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Context Assessing the distribution and abundance of marine fauna and the ecological status of coastal and pelagic ecosystems is key to biodiversity conservation, but the monitoring of mobile marine species raises multiple logistical and financial challenges.Aims The project describes the distribution, abundance and taxonomic assemblage of several marine megafauna taxa in three subregions of the western and central South Pacific Ocean (New Caledonia, Wallis and Futuna, and French Polynesia).Methods Large-scale aerial surveys were conducted using a standardised multi-taxon protocol, to characterise the occurrence and abundance of marine megafauna over 2.5 million km2. Analysing more than 122 000 km of transects, the densities of 22 different taxa were estimated: seven taxonomic groups of marine mammals (Physeteridae, Kogiidae, Ziphiidae, Globicephalinae, Small Delphininae, Large Delphininae, and Dugongidae), a single group for hard-shelled sea turtles, three groups of elasmobranchs (including whale sharks), and 11 groups of seabirds (including Phaethontidae, Hydrobatidae, Fregatidae and Sulidae).Key results Contrasting patterns of species distribution were found. Marine mammal diversity increases north and west, with a distinct species assemblage in New Caledonia, compared to other subregions. A strong latitudinal gradient was observed across French Polynesia, independent of taxa.Conclusions This study provides the first comparison of marine species assemblages across the three oceanic subregions and sets a regional baseline for the biogeography of marine megafauna in the region.Implications The taxonomic and spatial extension of the results opens up new perspectives for the development of local conservation measures, especially for taxa with already documented population declines. This study simultaneously describes the spatial distribution and densities of 22 distinct taxonomic groups of marine mammals, sea turtles, elasmobranchs and seabirds over three large oceani

Context The dynamic habitat use by dugongs (Dugong dugon) in small coral reef lagoon systems spatially limited by tides is not well understood and has hampered adaptive management. Aims We investigated how dugongs locally used a high conservation value coral-reef lagoon system during different seasons and tides to support local management. Methods We conducted local-scale aerial surveys to document the seasonal and tidal changes in the distribution and number of dugongs over seagrass and non-seagrass coral reef habitats in a small lagoon in New Caledonia. The surveys were conducted fortnightly over 18 months in different seasons and at different tides. Temperature loggers and existing local footage of dugong herding behaviour were used to study the habitat use and behaviour of the animals in the area. Key results More dugongs were sighted in Cap Goulvain during the cool season than during the warm season. As tides restricted access to the intertidal seagrass meadows and during the cool season, more dugongs were sighted outside the lagoon on the fore reef shelf outside the lagoon. Dugongs were resting in large aggregations during their use of this non-seagrass habitat. Conclusions Our study emphasises the importance of non-seagrass habitats for dugongs in spatially restricted coral reef environments as well as the importance of considering outer lagoon habitats as key dugong management areas. This study also adds evidence of behavioural thermoregulation in dugongs. Implications The development of dynamic management strategies is essential, especially where different habitats should be protected at different times of the year.

There are many advantages to transitioning from conducting marine wildlife surveys via human observers onboard light-aircraft, to capturing aerial imagery using drones. However, it is important to maintain the validity of long-term data series whilst transitioning from observer to imagery surveys. We need to understand how the detection rates of target species in images compare to those collected from observers in piloted aircraft, and the factors influencing detection rates from each platform. We conducted trial ScanEagle drone surveys of dugongs in Shark Bay, Western Australia, covering the full extent of the drone’s range (∼100 km), concurrently with observer surveys, with the drone flying above or just behind the piloted aircraft. We aimed to test the assumption that drone imagery could provide comparable detection rates of dugongs to human observers when influenced by same environmental conditions. Overall, the dugong sighting rate (i.e., count of individual dugongs) was 1.3 (95% CI [0.98–1.84]) times higher from the drone images than from the observers. The group sighting rate was similar for the two platforms, however the group sizes detected within the drone images were significantly larger than those recorded by the observers, which explained the overall difference in sighting rates. Cloud cover appeared to be the only covariate affecting the two platforms differently; the incidence of cloud cover resulted in smaller group sizes being detected by both platforms, but the observer group sizes dropped much more dramatically (by 71% (95% CI [31–88]) compared to no cloud) than the group sizes detected in the drone images (14% (95% CI [−28–57])). Water visibility and the Beaufort sea state also affected dugong counts and group sizes, but in the same way for both platforms. This is the first direct simultaneous comparison between sightings from observers in piloted aircraft and a drone and demonstrates the potential for drone surveys over a large spatial-scale.

We conducted trial ScanEagle drone surveys of dugongs in Shark Bay, Western Australia, covering the full extent of the drone’s range (~ 100 km), concurrently with observer surveys, with drone flying above or just behind the piloted aircraft. We aimed to test the assumption that drone imagery could provide comparable detection rates of dugongs to human observers when influenced by same environmental conditions. Data in "All data for analysis - Shark Bay Hodgson et al" include a summary of the sightings from both platforms per transect segment, including associated environmental covariates. Also included are details of each dugong group sighted by each platform. "Comparison between reviewers - Shark Bay Hodgson et al" contains details of the drone image sightings recorded for a subset of drone images that were reviewed by three reviewers. These data were used to compare the reviewers and calculate perception bias for the manual review of the drone images. "Perception bias data - Shark Bay Hodgson et al" contains the data used to calculate the perception bias for the observers onboard the piloted aircraft.

Steller's sea cow, an extinct sirenian and one of the largest Quaternary mammals, was described by Georg Steller in 1741 and eradicated by humans within 27 years. Here, we complement Steller's descriptions with paleogenomic data from 12 individuals. We identified convergent evolution between Steller's sea cow and cetaceans but not extant sirenians, suggesting a role of several genes in adaptation to cold aquatic (or marine) environments. Among these are inactivations of lipoxygenase genes, which in humans and mouse models cause ichthyosis, a skin disease characterized by a thick, hyperkeratotic epidermis that recapitulates Steller's sea cows' reportedly bark-like skin. We also found that Steller's sea cows' abundance was continuously declining for tens of thousands of years before their description, implying that environmental changes also contributed to their extinction.

Steller's sea cow, an extinct sirenian and one of the largest Quaternary mammals, was described by Georg Steller in 1741 and eradicated by humans within 27 years. Here, we complement Steller's descriptions with paleogenomic data from 12 individuals. We identified convergent evolution between Steller's sea cow and cetaceans but not extant sirenians, suggesting a role of several genes in adaptation to cold aquatic (or marine) environments. Among these are inactivations of lipoxygenase genes, which in humans and mouse models cause ichthyosis, a skin disease characterized by a thick, hyperkeratotic epidermis that recapitulates Steller's sea cows' reportedly bark-like skin. We also found that Steller's sea cows' abundance was continuously declining for tens of thousands of years before their description, implying that environmental changes also contributed to their extinction.

Extensive home ranges of marine megafauna present a challenge for systematic conservation planning because they exceed spatial scales of conventional management. For elusive species like dugongs, their management is additionally hampered by a paucity of basic distributional information across much of their range. The Red Sea is home to a wide-spread, globally important but data-poor population of dugongs. We surveyed the north-eastern Red Sea in the waters of NEOM, Kingdom of Saudi Arabia, to locate feeding sites and determine priority areas for dugong conservation. We conducted large-scale in-water surveys of dugong feeding trails across 27 seagrass meadows that span 0.7 degree of latitude and recorded nine seagrass species and 13 dugong feeding sites. Spread over ~ 4‚061 km2 of nearshore and offshore waters, many of these sites clustered around five main core feeding areas. Dugong feeding trails were mostly recorded at sites dominated by the fast-growing pioneer seagrasses Halodule uninervis, Halophila ovalis and/or H. stipulacea. Multispecific meadows with pioneer seagrasses tended to be sheltered and shallow, reflecting a similar spatial pattern to the identified dugong feeding sites. Often close to hotels and fishing harbours, these high-use dugong areas are subject to high boat traffic, fishing, and coastal development which places considerable pressures on this vulnerable mammal and its seagrass habitat. The rapidly accelerating coastal development in the northern Red Sea directly threatens the future of its dugong population. Although our sampling focuses on feeding signs in early successional seagrasses, the results are valuable to spatial conservation planning as they will trigger overdue conservation interventions for a globally threatened species in a data-poor area. Urgent dugong conservation management actions in the northern Red Sea should focus on shallow waters sheltered by coastal lagoons, bays and the lee of large islands.

Despite their ecological role and multiple contributions to human societies, the distribution of Indo-Pacific seagrasses remains poorly known in many places. Herein, we outline a hierarchical spatially-explicit assessment framework to derive nation-wide synoptic knowledge of the distribution of seagrass species and communities. We applied the framework to New Caledonia (southwest Pacific Ocean) and its 36,200 km2 of reefs and lagoons. The framework is primarily field-based but can leverage various habitat maps derived from remote sensing. Field data collection can be stratified by map products and retrospectively contribute to developing new seagrass distribution maps. Airborne and satellite remote sensing alone do not allow for the spatial generalisation of the finest attributes (species distribution and types of seagrass beds), but staged stratified field sampling provides synoptic views of these attributes. Using three examples, we discuss how the hierarchical and spatial information generated from this framework's application can inform conservation and management objectives.

Despite their ecological role and multiple contributions to human societies, the distribution of Indo-Pacific seagrasses remains poorly known in many places. Herein, we outline a hierarchical spatially-explicit assessment framework to derive nation-wide synoptic knowledge of the distribution of seagrass species and communities. We applied the framework to New Caledonia (southwest Pacific Ocean) and its 36,200 km2 of reefs and lagoons. The framework is primarily field-based but can leverage various habitat maps derived from remote sensing. Field data collection can be stratified by map products and retrospectively contribute to developing new seagrass distribution maps. Airborne and satellite remote sensing alone do not allow for the spatial generalisation of the finest attributes (species distribution and types of seagrass beds), but staged stratified field sampling provides synoptic views of these attributes. Using three examples, we discuss how the hierarchical and spatial information generated from this framework's application can inform conservation and management objectives.

This is the summary dataset of the dugong seagrass associations data containing dugong counts, benthic habitat cover, seagrass nutrient content, water temperature, water current speed, water depth and water transparency from three locations in the Pilbara over 3 time periods in 2018-2019.

Little is known about how the Vulnerable dugong Dugong dugon uses coral reef lagoons despite the importance of these habitats throughout much of its vast range. We used GPS satellite tracking systems to explore the space use of 12 dugongs at 3 locations in the coral reef lagoons of the main island of New Caledonia in the southwest Pacific: Cap Goulvain, Ouano and Noumea. The movements of the tracked dugongs varied among individuals and all except one animal undertook large-scale movements (>15 km; mean [+/- SE] 37.7 +/- 5.2 km) from their capture location (maximum waterway distance range: 13.8 to 72.9 km). The straight-line distances between the furthest GPS locations during each animal's tracking period ranged from 21.3 to 74.5 km. We identified areas used intensively by dugongs in all 3 study areas, some of which were areas where seagrass presence has not been verified, or where dugongs have not been observed during past aerial surveys. Dugongs spent most of their tracking time within the lagoons, with 99.4% of GPS locations found inside the barrier reef. Nonetheless, where the lagoon was narrow and confined, 3 tracked dugongs used the fore reef shelf outside the barrier reef in the open ocean to commute between bays. Our findings can inform conservation and management initiatives in New Caledonia as well as other countries within the dugong's range which have similar habitat geomorphology but where dugongs occur in numbers too low to be tracked and are considered Critically Endangered.

This is the summary dataset of the dugong seagrass associations data containing dugong counts, benthic habitat cover, seagrass nutrient content, water temperature, water current speed, water depth and water transparency from three locations in the Pilbara over 3 time periods in 2018-2019.

Seagrass meadows support key ecosystem services, via provision of food directly for herbivores, and indirectly to their predators. The importance of herbivores in seagrass meadows has been well-documented, but the links between food webs and ecosystem services in seagrass meadows have not previously been made explicit. Herbivores interact with ecosystem services - including carbon sequestration, cultural values, and coastal protection. Interactions can be positive or negative and depend on a range of factors including the herbivore identity and the grazing type and intensity. There can be unintended consequences from management actions based on a poor understanding of trade-offs that occur with complex seagrass-herbivore interactions. Tropical seagrass meadows support a diversity of grazers spanning the meso-, macro-, and megaherbivore scales. We present a conceptual model to describe how multiple ecosystem services are influenced by herbivore pressure in tropical seagrass meadows. Our model suggests that a balanced ecosystem, incorporating both seagrass and herbivore diversity, is likely to sustain the broadest range of ecosystem services. Our framework suggests the pathway to achieve desired ecosystem services outcomes requires knowledge on four key areas: (1) how size classes of herbivores interact to structure seagrass; (2) desired community and management values; (3) seagrass responses to top-down and bottom-up controls; (4) the pathway from intermediate to final ecosystem services and human benefits. We suggest research should be directed to these areas. Herbivory is a major structuring influence in tropical seagrass systems and needs to be considered for effective management of these critical habitats and their services.

Full Text, Thesis (PhD Doctorate), Doctor of Philosophy (PhD), School of Humanities, Languages and Social Science, Arts, Education and Law, This thesis explores the relationship between Indigenous knowledge and Australian settler perceptions of medicinal practice by examining the manufacturing and use of dugong oil. It tracks the growth of the dugong industry in Moreton Bay in the mid-nineteenth century, before analysing the way in which dugong oil made its way through the hands of medical practitioners into newspaper advertisements and exhibitions from Australia to Europe. At this time, Australia was following Britain in the move to professionalise medicine despite a continuing popularity of heterodox and home treatments. Discoveries‘ of new medicinal remedies by medical professionals blur the lines of orthodox and unorthodox medicine and add another dimension to this history. Specifically, the case of dugong oil, learned from the Indigenous inhabitants, shows the interconnectedness of the dominant and the minority stories, shedding new light on the history of medicine, products, exchange and ideas in the age of empire.

This thesis explores the relationship between Indigenous knowledge and Australian settler perceptions of medicinal practice by examining the manufacturing and use of dugong oil. It tracks the growth of the dugong industry in Moreton Bay in the mid-nineteenth century, before analysing the way in which dugong oil made its way through the hands of medical practitioners into newspaper advertisements and exhibitions from Australia to Europe. At this time, Australia was following Britain in the move to professionalise medicine despite a continuing popularity of heterodox and home treatments. Discoveries‘ of new medicinal remedies by medical professionals blur the lines of orthodox and unorthodox medicine and add another dimension to this history. Specifically, the case of dugong oil, learned from the Indigenous inhabitants, shows the interconnectedness of the dominant and the minority stories, shedding new light on the history of medicine, products, exchange and ideas in the age of empire., Thesis (PhD Doctorate), Doctor of Philosophy (PhD), School of Humanities, Languages and Social Science, Arts, Education and Law, Full Text

The late Pleistocene extinction of so many large-bodied vertebrates has been variously attributed to two general causes: rapid climate change and the effects of humans as they spread from the Old World to previously uninhabited continents and islands. Many large-bodied vertebrates, especially large apex predators, maintain their associated ecosystems through top-down forcing processes, especially trophic cascades, and megaherbivores also exert an array of strong indirect effects on their communities. Thus, a third possibility for at least some of the Pleistocene extinctions is that they occurred through habitat changes resulting from the loss of these other keystone species. Here we explore the plausibility of this mechanism, using information on sea otters, kelp forests, and the recent extinction of Stellers sea cows from the Commander Islands. Large numbers of sea cows occurred in the Commander Islands at the time of their discovery by Europeans in 1741. Although extinction of these last remaining sea cows during early years of the Pacific maritime fur trade is widely thought to be a consequence of direct human overkill, we show that it is also a probable consequence of the loss of sea otters and the co-occurring loss of kelp, even if not a single sea cow had been killed directly by humans. This example supports the hypothesis that the directly caused extinctions of a few large vertebrates in the late Pleistocene may have resulted in the coextinction of numerous other species.

The extent and scope of the seasonal distribution movements and habitat usage of dugongs fitted with remote location recording and transmitting devices within the Shark Bay World Heritage Property (SBWHP) on the mid-West Coast of Western Australia were measured from 2000-2002. In addition to defining movement patterns and habitat preferences of individual dugongs an aerial survey was undertaken during the summer of 2002 to define population distribution and abundance estimates.

The Muk-Talibong Islands in Trang Province is a habitat for the largest group of dugongs on Thailand's Andaman coast. Since 1994, the Phuket Marine Biological Center has regularly conducted aerial surveys over the area with various kinds of aircrafts. In 2011 and 2012, the small aircraft model Tecnum P92J was used in line transect aerial surveys. Survey efforts were four flights (15.01 hours) and seven flights (17.14 hours) respectively. In 2011, the dugong detection rate was 51±50 animals per day, with a maximum count of 122 animals. In 2012, however, the dugong detection rate was 26±14 animals per day, with a maximum count of 54 animals. As a result of comparing the dugong detection rates for both years, we found that the number of dugongs is decreasing, even though the aerial survey periods in each year were the same month and tidal time. Windspeed is likely to be a physical factor that might lead to these results. Ranges of wind speed were 0-6 knot in 2011 and 5-17 knot in 2012. The wind speed affects waves and turbidity, and this may negatively affect visual detection of dugongs. Therefore, further aerial surveys in different weather conditions and dugong stranding reports may help to better understand the declining trends of dugongs in the area., March 18-19, 2013

In this study, we investigate the possibility of measuring fecal progesterone (P4) of dugongs in captivity. Fecal samples were collected from a captive adult female dugong kept at Toba aquarium in November 2012 and February 2013, and fecal P4 of these samples was measured using enzyme immunoassay (EIA). To establish a measuring system, we compared the results of measurements applying different dilution rates of primary antibody and enzyme linked antigen, and decided the best experimental condition for accurate measurement. We then measured P4 concentrations of the dugong’s fecal samples. Significant difference in the P4 concentrations was not found among the samples collected in November and February. Thus it is suggested the dugong was not in estrous period when the samples were collected. We succeeded in extracting and measuring fecal P4 of the dugong, and for further study, we plan to apply this method to monitoring of estrous cycle of dugongs., March 18-19, 2013

The Muk-Talibong Islands in Trang Province is a habitat for the largest group of dugongs on Thailand's Andaman coast. Since 1994, the Phuket Marine Biological Center has regularly conducted aerial surveys over the area with various kinds of aircrafts. In 2011 and 2012, the small aircraft model Tecnum P92J was used in line transect aerial surveys. Survey efforts were four flights (15.01 hours) and seven flights (17.14 hours) respectively. In 2011, the dugong detection rate was 51±50 animals per day, with a maximum count of 122 animals. In 2012, however, the dugong detection rate was 26±14 animals per day, with a maximum count of 54 animals. As a result of comparing the dugong detection rates for both years, we found that the number of dugongs is decreasing, even though the aerial survey periods in each year were the same month and tidal time. Windspeed is likely to be a physical factor that might lead to these results. Ranges of wind speed were 0-6 knot in 2011 and 5-17 knot in 2012. The wind speed affects waves and turbidity, and this may negatively affect visual detection of dugongs. Therefore, further aerial surveys in different weather conditions and dugong stranding reports may help to better understand the declining trends of dugongs in the area.

In this study, we investigate the possibility of measuring fecal progesterone (P4) of dugongs in captivity. Fecal samples were collected from a captive adult female dugong kept at Toba aquarium in November 2012 and February 2013, and fecal P4 of these samples was measured using enzyme immunoassay (EIA). To establish a measuring system, we compared the results of measurements applying different dilution rates of primary antibody and enzyme linked antigen, and decided the best experimental condition for accurate measurement. We then measured P4 concentrations of the dugong’s fecal samples. Significant difference in the P4 concentrations was not found among the samples collected in November and February. Thus it is suggested the dugong was not in estrous period when the samples were collected. We succeeded in extracting and measuring fecal P4 of the dugong, and for further study, we plan to apply this method to monitoring of estrous cycle of dugongs.

Two dugongs, Dugong dugon (Muller, 1976), were accidentally entangled in fishing nets in Barangay Dahican, Mati City, Southeastern Mindanao, Philippines. These dugongs, 2.2 and 2.5m in length and 172 and 132.5kg in weight respectively, were necropsied in January and February 2011, and a parasitological examination was conducted on each. From one dugong, adult roundworms, Paradujardinia halicoris and trematodes, Solenorchis travassosi (syn. Indosolenorchis hirudinaceus) were recovered from the stomach or small intestine and caecum respectively. From the other, juvenile roundworms were found in the stomach and small intestine. Female adults were 104.7mm long and 3.1mm wide on average, whereas male adults were similarly 97.6mm long and 2.8mm wide. Scanning Electron Microscopy (SEM) of P. halicoris showed that this nematode had three well-defined lips, longer than the width, with small triangular interlabia between them, distinctly offset from the anterior end. A few trematodes, S. travassosi, were 10.3mm long and 3.1mm wide on average with a tiny oral sucker and a large posterior sucker subterminally located at both extremities. The posterior extremity has a distinct crescent-like muscular projection on its end. This is the first confirmed record of two helminth species from dugongs around Mindanao Island., February 20-21, 2012, BANGKOK, THAILAND

Two dugongs, Dugong dugon (Muller, 1976), were accidentally entangled in fishing nets in Barangay Dahican, Mati City, Southeastern Mindanao, Philippines. These dugongs, 2.2 and 2.5m in length and 172 and 132.5kg in weight respectively, were necropsied in January and February 2011, and a parasitological examination was conducted on each. From one dugong, adult roundworms, Paradujardinia halicoris and trematodes, Solenorchis travassosi (syn. Indosolenorchis hirudinaceus) were recovered from the stomach or small intestine and caecum respectively. From the other, juvenile roundworms were found in the stomach and small intestine. Female adults were 104.7mm long and 3.1mm wide on average, whereas male adults were similarly 97.6mm long and 2.8mm wide. Scanning Electron Microscopy (SEM) of P. halicoris showed that this nematode had three well-defined lips, longer than the width, with small triangular interlabia between them, distinctly offset from the anterior end. A few trematodes, S. travassosi, were 10.3mm long and 3.1mm wide on average with a tiny oral sucker and a large posterior sucker subterminally located at both extremities. The posterior extremity has a distinct crescent-like muscular projection on its end. This is the first confirmed record of two helminth species from dugongs around Mindanao Island.

The dugong trenches in the coast of Iriomote Island were investigated. The luxuriance of seagrasses in the western coast of Iriomote Island was higher than seagrasses in Okinawa Island. And many kinds of species of the seagrasses were observated (two family, six genus, eight species). The field investigated in this time was more large area and very well. Therefore, the side of diversity of living thing, the western coast of Iriomote Island was most important area. And, this coast has profusion of the Food of dougong dugon. But in this investigation, we were not able to check dugong trench in the coast of Iriomote Island. Therefore, it was guessed that a possibility that, as for us, the dugong inhabits the Iriomote island was low., 西表島周辺におけるジュゴンの定着の可能性について調査する目的で、ジュゴンによる食痕調査およびジュゴンに関する伝聞や目撃情報などの聞き取り調査を行った。食痕調査では4地域を行った。また、聞き取り調査では石垣島およひ西表島で計41名を対象に行った。ジュゴンの食痕調査では、いずれの地域においてもジュゴンによる食痕は確認できなかった。また、ジュゴンの目撃に関する情報は、石垣島およひ西表島ともに全くなかった。伝聞に関しては30件の情報を得た。このようなことから、今回のジュゴンの食痕調査および聞き取り調査から、現在は西表島周辺にジュゴンは定着していないと思われた。しかし、かつてジュゴンが棲息していた地域における海草藻場の広がりは極めて良好であり、南西諸島海洋の生物多様性の面からも非常に重要な地域である。西表島西岸は、定期船の往来も少なく、良好な藻場を有していることから、西表島におけるジュゴン定着の可能性は極めて高いものと推察された。

The Union of Myanmar is one of the first signatory states of the Memorandum of Understanding on the Conservation and Management of Dugongs and Their Habitats Throughout Their Range. Dugong trails were observed on seagrass beds of Lampi and Nyaung Wee Islands of the Myeik Archipelago in Tanintharyi Region in Southern Myanmar. Occurrence of dugongs in Tanintharyi Region was reported by local people. These are important messages to formulate dugong conservation and management in Myanmar. Dugongs have been protected by Law since 1994 and they are placed under the "Completely Protected Animals" category. Effective conservation activities on dugong have not been carried out by Myanmar yet. Lack of promotion in effective and scientific management of terrestrial and marine protected areas to meet representative samples of ecosystems, particularly to marine and coastal, is a major challenge encountered pertaining to biodiversity conservation in Myanmar. Furthermore, development of a National Biodiversity Strategy and Action Plan (NBSAP) and its implementation is an urgent need of Myanmar., March 8-9, 2011, BANGKOK, THAILAND

This thesis explores the conflict between conservationists and Indigenous communities over the hunting of marine turtles and dugong in Australia, with a view to finding a way to overcome the barriers that prevent the resolution of this issue. I approached this exploration as an ecologist, using the framework of Berkes (2004) who proposed three shifts for the field of ecology. This meant taking a systems approach and investigating the intertwining threads of the issue as possible, with a specific focus on integrating the human aspects of the problem in a participatory manner. By doing so my work entered into a third space where multiple possibilities for investigation opened up. Through listening to others with expertise on the matter (from both Indigenous and non-Indigenous cultures) I have created a hybrid account of the ecology of marine turtles and dugong in Australia. The methodology used in undertaking this research was reflexive in nature, with a focus upon both my own and Bardi and Jawi culture, utilising interviews and participant observation as my primary methods of data collection. Wherever possible, a collaborative and participatory approach to the research was undertaken, with many people assisting me in my growing understandings of this issue. I have made use of various text-based resources, including the current scientific literature, historical accounts and records and my own field diaries to support the interview data that I collected. This account traces the origins of the conflict over marine turtle and dugong in Australia and focuses on a few key moments where attempts to resolve the issue have occurred over the past twenty years. By viewing these moments through the lens of the ecological discourses described by Manuel-Naverrete et al. (2008), it can be seen that progress towards the resolution of the conflict is unlikely to occur when participants retain a strongly normative worldview, and that movement towards an ecosystemic-pluralistic framewo

The Union of Myanmar is one of the first signatory states of the Memorandum of Understanding on the Conservation and Management of Dugongs and Their Habitats Throughout Their Range. Dugong trails were observed on seagrass beds of Lampi and Nyaung Wee Islands of the Myeik Archipelago in Tanintharyi Region in Southern Myanmar. Occurrence of dugongs in Tanintharyi Region was reported by local people. These are important messages to formulate dugong conservation and management in Myanmar. Dugongs have been protected by Law since 1994 and they are placed under the "Completely Protected Animals" category. Effective conservation activities on dugong have not been carried out by Myanmar yet. Lack of promotion in effective and scientific management of terrestrial and marine protected areas to meet representative samples of ecosystems, particularly to marine and coastal, is a major challenge encountered pertaining to biodiversity conservation in Myanmar. Furthermore, development of a National Biodiversity Strategy and Action Plan (NBSAP) and its implementation is an urgent need of Myanmar.

The loss of large-bodied herbivores and/or top predators has been associated with large-scale changes in terrestrial, freshwater, and marine ecosystems around the world. Understanding the consequences of these declines has been hampered by a lack of studies in relatively pristine systems. To fill this gap, I investigated the dynamics of the relatively pristine seagrass ecosystem of Shark Bay, Australia. I began by examining the seagrass species distributions, stoichiometry, and patterns of nutrient limitation across the whole of Shark Bay. Large areas were N-limited, P-limited, or limited by factors other than nutrients. Phosphorus-limitation was centered in areas of restricted water exchange with the ocean. Nutrient content of seagrasses varied seasonally, but the strength of seasonal responses were species-specific. Using a cafeteria-style experiment, I found that fast-growing seagrass species, which had higher nutrient content experienced higher rates of herbivory than slow-growing species that are dominant in the bay but have low nutrient content. Although removal rates correlated well with nutrient content at a broad scale, within fast-growing species removal rates were not closely tied to N or P content. Using a combination of stable isotope analysis and animal borne video, I found that green turtles (Chelonia mydas) – one of the most abundant large-bodied herbivores in Shark Bay – appear to assimilate little energy from seagrasses at the population level. There was, however, evidence of individual specialization in turtle diets with some individuals foraging largely on seagrasses and others feeding primarily on macroalgae and gelatinous macroplankton. Finally, I used exclusion cages, to examine whether predation-sensitive habitat shifts by megagrazers (green turtles, dugongs) transmitted a behavior-mediated trophic cascade (BMTC) between sharks and seagrasses. In general, data were consistent with predictions of a behavior-mediated trophic cascade. Megaherbiv

The study aimed to (a) provide record of dugong stranding and mortality, (b) conduct necropsy of dugong, (c) characterize the circumstantial causes of mortality and stranding and (d) determine the threats that impede dugong conservation.Secondary data available on strandings and mortality of dugong were utilized to confirm validity of data obtained from interview of fishfarmers. Record of logged and reported incidents of dugong strandings and mortality were also retrieved. Necropsy was done every time dugong mortality occurred. Information and data were kept in dugong data sheets. Preliminary results showed that from 2001 – 2008, six strandings of dugongs have been documented in Malita, Davao del Sur. All the six strandings occurred within an approximate 10 km stretch of coastline (from Brgy. Lacaron to Brgy. Tingolo) of Malita, Davao del Sur. One out of the six strandings was a female baby dugong. The other four were male adult dugong with a length of not less than 2m. The probable causes of death were mostly anthropogenic: victim of spear fishing, blasting, entangled in net and intentionally caught for food. Parasitism was also observed in one of the dugongs that was examined where the gut, stomach, intestine were heavily infested with round worms., February 23-25, 2010, Phuket, Thailand

Ocean noise has a possibility to interfere with acoustic communication of marine mammals by masking biological signals. Some species of marine mammals change their vocalization (e.g., increasing amplitude, duration, repetition and shifting frequency) with elevated ambient noise level to avoid acoustic interference. We studied the dial pattern of ambient noise and dugong calls. We used the underwater sound data recorded off the south coast of Talibong Island, Trang, Thailand, by Automatic Underwater SOund Monitoring System for Dugong (AUSOMS-D). We used the data recorded from 10:00h on November 16 to 9:00h November 23, 2006. To quantify the dial pattern of the ambient noise, hourly ambient noise levels were analyzed. Then, we counted the number of dugong calls and analyzed their acoustic characteristics. Finally, we tested the relationship between the peak frequency of calls and the ambient noise level to investigate whether and how dugongs change their vocalizations. We found high ambient noise levels in the morning through noon (6:00-12:00h) and evening (18:00-21:00h). Dugongs calls were frequently observed at night as described in previous studies. Dugongs call showed the high frequency (6-9 kHz) with elevated level of the ambient noise, while they usually use 3-6 kHz call. Dugongs may adapt their vocalization in relation to the continuous ambient noise., February 23-25, 2010, Phuket, Thailand

The study aimed to (a) provide record of dugong stranding and mortality, (b) conduct necropsy of dugong, (c) characterize the circumstantial causes of mortality and stranding and (d) determine the threats that impede dugong conservation.Secondary data available on strandings and mortality of dugong were utilized to confirm validity of data obtained from interview of fishfarmers. Record of logged and reported incidents of dugong strandings and mortality were also retrieved. Necropsy was done every time dugong mortality occurred. Information and data were kept in dugong data sheets. Preliminary results showed that from 2001 – 2008, six strandings of dugongs have been documented in Malita, Davao del Sur. All the six strandings occurred within an approximate 10 km stretch of coastline (from Brgy. Lacaron to Brgy. Tingolo) of Malita, Davao del Sur. One out of the six strandings was a female baby dugong. The other four were male adult dugong with a length of not less than 2m. The probable causes of death were mostly anthropogenic: victim of spear fishing, blasting, entangled in net and intentionally caught for food. Parasitism was also observed in one of the dugongs that was examined where the gut, stomach, intestine were heavily infested with round worms.

Ocean noise has a possibility to interfere with acoustic communication of marine mammals by masking biological signals. Some species of marine mammals change their vocalization (e.g., increasing amplitude, duration, repetition and shifting frequency) with elevated ambient noise level to avoid acoustic interference. We studied the dial pattern of ambient noise and dugong calls. We used the underwater sound data recorded off the south coast of Talibong Island, Trang, Thailand, by Automatic Underwater SOund Monitoring System for Dugong (AUSOMS-D). We used the data recorded from 10:00h on November 16 to 9:00h November 23, 2006. To quantify the dial pattern of the ambient noise, hourly ambient noise levels were analyzed. Then, we counted the number of dugong calls and analyzed their acoustic characteristics. Finally, we tested the relationship between the peak frequency of calls and the ambient noise level to investigate whether and how dugongs change their vocalizations. We found high ambient noise levels in the morning through noon (6:00-12:00h) and evening (18:00-21:00h). Dugongs calls were frequently observed at night as described in previous studies. Dugongs call showed the high frequency (6-9 kHz) with elevated level of the ambient noise, while they usually use 3-6 kHz call. Dugongs may adapt their vocalization in relation to the continuous ambient noise.

Dugong is known as Ye wet (= Water pig) and Ye thu ma (= Mermaid) in Myanmar. Man Aung Island, about 55 miles in circumference, is situated at 18°47.898'N and 93°98.472'E in the Rakhine Coast of western Myanmar. It was known as Cheduba Island as an English name in the past. Dugongs live in shallow, near shore waters of north, east and south-eastern Man Aung. Dugongs are sighted mostly in the raining season. They particularly like Halophila ovalis seagrass species. Usually solitary but they could also be found in groups of two to three animals. They love their family, especially their “child”, very much. Fishermen are of the opinion that dugongs make a cough-like sound, “a hoot, a hoot, …”, in the water. The mating season of dugong occurs in the transitional period between the end of the rainy season and start of the winter. Dugong meat and bones are used as traditional medicine. Dugongs are protected by Law. Accidental mortality in fishing nets is still prevalent. Geographic position and nature attributes around the island prevail the occurrence of dugongs. Man Aung Island definitely deserves to be nominated as a place for focusing future activities on dugong research and conservation in Myanmar., March 5-6, 2009, Bangkok, Thailand

Dugongs (Dugong dugon) are seen in limited areas along both coastlines of Thailand, the Andaman Sea and the Gulf of Thailand. Thai researchers have been studying the dugong since 1979. Information on the history of dugongs, beliefs, and the previous use of dugong body parts in Thailand has been gathered from interviews with local people along both coastlines since 1994. Within Thailand various village names and other locations have been derived from the various names of the dugong in the Thai language. Currently, the local belief in magical properties of dugongs are not as strong as in the past, but items made of dugong body parts have been found, especially along the coast of the Andaman Sea. Scientists are making an effort to utilize traditional ecological knowledge on the conservation and management of dugong and other marine endangered animals. It is likely that traditional ecological knowledge would play an important role in conservation and management of dugong and biodiversity in Thailand in the future., March 5-6, 2009, Bangkok, Thailand

Six stomachs of stranded dugongs, collected in Trang Province, Thailand during January 1997- January 1999, were inspected. Based on physio/morphological characters of leaves and epidermal cells, seagrass fragments were identified down to species under stereo - and compound-microscopes. Nine species of six genera of seagrasses were found in dugong stomachs, 4-6 species each and their biomass was determined in terms of dry weight. The percentage dry weight of each species found in the stomach contents was as follows: Halodule spp. 0.84-44.99%, Halophila ovalis 3.11-29.60%, Thalassia hemprichii 3.50-28.69%, Cymodocea spp. 5.06-42.52%, Syringodium isoetifolium 0.42- 22.39%, and Enhalus acoroides 31.76-41.39%. The biomass of Halophila decipiens was not determined because of its scarcity. Four dugongs fed mainly on the dominant species (H. ovalis, E. acoroides, Cymodocea. serrulata, and Halodule pinifolia) available in the catch areas whereas the another two dugongs may have selected their target seagrasses from the existing species. Rhizome appeared to be the importance part of dugong dietary. Remarkably, the dominant available seagrass species in the catch areas contributed to be the most heavily utilized genera of the dugongs in Trang waters., March 5-6, 2009, Bangkok, Thailand

Dugong is known as Ye wet (= Water pig) and Ye thu ma (= Mermaid) in Myanmar. Man Aung Island, about 55 miles in circumference, is situated at 18°47.898'N and 93°98.472'E in the Rakhine Coast of western Myanmar. It was known as Cheduba Island as an English name in the past. Dugongs live in shallow, near shore waters of north, east and south-eastern Man Aung. Dugongs are sighted mostly in the raining season. They particularly like Halophila ovalis seagrass species. Usually solitary but they could also be found in groups of two to three animals. They love their family, especially their “child”, very much. Fishermen are of the opinion that dugongs make a cough-like sound, “a hoot, a hoot, …”, in the water. The mating season of dugong occurs in the transitional period between the end of the rainy season and start of the winter. Dugong meat and bones are used as traditional medicine. Dugongs are protected by Law. Accidental mortality in fishing nets is still prevalent. Geographic position and nature attributes around the island prevail the occurrence of dugongs. Man Aung Island definitely deserves to be nominated as a place for focusing future activities on dugong research and conservation in Myanmar.

Six stomachs of stranded dugongs, collected in Trang Province, Thailand during January 1997- January 1999, were inspected. Based on physio/morphological characters of leaves and epidermal cells, seagrass fragments were identified down to species under stereo - and compound-microscopes. Nine species of six genera of seagrasses were found in dugong stomachs, 4-6 species each and their biomass was determined in terms of dry weight. The percentage dry weight of each species found in the stomach contents was as follows: Halodule spp. 0.84-44.99%, Halophila ovalis 3.11-29.60%, Thalassia hemprichii 3.50-28.69%, Cymodocea spp. 5.06-42.52%, Syringodium isoetifolium 0.42- 22.39%, and Enhalus acoroides 31.76-41.39%. The biomass of Halophila decipiens was not determined because of its scarcity. Four dugongs fed mainly on the dominant species (H. ovalis, E. acoroides, Cymodocea. serrulata, and Halodule pinifolia) available in the catch areas whereas the another two dugongs may have selected their target seagrasses from the existing species. Rhizome appeared to be the importance part of dugong dietary. Remarkably, the dominant available seagrass species in the catch areas contributed to be the most heavily utilized genera of the dugongs in Trang waters.

Dugongs (Dugong dugon) are seen in limited areas along both coastlines of Thailand, the Andaman Sea and the Gulf of Thailand. Thai researchers have been studying the dugong since 1979. Information on the history of dugongs, beliefs, and the previous use of dugong body parts in Thailand has been gathered from interviews with local people along both coastlines since 1994. Within Thailand various village names and other locations have been derived from the various names of the dugong in the Thai language. Currently, the local belief in magical properties of dugongs are not as strong as in the past, but items made of dugong body parts have been found, especially along the coast of the Andaman Sea. Scientists are making an effort to utilize traditional ecological knowledge on the conservation and management of dugong and other marine endangered animals. It is likely that traditional ecological knowledge would play an important role in conservation and management of dugong and biodiversity in Thailand in the future.

The Ryukyu Archipelago of Japan is the northern limit of the distribution of the dugong (Dugong dugon), and populations in Japanese waters are small. Therefore, little biological information is available on local dugong, and new specimens or techniques are necessary to help shed light on the populations of this region. We assessed the suitability of using ancient dugong bones collected from ruins on Shimoji Island, in the Yaeyama Islands, for biological investigations. We collected more than 1, 000 fragments of animal bone at the site. From these, we were able to reconstruct 91 dugong skulls, from which we estimated body length (124.2–301.2 cm) and age group compositions (43% adults, 29% adolescents, and 16% juveniles). Our estimation revealed a wide range of age groups, from neonates to mature adults. These results suggest that the ancient dugong population bred and spent all life stages along the coasts of the Yaeyama Islands. Moreover, our study shows that these ancient bones can be used for meaningful biological investigations on dugong, and should help to elucidate their historical distribution and population structure in this area., December 15-17, 2007, Royal Phuket City Hotel, Phuket, Thailand

The information of stranded dugongs (Dugong dugon) has been recorded by the Phuket Marine Biological Center from the Andaman Sea coast and the Gulf of Thailand. The data were obtained from the records of fishermen, stranded dugongs, and specimens preserved in the museums, temples or institutions. Two hundred and eighty two records of stranded dugong were recovered from 1962 through February 2008. Of these 71.6% of the records were from the Andaman Sea, 25.8% of the records from the Gulf and 2.6% of the records had no information of the stranding place. Some 22.7% of the records were male, 22.3% female and 55.0 % of unidentified sex. The highest record of stranded dugong per year was in 1996 and the place where most stranding was found was in Trang province. The mean length of stranded mature dugong was 2.52±0.18 m in male (n=12) and 2.5±0.16 in female (n=19) while the maximum length was 2.94 m. The smallest calf was 0.97 m in length and 14 kg in weight. The maximum weight of 310 kg was recorded in a male dugong with 2.75 m in body length. The number of stranding sizes of the dugong ranging from 0-1.5 m long, >1.5-2.0 m long and >2.0-3.0 m long was 20.8%, 31.7% and 47.5%, respectively (n=101). The body length (m) and body weight (kg) relationship equation was Y = 19.108 x 2.8103 and R = 0.945 (n=65). Most dugongs died by unidentified cause. However a generally high proportion of deaths was from gillnets among identified causes of the stranding., December 15-17, 2007, Royal Phuket City Hotel, Phuket, Thailand

An acoustical approach for research on marine mammals has been a very active research method in recent years. Dugong (Dugong dugon) is one of the highly endangered species, which are strictly-marine herbivorous and mainly inhabit coastal areas. In order to detect dugong calls from recorded data, several algorithms have been adapted by researchers in the analyzing process. However, the number of misses in the detection is still non-zero. The sound of snapping shrimp recorded in a wide range (2-300 kHz) is one of the main background noises that makes the detection of dugong calls difficult in warm shallow waters. Impulse elimination was employed in the system to get rid of the snapping shrimp noise. In order to improve the performance of the detection system by increasing the detection rate and decreasing the number of misses, two new algorithms were tested in the experiment. The experimental results for the new algorithms including impulse elimination and the cepstrum method are presented in this paper.

The Ryukyu Archipelago of Japan is the northern limit of the distribution of the dugong (Dugong dugon), and populations in Japanese waters are small. Therefore, little biological information is available on local dugong, and new specimens or techniques are necessary to help shed light on the populations of this region. We assessed the suitability of using ancient dugong bones collected from ruins on Shimoji Island, in the Yaeyama Islands, for biological investigations. We collected more than 1, 000 fragments of animal bone at the site. From these, we were able to reconstruct 91 dugong skulls, from which we estimated body length (124.2–301.2 cm) and age group compositions (43% adults, 29% adolescents, and 16% juveniles). Our estimation revealed a wide range of age groups, from neonates to mature adults. These results suggest that the ancient dugong population bred and spent all life stages along the coasts of the Yaeyama Islands. Moreover, our study shows that these ancient bones can be used for meaningful biological investigations on dugong, and should help to elucidate their historical distribution and population structure in this area.

The information of stranded dugongs (Dugong dugon) has been recorded by the Phuket Marine Biological Center from the Andaman Sea coast and the Gulf of Thailand. The data were obtained from the records of fishermen, stranded dugongs, and specimens preserved in the museums, temples or institutions. Two hundred and eighty two records of stranded dugong were recovered from 1962 through February 2008. Of these 71.6% of the records were from the Andaman Sea, 25.8% of the records from the Gulf and 2.6% of the records had no information of the stranding place. Some 22.7% of the records were male, 22.3% female and 55.0 % of unidentified sex. The highest record of stranded dugong per year was in 1996 and the place where most stranding was found was in Trang province. The mean length of stranded mature dugong was 2.52±0.18 m in male (n=12) and 2.5±0.16 in female (n=19) while the maximum length was 2.94 m. The smallest calf was 0.97 m in length and 14 kg in weight. The maximum weight of 310 kg was recorded in a male dugong with 2.75 m in body length. The number of stranding sizes of the dugong ranging from 0-1.5 m long, >1.5-2.0 m long and >2.0-3.0 m long was 20.8%, 31.7% and 47.5%, respectively (n=101). The body length (m) and body weight (kg) relationship equation was Y = 19.108 x 2.8103 and R = 0.945 (n=65). Most dugongs died by unidentified cause. However a generally high proportion of deaths was from gillnets among identified causes of the stranding.

Research Need and Objective : Many sections of the northern WA coastline have become heavily industrialised in the last three decades particularly throughout the Pilbara region where offshore and onshore oil and gas exploration and processing facilities are abundant. There have been recent moves to develop similar industry along the Kimberley coast to access the Browse Basin, a 140,000 Km2 offshore gas field approximately 300km off the Kimberley Coast. This has resulted in extensive debate and the need to define the natural values of this region, which is considered to be one of the world’s most ecologically diverse (WWF 2008). Given the remoteness of the Kimberley and the costs involved in undertaking research programs in this region, desktop studies of unpublished data are a valuable first step in defining natural values. While unpublished dugong distribution and abundance datasets may not be standardised or provide the capacity for detailed analysis they can provide useful historical snapshots with which to focus future research needs. This data report reproduces hard copy format maps and summary data collected in two programmes: 1. Estimates of dugong abundance and distribution in the West Kimberley region collected during preliminary assessment surveys conducted by Dr RIT Prince in 1984 and a series of strip transect aerial surveys throughout 1985; and 2. A longitudinal dataset of incidental observations from 1996-2007, covering both the west and east Kimberley collected by the Australian Customs Service. The strip transect surveys and incidental observation datasets have been entered into a GIS framework with associated metadata. A full description of the methodologies used in the collection of these datasets as well as the processes involved in incorporating them into a GIS framework are listed.

The extent and scope of the seasonal distribution movements and habitat usage of dugongs fitted with remote location recording and transmitting devices within the Shark Bay World Heritage Property (SBWHP) on the mid-West Coast of Western Australia were measured from 2000-2002. In addition to defining movement patterns and habitat preferences of individual dugongs an aerial survey was undertaken during the summer of 2002 to define population distribution and abundance estimates.

Effects of man-made, low-frequency sounds on the behavior of the dugong are discussed in this paper. We developed a monitoring system of power-driven vessel to assess the impact of man-made noise on dugongs. Ship navigation was monitored by questionnaire for boaters and visual observations from an anchored vessel. We used automatic under water sound monitoring systems for dugongs (AUSOMS-D) to record under water sound and to track ship navigations acoustically. The visual observations were performed for a total of 10 hours and 20 minutes and 72 ships were detected. The acoustic monitoring was conducted for over 81 hours and detected 258 ships. Shortest distance between the visual-observation platform and the power-driven vessels ranged from 18 to 500 m or more. We calculated the monitoring range of the system by comparing the result of the visual observation and the acoustic survey. The system detected 51.4 % of noise-making ships within 500 meters from the observation platform, and 78.1 %, 89.5 %, and 100 % within 300, 200, and 100 meters, respectively. The ship navigation showed bimodal occurrence during 6:00-7:00 and during 15:00-17:00. We could position the sound source of ship sounds and draw the pathway of a ship by using AUSOMS-D. Based on this result, we calculated the position fix accuracy of ship sound, which was 17.1±8.71 m. This study provided information on detailed techniques for tracking the noise-making vessels and will lead to tracking the vocalizing animal, such as the dugong., December 13-14, 2006, Siam City Hotel, Bangkok, Thailand