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Ding Wang - One of the best experts on this subject based on the ideXlab platform.
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a case of epimeletic behavior and associated acoustic records of indo pacific humpback dolphins Sousa Chinensis
Journal of Mammalogy, 2018Co-Authors: Ding Wang, Shianglin Huang, Zhaolong Cheng, Matthew K Pine, Kexiong WangAbstract:Several cetacean species have demonstrated epimeletic behavior that relies on the tight social bonds between conspecifics. These behaviors and the corresponding vocalizations were recorded during a rare encounter with a group of Indo-Pacific humpback dolphins (Sousa Chinensis) that included a presumed mother and deceased calf, in Sanniang Bay, China. The observed dolphins were divided into 2 apparent groups: 1) a central group with the presumed mother and her deceased calf, along with 1 to 6 other individuals swimming in synchrony with the presumed mother; and 2) a following group of several individuals, dispersed over varying distances from approximately 20 to > 300 m, that swam in the same direction as the central group. The mother was seen mostly supporting the calf's body using her back, anterior to the dorsal fin and posterior to the melon, while the other members of the central group exhibited standing-by behaviors (i.e., remaining close to the deceased calf but not providing aid). Whistles in this context were of a longer duration and a higher complexity in the frequency modulation compared to social contexts. Several whistle types were also repeated frequently. This paper provides a detailed description of epimeletic behavior and the whistles possibly associated with that behavior in an endangered population of Indo-Pacific humpback dolphins.
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distribution and habitat characteristics of the indo pacific humpback dolphin Sousa Chinensis in the northern beibu gulf china
Aquatic Mammals, 2017Co-Authors: Thomas Jefferson, Ding Wang, Mingli Lin, Zhaolong Cheng, Chongwei Peng, Yongyan Liao, Hu Huang, Mingming Liu, Jingxu Zhang, Shianglin HuangAbstract:Studies on the distribution and habitat characteristics of the Indo-Pacific humpback dolphin (Sousa Chinensis) indicate a general preference toward estuarine environments. However, quantitative connections between this preference and estuarine characteristics are seldom investigated. Distribution of the humpback dolphin in the northern Beibu Gulf, China, was evaluated through systematically designed surveys and was compared to oceanographic characteristics from on-board measured and remotely sensed variables. The humpback dolphins' core distribution zone, measured by the 50% kernel density estimate (50% KDE), was confined to the Dafengjiang River Estuary in a 50.23 km(2) area, with a steep-edged underwater sand bar below and locally high chlorophyll-a concentration. The surface salinity distribution showed an eco-cline environment in which riverine runoff mixes with sea water in the 50% KDE. We found significant relationships between distribution probability and two oceanographic variables: (1) water depth and (2) chlorophyll-a concentration. This associates the distribution preference of humpback dolphins with regional productivity and biodiversity peaks that may facilitate prey aggregation. As humpback dolphins inhabit comparable environments in other locations throughout their range, the oceanographic features of the 50% KDE may help to provide proxies to identify other key habitats over a broader spatial scale.
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fine scale habitat use in indo pacific humpback dolphins Sousa Chinensis may be more influenced by fish rather than vessels in the pearl river estuary china
Marine Mammal Science, 2017Co-Authors: Matthew K Pine, Kexiong Wang, Ding WangAbstract:Shifts in habitat use and distribution patterns in dolphins are often concerns that can result from habitat degradation. We investigated how potential changes to a habitat from human activity may alter dolphin distributions within Lingding Bay in the Pearl River Estuary, China, by studying the relationship between fish choruses, vessel presence and Indo-Pacific humpback dolphin (Sousa Chinensis) detection rates. Analyses revealed temporal and spatial variation within fish choruses, vessel presence and dolphin detection rates. After accounting for any temporal autocorrelation, correlations between fish choruses and dolphin detection rates were also found; however, no relationship between fish choruses and vessel presence or dolphin detection rates and vessel presence were observed. Furthermore, fewer dolphins were detected at sites where fish activity was less intense. Thus fish activity, rather than vessels, may be a key factor influencing the distribution of the dolphins within the estuary. These findings emphasize the risk of potential shifts in habitat use for Indo-Pacific humpback dolphins due to detrimental changes to prey availability and dolphin feeding grounds from human activity, such as overfishing and coastal developments, within the estuary. This is a critical conservation issue for this dolphin population that is facing intense anthropogenic pressure.
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first record of the indo pacific humpback dolphins Sousa Chinensis southwest of hainan island china
Marine Biodiversity Records, 2016Co-Authors: Mingli Lin, Luru Xing, Peijun Zhang, Rodolphe E Gozlan, Shianglin Huang, Ding WangAbstract:Populations of Indo-Pacific humpback dolphins (Sousa Chinensis) in China were known to be distributed from the Beibu Gulf near the border with Vietnam to the mouth of the Yangtze River. According to existing studies, the waters around Hainan Island, China, were not considered to be part of the humpback dolphins’ distribution. In 2014, for the first time, we recorded humpback dolphins in waters southwest of Hainan Island. This record expands the known southern distribution range of this dolphin in Chinese waters by more than 300 km.
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likely age related hearing loss presbycusis in a stranded indo pacific humpback dolphin Sousa Chinensis
Advances in Experimental Medicine and Biology, 2016Co-Authors: Ding Wang, Kexiong Wang, Wenzhi Lin, Matthias Hoffmannkuhnt, Nimal Fernando, Elizabeth A Taylor, Jialin ChenAbstract:The hearing of a stranded Indo-Pacific humpback dolphin (Sousa Chinensis) in Zhuhai, China, was measured. The age of this animal was estimated to be similar to 40 years. The animal's hearing was measured using a noninvasive auditory evoked potential (AEP) method. The results showed that the high-frequency hearing cutoff frequency of the studied dolphin was similar to 30-40 kHz lower than that of a conspecific younger individual similar to 13 year old. The lower high-frequency hearing range in the older dolphin was explained as a likely result of age-related hearing loss (presbycusis).
Shianglin Huang - One of the best experts on this subject based on the ideXlab platform.
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dolphin watching tourism and indo pacific humpback dolphins Sousa Chinensis in sanniang bay china impacts and solutions
European Journal of Wildlife Research, 2020Co-Authors: Chongwei Peng, Thomas A. Jefferson, Shianglin Huang, Hu Huang, Mo Chen, Qianhui Zeng, Xianyan WangAbstract:Cetacean-watching tourism has become an economically important recreation industry, but can compromise cetacean viability and hence tourism sustainability. While current management tactics pay much attention on industrialized cetacean-watching tourisms, impacts of tours operated by motorized boats in inshore waters are seldom discussed. This study investigated the spatial and temporal activities of dolphin-watching tours in Sanniang Bay, China, where tours specifically focus on Indo-Pacific humpback dolphins (Sousa Chinensis). The primary boat-dolphin interaction directly overlaps with a core habitat of humpback dolphins. Average tour duration was shorter than 40 min and approximately one third of time was spent on following dolphins. Monthly tour activities were extremely high in February, early May, August, and October that corresponded to Chinese national festivals. An eastward shift of primary interaction site during high-tour-activity months implies a long-term tour impacts on habitat use of humpback dolphins in northern Beibu Gulf. We urge a collaboration and coordination between boat captains, tour managers, maritime administrative, academic teams, and NGOs to systematically collect tour statistics in Sanniang Bay, including daily tour and visitor numbers, encounter duration and locations, and unsustainable maritime activities. As eco-tourisms targeting humpback dolphins and other coastal cetaceans adopting small motorized boats are rapidly growing in southeastern Asia, management guidelines involving codes of conduct, allowable daily trips, and sustainable tourism tactics are urgently needed before the tourism becomes industrialized and economically oriented. Variables and statistics presented in this study can provide a baseline proxy to help design management guidelines to minimize unsustainable impacts on the target animals.
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the microbiomic and environmental analysis of sediments in the indo pacific humpback dolphin Sousa Chinensis habitat in the northern beibu gulf china
Environmental Science and Pollution Research, 2019Co-Authors: Bin Gong, Jingzhen Wang, Shianglin Huang, Chongwei Peng, Hu Huang, Xiangxu Liu, Songying OuyangAbstract:The northern Beibu Gulf is one of the major habitats for the Indo-Pacific humpback dolphin (Sousa Chinensis) in China. In this habitat, the core distribution zone of humpback dolphins was confined to the Sanniang Bay (SNB) and Dafengjiang River Estuary (DRE) areas. In our present research, the sediments of 14 sampling sites across the SNB and DRE waters were collected and further conducted for microbiomic and environmental analysis to explore the ecosystem characteristics of major humpback dolphin habitats in Northern Beibu Gulf. The environmental condition includes ammonia nitrogen (NH4+-N), nitrate nitrogen (NO3--N), dissolved reactive phosphorus (DRP), sulfur content in the form of sulfuric acid (SO42--S), Fe, and heavy metals (including Cu, Zn, Cd, Pb, and As). The composition of the bacterial community was characterized by 16S ribosomal DNA analysis of the V3-V4 regions using the Illumina-based sequencing platform. The environmental characteristic of the nutrient elements and heavy metals indicated that SNB suffered more anthropogenic impact than DRE. The comparably higher concentration of NH4+-N, NO3--N, DRP, Pb, and Cd in the SNB region was detected. The comparably higher nutrients in the SNB may have resulted in higher biomass and lower dissolved oxygen (DO) profile, which was further proved by Landsat thermal image data. The microbiome analysis showed that the DRE region was oligotrophic and SNB reflected an anaerobic environment in the sediments. Environmental factors rather than the spatial distance determined the similarity of bacterial community among different sites. Ecological associations between environmental, oceanographic, and bacterial characteristics were illustrated, which exhibited strong mutual associations. Our findings presented a feasibility that integrates empirical and remote sensing data to distinguish ecological features and evaluate ecosystem healthiness for the humpback dolphin habitats.
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a case of epimeletic behavior and associated acoustic records of indo pacific humpback dolphins Sousa Chinensis
Journal of Mammalogy, 2018Co-Authors: Ding Wang, Shianglin Huang, Zhaolong Cheng, Matthew K Pine, Kexiong WangAbstract:Several cetacean species have demonstrated epimeletic behavior that relies on the tight social bonds between conspecifics. These behaviors and the corresponding vocalizations were recorded during a rare encounter with a group of Indo-Pacific humpback dolphins (Sousa Chinensis) that included a presumed mother and deceased calf, in Sanniang Bay, China. The observed dolphins were divided into 2 apparent groups: 1) a central group with the presumed mother and her deceased calf, along with 1 to 6 other individuals swimming in synchrony with the presumed mother; and 2) a following group of several individuals, dispersed over varying distances from approximately 20 to > 300 m, that swam in the same direction as the central group. The mother was seen mostly supporting the calf's body using her back, anterior to the dorsal fin and posterior to the melon, while the other members of the central group exhibited standing-by behaviors (i.e., remaining close to the deceased calf but not providing aid). Whistles in this context were of a longer duration and a higher complexity in the frequency modulation compared to social contexts. Several whistle types were also repeated frequently. This paper provides a detailed description of epimeletic behavior and the whistles possibly associated with that behavior in an endangered population of Indo-Pacific humpback dolphins.
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long term habitat loss in a lightly disturbed population of the indo pacific humpback dolphin Sousa Chinensis
Aquatic Conservation-marine and Freshwater Ecosystems, 2017Co-Authors: Chongwei Peng, Xianyan Wang, Thomas Jefferson, Yongyan Liao, Hu Huang, Shianglin HuangAbstract:Coastal and estuarine waters are important ecosystems with high primary and secondary productivity, but they are prone to the impacts of habitat loss caused by anthropogenic activities. For species exclusively inhabiting coastal and estuarine waters, such as the Indo-Pacific humpback dolphin, Sousa Chinensis, irreversible habitat loss can have dramatic implications for population viability. A Landsat image database was used to determine the extent of coastal changes along the northern Beibu Gulf, where a large humpback dolphin population is found. The results were compared with the standardized sighting gradient (SPUF) determined from a questionnaire survey of fishermen and likely core habitats identified by application of a global digital elevation model. Both SPUF and likely core habitat results indicated a continuous distribution of the humpback dolphin along the northern Beibu Gulf. Landsat images revealed that 129.6 km2 of coastal waters were permanently lost in the past 40 years, 60 km2 within the likely core habitats. Although this may be considered small, the impact of such habitat loss could be substantial in some local habitats. The humpback dolphin population in the northern Beibu Gulf should be regarded as one management unit, with two or more social subunits. Immediate systematic surveys are needed to fill information gaps on true distribution range and habitat-use patterns. Habitat protection actions for dolphins in the northern Beibu Gulf should include both core and linking habitats, including enacting protected areas in core habitats, mitigating anthropogenic impacts in likely habitats, restoring both coastal waters and surrounding landscape quality, effective treatment of industrial sewage discharge, and comprehensive environmental impact assessments for the planning of coastal development projects.
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distribution and habitat characteristics of the indo pacific humpback dolphin Sousa Chinensis in the northern beibu gulf china
Aquatic Mammals, 2017Co-Authors: Thomas Jefferson, Ding Wang, Mingli Lin, Zhaolong Cheng, Chongwei Peng, Yongyan Liao, Hu Huang, Mingming Liu, Jingxu Zhang, Shianglin HuangAbstract:Studies on the distribution and habitat characteristics of the Indo-Pacific humpback dolphin (Sousa Chinensis) indicate a general preference toward estuarine environments. However, quantitative connections between this preference and estuarine characteristics are seldom investigated. Distribution of the humpback dolphin in the northern Beibu Gulf, China, was evaluated through systematically designed surveys and was compared to oceanographic characteristics from on-board measured and remotely sensed variables. The humpback dolphins' core distribution zone, measured by the 50% kernel density estimate (50% KDE), was confined to the Dafengjiang River Estuary in a 50.23 km(2) area, with a steep-edged underwater sand bar below and locally high chlorophyll-a concentration. The surface salinity distribution showed an eco-cline environment in which riverine runoff mixes with sea water in the 50% KDE. We found significant relationships between distribution probability and two oceanographic variables: (1) water depth and (2) chlorophyll-a concentration. This associates the distribution preference of humpback dolphins with regional productivity and biodiversity peaks that may facilitate prey aggregation. As humpback dolphins inhabit comparable environments in other locations throughout their range, the oceanographic features of the 50% KDE may help to provide proxies to identify other key habitats over a broader spatial scale.
John Y Wang - One of the best experts on this subject based on the ideXlab platform.
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severe mutilation of a critically endangered taiwanese humpback dolphin Sousa Chinensis taiwanensis by fishing gear
Diseases of Aquatic Organisms, 2017Co-Authors: John Y Wang, Claryana AraujowangAbstract:Direct observations of the causes of injuries to cetaceans are rare events. For very small and declining populations, such events may be even less likely to be observed because of the few individuals that remain. A long-term monitoring program using photographic identification of individuals resulted in the documentation of an individual Taiwanese humpback dolphin Sousa Chinensis taiwanensis that survived a harmful interaction with fishing gear. An adult female that was accompanied by a young calf sustained massive damage to several tissue types on her dorsal surface. From the injuries, it is clear that the animal had suffered intense trauma that likely caused pain for several months as the fishing gear sliced through its dorsal hump and fin. Given the incredible mutilation, the animal is likely compromised at some level and probably continues to experience ongoing pain. This case, along with observations of other individuals in this population bearing serious injuries or being entangled in fishing gear, is direct evidence that the impacts of local fisheries on this subspecies are almost certainly unsustainable.
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unsustainable human induced injuries to the critically endangered taiwanese humpback dolphins Sousa Chinensis taiwanensis
Marine Pollution Bulletin, 2017Co-Authors: John Y Wang, Shih Chu Yang, Kimberly N Riehl, Claryana AraujowangAbstract:The Critically Endangered Taiwanese humpback dolphin (Sousa Chinensis taiwanensis) is endemic to inshore and estuarine waters of central western Taiwan. It numbers fewer than 75 individuals, is declining and faces a myriad of human threats. Data from a long-term photo-identification program on these dolphins allowed major injuries to be examined quantitatively. A large proportion (57.7%) of individuals had suffered major human-induced injuries that likely compromised their health, survivorship or reproductive potential and thus, the future of this subspecies. Considering major injuries as "takes", the injury rate (1.13 dolphins/year) for the population was 8-8.5 times higher than its Potential Biological Removal rate. Observations of new injuries and fishing gear entanglements on several dolphins showed that fisheries continue to be the predominant cause of these major injuries. Unless immediate action is taken to reduce harmful fisheries, extinction is imminent for Taiwan's only endemic dolphin.
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social structure in a critically endangered indo pacific humpback dolphin Sousa Chinensis population
Aquatic Conservation-marine and Freshwater Ecosystems, 2016Co-Authors: Sarah Z Dungan, John Y Wang, Shih Chu Yang, Claryana C Araujo, Bradley N WhiteAbstract:Social behaviour can be a vital aspect of population viability when it influences survivorship and reproductive fitness, which is often the case for especially social species, including cetaceans. Understanding this relationship is important in at-risk populations, where knowledge of network structure can provide insight into how they may respond to human impacts. Association patterns in the critically endangered eastern Taiwan Strait (ETS) population of Indo-Pacific humpback dolphins, Sousa Chinensis, were investigated using the seasonally collected (2007–2010) photo-identification data of 74 individuals. Social network structure was characterized by high strength and reach, features that are thought to be atypical for the species. Standardized lagged association rates were best fitted by a two-level model: short-term associations that dissipated in less than a day, and long-term associations projected to persist nearly 10 years. These persisting relationships were primarily among calves and their inferred mothers. The short-term associations, which were probably limiting the network's modularity, seemed to occur among more weakly associated individuals temporarily participating in large mother–calf groups. When associations were defined by proximity (within one body-length), relationships involving calves were characterized by a significantly high clustering coefficient, and some calves had high associations with other calves and more than one adult, making maternal relationships ambiguous. This could be evidence for cooperative calf rearing, which may be important for calf survivorship and initiating dyadic relationships among calves. Given their apparent uniqueness among populations of this species, the association patterns observed among the ETS S. Chinensis, calves and their inferred mothers in particular, could be a response to conditions (small population size, isolation, confined distribution, and anthropogenic stressors) that make long-term cooperative behaviour advantageous. Thus, minimizing human impacts that disrupt social dynamics, such as interactions with fisheries and habitat fragmentation, should help to improve this population's long-term viability. Copyright © 2015 John Wiley & Sons, Ltd.
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biology and conservation of the taiwanese humpback dolphin Sousa Chinensis taiwanensis
Advances in Marine Biology, 2016Co-Authors: John Y Wang, Kimberly N Riehl, Michelle N Klein, Shiva Javdan, Jordan M Hoffman, Sarah Z Dungan, Lauren E Dares, Claryana AraujowangAbstract:The humpback dolphins of the eastern Taiwan Strait were first discovered scientifically in 2002 and since then have received much research attention. We reviewed all information published in peer-reviewed scientific journals on these dolphins and where appropriate and available, peer-reviewed scientific workshop reports and graduate theses were also examined. Recent evidence demonstrated that this population warranted recognition as a subspecies, Sousa Chinensis taiwanensis. It is found in a highly restricted and linear strip of coastal waters along central western Taiwan. Numbering fewer than 80 individuals and declining, five main threats (fisheries interactions, habitat loss and degradation, loss of freshwater to estuaries within their habitat, air and water pollution, and noise) threaten the future existence of this subspecies. These dolphins have cultural and religious importance and boast the highest level of legal protection for wildlife in Taiwan. However, despite enormous efforts by local and international non-governmental groups urging immediate conservation actions, there have been no real government efforts to mitigate any existing threats; instead, some of these threats have worsened. Based on recent studies, we suggest the IUCN Red List status be revised to Critically Endangered CR 2a(ii); D for the subspecies.
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comparison of indo pacific humpback dolphin Sousa Chinensis whistles from two areas of western peninsular malaysia
Journal of the Acoustical Society of America, 2015Co-Authors: Jordan M Hoffman, John Y Wang, Louisa S Ponnampalam, Claryana C Araujo, Sui Hyang Kuit, Samuel K HungAbstract:Differences in the acoustic variables of whistles emitted by Indo-Pacific humpback dolphins (Sousa Chinensis) from two coastal locations along western Peninsular Malaysia were investigated. Duration, frequency, and frequency modulation variables were extracted from and used to characterize recordings of free-ranging humpback dolphins that were made using a broadband towed hydrophone. A total of 960 whistles from Matang Mangroves and 823 whistles from Langkawi Island were used in analyses. The whistles of Malaysian humpback dolphins covered frequencies from 1231 to 27 120 Hz with durations from 0.010–1.575 s. Significant multivariate differences were found in whistles emitted between locations. Significant differences were also found between dolphins of the two locations in their whistle duration, frequency modulation, and all frequency variables except for minimum frequency, which is likely under morphological constraints. The differences in whistles may be related to adaptations to the local acoustic habitat or unique whistles may have developed due to social interactions within each location, or broader scale differences resulting from geographic separation between the locations.
Paul K S Lam - One of the best experts on this subject based on the ideXlab platform.
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total fluorine extractable organic fluorine perfluorooctane sulfonate and other related fluorochemicals in liver of indo pacific humpback dolphins Sousa Chinensis and finless porpoises neophocaena phocaenoides from south china
Environmental Pollution, 2009Co-Authors: Leo W Y Yeung, Nobuyoshi Yamashita, Sachi Taniyasu, Yuichi Miyake, Yuan Wang, Paul K S LamAbstract:The concentrations of 10 PFCs (perfluorinated compounds: PFOS, PFHxS, PFOSA, N-EtFOSA, PFDoDA, PFUnDA, PFDA, PFNA, PFOA, and PFHpA) were measured in liver samples of Indo-Pacific humpback dolphins (Sousa Chinensis) (n=10) and finless porpoises (Neophocaena phocaenoides) (n=10) stranded in Hong Kong between 2003 and 2007. PFOS was the dominant PFC in the tissues at concentrations ranging at 26-693 ng/g ww in dolphins and 51.3-262 ng/g ww in porpoises. A newly developed combustion ion chromatography for fluorine was applied to measure total fluorine (TF) and extractable organic fluorine (EOF) in these liver samples to understand PFC contamination using the concept of mass balance analysis. Comparisons between the amounts of known PFCs and EOF in the livers showed that a large proportion (approximately 70%) of the organic fluorine in both species is of unknown origin. These investigations are critical for a comprehensive assessment of the risks of these compounds to humans and other receptors.
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a preliminary risk assessment of trace elements accumulated in fish to the indo pacific humpback dolphin Sousa Chinensis in the northwestern waters of hong kong
Chemosphere, 2004Co-Authors: Craig L H Hung, Des Connell, C N Fung, Michael H W Lam, S Nicholson, Bruce J Richardson, Paul K S LamAbstract:In order to assess the potential risks associated with consumption of contaminated prey items to the Indo-Pacific Humpback dolphin (Sousa Chinensis), fish species (Collichthys lucida, Pseudosciaena crocea, Johnius sp., Thryssa sp., Mugil sp. and Trichiurus sp.) representing the main food items of the dolphin were collected from the Northwestern waters of Hong Kong, including the Sha Chau and Lung Kwu Chau Marine Park, which form the main habitat of the dolphin in Hong Kong. Within these waters, there are several potential sources of pollution including significant inputs from the Pearl River catchment, several major sewage outfalls and a series of mud pits that receive contaminated dredged sediments. Concentrations of thirteen trace elements (Ag, As, Cd, Co, Cr, Cs, Cu, Hg, Mn, Ni, Se, V, and Zn) in the fish tissue were analyzed by inductively coupled plasma mass spectrometer (ICP-MS). An assessment of the risks of adverse effects on the dolphin due to consumption of tainted fish was undertaken using two toxic reference benchmarks, namely the reference dose (RfD) and toxicity reference value (TRV). The risk quotient (RQ) calculated for each element showed that the risks from consumption of fish were generally low and within safe limits. The risks associated with arsenic, cadmium and mercury were, however, elevated. The highest calculated RQ was associated with total arsenic; however, the majority of arsenic in marine organisms tends to be in the non-toxic organic form, and the actual risk to the dolphin due to this metalloid is likely to be lower.
Nobuyoshi Yamashita - One of the best experts on this subject based on the ideXlab platform.
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total fluorine extractable organic fluorine perfluorooctane sulfonate and other related fluorochemicals in liver of indo pacific humpback dolphins Sousa Chinensis and finless porpoises neophocaena phocaenoides from south china
Environmental Pollution, 2009Co-Authors: Leo W Y Yeung, Sachi Taniyasu, Yuichi Miyake, Yuan Wang, Nobuyoshi YamashitaAbstract:Abstract The concentrations of 10 PFCs (perfluorinated compounds: PFOS, PFHxS, PFOSA, N -EtFOSA, PFDoDA, PFUnDA, PFDA, PFNA, PFOA, and PFHpA) were measured in liver samples of Indo-Pacific humpback dolphins ( Sousa Chinensis ) ( n = 10) and finless porpoises ( Neophocaena phocaenoides ) ( n = 10) stranded in Hong Kong between 2003 and 2007. PFOS was the dominant PFC in the tissues at concentrations ranging at 26–693 ng/g ww in dolphins and 51.3–262 ng/g ww in porpoises. A newly developed combustion ion chromatography for fluorine was applied to measure total fluorine (TF) and extractable organic fluorine (EOF) in these liver samples to understand PFC contamination using the concept of mass balance analysis. Comparisons between the amounts of known PFCs and EOF in the livers showed that a large proportion (∼70%) of the organic fluorine in both species is of unknown origin. These investigations are critical for a comprehensive assessment of the risks of these compounds to humans and other receptors.
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total fluorine extractable organic fluorine perfluorooctane sulfonate and other related fluorochemicals in liver of indo pacific humpback dolphins Sousa Chinensis and finless porpoises neophocaena phocaenoides from south china
Environmental Pollution, 2009Co-Authors: Leo W Y Yeung, Nobuyoshi Yamashita, Sachi Taniyasu, Yuichi Miyake, Yuan Wang, Paul K S LamAbstract:The concentrations of 10 PFCs (perfluorinated compounds: PFOS, PFHxS, PFOSA, N-EtFOSA, PFDoDA, PFUnDA, PFDA, PFNA, PFOA, and PFHpA) were measured in liver samples of Indo-Pacific humpback dolphins (Sousa Chinensis) (n=10) and finless porpoises (Neophocaena phocaenoides) (n=10) stranded in Hong Kong between 2003 and 2007. PFOS was the dominant PFC in the tissues at concentrations ranging at 26-693 ng/g ww in dolphins and 51.3-262 ng/g ww in porpoises. A newly developed combustion ion chromatography for fluorine was applied to measure total fluorine (TF) and extractable organic fluorine (EOF) in these liver samples to understand PFC contamination using the concept of mass balance analysis. Comparisons between the amounts of known PFCs and EOF in the livers showed that a large proportion (approximately 70%) of the organic fluorine in both species is of unknown origin. These investigations are critical for a comprehensive assessment of the risks of these compounds to humans and other receptors.
