dugongs in the shallow coastal waters along >2,000 km of the eastern Queensland coast, including the Great Barrier Reef region. Microsatellite genotypes for 22 loci in 293 dugongs, SNP genotypes based on 10,690 loci in 43 dugongs, and 410 bp mitochondrial control‐region sequences from 639 dugongs were analyzed. Clustering analysis techniques consistently identified an abrupt genetic break in the Whitsunday Islands region (20.3°S), which interrupts an overall pattern of isolation‐by‐distance. Geographic distance was relatively more important than sea‐surface temperature and seagrass distribution in explaining pairwise microsatellite genetic distances. The cause of reduced dispersal across this region is unknown but might relate to an unusual tidal and current mix, termed the "sticky‐water" effect, and/or a break in the geographical distribution of off‐shore seagrass meadows. The genetic structure suggests distinct breeding units north and south of the Whitsunday Islands region for consideration in further developing management plans for Queensland dugongs. [ABSTRACT FROM AUTHOR]

The dugong (Dugong dugon) is an herbivorous marine mammal that inhabits tropical inshore waters and thus may be vulnerable to pollutants and terrestrial pathogens as a result of coastal runoff. In this study, serum samples collected from live, wild dugongs (n = 114) in an embayment located on the urbanized southeast Queensland coast of Australia during 2008–2014, were measured for IgG antibody levels specific to Toxoplasma gondii and Neospora caninum. An ELISA used to measure T. gondii tachyzoite antibodies indicated a non‐Gaussian distribution of antibody level, with five dugongs identified as high outliers. Mean levels of antibodies specific for T. gondii in dugongs sampled in 2014 were significantly higher than in 2010 (p =.006) and 2011 (p =.009) with an elevation in mean antibody levels after a major 2011 flood event relative to antibody levels prior to the flood (p <.0001). A competitive ELISA to detect N. caninum antibody indicated a normal distribution of antibody with no high outliers. Mean antibody level for N. caninum was highest in 2012 and declined significantly in 2014 (p =.004). This is the first survey of antibodies directed against T. gondii and N. caninum in dugongs and suggests future health monitoring of this species. [ABSTRACT FROM AUTHOR]

Knowledge of the relationships between environmental forcing and demographic parameters is important for predicting responses from climatic changes and to manage populations effectively. We explore the relationships between the proportion of sea cows (Dugong dugon) classified as calves and four climatic drivers (rainfall anomaly, ], NINO 3.4 sea surface temperature index, and number of tropical cyclones) at a range of spatially distinct locations in Queensland, Australia, a region with relatively high dugong density. Dugong and calf data were obtained from standardized aerial surveys conducted along the study region. A range of lagged versions of each of the focal climatic drivers (1 to 4 years) were included in a global model containing the proportion of calves in each population crossed with each of the lagged versions of the climatic drivers to explore relationships. The relative influence of each predictor was estimated via Gibbs variable selection. The relationships between the proportion of dependent calves and the climatic drivers varied spatially and temporally, with climatic drivers influencing calf counts at sub-regional scales. Thus we recommend that the assessment of and management response to indirect climatic threats on dugongs should also occur at sub-regional scales. [ABSTRACT FROM AUTHOR]

Understanding the patterns of movement and breeding within and between wildlife populations is important for the assessment of conservation status of endangered species, the development of conservation management strategies and priorities, and the prediction of population behaviour based on future threats. Methods for determining long term gene flow and dispersal are well researched, but analysis of recent movement is more difficult, typically relying on real-time tracking of individuals using telemetry, or through identification of marked individuals at multiple locations. These methods are limited by the considerable sampling effort required over time periods sufficient to recapture individuals in multiple locations. In contrast, we can infer recent movement from a reconstructed pedigree based on genetic and ancillary biological data, by identifying parent-offspring relationships in which the parent and offspring may be found in different locations. Hence, this method can use a single sampling period to identify movement and possibly associated breeding events over the last one or two generations. This study demonstrates the utility of reconstructed pedigrees in inferring recent movements in a dugongs distributed across a number of spatially distinct foraging locations in southern Queensland, Australia. Dugongs, which are classified as vulnerable to extinction, have long lifespans and protracted breeding cycles and give birth to single offspring at irregular intervals, implying a complex pedigree without distinct generational structure or large sibling groups. A pedigree was constructed for 1002 different dugongs across four locations in southern Queensland: Moreton Bay ( n = 630), the Great Sandy Straits ( n = 281), Hervey Bay ( n = 59) and Shoalwater Bay ( n = 27) using PR-genie software. PR-genie is a pedigree reconstruction system designed specifically for complex multigenerational wildlife pedigrees based on genetic identity (microsatellite DNA) and including ancillary biological data (sex and body size-class). Movements of genetically tagged individuals between locations were detected as parent-offspring links found across locations. Approximately 30% of assigned parents had at least one offspring found in a different location, implying recent movement of the parent or offspring. Where multiple individuals in a family are present, parsimonious explanations of movement indicate that male dugongs move between populations more frequently than females. Markedly more movement between locations was found than has been previously possible to detect through repeated direct sampling of individuals or through telemetry. [ABSTRACT FROM AUTHOR]

Populations of marine mammals can show the signature of phylogeographical breaks and restricted connectivity despite the apparent lack of physical boundaries in the marine environment and their high dispersal abilities. Dugongs ( Dugong dugon) do not appear to undertake regular migrations but may show localised movement related to water temperature or seagrass availability. Previous mitochondrial DNA studies suggested that despite a strong phylogeographic break in the Torres Strait, there is local panmixia in Australian waters. In this study, we conducted a comprehensive study of the four major dugong populations in southern Queensland. We analysed genotypes of 1,293 dugongs based on 24 microsatellite loci from the four major dugong locations in the region (from south to north): Moreton Bay, Great Sandy Straits, Hervey Bay and Shoalwater Bay. Diversity levels were similar across locations (observed heterozygosity 0.48-0.52, allelic richness 4.3-4.5). There was low but significant population differentiation in southern Queensland (F ranged from 0.005 to 0.040 and Jost's D ranged from 0.001 to 0.031 for microsatellite data). Bayesian clustering analysis implemented in STRUCTURE largely distinguished the southern Moreton Bay population from the three more northern populations. Twelve mitochondrial control region haplotypes identified from a subset of 182 samples confirmed significant population structuring (F ranged from 0.16 to 0.28). These data suggested that the frequency and extent of dugong movements are insufficient to disrupt the long-term existence of at least two breeding populations in southern Queensland. [ABSTRACT FROM AUTHOR]

Through the effects of colonisation, materials such as food, tools and medicines are appropriated and transformed to appeal to different consumer groups creating new points of interaction and combined histories. These products flow through colonial pathways between indigenous peoples and Europeans and create a connection in which interactions are inevitable. In Australia, dugong oil was a product that traversed the spatial and racial divide being consumed by both Aboriginal and white people. I argue that whether used as a 'scientific' medicine bought at the local chemist, a detested medicine enforced by colonial authorities, or a remedy passed down through generations, the story of dugong oil uncovers the duality of objects and complicates the history of Aboriginal-European interaction. [ABSTRACT FROM AUTHOR]

Abstract: Halogenated natural products (HNPs) are frequently detected in marine organisms. High HNP concentrations have previously been found in marine mammals from the Great Barrier Reef, Australia, including in the blubber of herbivorous dugongs (Dugong dugon). To identify the source of HNPs we initially focused on the analysis of Australian seagrass (Halophila ovalis) which serves as the principal food source for dugongs. GC/MS analysis of the seagrass indicated the presence of several organobromine compounds. One compound was identified as 2,3,4,5-tetrabromo-1-methylpyrrole (TBMP) by synthesis. Subsequent analysis of semipermeable membrane devices demonstrated that the photo-sensitive TBMP is widespread in the Great Barrier Reef (Queensland, Australia). The detection of larger TBMP concentrations in fish fillets from Chile and traces in mussels from New Zealand indicated that this potential HNP may be distributed throughout the Southern Pacific Ocean. [Copyright &y& Elsevier]

The challenge of developing environmental outcomes acceptable to stakeholders with different values is well documented. Discourse analysis provides insights into how the views of different stakeholders affect decision making. We studied the discourses of key actors associated with the implementation of a Turtle and Dugong Hunting Management Plan developed by Hope Vale Aboriginal community in the Great Barrier Reef World Heritage Area, Australia. The discourses of the environmental managers and community members were very different. Hope Vale people prioritized cultural well-being; the staff of management agencies prioritized biodiversity outcomes. These differences precluded effective outcomes despite considerable investment in hunting management over more than 20 years by both groups. Understanding the discursive terrain within environmental management domains can inform environmental decision making and the implementation of agreed management arrangements, enabling biodiversity objectives and Indigenous cultural aspirations to be met in a socially just, economically viable, and environmentally sustainable way. [ABSTRACT FROM AUTHOR]

The dugong (Dugong dugon) is a vulnerable marine mammal with large populations living in urban Queensland waters. A mark-recapture program for wild dugongs has been ongoing in southern Queensland since 2001. This program has involved capture and in-water sampling of more than 700 dugongs where animals have been held at the water surface for 5 min to be gene-tagged, measured, and biopsied. In 2008, this program expanded to examine more comprehensively body condition, reproductive status, and the health of wild dugongs in Moreton Bay. Using Sea World's research vessel, captured dugongs were lifted onto a boat and sampled out-of-water to obtain accurate body weights and morphometrics, collect blood and urine samples for baseline health parameters and hormone profiles, and ultrasound females for pregnancy status. In all, 30 dugongs, including two pregnant females, were sampled over 10 d and restrained on deck for up to 55 min each while biological data were collected. Each of the dugongs had their basic temperature-heart rate-respiration (THR) monitored throughout their period of handling, following protocols developed for the West Indian manatee (Trichechus manatus). This paper reports on the physiological response of captured dugongs during this out-of-water operation as indicated by their vital signs and the suitability of the manatee monitoring protocols to this related sirenian species. A recommendation is made that the range of vital signs of these wild dugongs be used as benchmark criteria of normal parameters for other studies that intend to sample dugongs out-of-water. [ABSTRACT FROM AUTHOR]

Quantifying the factors influencing behaviors of aquatic mammalian grazers may enhance the generic understanding of grazer ecology. We investigated diel and tidal patterns in movements of the dugong (Dugong dugon) by Global Positioning System--tracking 12 animals in 5 inshore--intertidal and 3 offshore--subtidal habitats along the coast of Queensland, Australia. We examined effects of tide height and time of day on the dugong's distance from 1) the nearest coast, 2) water >3 m deep, 3) actual water depth (bathymetry + tide ht) experienced, and 4) distribution of the directions of movements. Both tidal and diel cycles influenced dugong movement. Tracked dugongs tended to be closer to shore at high tide than at low tide and closer to shore at night than during the day. Onshore movement was more prevalent on incoming tides and in the afternoon and evening. Offshore movement was more prevalent on outgoing tides and from midnight through the morning until midday. Tidal and diel variation in water depths used by the inshore--intertidal dugongs was small, but probably underestimated, hidden by a sampling bias in the telemetry equipment. Onshore movement at high tide allowed dugongs to exploit intertidal seagrass beds. Dugongs are closer to shore in afternoons and evenings than in mornings. This behavior may be related to the avoidance of predators or watercraft. Our findings can be used to predict spatial patterns of dugongs within areas of conservation management significance and to assess, avoid, and mitigate adverse effects of anthropogenic disturbance. [ABSTRACT FROM AUTHOR]

The historical exploitation of marine resources in Queensland has only been partially documented. In particular, the history of the commercial fishing of dugongs and marine turtles has received comparatively little scholarly attention. Since European settlement in Queensland, various human activities have exploited these resources. We present documentary and oral history evidence of the scale of those industries. Based on extensive archival and oral history research, we argue that diverse fishing practices occurred and that the sustained exploitation of dugongs, green turtles, and hawksbill turtles led to observable declines in the numbers of these animals – now species of conservation concern. [ABSTRACT FROM AUTHOR]

Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in numerous products. These compounds have been found to enter the marine environment where they have the potential to bioaccumulate in biota. Limited information is currently available concerning the levels of PBDEs in Australian marine wildlife. This study presents baseline information on PBDE levels in a variety of marine species from Queensland, Australia and considers the influence of species-specific factors on contaminant levels and tissue distribution in marine turtles. Overall, the PBDE levels measured in this study are relatively low compared to marine biota from the northern hemisphere, indicating low level input into the marine system of Queensland. This is in general agreement with global estimates which suggest low PBDE usage in Australia. Previous studies, however, have found relatively high PBDE levels in Australian human milk and sera. This discrepancy in contamination trends between terrestrial and marine biota suggests that future transport of PBDEs may occur to the marine system in Australia. [Copyright &y& Elsevier]

Abstract: Okadaic acid (OA) is a diarrhetic shellfish poison (DSP) produced by a number of marine organisms including the benthic dinoflagellate Prorocentrum lima, which are often found on seagrass. As seagrass forms the basis of the diet of dugong (Dugong dugon) and green turtle (Chelonia mydas), these herbivores may potentially be exposed to OA through ingestion of P. lima found on the seagrass. In this study, the abundance of epiphytic P. lima, on seagrass, and the concentration of OA produced by these epiphytic dinoflagellates was measured in Moreton Bay, Queensland, Australia. P. lima and OA were found on all four species of seagrass collected. OA was detected in epiphytic material collected from seagrass, with a maximum of 460ngOA/kg(wwtSG) found on Halophila spinulosa. From this information, the estimated maximum daily intake (DI) of OA by an adult dugong consuming 40kg(wwtSG)/day was 18,400ng/day, and an adult turtle consuming 2kg(wwtSG)/day was 920ng/day. Analysis by HPLC/MS/MS of 54 stranded dugongs and 19 stranded turtles did not yield OA above the detection limit of 10,000ng/kg(animal tissue). OA was found on seagrass, however it was not detected in the tissue samples of dugongs and turtles. [Copyright &y& Elsevier]

Ecosystem-scale networks of marine protected areas (MPAs) are important conservation tools, but their effectiveness is difficult to quantify in a time frame appropriate to species conservation because of uncertainties in the data available. The dugong (Dugong dugon ) is a mobile marine species that occurs in shallow inshore waters of an ecosystem-scale network of MPAs (the Great Barrier Reef World Heritage Area [GBRWHA]). We developed a rapid approach to assess risk to dugongs in the region and evaluate options to ameliorate that risk. We used expert opinion and a Delphi technique to identify and rank 5 human factors with the potential to adversely affect dugongs and their sea grass habitats: netting, indigenous hunting, trawling, vessel traffic, and poor-quality terrestrial runoff. We then quantified and compared the distribution of these factors with a spatially explicit model of dugong distribution. We estimated that approximately 96% of habitat of high conservation value for dugongs in the GBRWHA is at low risk from human activities. Using a sensitivity analysis, we found that to decrease risk, commercial netting or indigenous hunting had to be reduced in remote areas and the effects of vessel traffic, terrestrial runoff, and commercial netting had to be reduced in urban areas. This approach enabled us to compare and rank risks so as to identify the most severe risks and locate specific sites that require further management attention. [ABSTRACT FROM AUTHOR]

Indigenous people of the Torres Strait Islands have been concerned about the safety of their traditional seafoods since the discovery of high cadmium levels in the liver and kidney of dugong and turtle in 1996. This study explored links between urinary cadmium levels and consumption frequency of these traditional foods and piloted a community-based methodology to identify potential determinants of cadmium exposure and accumulation. Consultations led to selection of one community for study from which 60 women aged 30 to 50 years participated in health and food frequency survey, urine collection and a routine health check. Urinary cadmium levels were determined by inductively coupled plasma-mass spectrometry; data were analysed using SPSS-14. The geometric mean cadmium level in this group of women was 1.17 (arithmetic mean 1.86) μg/g creatinine with one-third exceeding 2.0 μg/g creatinine. Heavy smoking (≥300 pack years) was linked to higher cadmium in urine, as was increasing age and waist circumference. Analysis of age-adjusted residuals revealed significant associations (P<0.05) between cadmium level and higher consumption of turtle liver and kidney, locally gathered clams, peanuts, coconut, chocolate and potato chips. Dugong kidney consumption approached significance (P=0.06). Multiple regression revealed that 40% (adjusted r2) of variation in cadmium level was explained by the sum of these associated foods plus heavy smoking, age and waist circumference. No relationships between cadmium and pregnancy history were found. This paper presents a novel approach to explore contributions of foods and other factors to exposure to toxins at community level and the first direct evidence that frequent turtle (and possibly dugong) liver and kidney and wild clam consumption is linked to higher urinary cadmium levels among Torres Strait Islander women.Journal of Exposure Science and Environmental Epidemiology (2007) 17, 298–306. doi:10.1038/sj.jes.7500547; published online 24 January 2007 [ABSTRACT FROM AUTHOR]

This article informs that Great Barrier Reef World Heritage Area and the adjacent coast of southeast Queensland are some of the best-protected marine ecosystems in the world. The Great Barrier Reef Region is the world's largest marine protected area. It is located off a coast with a relatively low human population density and most major anthropogenic impacts are relatively recent. Large multiple-use marine parks have also been established in the two large bays on the Queensland coast south of the Great Barrier Reef Region, Moreton Bay and Hervey Bay. These regions are far from pristine, and knowledge of the historical abundance of key species is important if targets are to be developed for conservation management. In Australian waters, the range of the dugong extends across the northern coast from Shark Bay in Western Australia to Moreton Bay in southern Queensland. Genetic studies using MtDNA reveal two maternal lineages, which apparently reflect the effects of sea-level changes over geological time. One lineage is restricted to the coast of Queensland and part of the Northern Territory while the other occurs across the entire Australian range.

A range of organohalogen compounds (10 polychlorinated biphenyl [PCB] congeners, DDT and metabolites, chlordane-related compounds, the potential natural organochlorine compound Q1, toxaphene, hexachlorobenzene, hexachlorocyclohexanes, dieldrin, and several yet unidentified brominated compounds) were detected in the blubber of four bottlenose dolphins (Tursiops truncatus), one common dolphin (Delphinus delphis), and seven dugongs (Dugong dugon), as well as in adipose tissue of a green turtle (Chelonia mydas) and a python (Morelia spilota) from northeast Queensland (Australia). The green turtle and dugongs accumulated lower organohalogen levels than the dolphins. Lower levels in dugongs were expected because this species is exclusively herbivorous. Highest PCB and DDT levels recorded in dugongs were 209 and 173 μg/kg lipids, respectively. Levels of the nonanthropogenic heptachlorinated compound Q1 (highest level in dugongs was 160 μg/kg lipids) were estimated using the ECD response factor of trans-nonachlor. Highest organohalogen levels were found in blubber of dolphins for sumDDT (575–52,500 μg/kg) and PCBs (600–25,500 μg/kg lipids). Furthermore, Q1 was a major organohalogen detected in all samples analyzed, ranging from 450–9,100 μg/kg lipids. The highest concentration of Q1 determined in this study represents the highest concentration reported to date in an environmental sample. Levels of chlordane-related compounds were also high (280–7,700 μg/kg, mainly derived from trans-nonachlor), but concentrations of hexachlorobenzene, hexachlorocyclohexanes, dieldrin, and toxaphene were relatively low and contributed little to the overall organohalogen contamination. Furthermore, a series of three major (BC-1, BC-2, and BC-3) and six minor (BC-4 through BC-9) unknown brominated compounds were observable by extracting m/z 79 and m/z 81 from the GC/ECNI-MS full scan run. Structural proposals were made for the two major recalcitrant compounds (referred to as BC-1 and BC-2). BC-2 appears to be a tetrabromo-methoxy-diphenylether (512 u) and BC-1 has 14 u (corresponding with an additional CH2 group) more relative to BC-1. In general, the organohalogen pattern observed in blubber of dolphins was different compared to similar samples from other locations in the world, which is apparent from the fact that the four major abundant signals in the GC/ECD chromatogram of D. delphis originated from the four unknown compounds Q1, BC-1, BC-2, and BC-3. [ABSTRACT FROM AUTHOR]

n adult female dugong ( Dugong dugon) was found dead and floating in Moreton Bay, Queensland, Australia. This animal was found to have a 360° mesenteric volvulus with infarction of the associated segment of small intestine, and fibrinous peritonitis. Mortality was attributed to the volvulus and its sequelae. The cause was not apparent on gross or histological examination. [ABSTRACT FROM AUTHOR]

Dugongs (Dugong dugon) are an iconic and strictly herbivorous species. They inhabit coastal areas, which brings them in contact with urban and agricultural pollutant sources, yet their exposure and susceptibility to environmental pollutants is still largely unknown. The goal of this study was to investigate the presence of several legacy compounds such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and pesticides as well as naturally produced MeO-PBDEs in male and female dugongs from Moreton Bay (n = 24), a semi-enclosed embayment close to Australia's third largest city, Brisbane. Results show that concentrations of all investigated compounds are low in general (<120 ng/g lipid weight) and below known toxicity thresholds established for marine mammals. However, concentrations found in this study are higher or comparable to concentrations in dugongs outside Moreton Bay or in sirenians worldwide. No temporal trends for POPs from 2001 until 2012 were found for adult animals suggesting that environmental changes are only slowly reflected in dugongs. Finally, pollutant profiles in dugongs are limited to the most persistent PCBs, pesticides and PBDEs that also dominate POP profiles in other marine mammal species in general., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Presents updates on the harmful changes occurring in the Great Barrier Reef in Australia, according to the "2003 State of the Reef" report. Sources of increased sediment and nutrient flows that are smothering inner reefs and promoting algal growth; Decline in the population of nesting loggerhead turtle and dugongs living in the area; Efforts of the Australian government to protect the reef.

Cold stress syndrome (CSS) is the term used to describe the range of clinical signs and chronic disease processes that can occur in Florida, USA, manatees Trichechus manatus latirostris exposed to water temperatures below 20°C for extended periods. Although no cold-related adverse events have been described in the closely related dugong Dugong dugon thus far, it has been established that they make movements in response to water temperatures lower than about 17 to 18°C. In this study, archive reports for dugong carcasses submitted to The University of Queensland School of Veterinary Science for post mortem examination during 2010 to 2012 were examined. These animals had been recovered from Moreton Bay, southeast Queensland, Australia, and 10 out of 14 fulfilled the criteria for 'potential cold stress cases.' Epidermal hyperplasia and secondary bacterial infection, serous atrophy of pericardial adipose tissue, and multisystem abscessation were features commonly noted in these cases. Water temperature data were correlated with the time of year that carcasses were submitted for examination. Higher numbers of carcasses diagnosed with potential CSS were noted during sustained periods in which water temperature was below 20°C. Given the pattern of increased submission of non-specifically, chronically unwell animals in the colder months and evidence that environmental conditions known to precipitate CSS occur in southeast Queensland, it is probable that, like manatees, dugongs in this area are affected by CSS. Further investigation to confirm and to better characterize the syndrome is recommended to refine management practices and improve treatment of affected animals.

Microbial infection may contribute to disease in a significant proportion of marine mammal mortalities, but little is known about infectious bacterial species and their prevalence in dugongs (Dugong dugon). This study represents a survey of the species of bacteria and fungi isolated from dugongs submitted to the University of Queensland's School of Veterinary Science for postmortem examination. Thirty-six dugongs were included in the survey, with 23 species of bacteria and four species of fungus cultured from lesions that were suspected of contributing to local infection, systemic infection, or both. The most abundant bacteria included Aeromonas spp., Clostridium spp., Vibrio spp., Enterococcus faecalis, and Pseudomonas spp. In six cases, the microorganism(s) cultured were considered to have been associated with disease. Mixed infections containing Aeromonas spp. and Vibrio spp.; Morganella morganii, Pasteurella multocida, and Serratia marcescens; and Actinomyces spp. and Peptostreptococcus spp. were associated with pneumonia or pleuritis, and Enterococcus faecalis was associated with a multisystemic infection in a neonate. Clostridium spp. was cultured from two animals with peritonitis and likely septicemia. The significance of many of the other isolates is uncertain because the samples were taken after death, and some of the species isolated may represent postmortem overgrowth. It is also difficult to fulfil Koch's postulates through experimental infection in marine mammals. Regardless, this information will assist clinicians working with dugongs to make treatment decisions and the baseline data on the prevalence of bacterial and fungal species is of value for monitoring coastal water habitat health and risks of zoonotic disease transmission.

To better record and characterize mortality in the declining population of dugong (Dugong dugon) in southeast Queensland, Australia, animals were collected and brought to the University of Queensland for postmortem examination. Fifty-five animals were examined over a 14-yr period. Human activities commonly caused the animal death. Several deaths were attributed to primary or secondary infections and idiopathic and degenerative diseases. A significant proportion of animals were found to have nonspecific signs of chronic debility, but the causes of disease and mortality in these cases remains to be identified.

The Great Barrier Reef (GBR) provides a globally significant demonstration of the effectiveness of large-scale networks of marine reserves in contributing to integrated, adaptive management. Comprehensive review of available evidence shows major, rapid benefits of no-take areas for targeted fish and sharks, in both reef and nonreef habitats, with potential benefits for fisheries as well as biodiversity conservation. Large, mobile species like sharks benefit less than smaller, site-attached fish. Critically, reserves also appear to benefit overall ecosystem health and resilience: outbreaks of coral-eating, crown-of-thorns starfish appear less frequent on no-take reefs, which consequently have higher abundance of coral, the very foundation of reef ecosystems. Effective marine reserves require regular review of compliance: fish abundances in no-entry zones suggest that even no-take zones may be significantly depleted due to poaching. Spatial analyses comparing zoning with seabed biodiversity or dugong distributions illustrate significant benefits from application of best-practice conservation principles in data-poor situations. Increases in the marine reserve network in 2004 affected fishers, but preliminary economic analysis suggests considerable net benefits, in terms of protecting environmental and tourism values. Relative to the revenue generated by reef tourism, current expenditure on protection is minor. Recent implementation of an Outlook Report provides regular, formal review of environmental condition and management and links to policy responses, key aspects of adaptive management. Given the major threat posed by climate change, the expanded network of marine reserves provides a critical and cost-effective contribution to enhancing the resilience of the Great Barrier Reef.

Tissue samples of liver and blubber were salvaged from fifty-three dugong (Dugong dugon) carcasses stranded along the Queensland coast between 1996 and 2000. Liver tissue was analysed for a range of heavy metals and blubber samples were analysed for organochlorine compounds. Metal concentrations were similar in male and female animals and were generally highest in mature animals. Liver concentrations of arsenic, chromium, iron, lead, manganese, mercury and nickel in a number of individual animals were elevated in comparison to concentrations previously reported in Australian dugong. Dieldrin, DDT (and its breakdown products) and/or heptachlor epoxide were detected in 59% of dugong blubber samples. In general, concentrations of organochlorines were similar to those reported in dugong 20 years earlier, and were low in comparison to concentrations recorded from marine mammal tissue collected elsewhere in the world. With the exception of lead, the extent of carcass decomposition, the presence of disease or evidence of animal starvation prior to death did not significantly affect dugong tissue concentrations of metals or organochlorines. The results of the study suggest that bioaccumulation of metals and organochlorine compounds (other than dioxins) does not represent a significant risk to Great Barrier Reef dugong populations, particularly in the context of other pressures associated with coastal development and other anthropogenic activities.