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The Influence of Genetic Variation on Susceptibility of Common Bottlenose Dolphins (<italic>Tursiops truncatus</italic>) to Harmful Algal BloomsCammen, Kristina Marstrand January 2014 (has links)
<p>The capacity of marine organisms to adapt to natural and anthropogenic stressors is an integral component of ocean health. Harmful algal blooms (HABs), which are one of many growing threats in coastal marine ecosystems, represent a historically present natural stressor that has recently intensified and expanded in geographic distribution partially due to anthropogenic activities. In the Gulf of Mexico, HABs of <italic>Karenia brevis</italic> occur almost annually and produce neurotoxic brevetoxins that have been associated with large-scale mortality events of many marine species, including the common bottlenose dolphin (<italic>Tursiops truncatus</italic>). The factors resulting in large-scale dolphin mortality associated with HABs are not well understood, particularly in regards to the seemingly different impacts of HABs in geographically disjunct dolphin populations. My dissertation investigates a genetic basis for resistance to HABs in bottlenose dolphins in central-west Florida and the Florida Panhandle. I used both genome-wide and candidate gene approaches to analyze genetic variation in dolphins that died putatively due to brevetoxicosis and live dolphins from the same geographic areas that survived HAB events. Using restriction site-associated DNA sequencing, I identified genetic variation that suggested both a common genetic basis for resistance to HABs in bottlenose dolphins across the Gulf coast of Florida and regionally specific resistance. Many candidate genes involved in the immune, nervous, and detoxification systems were found in close genomic proximity to survival-associated polymorphisms throughout the bottlenose dolphin genome. I further investigated two groups of candidate genes, nine voltage-gated sodium channel genes selected because of their putative role in brevetoxin binding and four major histocompatibility complex (MHC) loci selected because of their genomic proximity to a polymorphism exhibiting a strong association with survival. I found little variation in the sodium channel genes and conclude that bottlenose dolphins have not evolved resistance to HABs via mutations in the toxin binding site. The immunologically relevant MHC loci were highly variable and exhibited patterns of genetic differentiation among geographic regions that differed from neutral loci; however, genetic variation at the MHC also could not fully explain variation in survival of bottlenose dolphins exposed to HABs. In my final chapter, I consider the advantages and drawbacks of the genome-wide approach in comparison to a candidate gene approach and, as laid out in my dissertation, I recommend using both complementary approaches in future investigations of adaptation in genome-enabled non-model organisms.</p> / Dissertation
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Abundance, behaviour and habitat use patterns of Indo-Pacific bottlenose dolphins (<em>Tursiops aduncus</em>) in the Clarence and Richmond River estuaries in northern New South Wales, AustraliaFury, Christine Ann Unknown Date (has links)
Bottlenose dolphins (Tursiops spp.) are a widely studied species in marine habitats, however, information on estuarine populations in Australia is very limited. To fully understand the importance of estuaries as habitats for dolphins there needs to be clear quantitative data on dolphin populations and their habitat use in estuaries. This study provides the first published data on Indo-Pacific bottlenose dolphins (Tursiops aduncus) abundance estimates, site fidelity, individual ranging patterns, habitat use, flood impacts and sexual segregation patterns over a 3- year period in the Clarence River (CR) and Richmond River (RR) estuaries in northern New South Wales, Australia.The results indicate that, at present, the CR estuary is sustaining a larger dolphin community with a predominantly resident population compared to the RR estuary, which supports a smaller community with lower site fidelity. The CR estuary dolphin abundance estimate of 71 (62-81 95% CI, CV = 0.07) is more than twice the size of the RR estuary abundance estimate of 34 (19- 49 95% CI, CV = 0.23). Differences in site fidelity were observed between the estuaries with 60% and 37% of identified dolphins determined as residents, 26% and 21% as occasional visitors, and 14% and 42% as transients for the CR and RR, respectively. Resource partitioning was apparent in both estuaries with the mean distance resident dolphins were found upstream from the River mouth being greater than for the occasional visitors and transients.Tursiops aduncus was seen all year round in the CR and RR estuaries, with peak sightings occurring in spring at both sites. In the CR the dolphin population showed consistent seasonal fluctuations, whereas this did not occur in the RR population. In the CR the largest spatial distribution of dolphins in the estuary was observed in spring and winter, while in summer they were primarily restricted to the main estuary channel. Different behaviours that were observed; feeding, socialising, travelling, and milling and resting, were found to be influenced by season, tidal phase and tidal range. In both estuaries the core habitat areas used by the population for feeding consisted of areas with considerable slope near the edge of tidal sand banks, adjacent to deeper channels at the entrances of canals, creeks or artificial breakwalls. In addition, the core habitat areas used by the population for milling and resting behaviour in both estuaries occurred in shallow, sheltered areas, often associated with seagrass beds. Socialising occurred more frequently in the CR throughout most of the deeper waters of the estuary, whereas in the RR it was primarily restricted to a small area of medium depth in the estuary.The major determinant of T. aduncus occupancy in the two estuaries was the flood events that occurred, which resulted in the dolphins abandoning the estuary. The mean predicted probabilities for sighting dolphins during non-flood periods were 0.87 and 0.71, during a flood 0.21 and 0.04, and during a post-flood recovery period 0.83 and 0.80 in the CR and RR, respectively. Principal Components Analysis (PCA) showed that when the dolphins were absent from the estuaries, three components were extracted from the water quality parameters in the CR, and two components in the RR. High loadings from the PCA were associated with the changing salinity, turbidity, pH, dissolved oxygen and temperature associated with the flood events. The return of the dolphins to the estuary following a flood depended on the length and severity of the flood event, but generally the dolphins seemed to prefer waters with salinity levels above 29 ‰. This could be associated with higher salinities being important for their physiological health, or because their prey returned to the estuaries during these higher salinity conditions, more likely a combination of both of these factors.Sexual segregation patterns were observed in T. aduncus populations with mixed gender and female groups mainly recorded in the CR, whereas in the RR female groups dominated the estuary. In the CR, significant differences occurred in sightings between the mixed and female groups in relation to water depth and behaviour. Mixed gender groups were sighted predominantly in deeper water and were involved in social behaviour including sexual behaviour and male herding of females. In contrast, the female groups were observed across all water depths, predominately feeding and also participating in more milling and resting behaviours.The high occurrence of aggressive herding behaviour by males in the CR was significantly different at varying depths, tides and seasons, occurring more often in deeper water, at higher tides and in non-breeding seasons. Female groups were found to utilise the small, shallow tributaries and travel for longer distances up these smaller tributaries than the mixed groups, which were concentrated in the deeper main channel of the estuary.The deeper water of the channels may facilitate the males in herding the females, while the female groups’ habitat selection of shallow estuary areas may provide a sanctuary from aggressive males, access to suitable prey items or prey density for mothers and their calves, or a combination of these factors.This study has provided the first detailed research on T. aduncus dolphin population dynamics, habitat use, occupancy and sexual segregation patterns in two Australian subtropical estuaries. To ensure the long-term survival of both of these dolphin populations, management of future increased anthropogenic disturbances from boat traffic, pollution, dolphin watching, industrial or urban development, over-fishing and habitat degradation of the catchment is needed. Good quality water conditions, the protection of the core feeding areas and small shallow tributaries for females and their calves, and sheltered areas for resting behaviour all need to be maintained for the continued conservation of these important dolphin populations.
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Abundance, behaviour and habitat use patterns of Indo-Pacific bottlenose dolphins (<em>Tursiops aduncus</em>) in the Clarence and Richmond River estuaries in northern New South Wales, AustraliaFury, Christine Ann Unknown Date (has links)
Bottlenose dolphins (Tursiops spp.) are a widely studied species in marine habitats, however, information on estuarine populations in Australia is very limited. To fully understand the importance of estuaries as habitats for dolphins there needs to be clear quantitative data on dolphin populations and their habitat use in estuaries. This study provides the first published data on Indo-Pacific bottlenose dolphins (Tursiops aduncus) abundance estimates, site fidelity, individual ranging patterns, habitat use, flood impacts and sexual segregation patterns over a 3- year period in the Clarence River (CR) and Richmond River (RR) estuaries in northern New South Wales, Australia.The results indicate that, at present, the CR estuary is sustaining a larger dolphin community with a predominantly resident population compared to the RR estuary, which supports a smaller community with lower site fidelity. The CR estuary dolphin abundance estimate of 71 (62-81 95% CI, CV = 0.07) is more than twice the size of the RR estuary abundance estimate of 34 (19- 49 95% CI, CV = 0.23). Differences in site fidelity were observed between the estuaries with 60% and 37% of identified dolphins determined as residents, 26% and 21% as occasional visitors, and 14% and 42% as transients for the CR and RR, respectively. Resource partitioning was apparent in both estuaries with the mean distance resident dolphins were found upstream from the River mouth being greater than for the occasional visitors and transients.Tursiops aduncus was seen all year round in the CR and RR estuaries, with peak sightings occurring in spring at both sites. In the CR the dolphin population showed consistent seasonal fluctuations, whereas this did not occur in the RR population. In the CR the largest spatial distribution of dolphins in the estuary was observed in spring and winter, while in summer they were primarily restricted to the main estuary channel. Different behaviours that were observed; feeding, socialising, travelling, and milling and resting, were found to be influenced by season, tidal phase and tidal range. In both estuaries the core habitat areas used by the population for feeding consisted of areas with considerable slope near the edge of tidal sand banks, adjacent to deeper channels at the entrances of canals, creeks or artificial breakwalls. In addition, the core habitat areas used by the population for milling and resting behaviour in both estuaries occurred in shallow, sheltered areas, often associated with seagrass beds. Socialising occurred more frequently in the CR throughout most of the deeper waters of the estuary, whereas in the RR it was primarily restricted to a small area of medium depth in the estuary.The major determinant of T. aduncus occupancy in the two estuaries was the flood events that occurred, which resulted in the dolphins abandoning the estuary. The mean predicted probabilities for sighting dolphins during non-flood periods were 0.87 and 0.71, during a flood 0.21 and 0.04, and during a post-flood recovery period 0.83 and 0.80 in the CR and RR, respectively. Principal Components Analysis (PCA) showed that when the dolphins were absent from the estuaries, three components were extracted from the water quality parameters in the CR, and two components in the RR. High loadings from the PCA were associated with the changing salinity, turbidity, pH, dissolved oxygen and temperature associated with the flood events. The return of the dolphins to the estuary following a flood depended on the length and severity of the flood event, but generally the dolphins seemed to prefer waters with salinity levels above 29 ‰. This could be associated with higher salinities being important for their physiological health, or because their prey returned to the estuaries during these higher salinity conditions, more likely a combination of both of these factors.Sexual segregation patterns were observed in T. aduncus populations with mixed gender and female groups mainly recorded in the CR, whereas in the RR female groups dominated the estuary. In the CR, significant differences occurred in sightings between the mixed and female groups in relation to water depth and behaviour. Mixed gender groups were sighted predominantly in deeper water and were involved in social behaviour including sexual behaviour and male herding of females. In contrast, the female groups were observed across all water depths, predominately feeding and also participating in more milling and resting behaviours.The high occurrence of aggressive herding behaviour by males in the CR was significantly different at varying depths, tides and seasons, occurring more often in deeper water, at higher tides and in non-breeding seasons. Female groups were found to utilise the small, shallow tributaries and travel for longer distances up these smaller tributaries than the mixed groups, which were concentrated in the deeper main channel of the estuary.The deeper water of the channels may facilitate the males in herding the females, while the female groups’ habitat selection of shallow estuary areas may provide a sanctuary from aggressive males, access to suitable prey items or prey density for mothers and their calves, or a combination of these factors.This study has provided the first detailed research on T. aduncus dolphin population dynamics, habitat use, occupancy and sexual segregation patterns in two Australian subtropical estuaries. To ensure the long-term survival of both of these dolphin populations, management of future increased anthropogenic disturbances from boat traffic, pollution, dolphin watching, industrial or urban development, over-fishing and habitat degradation of the catchment is needed. Good quality water conditions, the protection of the core feeding areas and small shallow tributaries for females and their calves, and sheltered areas for resting behaviour all need to be maintained for the continued conservation of these important dolphin populations.
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Caracterização da reserva faunística costeira de Tibau do Sul – REFAUTS, Rio Grande do Norte: proposta de ordenamento do turismoNascimento, Larycynthia Luana Sousa do 23 March 2016 (has links)
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Previous issue date: 2016-03-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The Coast Wildlife Reserve of Tibau do Sul - REFAUTS is located at Pipa bay, southern coast of Rio Grande do Norte, and has as main objectives the conservation of coastal and marine biodiversity, especially marine turtles and Guiana dolphin, Sotalia guianensis, often found in the Madeiro and Dolphins bay. Given the growth in ecotourism at REFAUTS in the past decade, this study had as main objectives: (i) describe the economic-tourist activity in this Reserve; (ii) characterize the dolphin watching and the tourist profile that participated of the tours; (iii) evaluate the intensity of the tourist flow in this Reserve and (iv) estimate the tourism carrying capacity of the REFAUTS. To this end, there were five expeditions to the study area- three expeditions in 2014 and two expeditions in 2015, totaling 19 sampling days. Data collection in the study area occurred between 9:00h and 16:00h. In this study, we recorded 29 tourism enterprises at Madeiro bay and 5 tourism enterprises at Dolphins bay. We recorded 11 licensed vessels conducting tours for Guiana dolphin watching at REFAUTS. The tours occurred from 9:00h to 16:00h, with greater tourist flow between 11:00h and 11:30h. Tourists that participated in boat tours at REFAUTS were mostly young women, ofBrazilian national, with higher education and originating of the southeastern Brazil. From the evaluation of tourist flow, the number of tourists, surfers and kayaks was higher in Madeiro bay than in the Dolphins bay. However, the number of vessels did not differ between the two bays. The number of tourists registered in the study area was higher than the estimated tourism carrying capacity. Although REFAUTS was created in 2006, it still does not have a management plan for tourism planning. This study refers to the first proposal for tourism planning at REFAUTS, based on the current tourist flow, on the tourist profile and on the carrying capacity of the Reserve / A Reserva Faunística Costeira de Tibau do Sul – REFAUTS localiza-se na praia de Pipa, litoral sul do Rio Grande do Norte, e tem como principais objetivos a conservação da biodiversidade costeira e marinha, especialmente as tartarugas marinhas e o boto-cinza, Sotalia guianensis, frequentemente encontrado nas enseadas do Madeiro e dos Golfinhos. Tendo em vista o crescimento do ecoturismo na REFAUTS na última década, este estudo teve como principais objetivos: (i) descrever a atividade econômico-turística nesta Reserva; (ii) caracterizar o turismo de observação de botos-cinza a partir de embarcação e o perfil do turista que realizou os passeios; (iii) avaliar a intensidade do fluxo turístico nesta Reserva e (iv) estimar a capacidade de carga turística da REFAUTS. Para tanto, foram realizadas cinco expedições à área de estudo – três expedições em 2014 e duas expedições em 2015, totalizando 19 dias de amostragem. A coleta de dados na área de estudo ocorreu entre 9:00h e 16:00h. Neste estudo, nós registramos 29 empreendimentos turísticos na enseada do Madeiro e 5 empreendimentos turísticos na enseada dos Golfinhos. Foram registradas 11 embarcações licenciadas realizando os passeios para observação de botos-cinza na REFAUTS. Os passeios ocorreram das 9:00h as 16:00h, com maior fluxo de passeios entre 11:00h e 11:30h. Os turistas que realizaram os passeios de barco na REFAUTS foram principalmente mulheres jovens, de nacionalidade brasileira, com escolaridade superior e originárias da região sudeste do Brasil. A partir da avaliação do fluxo turístico, o número de turistas, de surfistas e de caiaques foi maior na enseada do Madeiro do que na enseada dos Golfinhos. Contudo, o número de embarcações não diferiu entre as duas enseadas. O número de turistas registrado na área de estudo foi superior a capacidade de carga turística estimada. Embora a REFAUTS tenha sido criada em 2006, esta ainda não dispõe de um plano de manejo para ordenamento do turismo. Este estudo trata-se da primeira proposta de ordenamento do turismo naREFAUTS, tendo como base o atual fluxo turístico, o perfil do turista e a capacidade de carga da Reserva / 2017-02-09
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Ocorr?ncia e Intera??es de Rec?m-nascidos e Filhotes de golfinho-rotador Stenella longirostris na Ba?a dos Golfinhos, Fernando de NoronhaHavukainen, Liisa 12 September 2009 (has links)
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Previous issue date: 2009-09-12 / Studies indicate that spinner dolphins use the Ba?a dos Golfinhos, in Fernando de Noronha Archipelago, for resting, reproduction, parental care and protection against shark attacks. The present study had the purpose of verifying the seasonality of spinner dolphin newborns and calves in relation to the months of the year and the pluviometric seasons (dry and rainy), as
well as their interaction with the number and gender of accompanying adults and their positioning in relation to the adults (vertical, horizontal, and depth) in the above mentioned bay. The analysis were made out of photo records of dolphins collected between 2000 and 2006 (seasonality) and between 1995 and 2006 (interaction) both using ad libitum sampling method during free dives. To determine the age category, the reason between the smaller dolphin s total body length and the bigger dolphin s total body length was calculated. The dolphins were then divided into three age groups: adults, newborns and calves. Those with total body length ≥ 170cm were considered adults, newborns up to 105cm, and calves from 106cm to 128cm. In addition, the secondary characters described in literature were used to identify newborns and calves. The adults had dimensions of total lenght ≥170cm , the newborns until 105cm and calves between 106cm and 128cm. I addition, secondary characteristics described in the literature were used to indentify newborns and calves. The
number of spinner dolphin newborns was greater in the month of April and higher during the rainy season. Throughout the months and pluviometric seasons (pluviometer/pluvial metric), the number of calves did not have a significant difference. Concerning to the presence of newborns and calves age groups at Ba?a dos Golfinhos, there was not a significant difference. It was possible to identify the gender of the escorting adults as (42), 95.24% being females and 4.76% males. Newborns were more frequently seen in the company of two adults, whereas calves were more often accompanied by more than two adults However, there was not a significant difference for the newborns, whereas for the calves there was a significant difference for those classified as loners and those accompanied by more than two adults. When in vertical positioning, the newborns and calves were more frequently observed in inferior position with some difference demonstrated between some of that. While in horizontal positioning both age groups were more often seen in posterior position, also with differences between them. In the depth perspective newborns and calves were positioned anterior, however with significant difference for the calves. The occurrence of a peak of newborns in the months of April may indicate the existence of a birth seasonality pattern for the beginning of the rainy season, with births scattered throughout the year. The results for the positions and escorting of newborns and calves are related to protection and suckling. These conditions reinforce the importance of the area when it comes to the care for offspring, which calls for the creation of conservation rules to the area, especially during those months with greater occurrence of newborns / Estudos indicam que golfinhos-rotadores utilizam a Ba?a dos Golfinhos de Fernando de Noronha para descanso, cuidado parental, acasalamentos e prote??o contra tubar?es. O presente estudo objetivou verificar a sazonalidade de ocorr?ncia de rec?m-nascidos e filhotes de golfinhos-rotadores durante os meses do ano e esta??es pluviom?tricas (seca e chuvosa), e
a intera??o destes quanto ? quantidade e sexo de adultos acompanhantes, posicionamento dos rec?m-nascidos e filhotes em rela??o aos adultos (entre as dimen??es vertical, horizontal e profundidade) na referida enseada. As an?lises foram desenvolvidas a partir de registros fotogr?ficos dos golfinhos coletados entre 2000 e 2006 (sazonalidade) e entre 1995 e 2006 (intera??o), ambos atrav?s de amostragem ad libitum em mergulhos livres. Para a determina??o das faixas et?rias, calculou-se a raz?o entre o comprimento total do golfinho menor pelo maior mais pr?ximo a ele na mesma fotografia. Os golfinhos foram divididos em tr?s classes et?rias: adultos, rec?m-nascidos e filhotes. Indiv?duos adultos apresentavam propor??es de comprimento total ≥170cm, rec?m-nascidos at? 105cm e filhotes entre 106cm e 128cm. Em adi??o, foram utilizados caracteres secund?rios descritos na literatura para identificar rec?m-nascidos e filhotes. O maior n?mero de rec?m-nascidos foi registrado no
m?s de abril e maior na esta??o chuvosa. Em rela??o ao n?mero de filhotes, n?o houve diferen?a significativa ao longo dos meses e nas esta??es pluviom?tricas. N?o houve diferen?a significatica com rela??o faixas et?rias de rec?m-nascidos e filhotes presentes na Ba?a dos Golfinhos. Entre os adultos acompanhando rec?m-nascidos e filhotes, no caso em
que foi poss?vel identificar o sexo dos indiv?duos (42), 95,24% eram f?meas e 4,76% machos. Os rec?m-nascidos estavam em companhia mais freq?ente de 2 adultos, e os filhotes com mais de 2 adultos. Por?m, n?o foi registrada diferen?a para os rec?m-nascidos, ao contr?rio dos filhotes, que diferiram significativamente entre estar sozinho e os demais acompanhamentos. Com rela??o aos posisionamentos nas tr?s dimen??es analisadas, para o posicionamento vertical os rec?m-nascidos e filhotes estavam mais na posi??o inferior,
demonstrando diferen?as entre algumas delas. Para a posi??o horizontal, os rec?m-nascidos e filhotes encontravam-se mais posterior, tamb?m com diferen?as entre elas. Com rela??o ? perspectiva profundidade, rec?m-nascidos e filhotes estavam posicionados na frente, por?m apresentou-se diferen?a significativa somente para os filhotes entre as demais. A presen?a do pico de ocorr?ncia de rec?m-nascidos no m?s de abril pode indicar a exist?ncia de um padr?o sazonal de nascimento no in?cio da esta??o das chuvas, por?m tamb?m com a exist?ncia de nascimentos difusos no decorrer do ano. As posi??es e acompanhamentos dos rec?m-nascidos e filhotes se relacionam ? prote??o e amamenta??o. Essas condi??es refor?am a import?ncia
da ?rea para o cuidado da prole, necessitando de regras de acesso ? ?rea, principalmente durante os meses com maior ocorr?ncia de rec?m-nascidos
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Varia??o di?ria e anual de freq??ncia e atividade do Boto Cinza Sotalia guianensis em Pipa, Nordeste do BrasilSilveira, Fernando Roberto Guilherme 22 May 2006 (has links)
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Previous issue date: 2006-05-22 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The aim of this study was to investigate the daily and annual variation in frequency and in activity of an estuarine dolphin population, Sotalia guianensis, in Brazilian northeastern. Thus we estimated the daily variation and seasonality in frequency of adult and immature and in behavior of socialization, aerial activity, foraging of a boto equatorial population in the Curral inlet (6?13 00 S; 35?3 36 W). We detect some variation. Thus we associate the daily variation with daily period, tide fluctuation and annual season. And the seasonality variation we associate with the fotoper?odo and precipitation variation. From October 1999 to September 2003, through collect four times at month, we made instantaneous record at each five minute in six hours of survey. The surveys hours were ranged into light time of 24 hours, that is, between 06:00 and 17:00 o clock. These observations were developed simultaneous for two observers in a land-based survey at coastline cliff top of which observer have a fully visualization of whole inlet. We found that animals were more active and frequent during the morning. They were more active during low tide than high tide. However they did not show association with tide. We found yet that in a period from June to November (winter-spring) there was the highest socialization, aerial activity and foraging frequency. However adult and immature individual number did not have significance variation along the year. The larger concentration of this behaviors were not associate with photoperiod neither precipitation in the region. These results showed the existence of behavioral daily variation and seasonality in a species that live in equatorial region / Neste estudo avaliamos a varia??o di?ria e anual na freq??ncia de adultos e imaturos e nos comportamentos de socializa??o, atividade a?rea e forrageio numa popula??o de boto cinza, Sotalia guianensis, na Enseada do Curral (6?13 00 S; 35?3 36 W), no nordeste brasileiro. Ap?s detectarmos algumas varia??es procuramos associ?-las a par?metros ambientais. Associamos as varia??es di?rias ao per?odo do dia, ?s varia??es da mar? e ao per?odo do ano; e as sazonais, a varia??o do fotoper?odo e da precipita??o. De Outubro de 1999 a Setembro de 2003, atrav?s de coletas quatro vezes ao m?s, efetuaram-se registros instant?neos a cada 5min, em seis horas de observa??o. As horas de observa??o estiveram inseridas dentro da fase clara das 24 horas, ou seja, no intervalo das 06:00 h as 17:00 h. Essas observa??es eram realizadas simultaneamente por dois observadores, num ponto fixo no alto da fal?sia a partir do qual visualizava-se toda a enseada. Observamos que os animais s?o mais ativos e freq?entes pela manh?. N?o apresentaram associa??o com a mar?, apesar de apresentarem maior atividade na mar? baixa e menor atividade na mar? alta. Quanto ? sazonalidade, observamos ainda, que no per?odo de junho a novembro (inverno e primavera) houve maior freq??ncia dos comportamentos de socializa??o, atividade a?rea e forrageio embora o n?mero de indiv?duos (adultos e imaturos) n?o tenha variado significativamente ao longo do ano. A maior concentra??o desses comportamentos n?o foi associada ao fotoper?odo e nem ? precipita??o na regi?o. Desses resultados, mostramos a exist?ncia de varia??o di?ria e sazonalidade comportamental nesta esp?cie, mesmo nas regi?es equatoriais
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O uso do boto-cinza (Sotalia guianensis) como sentinela da poluição continental por compostos organoclorados (DDT, PCB, HCH, HCB e Mirex) em baías costeiras do Estado do Rio de Janeiro / The use of the Guiana dolphin (Sotalia guianensis) as sentinel environmental pollution by organochlorine compounds (DDT, PCB, HCH, HCB and Mirex) coastal bays in the State of rio de JaneiroLara Gama Vidal 16 September 2010 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Concentrações de compostos organoclorados (DDTs, PCBs, HCHs, Mirex e HCB) foram determinadas em camadas externas e internas do tecido adiposo subcutâneo de 17 botos-cinza (Sotalia guianensis) da região Sudeste do Brasil. Não houve diferenças estatísticas significativas entre os estratos, relativo aos 37 compostos determinados, assim como ΣDDT, ΣPCB, ΣHCH, e as razões p,p-DDE/ΣDDT e ΣDDT/ΣPCB. Entretanto, foram observadas diferenças significativas
nas concentrações de alguns compostos organoclorados de animais encalhados ou capturados acidentalmente quando comparados com animais biopsiados remotamente, sendo assim as comparações entre esses dois conjuntos de dados,
devem ser vistas com cuidado. No presente estudo, as concentrações dos compostos organoclorados foram determinadas em biópsias de botos-cinza obtidas de 2007 a 2009, nas baías de Sepetiba (n=13) e Ilha Grande (n=11), Sudeste do Brasil. As concentrações (ng/g de lipídio) variaram de <LD a 26 621 para o ΣDDT, de 256 a 60 195 para o ΣPCB; de <LD a 2 296 para ΣHCH; de 142 a 1 088 para o Mirex, bem como de <LD a 35 para o HCB. Com relação à análise discriminante, os dados dos machos capturados acidentalmente gerados no presente estudo foram analisados juntamente com dados dos machos de um estudo recente que utilizou amostras do tecido adiposo subcutâneo de botos-cinza capturados acidentalmente. Através dessa análise, foi possível verificar que as populações de boto-cinza de 2 baías costeiras vizinhas (Sepetiba e Guanabara), bem como da Baía de Paranaguá, apresentaram padrões distintos de acumulação dos compostos organoclorados. O último achado demonstra a existência de separações ecológicas entre os botoscinza
a partir de diferentes áreas, o que constitui informação de grande importância para a conservação e o manejo da espécie / Organochlorine compound (OC) concentrations (DDTs, PCBs, HCHs, Mirex and HCB) were determined in inner and outer strata from blubber of 17 Guiana dolphins (Sotalia guianensis) from southeast Brazil. There was no statistically significant difference between the strata concerning the 37 determined compounds, ΣDDT, ΣPCB, ΣHCH as well as regarding the p,p-DDE/ΣDDT and the ΣDDT/ΣPCB ratios. However, significant differences were found in concentrations of some organochlorine compounds in stranded or incidentally captured animals and remotely biopsied , thus comparisons between these two sets of data should be viewed with caution. In the present study, OC concentrations were determined in biopsy samples from Guiana dolphins obtained from 2007 to 2009, in Sepetiba (n=13) and Ilha Grande (n=11) bays, southeast Brazil. Concentrations (ng/g lipids) varied from <LD to 26 621 for ΣDDT, from 256 to 60 195 for ΣPCB; from <LD to 2 296 for ΣHCH; from 142 to 1 088 for Mirex; as well as from <LD to 35 for HCB. Concerning the discriminant analysis, the data from males incidentally captured generated by the present study were analyzed together with data from males to a recent study that dealt with blubber samples from males incidentally captured Guiana dolphins. Through this analysis, it was possible to verify that the Guiana dolphin populations from 2 neighboring coastal bays (Sepetiba and Guanabara), as well as from Paranaguá Bay, present differentiation on the OC accumulation patterns. This latter finding demonstrates the existence of ecological separations among Guiana dolphins
from different areas, which constitutes information of importance for conservation and management purposes.
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Poluentes Orgânicos Persistentes (POPs) em toninhas (Pontoporia blainvillei; Cetacea, Pontoporiidae) acidentalmente capturadas em operações de pesca no litoral sul de São Paulo / Persistent Organic Pollutants (POPs) in franciscana (Pontoporia blainvillei; Cetacea, Pontoporiidae) accidentally caught in fishing operations in the south coast of São PauloAna Paula Moreno Barbosa 06 May 2015 (has links)
Os poluentes orgânicos persistentes (POPs) são acumulados em tecidos gordurosos dos organismos vivos em concentrações relativamente altas em animais do topo da cadeia alimentar, como os golfinhos. Os objetivos deste trabalho foram avaliar a distribuição e acumulação de POPs em tecidos (gordura, fígado, rim e músculo) de toninhas (Pontoporia blainvillei) do litoral sul de São Paulo, bem como as diferenças/similaridades entre gênero e maturidade sexual e a transferência via placenta. Os valores de concentração mediana (ng g-1; peso úmido) para as 16 amostras de gordura, fígado, rim e músculo, respectivamente, foram: PCBs (987; 19,2; 5,08; 4,41); DDTs (550; 10,3; 2,67; 1,89); PBDEs (32,7; 0,230; 0,095; 0,050); Mirex (21,5; 0,457; 0,168; 0,083); HCB (15,4; <0,360; <0,360; <0,144); HCHs (<0,870; 2,20; <0,218; <0,087); Clordanas (<1,45; <0,362; <0,362; <0,145). Os machos jovens apresentaram as maiores concentrações dos POPs, seguidos pelos machos adultos, fêmeas jovens, fêmeas adultas e fetos. Foi observada transferência dos contaminantes das fêmeas gestantes para seus fetos entre 14 a 28% para PCBs e 19 a 45% para DDTs. A gordura apresentou correlação significativa com os demais tecidos estudados para acumulação dos PCBs, DDTs e PBDEs sugerindo a sua representatividade para estudos desses POPs em toninhas. / Persistent organic pollutants (POPs) are accumulated in fatty tissues of organisms in relatively high concentrations in animals in high position of the food chain such as dolphins. The aims of this study were to evaluate the distribution and accumulation of POPs in tissues (blubber, liver, kidney and muscle) of franciscana dolphin (Pontoporia blainvillei) collected on the southern coast of São Paulo as well as differences/similarities between genre and sexual maturity and the transplacental transfer. The values of median concentration (ng g-1; wet weight) for 16 samples of blubber, liver, kidney and muscle, respectively, were: PCBs (987; 19,2; 5,08; 4,41); DDTs (550; 10,3; 2,67; 1,89); PBDEs (32,7; 0,230; 0,095; 0,050); Mirex (21,5; 0,457; 0,168; 0,083); HCB (15,4; <0,360; <0,360; <0,144); HCHs (<0,870; 2,20; <0,218; <0,087); Chlordanes (<1,45; <0,362; <0,362; <0,145). POPs concentrations were higher in young males followed by adult males, young females, adult females and fetuses. Maternal transfer of POPs to the fetuses was between 14 to 28% for PCBs and 19 to 45% for DDTs. Blubber showed a significant correlation with the other tissues studied for PCBs, DDTs and PBDEs suggesting its representativeness for evaluation of these POPs in franciscana dolphin.
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Changes in Tursiops truncatus Distribution and Behavior in the Drowned Cayes, Belize, and Correlation to Human ImpactsGarcia, Jazmin 22 July 2016 (has links)
Human interaction greatly influences the behavior and distribution of bottlenose dolphins (Tursiops truncatus). This project focuses on the distribution and behavior of bottlenose dolphins in the Drowned Cayes, Belize. Prior to the 2000s, the area was relatively undeveloped and undisturbed and had minimal human activity. Since the turn of the millennium, development and ecotourism activity has flourished in the area, increasing by more than 800,000 visitors from 1998-2006. Boat-based surveys were conducted in 2015 and were combined with previous survey data collected from 2005-2012 and compared to behavioral survey results from 1999-2000. Total dolphin observation time as a percent of total survey time and average number of dolphins per sighting were 17.2% and 2.7 in 1999-2000 and 10.8% and 1.6 for 2005-2015. The low number of dolphins and the low observation times suggest that the dolphin population in the Drowned Cayes have decreased since the 1990s. Eighty-nine percent of the total observation time for 2015 occurred on days in which there were zero cruise ships in the area suggesting that this decline may be in relation to increased human activity. Furthermore, foraging was the main behavior observed for both 1999-2000 and 2005-2015 data sets, suggesting that the Drowned Cayes area is used as a foraging ground. However, in 1999-2000 the foraging percentage was significantly higher than the 2005-2015 data set, dropping 28.9% and there was a 23.6% increase in traveling behavior between the two data sets. This could be a result of increased human activity.
Additionally, survey photographs and results were used in the creation of the first dolphin photo identification database for the country. The guidelines used for photo analysis for photo quality and fin distinctiveness were tested to determine if they are easy to use and give consistent and reliable results regardless of judge. An intraclass correlation model calculated substantial agreement (ICC = 0.7) between judges’ scores, demonstrating consistent results, regardless of experience level. Therefore, the guideline can be used as a standard among multiple researchers.
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Abundance of Spinner Dolpin (Stenella longirostris) in the Southern Tanon Strait, Philippines 2004-2007Stronach, Rachel 01 April 2012 (has links)
Spinner dolphins (Stenella longirostris) were surveyed and photographed during the Spring/Summer of 2004-2007 in the Southern Tañon Strait region of the Philippines. Over 17,000 images of dorsal fins were taken during the study period for photoidentification purposes. The study area (approximately 100 Km2) is a popular site for cetacean-watching and more recently underwent oil exploration and drilling. A photographic database of 329 unique spinner dolphin dorsal fins was produced, and used to assess abundance and life history characteristics using DARWIN software. An overall abundance estimate (2004-2007) of 1118 individuals (990-1246 with a 95% confidence interval) was obtained using the POPAN feature of MARK software. These mark-recapture results reveal that approximately 28% (n= 92) of the identified individuals (n= 329) were present in the study area in at least two of the four study years. This information is necessary to gain a better understanding of the ecology and life history characteristics of small cetaceans in the Tafton Strait, and in the development of conservation, education, and habitat protection programs designed to protect these cetaceans from human impacts. This project is part of a long-term ongoing study of the small cetaceans in the Southern Tañon Strait.
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