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Using an Aural Classifier to Discriminate Cetacean VocalizationsBinder, Carolyn 26 March 2012 (has links)
To positively identify marine mammals using passive acoustics, large volumes of data are often collected that need to be processed by a trained analyst. To reduce acoustic analyst workload, an automatic detector can be implemented that produces many detections, which feed into an automatic classifier to significantly reduce the number of false detections. This requires the development of a robust classifier capable of performing inter-species classification as well as discriminating cetacean vocalizations from anthropogenic noise sources. A prototype aural classifier was developed at Defence Research and Development Canada that uses perceptual signal features which model the features employed by the human auditory system. The dataset included anthropogenic passive transients and vocalizations from five cetacean species: bowhead, humpback, North Atlantic right, minke and sperm whales. Discriminant analysis was implemented to replace principal component analysis; the projection obtained using discriminant analysis improved between-species discrimination during multiclass cetacean classification, compared to principal component analysis. The aural classifier was able to successfully identify the vocalizing cetacean species. The area under the receiver operating characteristic curve (AUC) is used to quantify the two-class classifier performance and the M-measure is used when there are three or more classes; the maximum possible value of both AUC and M is 1.00 – which is indicative of an ideal classifier model. Accurate classification results were obtained for multiclass classification of all species in the dataset (M = 0.99), and the challenging bowhead/ humpback (AUC = 0.97) and sperm whale click/anthropogenic transient (AUC = 1.00) two-class classifications.
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Large and grey : whales, elephants, and international law and politics.January 2008 (has links)
This thesis is an investigation into, and a gathering of evidence on, the various ways in which two iconic species, whales and elephants, and the two conventions which govern their management, the 1946 International Convention for the Regulation of Whaling (ICRW) and the 1973 Convention on International Trade in Endangered Species (CITES), are linked in international law and politics. After explaining the nature of international conventions governing wildlife species generally, the respective histories of the two conventions are considered: first, that of the ICRW is considered, together with its strengths, weaknesses and current position; after which a similar assessment is made of CITES. The history of linkage between the two is considered, including attempts made to use the one to undercut the other. Various aspects of the protection, use and management of the two species are then canvassed; and it is shown how important political actors hold apparently mutually exclusive views. Throughout, the position of South Africa is particularly considered. The importance of protecting biological diversity is then considered, together with the potential harmonising role of the 1989 Convention on Biological Diversity (CBD), and the political stances of various countries, together with ongoing analysis of efforts to effect change. The natures of whales and elephants as symbols, and as special animals, are then considered. In conclusion, it is explained that both treaties could work if the political drive was present - but that this is currently absent, and the environment is suffering whilst politicians argue over the best courses to follow to protect natural resources. It is suggested that the reason that the arguments in respect of whales and elephants, the ICRW and CITES, are so bitter is because so much is at stake - for the fight on this battleground is not simply about the particular species, but the course the world as a whole should follow in all of its use of natural resources. Understanding the links between species and between treaties helps us to understand alternative possible courses. By exploring one such set of links that has not previously been analysed, the research presented in this thesis is intended to make a contribution to that understanding (both internationally and within South Africa). / Thesis (LL.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.
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Biogeography and conservation of the pinnipeds (Carnivora: Mammalia)Higdon, Jeffrey Wayde 14 January 2011 (has links)
This thesis examines the biogeography of world pinnipeds, a unique group of marine mammals that have adapted to marine foraging while maintaining terrestrial (land or ice) habitat links. Comparative analyses of species range sizes controlled for phylogenetic relationships using a multi-gene supertree with divergence dates estimated using fossil calibrations. Adaptations to aquatic mating and especially sea ice parturition have influenced range size distribution, and ranges are larger than those of terrestrially mating and/or pupping species. Small range size is endangering for many taxa, and most at risk pinnipeds are terrestrial species with small ranges. Ancestral state reconstructions suggest that pinnipeds had a long association with sea ice, an adaptation that would have allowed early seals to expand into novel habitats and increase their distribution. Range sizes exhibit a strong Rapoport effect (positive relationship between range size and latitude) at the global scale, even after controlling for phylogeny and body size allometry. A latitudinal gradient in species diversity cannot explain the Rapoport effect for global pinniped ranges, as diversity is highest at mid-latitudes in both hemispheres. These regions are characterized by marginal ice zones and variable climates, supporting a mix of pagophilic and temperate species. The climatic variability hypothesis also did not explain the Rapoport effect. Variability is bimodal, and annual sea surface temperature (SST) variability does explain diversity patterns. Range size has a significant negative relationship with annual mean SST, and the largest ranges are found in areas with low mean SST. Temperature responses are possibly related to thermoregulation, sea ice availability, and ecological relationships with other large marine predators. These results agree with other studies and suggest that ocean temperature, and not productivity, drives marine species richness patterns. Future research needs include studies of physiological tolerances, interactions with sharks as predators and competitors, and the role of climate and sea ice in speciation and evolution. A better understanding of distribution and diversity patterns, and the role of the environment in shaping these patterns, will improve conservation efforts, and studies on the role of SST and sea ice are particularly important given current warming trends and declines in ice extent.
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Biogeography and conservation of the pinnipeds (Carnivora: Mammalia)Higdon, Jeffrey Wayde 14 January 2011 (has links)
This thesis examines the biogeography of world pinnipeds, a unique group of marine mammals that have adapted to marine foraging while maintaining terrestrial (land or ice) habitat links. Comparative analyses of species range sizes controlled for phylogenetic relationships using a multi-gene supertree with divergence dates estimated using fossil calibrations. Adaptations to aquatic mating and especially sea ice parturition have influenced range size distribution, and ranges are larger than those of terrestrially mating and/or pupping species. Small range size is endangering for many taxa, and most at risk pinnipeds are terrestrial species with small ranges. Ancestral state reconstructions suggest that pinnipeds had a long association with sea ice, an adaptation that would have allowed early seals to expand into novel habitats and increase their distribution. Range sizes exhibit a strong Rapoport effect (positive relationship between range size and latitude) at the global scale, even after controlling for phylogeny and body size allometry. A latitudinal gradient in species diversity cannot explain the Rapoport effect for global pinniped ranges, as diversity is highest at mid-latitudes in both hemispheres. These regions are characterized by marginal ice zones and variable climates, supporting a mix of pagophilic and temperate species. The climatic variability hypothesis also did not explain the Rapoport effect. Variability is bimodal, and annual sea surface temperature (SST) variability does explain diversity patterns. Range size has a significant negative relationship with annual mean SST, and the largest ranges are found in areas with low mean SST. Temperature responses are possibly related to thermoregulation, sea ice availability, and ecological relationships with other large marine predators. These results agree with other studies and suggest that ocean temperature, and not productivity, drives marine species richness patterns. Future research needs include studies of physiological tolerances, interactions with sharks as predators and competitors, and the role of climate and sea ice in speciation and evolution. A better understanding of distribution and diversity patterns, and the role of the environment in shaping these patterns, will improve conservation efforts, and studies on the role of SST and sea ice are particularly important given current warming trends and declines in ice extent.
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Biomagnification and fate of persistent organic pollutants (POPs) in marine mammal food webs in the Northeastern Pacific OceanCullon, Donna Lynn 31 August 2010 (has links)
Elevated polychlorinated biphenyl (PCB) concentrations have been detected in marine mammals inhabiting the Strait of Georgia, British Columbia (Canada) and Puget Sound, Washington State (USA). This raises concerns about adverse health effects and underscores the importance of documenting source, transport, and fate of contaminants. This marine mammal-oriented study- (1) examines dietary exposure to complex mixtures of persistent organic pollutants (POPs); (2) characterizes POP accumulations using congener-specific contaminant analyses, stable isotope ratios, and multivariate statistical methods; and (3) explores some of the influencing factors for POP bioaccumulation in marine mammals.
A first application of a food basket approach to assessing real-world dietary exposure to mixtures of chemicals in marine mammals has revealed Puget Sound as a regional “hotspot” for PCB contamination. The consistency between PCB concentrations in Puget Sound and the Strait of Georgia harbour seals (Phoca vitulina) and their food baskets validates the use of this method as a basis for exploring dietary exposure, metabolism, biomagnification, and health risks in marine mammals. Concentration rankings of POPs and estimated daily intakes based on our food baskets suggests that both legacy (e.g., PCB, dichlorodiphenyltrichloroethane [DDT]) and new (polybrominated diphenyl ethers [PBDEs]) POPs may pose potential health risks to seals.
Accumulations of PCBs in the Strait of Georgia seal food web demonstrate the bioaccumulative nature and persistence of PCBs. Correlations of PCB concentrations with physicochemical properties and trophic level revealed the important role that metabolism plays in biomagnification in seals, alongside trophic level and log Kow. We estimate a PCB load of 77 kg within the Strait of Georgia biomass, with the largest proportion (36 %) detected in marine mammals.
Dietary exposure of POPs to resident killer whales (Orcinus orca) was assessed by measuring POPs in four stocks of chinook salmon (Oncorhynchus tshawytscha), their primary prey. Differences in POP concentrations between chinook smolts and returning adults suggest that the majority of POPs are acquired at sea during the major growth period in their life cycle. Higher POP concentrations and low lipid content were observed among the more southerly stocks suggesting a migration-associated metabolism and loss of lighter congeners, thereby exposing southern residents to more highly contaminated chinook salmon. Consumption on a lipid-weight basis, (higher consumption on a wet weight basis), as well as consuming prey from a more contaminated region, likely increases killer whale exposure to POPs, offering an explanation for higher contaminant burdens in southern residents.
While previous research has examined species inhabiting different trophic levels or food chains in other regions, this study has provided an assessment of POP dietary exposure, biomagnification, and influencing factors on trophic accumulations in a North-eastern Pacific marine mammal food web. These results have provided further insight into the influence of such factors as age, sex, lipid content, diet, migration-related metabolism, physicochemical properties (degree of chlorination, log Kow), and chemical structure on POP accumulation in marine mammals. We have identified the largely unregulated PBDEs as posing potential health risks to marine mammals and offered a means to update existing tissue residue guidelines for the protection of wildlife.
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Bioaccumulative contaminants in marine mammals: uptake and effectsNoel, Marie 12 April 2013 (has links)
This thesis provides insights into the transport and fate of contaminants of concern (polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and mercury (Hg)), as well as results on the impacts of these compounds on marine mammal health.
Atmospheric transport is known to be a significant pathway for the delivery of contaminants to remote food webs. Air and rain samples were collected from one remote site on the west coast of Vancouver Island, British Columbia (BC), Canada, and from one near-urban site in the Strait of Georgia, BC. While global atmospheric dispersion was observed for the legacy PCBs, 40% of PBDEs detected in BC air appeared to be originating from trans-Pacific transport. It was estimated that 3kg of PCBs and 17kg of PBDEs were deposited every year in the Strait of Georgia.
Once deposited, PCBs, PBDEs and Hg biomagnify up the food chain. Harbour seals are non-migratory and can be used to provide signals of local contaminant sources. They have been extensively used as indicators of PCB and PBDE food web contamination in the BC coastal environment. The collection of over 200 harbour seal fur samples from various locations around Vancouver Island, BC and Puget Sound, WA, USA helped us pinpoint three sites where Hg levels were significantly higher than our reference site, Bella Bella (Queen Charlotte Strait, Port Renfrew and central Puget Sound). A combination of anthropogenic sources and marine food web processes appeared to influence the delivery of methylmercury (MeHg) to the top of this coastal marine food chain. Our results also suggested that these Hg levels (1.6-46.9 µg/g) could be a concern for the health of these harbour seals.
Genomic techniques were used to generate insights into the implications of contaminant exposure on the health of marine mammals inhabiting industrialized regions (harbour seals from the Northeastern Pacific and Northwestern Atlantic) and remote, supposedly pristine, environment (Arctic beluga whales). In harbour seal blubber, there were positive correlations between the mRNA levels of several genes, including estrogen receptor alpha (Esr1), thyroid hormone receptor alpha (Thra), and glucocorticoid receptor (Nr3c1), and PCB levels. In beluga blubber, aryl hydrocarbon receptor (Ahr) and cytochrome P450 (Cyp1a1) mRNA levels increased with PCBs, consistent with their role in toxicity.While PCB-related toxic responses were observed in both species, additional factors appeared to be affecting the expression of important genes in beluga. Our results suggested that a shift in beluga diet during periods of low sea ice extent, as evidenced by changes in δ13C isotope ratios, had a significant impact on mRNA levels coding for genes involved in growth, metabolism and development.
The use of a dual study design to evaluate the long range versus local sources of contaminants highlighted the importance of trans-Pacific transport in the delivery of PBDEs to coastal BC and the occurrence of local Hg sources in this marine environment. However, consistent with previous studies, our results suggested that PCBs remain the top contaminant of concern for marine mammal health. We also raised questions about the potential exacerbation of toxic risks due to PCBs as a consequence of climate changes currently underway in the Arctic. / Graduate / 0768 / 0383 / marie.t.noel@gmail.com
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Avaliação histopatológica de mamíferos marinhos encalhados no litoral do nordeste brasileiro / Marine mammals of assessment histopathological stranded in the brazilian northeast coastBrito, Ana Paula Domingos 27 February 2015 (has links)
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Previous issue date: 2015-02-27 / Pathological examination of marine mammals carcasses is an important tool to understand the natural morphophysiology as well as the morphological changes associated with some diseases and thus highlight the potential anthropogenic impacts. This work had as aim conduct studies on histopathology of the organs of the dead stranded cetaceans and Sirenia in the Brazilian northeast coast, or that died during the rehabilitation process in Specialized Centers of the Region. For this, samples were taken belonging to the biological collection of Projeto Cetáceos da Costa Branca (PCCB), Associação de Pesquisa e Preservação de Ecossistemas Aquáticos (AQUASIS) and from Centro de Mamíferos Aquáticos (CMA). The tissue samples were submitted to the conventional method of preparing histological slides. Whereas the studied animals belong to different species, age and sex, a general descriptive analysis of the pathological aspects found in each case was carried out. From a total of 237 samples belonging to 66 individuals of the Cetacea order (n = 28) and Sirenia (n = 38), 34,17% (n = 81) exhibited microscopic changes, 54,85% (n = 130) were normal and 10,97% (n = 26) were autolysed. Among the obvious microscopic changes was diagnosed 50% of stomatitis in the oral system (n = 1), the heart showed 6.66% of interstitial fibrosis (n = 2), 10% of haemorrhage (n = 3) and 6.66% myocarditis (n = 2). The lungs showed pulmonary edema in 19% of the analyzes (n = 11), 10% of vascular congestion% (n = 6), 13% of haemorrhage (n = 8), 3% of emphysema (n = 2), 7% full of hemosiderin (n = 4), 3% of interstitial pneumonia (n = 2), 2% of eosinophilic pneumonia (n = 1), 2% of parasitic granuloma (n = 1), 2% of parasitic cyst (n = 1), 2% of traqueíte (n = 1). In the stomach was visualized a hemorrhage (16.66%; n = 1) and in the gut was detected nodular lymphoid hyperplasia (7%; n = 2), enteritis (4%; n = 1), blood vessels congestion (4%; n = 1) and vacuolar degeneration (4%; n = 1). The livers analysis showed 23% of vacuolar degeneration (n = 5), 9% of hepatocellular necrosis (n = 2), 9% moderate deposit of melanin granules (n = 2), 4.54 % of chronic hepatitis (n = 1), 9% of periportal fibrosis (n = 2), 4.54% of abscess (n = 1), 4.54% of congestion (n = 1), 4.54 % of bilestase (n = 1), and 4.54% proliferation of the bile ducts (n = 1). It was possible to observe in the spleen 20% white pulp rarefaction (n = 2), 10% white and red pulp rarefaction (n = 1), and 30% moderate deposition of melanin granules (n = 3). In the pancreas was observed a 50% of centroacinosas cells rarefaction (n = 1). In the kidneys was found 14% of toxix tube nephrosis (n = 4), 7% of multifocal hemorrhaging (n = 2), 14% of vascular congestion (n = 4), 3.44% presence of bacteria (n = 1), 3.44% of proliferative glomerulonephritis (n = 1), 3.44% of micro abscesses (n = 1), 3.44% of severe edema (n = 1), 3.44% of renal cysts (n = 1) and 3.44% of chronic interstitial nephritis (n = 1). In the uteri evaluated were observed 25% of a focal dystrophic calcification (n = 1) and 25% of metritis (n = 1). In the lymph nodes were observed suggestive abnormalities of immunosuppression (25%; n = 1), bleeding (25%; n = 1) and melanose (50%; n = 2). Other findings include rarefaction of the adrenal cells (50%, n = 1), fewer sperm cells into the lumen (14,28%; n = 2) or presence of only spermatogonia in the seminiferous tubules (21,42%; n = 3), and 25% focal hyperplasia of the bladder (n = 1). Despite the changes present in many systems, lung diseases were higher in cetaceans bodies and sirenians stranded on the Brazilian northeast coast / O estudo anatomopatológico das carcaças dos mamíferos marinhos é uma ferramenta importante para conhecer a morfofisiologia natural, bem como as alterações morfológicas associadas com algumas doenças e, desta forma, evidenciar os possíveis impactos antropogênicos. O presente trabalho teve como intuito realizar estudos sobre histopatologia dos órgãos de cetáceos e sirênios. Para isso, foram utilizadas amostras pertencentes ao acervo biológico do Projeto Cetáceos da Costa Branca (PCCB), da Associação de Pesquisa e Preservação de Ecossistemas Aquáticos (AQUASIS) e do Centro de Mamíferos Aquáticos (CMA). Os fragmentos teciduais foram submetidos ao método convencional de preparação de lâminas histológicas. As peças passaram pelos processos de desidratação e diafanização, banho em parafina líquida, inclusão em bloco, e posterior corte em micrótomo rotativo. Os cortes, de quatro a cinco micra de espessura, foram colocados em lâminas lapidadas e submetidos ao método de coloração Hematoxilina-eosina (H.E.), sendo então montados utilizando-se lamínula e resina sintética. Considerando que os animais em estudo pertencem a diferentes espécies, faixas etárias e sexo, foi realizada uma análise descritiva geral dos aspectos patológicos encontrados em cada caso. De um total de 237 amostras pertencentes a 66 indivíduos da ordem Cetacea (n=28) e Sirenia (n=38), 34,17% (n=81) apresentaram alterações microscópicas, 54,85% (n=130) estavam normais e 10,97% (n=26) se encontravam autolisadas. Dentre as alterações microscópicas evidentes foi diagnosticado no sistema bucal 50% de estomatite (n=1), o coração apresentou 6,66% de fibrose intersticial (n=2), 10% de hemorragia (n=3) e 6,66% de miocardite (n=2). Os pulmões mostraram em 19% das análises edema pulmonar (n=11), 10% de congestão vascular (n=6), 13% de hemorragia (n=8), 3% de enfisema (n=2), 7% hemossiderose (n=4), 3% pneumonia intersticial (n=2), 2% de pneumonia eosinofílica (n=1), 2% de granuloma parasitário (n=1), 2% de cisto parasitário (n=1), 2% de traqueíte (n=1). No estômago foi visualizado em um sirênio áreas extensas de hemorragia (16,66%; n=1) e no intestino foi detectado hiperplasia nodular linfóide (7%; n=2), enterite (4%; n=1), congestão dos vasos (4%; n=1) e degeneração vacuolar (4%; n=1). Os fígados analisados mostraram 23% de degeneração vacuolar (n=5), 9% de necrose hepatocelular (n=2), 9% de depósito moderado de grânulos de melanina (n=2), 4,54% de hepatite crônica (n=1), 9% de fibrose periportal (n=2), 4,54% de abscesso (n=1), 4,54% de congestão (n=1), 4,54% de bilestase (n=1), e 4,54% de proliferação dos ductos biliares (n=1). Nos baços foi possível constatar 20% de rarefação de polpa branca (n=2), 10% de rarefação de polpa branca e vermelha (n=1), e 30% de deposição moderada de grânulos de melanina (n=3). No pâncreas foi observado uma rarefação das células centroacinosas em 50% (n=1) das amostras. Nos rins foi encontrado 14% de nefrose tubular tóxica (n=4), 7% de hemorragia multifocal (n=2), 14% de congestão vascular (n=4), 3,44% de presença de bactérias (n=1), 3,44% de glomerulonefrite proliferativa (n=1), 3,44% de microabscessos (n=1), 3,44% de edema severo (n=1), 3,44% de cistos renais (n=1) e 3,44% de nefrite intersticial crônica (n=1). Nos úteros avaliados foi observado 25% de calcificação distrófica focal (n=1) e 25% de metrite (n=1). Nos linfonodos foram observados alterações sugestivas de imunossupressão (25%; n=1), hemorragia (25%; n=1), e melanose (50%; n=2). Outros achados incluíram rarefação das células da adrenal (50%, n=1), poucos espermatozoides no lúmen (14,28%; n=2) ou presença apenas de espermatogônias nos túbulos seminíferos (21,42%; n=3), e 25% de hiperplasia focal da bexiga (n=1). Apesar das alterações presentes em diversos sistemas, as patologias pulmonares foram superiores as demais tanto em órgãos de cetáceos como em sirênios encalhados no litoral do nordeste brasileiro
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Análise tafonômica de osso de mamíferos marinhos provenientes de encalhes no litoral setentrional do Estado do Rio Grande do Norte no semi-árido Nordestino, Brasil / Tafonomic analysis of bones from marine mammals from strads in the northern coast of the state of Rio Grande do Norte in the semi-arid Northeast, BrazilDantas, Camilo Chagas 21 February 2017 (has links)
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Previous issue date: 2017-02-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Taphonomic studies reveals important information about how the environment affects the remains of organisms during the process of decaying. This approach can be used for the study of both ancient and recent organisms. The use of taphonomic techniques to study recent marine mammals were underused, despite its potential. This work aims to study bone material of marine mammals in search of marks left by post-mortem processes related to biotic and abiotic environmental factors in the northern cost of Rio Grande do Norte State, Brasil. According to the taphonomic signatures found in the bone material it was identified weathering processes, abrasion, necrophagy, breaks, taphonomic feedback and human actions. For the northern coast of Rio Grande do Norte skulls have better representation in strandings of marine mammals, but vertebrae have greater reliability for faunal survey. The dynamic tidal influences directly on the samples, acting as a carrier and modifying factor. Also according to the taphomonic signatures found the study area has great heterogeneity regarding the environmental dynamics that produce the signatures studied, adjacent areas can produce different signatures and distant areas can produce similar signatures / Estudos tafonômicos revelam informações importantes sobre como o ambiente afeta os restos de organismos durante o processo de decaimento. Esta abordagem pode ser utilizada tanto para estudo de organismos antigos, como para organismos recentes. A utilização das técnicas de tafonomia para estudo com mamíferos marinhos recentes foram pouco exploradas, apesar de seu potencial. Este trabalho objetiva estudar material ósseo de mamíferos marinhos em busca de marcas deixadas por processos post-mortem relacionados aos fatores ambientais bióticos e abióticos no litoral setentrional do Rio Grande do Norte, Brasil. De acordo com as assinaturas tafonômicas encontradas no material ósseo foi possível identificar processos de intemperismo, abrasão, necrofagia, quebras, retroalimentação tafonômica e ações antrópicas. Para o litoral setentrional do Rio Grande do Norte os crânios possuem uma melhor representação nos encalhes de mamíferos marinhos, porém nota-se que as vértebras possuem maior fidedignidade para levantamento faunístico. A dinâmica das marés influencia diretamente nas amostras, servindo como fator transportador e modificador. Ainda de acordo com as assinaturas tafonômicas encontradas nota-se que a área de estudo possui grande heterogeneidade quanto às dinâmicas ambientais que produzem as assinaturas estudadas, áreas adjacentes podem produzir assinaturas diferentes e áreas distantes podem produzir assinaturas semelhantes / 2017-09-13
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Poluentes orgânicos persistentes (POPs) em toninhas, Pontoporia blainvillei (Mammalia: Cetacea), coletadas no complexo estuarino-lagunar de Cananéia-Iguape, Sudeste do Brasil / Persistent Organic Pollutants (POPs) in toninhas, Pontoporia Blainvillei (Mammalia:Cetacea), incidentally captured in the Cananéia-Iguape estuary complexRenato Miani Gonçalves 30 August 2011 (has links)
A região do complexo estuarino-lagunar de Cananéia-Iguape, situada no litoral sul do estado de São Paulo, é uma área de grande interesse científico. Entre um dos mamíferos marinhos existente nessa região está a Pontoporia blainvillei, a qual teve a sua gordura subcutânea (blubber) analisada para quantificação de POPs. Os valores de concentração média obtida para as 48 amostras analisadas foram, em ordem decrescente: PCBs (1532 ng g-1); DDTs (537 ng g-1); Clordanas (64,0 ng g-1); PBDEs (38,4 ng g-1); Mirex (30,7 ng g-1); Drins (25,2 ng g-1); HCB (9,51 ng g-1); HCHs (7,59 ng g-1) e Endosulfan (6,22 ng g-1). A razão DDT/PCB encontrada foi de 0,35. As concentrações dos POPs entre machos maduros e machos imaturos apresentaram diferenças significativas (com exceção do HCH), sendo os valores encontrados para os machos maduros maiores que os valores obtidos para os machos imaturos; entre os machos maduros e fêmeas imaturas, os grupos de dados foram iguais significativamente (exceção para o DDT e mirex); entre os machos imaturos e fêmeas imaturas, os grupos de dados apresentaram igualdade significativa para todos os POPs. Foi encontrada correlação entre os POPs e a idade dos indivíduos estudados, bem como correlação forte entre PCB x PBDE, PCB x DDT e PBDE x DDT. / Forty eight samples of subcutaneous fat (blubber) of Pontoporia blainvillei were analyzed for the quantitation of persistent organic pollutants (POPs). This marine mammal lives in the estuarine complex of Cananéia-Iguape, São Paulo-BR. The average concentration values of POPs was: PCBs (1532 ng g-1); DDTs (537 ng g-1); Chlordanes (64.0 ng g-1); PBDEs (38.4 ng g-1); Mirex (30.7 ng g-1); Drins (25.2 ng g-1); HCB (9.51 ng g-1); HCHs (7.59 ng g-1) e Endosulfan (6.22 ng g-1). Adult male were those with the highest concentrations of POPs. The DDT/PCBs ratio was equal to 0.35, showing an increase in concentration of PCBs in this area (compared with earlier studies). The concentrations of POPs were different (except for HCH) for mature males and immature males. Between males mature and immature females, the data were significantly (except for DDT and mirex) equal. Between immature males and immature females, data groups were significantly equal for all POPs. Moderate correlation was found between POPs and age, as well as strong correlation between PCB x PBDE, PCB x DDT and PBDE x DDT.
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Ocorrência de compostos organoclorados (pesticidas e PCBs) em mamíferos marinhos da costa de São Paulo (Brasil) e da Ilha Rei George (Antártica). / Occurrence of organochlorine compounds (pesticides and PCBs) in marine mammals from São Paulo coast (Brazil) and King George Island (Antarctica).Gilvan Takeshi Yogui 05 February 2002 (has links)
Os compostos organoclorados causam grande impacto na natureza devido a três características básicas: persistência ambiental, bioacumulação e alta toxicidade. Os mamíferos marinhos estão entre os organismos mais vulneráveis à toxicidade crônica desses contaminantes porque, além de concentrá-los em grande quantidade, a fêmea transfere parte de sua carga ao filhote durante a gestação e a lactação. Assim, o presente trabalho teve como objetivos otimizar uma metodologia para determinação de organoclorados (pesticidas e PCBs) em matrizes gordurosas e verificar a ocorrência dos mesmos na gordura subcutânea de mamíferos marinhos amostrados na costa de São Paulo (Brasil) e na Ilha Rei George (Antártica). No protocolo metodológico otimizado, a extração foi realizada em extrator Soxhlet (8 h) com uma mistura de n-hexano e diclorometano. A etapa de purificação foi feita através de tratamento ácido e o extrato final analisado em cromatógrafo a gás equipado com detector de captura de elétrons (GC-ECD). A performance do método foi avaliada com material de referência certificado, enquadrando-se dentro de padrões internacionais de controle de qualidade. O limite de detecção do método foi em média 2 ng g-1. As análises apontaram DDTs e PCBs como os grupos que mais causam impacto nos cetáceos da costa de São Paulo. Isso refletiu o histórico de ambos no Brasil, tanto em indústria como em agricultura e saúde pública. Em contrapartida, HCHs e HCB não apresentaram concentrações elevadas, fato que pode ser atribuído à volatilidade dos mesmos em regiões de clima tropical. Da mesma maneira, a-clordano, g-clordano e mirex não foram detectados em níveis significativos. A foca de Weddell (Leptonychotes weddelli), habitante do continente antártico, evidenciou as menores cargas de contaminante entre os animais estudados. As toninhas (Pontoporia blainvillei) e o golfinho-nariz-de-garrafa (Tursiops truncatus) também apresentaram baixos níveis de organoclorados. Os botos-cinza (Sotalia fluviatilis) revelaram concentrações de DDT iguais ou superiores a cetáceos da Índia, país onde esse pesticida ainda não está proibido. Já o golfinho-de-dentes-rugosos (Steno bredanensis) mostrou a maior contaminação entre os animais analisados, comparável a espécies estudadas em águas costeiras de países desenvolvidos (onde os organoclorados foram muito utilizados). / Organochlorine compounds cause strong impact on the nature, as a consequence of three basic characteristics: environmental persistence, bioaccumulation, and high toxicity. The marine mammals are one of the most vulnerable organisms to the chronic toxicity of these contaminants. Besides the high concentration in the body, the female transfers part of her load to the offspring during gestation and lactation. The aim of this study was (1) the optimization of a methodology for determining chlorinated hydrocarbons (pesticides and PCBs) in fatty biological matrices and (2) the analysis of organochlorines in marine mammals blubber sampled along São Paulo coast (Brazil) and King George Island (Antarctica). According to the optimized methodology, the extraction was carried out in Soxhlet apparatus (8 h) with a mixture of n-hexane and dichloromethane. The clean-up was carried out with acid treatment and the resulting extract injected into gas chromatography coupled to electron capture detector (GC-ECD). The method performance was evaluated with certified reference material and fitted for international standards of control quality. The mean method detection limit was 2 ng g-1. DDTs and PCBs were the most concentrated organochlorines in the cetaceans from São Paulo coast. These findings reflected their past usage in Brazil by industry, agriculture, and public health. On the other hand, both HCHs and HCB were not found in high concentration likely due to their volatility in tropical climate areas. Mirex, a-chlordane and g-chlordane were not detected in elevated levels. The Weddell seal (Leptonychotes weddelli), from Antarctic continent, presented the smallest load among the studied animals. As the same way, the franciscanas (Pontoporia blainvillei) and the bottlenose dolphin (Tursiops truncatus) presented low organochlorine levels. The marine tucuxi (Sotalia fluviatilis) showed equal or higher DDT concentration than Indian cetaceans where that pesticide is still in use. The rough-toothed dolphin (Steno bredanensis) revealed the greatest contamination among the analyzed animals, comparable to species studied in the coastal waters of developed countries (where organochlorines were extensively used).
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