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Janet M. Lanyon - One of the best experts on this subject based on the ideXlab platform.
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comparison of i stat with traditional laboratory analysers in the measurement of blood analytes from field captured Dugongs Dugong Dugon
Aquatic Mammals, 2018Co-Authors: Arthur Wong, Helen L. Sneath, Janet M. Lanyon, Graham R Leggatt, Lucy WoolfordAbstract:Point-of-care (POC) testing is useful in field health assessments of wildlife when the condition of the captured animal must be immediately assessed and/or the location is remote from analytical laboratories. However, prior to their incorporation into clinical health assessment, POC devices must be assessed for potential measurement biases. In this study, the i-STAT (R) portable blood analyser was used to evaluate electrolytes (Na, K, and Cl), glucose, creatinine, lactate, urea, and haematocrit (Hct) of 85 apparently healthy Dugongs (Dugong Dugon) during field health assessments off the coast of southern Queensland, Australia. Blood levels of analytes measured by i-STAT (R) were compared to values reported by the Beckman Coulter AU400 (R) and AU680 (R) automated chemistry analysers, and the Sysmex XT-2000i (TM) (for Het). Lactate and urea values were outside i-STAT (R)'s detectable limits. Bland-Altman plots identified constant biases for all measurable analytes except Het. For most analytes, i-STAT (R) measurements did not show strong agreement with laboratory analysers; differences between paired measurements fell within calculated precision-based acceptance limits less than 75% of the time. Reference intervals for electrolytes, glucose, creatinine, and haematocrit as measured by i-STAT (R) are reported; however, these must be interpreted in light of measurement biases detected when compared with reference analysers.
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Hematology of Dugongs (Dugong Dugon) in southern Queensland
Veterinary Clinical Pathology, 2015Co-Authors: Lucy Woolford, Arthur Wong, Helen L. Sneath, Trevor Long, Susan P. Boyd, Janet M. LanyonAbstract:Background: Little is known of the hematology of the Dugong (Dugong Dugon), a secretive and endangered coastal marine mammal. Objectives: This paper reports hematologic reference intervals (RI) for Dugongs and characterizes morphologic, cytochemical, and ultrastructural features of Dugong leukocytes. Methods: Blood was collected from live, apparently healthy Dugongs and analyzed using Cell-Dyn 3700 or Sysmex XT-2000iV hematology analyzers. Blood films were subjected to a series of cytochemical stains, and leukocyte structure was examined using transmission electron microscopy. Results: Reference intervals were established for 14 hematologic variables, total solids, and fibrinogen for 92 Dugongs. Significant differences in some variables were found for animal size class, sex, and pregnancy status, and between analyzers. Subadults had higher leukocyte and lymphocyte counts than adults. Males had higher total solids and fibrinogen than females. Pregnant females had higher HCT, MCV, and circulating nucleated RBC, and lower platelet counts than nonpregnant females. Lymphocytes were usually the predominant circulating leukocyte. Heterophil cytoplasmic granules were abundant, fine, round to ovoid, and intensely eosinophilic, and round to ovoid or rod-shaped, and variably electron dense in electron microscopy. Eosinophils contained larger round eosinophilic to orange cytoplasmic granules, which ultrastructurally were bicompartmental with a round eccentric electron-dense core. Cytochemical staining of Dugong heterophils suggests biochemical similarity to those of manatees and elephants, and for eosinophils, similarity to those of elephants, ruminants, and equids. Conclusions: Generation of hematologic RI and characterization of leukocyte morphology improves evaluation of Dugong health across this population and serves as a reference for other populations outside southern Queensland.
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serum biochemistry reference intervals of live wild Dugongs Dugong Dugon from urban coastal australia
Veterinary Clinical Pathology, 2015Co-Authors: Janet M. Lanyon, Arthur Wong, Trevor Long, Lucy WoolfordAbstract:Background Little is known about the baseline clinical pathology of the Dugong (Dugong Dugon), a vulnerable marine mammal found in tropical coastal marine systems. Objectives The purpose of the study was to collect and determine reference intervals (RI) for select serum biochemical variables for Dugongs, and to analyze differences between males and females and different age groups. Methods Reference intervals were established from 103 apparently healthy, wild-caught Dugongs for 31 analytes using a Beckman Coulter AU400 Automated Chemistry Analyzer and an Olympus AU680 Chemistry-Immuno Analyzer. Results Significant differences (P < .05) in some of the variables were found related to size class, sex, and pregnancy status. Adult Dugongs had higher serum sodium, potassium, bicarbonate, glucose, and l-lactate concentrations and higher anion gap, compared to sub-adults. Male Dugongs had higher triglyceride and l-lactate concentrations than females. Pregnant females displayed higher l-lactate levels compared to nonpregnant animals. Statistical differences in variables within the population contributed to better understanding of the physiologic differences between cohorts. Some serum biochemistry changes observed in this study here also potentially include some effects of pursuit on Dugongs (eg, higher l-lactate); however, as all Dugongs were subject to similar capture and handling, serum biochemistry RI should be considered as normal for captured Dugongs. Conclusions The serum biochemical RI documented here are considered representative of a population of healthy captured Dugongs. They provide a baseline for health surveillance of this and other Dugong populations.
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pathological findings in wild harvested Dugongs Dugong Dugon of central torres strait australia
Diseases of Aquatic Organisms, 2015Co-Authors: Lucy Woolford, Craig E Franklin, T Whap, F Loban, Janet M. LanyonAbstract:The Dugong Dugong Dugon is classified as Vulnerable to extinction but may be endangered in some regions. Cause of death in stranded Dugongs has not been determined in a large proportion of animals examined, with investigations hindered by limited information on Dugong health and diseases, and paucity of knowledge of common or endemic pathological findings. Here we describe pathological findings in harvested Dugongs from the relatively pristine area of central Torres Strait, and we characterise lesions attributable to drowning. Other recorded lesions were mild and predominated by host reaction to the presence of trematodes within the gastrointestinal tracts, liver and pancreas. Ascarid worm burdens were low in comparison to Dugongs from developed coastlines. Hepatocellular lipofuscin and ferritin pigmentation were commonly observed, more pronounced in livers of older animals and concurrent with periportal and bridging fibrosis. Lesions attributable to drowning included incomplete collapse of lungs, dorsal or diffuse pulmonary congestion, mild intra-alveolar haemorrhage and oedema, mild interstitial oedema and rupture of peripheral alveolar septae with acute myofibre fragmentation and degeneration. No accumulation of foam or aspiration of water or particulate matter was observed, suggesting that Dugongs 'dry drown'. Morphometric features of normal spleen are also presented. Characterisation of common pathological findings and those attributable to drowning in this species will aid in the interpretation of post mortem findings for the significant number of Dugongs found deceased along urbanised coastlines.
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Fine scale population structure of Dugongs (Dugong Dugon) implies low gene flow along the southern Queensland coastline
Conservation Genetics, 2014Co-Authors: Jennifer M. Seddon, Damien Broderick, Jennifer R. Ovenden, Helen L. Sneath, Christine L. Dudgeon, Janet M. LanyonAbstract: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_ST ranged from 0.005 to 0.040 and Jost’s D_EST 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_ST 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.
Damien Broderick - One of the best experts on this subject based on the ideXlab platform.
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Fine scale population structure of Dugongs (Dugong Dugon) implies low gene flow along the southern Queensland coastline
Conservation Genetics, 2014Co-Authors: Jennifer M. Seddon, Damien Broderick, Jennifer R. Ovenden, Helen L. Sneath, Christine L. Dudgeon, Janet M. LanyonAbstract: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_ST ranged from 0.005 to 0.040 and Jost’s D_EST 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_ST 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.
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characterization of highly informative cross species microsatellite panels for the australian Dugong Dugong Dugon and florida manatee trichechus manatus latirostris including five novel primers
Molecular Ecology Resources, 2010Co-Authors: Margaret Kellogg Hunter, Kimberly Pause Tucker, Damien Broderick, Peter M Mcguire, Robert K Bonde, Jennifer R. Ovenden, Janet M. LanyonAbstract:The Australian Dugong (Dugong Dugon) and Florida manatee (Trichechus manatus latirostris) are threatened species of aquatic mammals in the order Sirenia. Sirenian conservation and management actions would benefit from a more complete understanding of genetic diversity and population structure. Generally, species-specific microsatellite markers are employed in conservation genetic studies; however, robust markers can be difficult and costly to isolate. To increase the number of available markers, Dugong and manatee microsatellite primers were evaluated for cross-species amplification. Furthermore, one manatee and four Dugong novel primers are reported. After polymerase chain reaction optimization, 23 (92%) manatee primers successfully amplified Dugong DNA, of which 11 (48%) were polymorphic. Of the 32 Dugong primers tested, 27 (84%) yielded product in the manatee, of which 17 (63%) were polymorphic. Dugong and manatee primers were compared and the most informative markers were selected to create robust and informative marker-panels for each species. These cross-species microsatellite marker-panels can be employed to assess other sirenian populations and can provide beneficial information for the protection and management of these unique mammals.
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sexing sirenians validation of visual and molecular sex determination in both wild Dugongs Dugong Dugon and florida manatees trichechus manatus latirostris
Aquatic Mammals, 2009Co-Authors: Janet M. Lanyon, Damien Broderick, Jennifer R. Ovenden, Helen L. Sneath, Robert K BondeAbstract:Sexing wild marine mammals that show little to no sexual dimorphism is challenging. For sirenians that are difficult to catch or approach closely, molecular sexing from tissue biopsies offers an alternative method to visual discrimination. This paper reports the results of a field study to validate the use of two sexing methods: (1) visual discrimination of sex vs (2) molecular sexing based on a multiplex PCR assay which amplifies the male-specific SRY gene and differentiates ZFX and ZFY gametologues. Skin samples from 628 Dugongs (Dugong Dugon) and 100 Florida manatees (Trichechus manatus latirostris) were analysed and assigned as male or female based on molecular sex. These individuals were also assigned a sex based on either direct observation of the genitalia and/or the association of the individual with a calf. Individuals of both species showed 93 to 96% congruence between visual and molecular sexing. For the remaining 4 to 7%, the discrepancies could be explained by human error. To mitigate this error rate, we recommend using both of these robust techniques, with routine inclusion of sex primers into microsatellite panels employed for identity, along with trained field observers and stringent sample handling.
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a pcr assay for gender assignment in Dugong Dugong Dugon and west indian manatee trichechus manatus
Molecular Ecology Resources, 2008Co-Authors: M Mchale, Damien Broderick, Jennifer R. Ovenden, Janet M. LanyonAbstract:Gender assignment for some aquatic mammals in the field is difficult. Molecular sexing from tissue biopsies is possible as males are heterogametic. Here we describe a multiplex PCR assay that amplifies the male specific SRY gene and differentiates ZFX and ZFY gametologues in two sirenian species, Dugong (Dugong Dugon) and West Indian manatee (Trichechus manatus). The assay was validated with animals of known gender and proved accurate and robust to experimental failure.
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Characterization of 26 new microsatellite loci in the Dugong (Dugong Dugon)
Molecular Ecology Notes, 2007Co-Authors: Damien Broderick, Jennifer R. Ovenden, Rob W. Slade, Janet M. LanyonAbstract:Twenty-six microsatellite loci have been isolated from a Dugong ( Dugong Dugon ). The average heterozygosity was 0.52 with two to 10 alleles per locus surveyed from 50 individuals. The markers are suitable for genetic mark–recapture ( P ID = 5 × 10 –16 ) in Dugongs and they could also be used to quantify physical tag loss, estimate relatedness, assign paternity, elucidate population structure and identify migrants. The loci also amplified in Florida manatees (22/26) and Asian elephants (6/26).
Jennifer R. Ovenden - One of the best experts on this subject based on the ideXlab platform.
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Fine scale population structure of Dugongs (Dugong Dugon) implies low gene flow along the southern Queensland coastline
Conservation Genetics, 2014Co-Authors: Jennifer M. Seddon, Damien Broderick, Jennifer R. Ovenden, Helen L. Sneath, Christine L. Dudgeon, Janet M. LanyonAbstract: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_ST ranged from 0.005 to 0.040 and Jost’s D_EST 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_ST 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.
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characterization of highly informative cross species microsatellite panels for the australian Dugong Dugong Dugon and florida manatee trichechus manatus latirostris including five novel primers
Molecular Ecology Resources, 2010Co-Authors: Margaret Kellogg Hunter, Kimberly Pause Tucker, Damien Broderick, Peter M Mcguire, Robert K Bonde, Jennifer R. Ovenden, Janet M. LanyonAbstract:The Australian Dugong (Dugong Dugon) and Florida manatee (Trichechus manatus latirostris) are threatened species of aquatic mammals in the order Sirenia. Sirenian conservation and management actions would benefit from a more complete understanding of genetic diversity and population structure. Generally, species-specific microsatellite markers are employed in conservation genetic studies; however, robust markers can be difficult and costly to isolate. To increase the number of available markers, Dugong and manatee microsatellite primers were evaluated for cross-species amplification. Furthermore, one manatee and four Dugong novel primers are reported. After polymerase chain reaction optimization, 23 (92%) manatee primers successfully amplified Dugong DNA, of which 11 (48%) were polymorphic. Of the 32 Dugong primers tested, 27 (84%) yielded product in the manatee, of which 17 (63%) were polymorphic. Dugong and manatee primers were compared and the most informative markers were selected to create robust and informative marker-panels for each species. These cross-species microsatellite marker-panels can be employed to assess other sirenian populations and can provide beneficial information for the protection and management of these unique mammals.
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sexing sirenians validation of visual and molecular sex determination in both wild Dugongs Dugong Dugon and florida manatees trichechus manatus latirostris
Aquatic Mammals, 2009Co-Authors: Janet M. Lanyon, Damien Broderick, Jennifer R. Ovenden, Helen L. Sneath, Robert K BondeAbstract:Sexing wild marine mammals that show little to no sexual dimorphism is challenging. For sirenians that are difficult to catch or approach closely, molecular sexing from tissue biopsies offers an alternative method to visual discrimination. This paper reports the results of a field study to validate the use of two sexing methods: (1) visual discrimination of sex vs (2) molecular sexing based on a multiplex PCR assay which amplifies the male-specific SRY gene and differentiates ZFX and ZFY gametologues. Skin samples from 628 Dugongs (Dugong Dugon) and 100 Florida manatees (Trichechus manatus latirostris) were analysed and assigned as male or female based on molecular sex. These individuals were also assigned a sex based on either direct observation of the genitalia and/or the association of the individual with a calf. Individuals of both species showed 93 to 96% congruence between visual and molecular sexing. For the remaining 4 to 7%, the discrepancies could be explained by human error. To mitigate this error rate, we recommend using both of these robust techniques, with routine inclusion of sex primers into microsatellite panels employed for identity, along with trained field observers and stringent sample handling.
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a pcr assay for gender assignment in Dugong Dugong Dugon and west indian manatee trichechus manatus
Molecular Ecology Resources, 2008Co-Authors: M Mchale, Damien Broderick, Jennifer R. Ovenden, Janet M. LanyonAbstract:Gender assignment for some aquatic mammals in the field is difficult. Molecular sexing from tissue biopsies is possible as males are heterogametic. Here we describe a multiplex PCR assay that amplifies the male specific SRY gene and differentiates ZFX and ZFY gametologues in two sirenian species, Dugong (Dugong Dugon) and West Indian manatee (Trichechus manatus). The assay was validated with animals of known gender and proved accurate and robust to experimental failure.
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Characterization of 26 new microsatellite loci in the Dugong (Dugong Dugon)
Molecular Ecology Notes, 2007Co-Authors: Damien Broderick, Jennifer R. Ovenden, Rob W. Slade, Janet M. LanyonAbstract:Twenty-six microsatellite loci have been isolated from a Dugong ( Dugong Dugon ). The average heterozygosity was 0.52 with two to 10 alleles per locus surveyed from 50 individuals. The markers are suitable for genetic mark–recapture ( P ID = 5 × 10 –16 ) in Dugongs and they could also be used to quantify physical tag loss, estimate relatedness, assign paternity, elucidate population structure and identify migrants. The loci also amplified in Florida manatees (22/26) and Asian elephants (6/26).
Robert K Bonde - One of the best experts on this subject based on the ideXlab platform.
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characterization of highly informative cross species microsatellite panels for the australian Dugong Dugong Dugon and florida manatee trichechus manatus latirostris including five novel primers
Molecular Ecology Resources, 2010Co-Authors: Margaret Kellogg Hunter, Kimberly Pause Tucker, Damien Broderick, Peter M Mcguire, Robert K Bonde, Jennifer R. Ovenden, Janet M. LanyonAbstract:The Australian Dugong (Dugong Dugon) and Florida manatee (Trichechus manatus latirostris) are threatened species of aquatic mammals in the order Sirenia. Sirenian conservation and management actions would benefit from a more complete understanding of genetic diversity and population structure. Generally, species-specific microsatellite markers are employed in conservation genetic studies; however, robust markers can be difficult and costly to isolate. To increase the number of available markers, Dugong and manatee microsatellite primers were evaluated for cross-species amplification. Furthermore, one manatee and four Dugong novel primers are reported. After polymerase chain reaction optimization, 23 (92%) manatee primers successfully amplified Dugong DNA, of which 11 (48%) were polymorphic. Of the 32 Dugong primers tested, 27 (84%) yielded product in the manatee, of which 17 (63%) were polymorphic. Dugong and manatee primers were compared and the most informative markers were selected to create robust and informative marker-panels for each species. These cross-species microsatellite marker-panels can be employed to assess other sirenian populations and can provide beneficial information for the protection and management of these unique mammals.
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physiological response of wild Dugongs Dugong Dugon to out of water sampling for health assessment
Aquatic Mammals, 2010Co-Authors: Janet M. Lanyon, Trevor Long, Helen L. Sneath, Robert K BondeAbstract: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.
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sexing sirenians validation of visual and molecular sex determination in both wild Dugongs Dugong Dugon and florida manatees trichechus manatus latirostris
Aquatic Mammals, 2009Co-Authors: Janet M. Lanyon, Damien Broderick, Jennifer R. Ovenden, Helen L. Sneath, Robert K BondeAbstract:Sexing wild marine mammals that show little to no sexual dimorphism is challenging. For sirenians that are difficult to catch or approach closely, molecular sexing from tissue biopsies offers an alternative method to visual discrimination. This paper reports the results of a field study to validate the use of two sexing methods: (1) visual discrimination of sex vs (2) molecular sexing based on a multiplex PCR assay which amplifies the male-specific SRY gene and differentiates ZFX and ZFY gametologues. Skin samples from 628 Dugongs (Dugong Dugon) and 100 Florida manatees (Trichechus manatus latirostris) were analysed and assigned as male or female based on molecular sex. These individuals were also assigned a sex based on either direct observation of the genitalia and/or the association of the individual with a calf. Individuals of both species showed 93 to 96% congruence between visual and molecular sexing. For the remaining 4 to 7%, the discrepancies could be explained by human error. To mitigate this error rate, we recommend using both of these robust techniques, with routine inclusion of sex primers into microsatellite panels employed for identity, along with trained field observers and stringent sample handling.
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echeneid sirenian associations with information on sharksucker diet
Journal of Fish Biology, 2003Co-Authors: Ernest H. Williams, Robert K Bonde, A. Preen, Antonio A Mignuccigiannoni, Lucy Bunkleywilliams, Caryn Selfsullivan, V.g. CockcroftAbstract:Association of the sharksucker Echeneis naucrates and whitefin sharksucker E. neucratoides with the West Indian manatee Trichechus manatus and the Dugong Dugong Dugon is presented and discussed. Alimentary tract-content analysis and field observations suggest that coprophagy (feeding on host faecal material) may be the primary food source for echeneids associated with sirenian hosts.
Helene Marsh - One of the best experts on this subject based on the ideXlab platform.
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Dugong (Dugong Dugon) movements and habitat use in a coral reef lagoonal ecosystem
Endangered Species Research, 2020Co-Authors: Christophe Cleguer, Claire Garrigue, Helene MarshAbstract: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.
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the socio cultural benefits and costs of the traditional hunting of Dugongs Dugong Dugon and green turtles chelonia mydas in torres strait australia
Oryx, 2017Co-Authors: Aurelie Delisle, Milena Kiatkoski Kim, Natalie Stoeckl, Felecia Watkin Lui, Helene MarshAbstract:Signatory states of the Convention on Biological Diversity must ‘protect and encourage the customary use of biological resources in accordance with traditional cultural practices that are compatible with conservation or sustainable use requirements’. Thus the management of traditional hunting of wildlife must balance the sustainability of target species with the benefits of hunting to traditional communities. Conservation policies usually define the values associated with wild meats in terms of income and nutrition, neglecting a wide range of social and cultural values that are important to traditional hunting communities. We elicited the community-defined benefits and costs associated with the traditional hunting of Dugongs Dugong Dugon and green turtles Chelonia mydas from communities on two islands in Torres Strait, Australia. We then used cognitive mapping and multidimensional scaling to identify separable groups of benefits (cultural services, provisioning services, and individual benefits) and demonstrate that traditional owners consider the cultural services associated with traditional hunting to be significantly more important than the provisioning services. Understanding these cultural values can inform management actions in accordance with the Convention on Biological Diversity. If communities are unable to hunt, important cultural benefits are foregone. Based on our results, we question the appropriateness of conservation actions focused on prohibiting hunting and providing monetary compensation for the loss of provisioning services only.
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using parallel regional and local scale initiatives to inform conservation management of rare wildlife a case study of the Dugong Dugong Dugon in sabah malaysia
Endangered Species Research, 2010Co-Authors: Leela Rajamani, Helene MarshAbstract:Obtaining the information needed to inform management strategies for rare wildlife species at appropriate scales is costly and logistically demanding. Using coastal aerial surveys we obtained qualitative information on the distribution and abundance of the Dugong Dugong Dugon at the geopolitical scale of the state of Sabah in east Malaysia. At a local scale, interview surveys and a monitoring program were carried out at 2 sites: Mantanani Island and Banggi Island. A total of 53 Dugongs were observed from the air, concentrated around Labuan Island — Brunei Bay and San- dakan Bay. The interview reports and monitoring program indicated that the residents of Mantanani Island and Banggi Island had local knowledge of the distribution and abundance of Dugongs and, thus, an ability to participate in monitoring at that scale. Dugong populations in Sabah are small and clumped, and urgently require management intervention at local scales in the regionally important habitats identified by the aerial surveys. This combination of regional- and local-scale initiatives has a more generic application in the monitoring of other rare species of wildlife.
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Dugong: Dugong Dugon
Encyclopedia of Marine Mammals, 2009Co-Authors: Helene MarshAbstract:Summary The Dugong is a sirenian. It differs from manatees in that males have tusks and in that the tail is triangular. Dugongs live in nearshore environments of the Indian and western Pacific Ocean.
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movement heterogeneity of Dugongs Dugong Dugon muller over large spatial scales
Journal of Experimental Marine Biology and Ecology, 2006Co-Authors: James K Sheppard, Helene Marsh, Ivan R Lawler, Anthony Preen, Scott D Whiting, R E JonesAbstract:Seventy Dugongs were fitted with satellite PTTs and/or GPS transmitters in sub-tropical and tropical waters of Queensland and the Northern Territory, Australia. Twenty-eight of the 70 Dugongs were also fitted with time-depth recorders. The Dugongs were tracked for periods ranging from 15 to 551 days and exhibited a large range of individualistic movement behaviours; 26 individuals were relatively sedentary (moving 15 km) of up to 560 km from their capture sites. Male and female animals, including cows with calves, exhibited large-scale movements (LSM; > 15 km). Body length of travelling Dugongs ranged from 1.9 to 3 m. At least some of the movements were return movements to the capture location, suggesting that such movements were ranging rather than dispersal movements. LSMs included macro-scale regional movements (> 100 km) and meso-scale inter-patch local movements (15 to 100 km), with a mean ± S.E. travel time of 179.8 ± 29.0 h. The mean ± S.E. meso-scale movement distance per individual was 49.7 ± 3.3 km (N = 28 individuals that made movements of 15–100 km), with a mean ± S.E. travel time of 52.3 ± 7.1 h. LSMs were rapid and apparently directed (mean ± S.E. travel speeds for GPS tagged animals; meso-scale movements = 1.3 ± 0.11 km/h, min = 0.3, max = 3.0; macro-scale movements = 1.6 ± 0.16 km/h, min = 0.8, max = 1.3). Tracked Dugongs rarely travelled far from the coast (mean ± S.E. max distance = 12.8 ± 1.3 km). Dive profiles from the time-depth recorders suggest that Dugongs make repeated deep dives while travelling rather than remaining at the surface, increasing their likelihood of capture in bottom set gill nets. Some animals caught in the high latitude limits of the Dugongs' range on the Australian east coast in winter apparently undertook long distance movements in response to low water temperatures, similar to migrational movements by Florida manatees. Our findings that Dugongs frequently undertake macro-scale movements have implications for management at a range of scales, and strengthen the aerial survey and genetic evidence for management and monitoring at ecological scales that cross jurisdictions.
