Este trabalho tem por objetivo investigar a interação da pescaria de espera e as capturas acidentais de Pontoporia blainvillei, bem como a implicação da atividade na conservação da espécie. Para tanto, foram descritas e analisadas a atividade pesqueira, avaliadas as capturas acidentais, estimadas a mortalidade e estudados alguns aspectos da estrutura populacional, como a estimativa da idade, do crescimento e de parâmetros de algumas variáveis reprodutivas das toninhas acidentalmente capturadas no litoral do Estado de São Paulo. O monitoramento sistemático da frota pesqueira do município da Praia Grande durante o período de julho de 1999 a dezembro de 2008 permitiu uma avaliação temporal das capturas acidentais e dos índices de captura por unidade de esforço de pesca. Cinco tipos de redes de espera e um tipo de rede de arrastão de praia foram utilizados pela frota pesqueira da Praia Grande, sendo observadas capturas em quatro tipos de redes de espera. Um total de 91 toninhas foram acidentalmente capturadas e os valores de CPUE indicam que as redes de superfície boeira e a rede demersal fundo grossa são as responsáveis pelos maiores valores de captura nos meses de outono e inverno. Ao longo de todo o litoral paulista foi verificado o uso de redes de emalhe de espera em áreas costeiras, totalizando cerca de 1.192 embarcações operando redes de emalhe. A partir do monitoramento sistemático de quatro comunidades pesqueiras estimou-se um esforço de pesca total para a frota de emalhe do Estado de São Paulo em 4.684.981 km x dia de pesca, o qual foi multiplicado pela captura por unidade de esforço de pesca média (0,00008 toninhas/km x dia de pesca) resultando em uma estimativa de mortalidade de 372 toninhas para o período de junho de 2004 a abril de 2005. As idades estimadas dos animais capturados variaram de 0 a 14 anos, sendo que 80,0 % possuíam idade entre 0 e 3 anos. As fêmeas tiveram distribuição de idade 0 a 7 anos e os machos de 0 a 14 anos. O comprimento máximo assintótico estimado pelo modelo de von Bertalanffy ajustado aos dados de comprimento total e idade foi de 117,5 cm para machos e 135,6 cm para fêmeas 135,6 cm. O valor da taxa de crescimento estimado para os machos (0,859) foi superior ao das fêmeas (0,779). Não foi constatada diferença significativa entre comprimento, peso e largura entre as gônadas do mesmo animal, confirmado a hipótese de simetria. Os valores médios das medidas macroscópicas das gônadas, assim como o Índice de Maturidade Testicular (IMT) e Ovariano (IMO) foram significativamente diferentes entre indivíduos maduros, púberes e imaturos e apresentaram nítido aumento dos valores para os indivíduos maduros, demonstrando o aumento em tamanho e peso das gônadas com a chegada da maturidade gonadal. A análise microscópica de 45 testículos revelou que 33,3% dos machos eram imaturos, 15,6% púberes e 51,1% maduros. A análise microscópica dos ovários de 42 fêmeas resultou uma proporção de 54,8% fêmeas imaturas, 4,8% púberes e 40,5% maduras. Do total de fêmeas maduras capturadas nove estavam prenhas e apresentaram corpo lúteo de gravidez de grande dimensão. O número máximo de corpos albicans e lúteos observados nos ovários das fêmeas maduras foi três, ocorrendo 61,9% no ovário esquerdo. O comprimento médio e a idade média de maturidade para os machos foram estimados em 103,6 e 107,83 cm e 1,31 e 1,48 anos, respectivamente e para as fêmeas em 119 cm e 1,2 a 1,83 anos, dependo do método utilizado. O tempo de gestação estimado 10,22 meses, taxa de prenhez anual de 0,56, comprimento de nascimento de 72,05 cm, taxa de crescimento fetal de 0,27 cm/dia e o intervalo reprodutivo de 1,77 anos. Os resultados obtidos para o litoral do estado de São Paulo indicam que a pescaria de emalhe incide principalmente nos indivíduos imaturos de ambos os sexos, com 0 a 2 anos de idade, mas que um percentual significativo de adultos maduros também vem sendo capturados. Além disso, foi constatado que não há padrão latitudinal das variáveis estudadas. / The scope of this study is to investigate the interactions of gillnet fishing and the accidental captures of the Pontoporia blainvillei, as well as the implications of this activity in species conservation. Therefore, fishing activities are described and analyzed, accidental captures are evaluated, mortality is estimated and some aspects of population structure are studied, such as growth and age estimates, besides criteria estimates of reproduction variables in franciscana dolphin accidentally caught on the coast of the State of São Paulo. Continuous monitoring of the fishing boats in Praia Grande County, from July 1999 to December 2008 allowed both the chronological evaluation of accidental catching and capture per unit effort. Five different types of gillnets and one of trawl net for shallow areas were used by the fishing boats in Praia Grande, of which four types of gillnets registered catching. A total number of 91 franciscana dolphins were accidentally captured and the values of catch per unit effort (CPUE) indicate that \"boeira\" surface nets and \"bottom thick\" demersal nets are responsible for the highest capture numbers during autumn and winter time. The use of drift nets was observed along the coast of the São Paulo State where a total of 1,192 boats have used such nets. Through the systematic monitoring of four fishing communities, the total fishing effort concerning drift nets, in the State of São Paulo, was 4,684,981 km per fishing day. This value was then multiplied by the catch per unit of average fishing (0.00008 Franciscana dolphins/km x fishing day), which resulted in an estimate mortality of 372 dolphins between June 2004 and April 2005. Estimated age of captured animals varied from 0 to 14 years, 80.0% ranged between 0 and 3 years. Age distribution among female dolphins was from 0 to 7 years, while among male dolphins it was from 0 to 14 years. The maximum asymptotic lenght, estimated according to the von Bertalanffy model and adjusted to the length and age data, was of 117.5 cm for males and 135.6 cm for females. The estimated growth rate for males (0.859) was higher than for females (0.779). No significant difference regarding length, weight, and width between the gonads of the same animal was noticed, confirming the symmetry hypothesis. The average values of the gonads macroscopic measures, as well as both the Testicular (TIM) and Ovarian (OIM) Index of Maturity were significantly different among mature, pubescent and immature individuals. There was a clear increase in value for mature individuals, which demonstrates the gonads size and weight increase as they reach maturity. Microscopic analysis of 45 testicles showed that 33.3% of males were immature, 15.6% pubescent, and 51.1% mature. Microscopic analysis of 42 female ovaries showed that 54.8% of females were immature, 4.8% pubescent, and 40.5% mature. Nine out of the total mature females captured were pregnant and presented a pregnancy corpus luteum of greater size. The maximum corpus albicans and corpus luteum numbers observed in mature female ovaries was three - 61.9% occurring in the left ovary. Both average length and average sexual maturity age for male individuals were estimated between 103.6 107.83 cm and 1.31 1.48 years, respectively. For female individuals these numbers were 119 cm and 1.2 1.83 years, depending on the method used. The estimated pregnancy period was 10.22 months; the annual pregnancy rate was 0.56; the birth length was 72.05 cm; the fetal growth rate was 0.27 cm/day, and the reproduction interval was 1.77 year. The results obtained in the State of São Paulo indicate that drift nets affect mainly immature individuals of both sexes, from 0 to 2 years old. However, a significant percentage of mature adults have also been captured. Besides, no latitude pattern in the variables studied was confirmed.

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-10-25T13:39:22Z No. of bitstreams: 1 2015 - Carine Cristina Gon?alves Galv?o.pdf: 2315391 bytes, checksum: 154e1cdd3a9bb2de5fd18d636c4a6543 (MD5) / Made available in DSpace on 2016-10-25T13:39:22Z (GMT). No. of bitstreams: 1 2015 - Carine Cristina Gon?alves Galv?o.pdf: 2315391 bytes, checksum: 154e1cdd3a9bb2de5fd18d636c4a6543 (MD5) Previous issue date: 2015-02-24 / Funda??o Carlos Chagas Filho de Amparo ? Pesquisa do Estado do RJ - FAPERJ / Some animals have extremely complex relationships including the formation of matriarchal societies, alliances and communities, specific long-term relationships, and formation of flexible groups, such as dolphins. Ilha Grande Bay, along with Sepetiba Bay, have the largest population of Sotalia guianensis throughout its distribution, with about 1311 individuals in the first one, and 1043 individuals in the second, where it has been registered groups with up to 450 individuals. This study aimed to analyze the social organization of the mothers of S. guianensis from Ilha Grande Bay. The mothers were considered those dolphins observed at least five times in high proximity of a calf; all its associates were also classified as females and included in the analysis. The analysis of these mothers? social structure was carried out in SOCPROG? software (2.5 version) using a Half Weight Index (HWI). It was performed an analysis of the community division by modularity which indicated that individuals do not form independent clusters. A Monte Carlo permutation test was done and showed the presence of preferred associations among some dyads. Finally, a temporal analysis was performed with the use of mathematical models fitted to the Lagged Association Rate to try to explain how associations behave over time. The social structure of the 25 mothers identified in Ilha Grande Bay seems to be poorly differentiated, forming a large social network with weak associations between dyads, and following a fission-fusion dynamics. There was no statistical difference in the associations between and within classes (mothers X females). This work is a contribution to the understanding of the species? social dynamics, which are still poorly known, and highlights the need for more research in the area. / Alguns animais possuem rela??es extremamente complexas, incluindo forma??o de sociedades matriarcais, alian?as e comunidades, relacionamentos espec?ficos de longa dura??o, e forma??o de grupos flex?veis, como ? o caso dos golfinhos. A Ba?a da Ilha Grande, juntamente com a Ba?a de Sepetiba, possui a maior popula??o de Sotalia guianensis em toda a sua distribui??o, com estimativa de 1311 indiv?duos na primeira, e 1043 indiv?duos na segunda, onde j? foram registrados grupos com at? 450 indiv?duos. Este trabalho teve como objetivo analisar a organiza??o social das m?es de S. guianensis da Ba?a da Ilha Grande. Foram consideradas m?es aqueles golfinhos vistos no m?nimo cinco vezes em forte proximidade de um filhote, e todos os seus associados foram classificados como f?meas e inclu?dos nas an?lises. A an?lise da estrutura social destas m?es foi feito no programa SOCPROG? (vers?o 2.5) atrav?s do ?ndice Half Weight (HWI). Foi feita uma an?lise de divis?o de comunidades por modularidade que indicou que os indiv?duos n?o formam agrega??es independentes. Um teste de permuta??o de Monte Carlo foi realizado e mostrou a presen?a de associa??es preferidas entre algumas duplas. Por fim, uma an?lise temporal foi realizada com a utiliza??o de modelos matem?ticos ajustados ? Lagged Association Rate para tentar explicar como as associa??es se comportam no decorrer do tempo. A estrutura social das 25 m?es identificadas de S. guianensis na Ba?a da Ilha Grande se mostrou pouco diferenciada, formando uma grande rede com fracas associa??es entre duplas, seguindo uma din?mica de fiss?o-fus?o. N?o houve diferen?a estat?stica nas associa??es entre e dentro das classes (m?es X f?meas). Este trabalho ? uma contribui??o para o entendimento das din?micas sociais da esp?cie, que ainda s?o pouco conhecidas, e ressalta a necessidade de mais pesquisas na ?rea.

Made available in DSpace on 2016-04-28T20:38:44Z (GMT). No. of bitstreams: 1 Gilzete Passos Magalhaes.pdf: 1085410 bytes, checksum: 544367ba9bd174ca6373ecbdf047c3e9 (MD5) Previous issue date: 2013-10-11 / Analytical Psychology believes that psychological aspects are also expressed through myths, folklore, fairy tales and historical-cultural processes. Seeking to grasp these phenomena, it promotes dialogues with various areas of knowledge. This research aims to understand The River Dolphin legend under the symbolic viewpoint and its significance to masculinity, femininity and gender relations in some groups of riverside communities in the Amazon Region. For this study, we adopted the qualitative method of analysis by means of a documentary research from which we selected narratives about this folklorical character in literature, music, film, and the testimonials of people from coastal communities compiled by scholars in History, Anthropology, Music and Analytical Psychology. The chosen material was submitted to the archetypal symbolic processing (PENNA, 2009) that proposes the understanding of the symbol meaning, and from this research stage onwards we identified three thematic groups for analysis: the symbolism of nature in The River Dolphin legend, the dynamics of the psyche in gender relations in riverine communities, and The River Dolphin and its reflection in the myths. The results of the study suggest the influence of geographical and cultural aspects in the riverine imagery, also indicating that The River Dolphin legend deals with themes that could lead to defensive separation of male and female in the constitution of genres and their relationship / A Psicologia Analítica considera que aspectos psíquicos se expressam também por meio de mitos, folclore, contos e processos histórico-culturais e, na busca da compreensão desses fenômenos, promove diálogos com diversas áreas do conhecimento. Esta pesquisa tem como objetivo compreender a lenda O Boto sob o ponto de vista simbólico e o seu significado para a masculinidade, a feminilidade e a relação de gênero em alguns grupos de comunidades ribeirinhas da Amazônia. Para a realização deste estudo, adotamos o método de análise qualitativa, por meio de pesquisa documental em que selecionamos narrativas sobre o personagem do folclore O Boto presentes na literatura, na música, no cinema e nos depoimentos de pessoas de comunidades ribeirinhas compilados por estudiosos da História, Antropologia, Música e Psicologia Analítica. O material eleito foi submetido ao processamento simbólico arquetípico (PENNA, 2009) que propõe a compreensão do significado do símbolo e, a partir dessa etapa da pesquisa, foram identificados três grupos temáticos para análise: o simbolismo da natureza na lenda O Boto, a dinâmica da psique nas relações de gênero nas comunidades ribeirinhas, e O Boto e seu reflexo nos mitos. Os resultados deste estudo sugerem a influência dos aspectos geográficos e culturais no imaginário ribeirinho e que a lenda do Boto aponta temas que podem levar à separação defensiva do masculino e feminino na constituição dos gêneros e em sua relação

Este trabalho tem por objetivo investigar a interação da pescaria de espera e as capturas acidentais de Pontoporia blainvillei, bem como a implicação da atividade na conservação da espécie. Para tanto, foram descritas e analisadas a atividade pesqueira, avaliadas as capturas acidentais, estimadas a mortalidade e estudados alguns aspectos da estrutura populacional, como a estimativa da idade, do crescimento e de parâmetros de algumas variáveis reprodutivas das toninhas acidentalmente capturadas no litoral do Estado de São Paulo. O monitoramento sistemático da frota pesqueira do município da Praia Grande durante o período de julho de 1999 a dezembro de 2008 permitiu uma avaliação temporal das capturas acidentais e dos índices de captura por unidade de esforço de pesca. Cinco tipos de redes de espera e um tipo de rede de arrastão de praia foram utilizados pela frota pesqueira da Praia Grande, sendo observadas capturas em quatro tipos de redes de espera. Um total de 91 toninhas foram acidentalmente capturadas e os valores de CPUE indicam que as redes de superfície boeira e a rede demersal fundo grossa são as responsáveis pelos maiores valores de captura nos meses de outono e inverno. Ao longo de todo o litoral paulista foi verificado o uso de redes de emalhe de espera em áreas costeiras, totalizando cerca de 1.192 embarcações operando redes de emalhe. A partir do monitoramento sistemático de quatro comunidades pesqueiras estimou-se um esforço de pesca total para a frota de emalhe do Estado de São Paulo em 4.684.981 km x dia de pesca, o qual foi multiplicado pela captura por unidade de esforço de pesca média (0,00008 toninhas/km x dia de pesca) resultando em uma estimativa de mortalidade de 372 toninhas para o período de junho de 2004 a abril de 2005. As idades estimadas dos animais capturados variaram de 0 a 14 anos, sendo que 80,0 % possuíam idade entre 0 e 3 anos. As fêmeas tiveram distribuição de idade 0 a 7 anos e os machos de 0 a 14 anos. O comprimento máximo assintótico estimado pelo modelo de von Bertalanffy ajustado aos dados de comprimento total e idade foi de 117,5 cm para machos e 135,6 cm para fêmeas 135,6 cm. O valor da taxa de crescimento estimado para os machos (0,859) foi superior ao das fêmeas (0,779). Não foi constatada diferença significativa entre comprimento, peso e largura entre as gônadas do mesmo animal, confirmado a hipótese de simetria. Os valores médios das medidas macroscópicas das gônadas, assim como o Índice de Maturidade Testicular (IMT) e Ovariano (IMO) foram significativamente diferentes entre indivíduos maduros, púberes e imaturos e apresentaram nítido aumento dos valores para os indivíduos maduros, demonstrando o aumento em tamanho e peso das gônadas com a chegada da maturidade gonadal. A análise microscópica de 45 testículos revelou que 33,3% dos machos eram imaturos, 15,6% púberes e 51,1% maduros. A análise microscópica dos ovários de 42 fêmeas resultou uma proporção de 54,8% fêmeas imaturas, 4,8% púberes e 40,5% maduras. Do total de fêmeas maduras capturadas nove estavam prenhas e apresentaram corpo lúteo de gravidez de grande dimensão. O número máximo de corpos albicans e lúteos observados nos ovários das fêmeas maduras foi três, ocorrendo 61,9% no ovário esquerdo. O comprimento médio e a idade média de maturidade para os machos foram estimados em 103,6 e 107,83 cm e 1,31 e 1,48 anos, respectivamente e para as fêmeas em 119 cm e 1,2 a 1,83 anos, dependo do método utilizado. O tempo de gestação estimado 10,22 meses, taxa de prenhez anual de 0,56, comprimento de nascimento de 72,05 cm, taxa de crescimento fetal de 0,27 cm/dia e o intervalo reprodutivo de 1,77 anos. Os resultados obtidos para o litoral do estado de São Paulo indicam que a pescaria de emalhe incide principalmente nos indivíduos imaturos de ambos os sexos, com 0 a 2 anos de idade, mas que um percentual significativo de adultos maduros também vem sendo capturados. Além disso, foi constatado que não há padrão latitudinal das variáveis estudadas. / The scope of this study is to investigate the interactions of gillnet fishing and the accidental captures of the Pontoporia blainvillei, as well as the implications of this activity in species conservation. Therefore, fishing activities are described and analyzed, accidental captures are evaluated, mortality is estimated and some aspects of population structure are studied, such as growth and age estimates, besides criteria estimates of reproduction variables in franciscana dolphin accidentally caught on the coast of the State of São Paulo. Continuous monitoring of the fishing boats in Praia Grande County, from July 1999 to December 2008 allowed both the chronological evaluation of accidental catching and capture per unit effort. Five different types of gillnets and one of trawl net for shallow areas were used by the fishing boats in Praia Grande, of which four types of gillnets registered catching. A total number of 91 franciscana dolphins were accidentally captured and the values of catch per unit effort (CPUE) indicate that \"boeira\" surface nets and \"bottom thick\" demersal nets are responsible for the highest capture numbers during autumn and winter time. The use of drift nets was observed along the coast of the São Paulo State where a total of 1,192 boats have used such nets. Through the systematic monitoring of four fishing communities, the total fishing effort concerning drift nets, in the State of São Paulo, was 4,684,981 km per fishing day. This value was then multiplied by the catch per unit of average fishing (0.00008 Franciscana dolphins/km x fishing day), which resulted in an estimate mortality of 372 dolphins between June 2004 and April 2005. Estimated age of captured animals varied from 0 to 14 years, 80.0% ranged between 0 and 3 years. Age distribution among female dolphins was from 0 to 7 years, while among male dolphins it was from 0 to 14 years. The maximum asymptotic lenght, estimated according to the von Bertalanffy model and adjusted to the length and age data, was of 117.5 cm for males and 135.6 cm for females. The estimated growth rate for males (0.859) was higher than for females (0.779). No significant difference regarding length, weight, and width between the gonads of the same animal was noticed, confirming the symmetry hypothesis. The average values of the gonads macroscopic measures, as well as both the Testicular (TIM) and Ovarian (OIM) Index of Maturity were significantly different among mature, pubescent and immature individuals. There was a clear increase in value for mature individuals, which demonstrates the gonads size and weight increase as they reach maturity. Microscopic analysis of 45 testicles showed that 33.3% of males were immature, 15.6% pubescent, and 51.1% mature. Microscopic analysis of 42 female ovaries showed that 54.8% of females were immature, 4.8% pubescent, and 40.5% mature. Nine out of the total mature females captured were pregnant and presented a pregnancy corpus luteum of greater size. The maximum corpus albicans and corpus luteum numbers observed in mature female ovaries was three - 61.9% occurring in the left ovary. Both average length and average sexual maturity age for male individuals were estimated between 103.6 107.83 cm and 1.31 1.48 years, respectively. For female individuals these numbers were 119 cm and 1.2 1.83 years, depending on the method used. The estimated pregnancy period was 10.22 months; the annual pregnancy rate was 0.56; the birth length was 72.05 cm; the fetal growth rate was 0.27 cm/day, and the reproduction interval was 1.77 year. The results obtained in the State of São Paulo indicate that drift nets affect mainly immature individuals of both sexes, from 0 to 2 years old. However, a significant percentage of mature adults have also been captured. Besides, no latitude pattern in the variables studied was confirmed.

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.

Vertebrate evolution has resulted in a diversity of feeding mechanisms. Cetaceans are secondarily derived tetrapods that have returned to a marine habitat. As a result, they display feeding modes that have converged with more basal aquatic vertebrates, but display a diversity of new solutions and adaptations. To begin to explore the diversity of feeding adaptations among odontocetes, kinematics of feeding modes and feeding adaptations for belugas (Delphinapterus leucas), Pacific white-sided dolphins (Lagenorhynchus obliquidens), and long-finned pilot whales (Globicephala melas) were characterized. In addition, direct measurements of intraoral pressure were collected to determine maximum suction performance. Characters from these analyses were combined with data for other odontocetes, and were mapped onto a phylogeny of Odontoceti to begin to explore where changes in feeding modes took place. Feeding modes were diverse in belugas, Pacific white-sided dolphins, and pilot whales and included suction, ram, and a combination of both. In general, four phases were observed: (I) preparatory, (II) jaw opening, (III) gular depression, and (IV) jaw closing. Suction was a large component of the prey capture method in belugas and subambient pressures in excess of 100 kPa were generated. Belugas were also capable of lateral lip gape occlusion and anterior lip pursing to form a small anterior aperture. Pacific whitesided dolphins relied on ram to capture prey. However, some degree of pursing and resultant subambient pressure was observed that was likely used to compensate for high ram speeds or for prey manipulation and transport to the esophagus. Pilot whales were more similar to belugas in kinematics, but maintained high approach velocities and did not generate significant suction pressures; suction and ram were used in combination. Belugas and pilot whales appeared to employ hyolingual depression as a primary suction generation mechanism, whereas Pacific white-sided dolphins relied on fast jaw opening. Ancestral state reconstructions indicated that suction feeding capability evolved independently at least six times within Odontoceti. These results indicate the diversity of feeding behaviors in odontocetes and provide directives for future studies on the diversity of feeding in secondarily aquatic mammals.

Bottlenose dolphins (Tursiops truncatus) and other odontocete cetaceans rely on sound for communication, navigation, and foraging. Therefore, hearing is one of their primary sensory modalities. Both natural and anthropogenic noise in the marine environment could mask the ability of free-ranging dolphins to detect sounds, and chronic noise exposure could cause permanent hearing losses. In addition, several mass strandings of odontocete cetaceans, especially beaked whales, have been correlated with military exercises involving mid-frequency sonar, highlighting unknowns regarding hearing sensitivity in these animals.Auditory evoked potential (AEP) methods are attractive over traditional behavioral methods for measuring the hearing of marine mammals because they allow rapid assessments of hearing sensitivity and can be used on untrained animals. The goals of this study were to 1.) investigate the differences among underwater AEP, in-air AEP, and underwater behavioral heari ng measurements using two captive bottlenose dolphins, 2.) investigate the hearing abilities of a population of free-ranging bottlenose dolphins in Sarasota Bay, Florida, using AEP techniques, and 3.) report the hearing abilities of a stranded juvenile beaked whale (Mesoplodon europaeus) measured using AEP techniques.For the two captive dolphins, there was generally good agreement among the hearing thresholds determined by the three test methods at frequencies above 20 kHz. At 10 and 20 kHz, in-air AEP audiograms were substantially higher (about 15 dB) than underwater behavioral and underwater AEP audiograms.For the free-ranging dolphins of Sarasota Bay, Florida, there was considerable individual variation, up to 80 dB between individuals, in hearing abilities. There was no relationship between age, gender, or PCB load and hearing sensitivities. Hearing measured in a 52-year-old captive-born bottlenose dolphin showed similar hearing thresholds to the Sarasota dolphins up to 80 kHz, but exhibited a 50 dB drop in sensitivity at 120 kHz.Finally, the beaked whale was most sensitive to high frequency signals between 40 and 80 kHz, but produced smaller evoked potentials to 5 kHz, the lowest frequency tested. The beaked whale hearing range and sensitivity were similar to other odontocetes that have been measured.

In conservation ecology, abundance estimates are an important factor from which management decisions are based. Methods to estimate abundance of cetaceans from visual detections are largely developed, whereas parallel methods based on passive acoustic detections are still in their infancy. To estimate the abundance of cetacean species using acoustic detection data, it is first necessary to correctly identify the species that are detected. The current automatic PAMGUARD Whistle Classifier used to automatically identify whistle detection of cetacean species is modified with the objective to facilitate the use of these detections to estimate cetacean abundance. Given the variability of cetacean sounds within and between species, developing an automated species classifier with a 100% correct classification probability for any species is unfeasible. However, through the examples of two case studies it is shown that large and high quality datasets with which to develop these automatic classifiers increase the probability of creating reliable classifiers with low and precise misclassification probability. Given that misclassification is unavoidable, it is necessary to consider the effect of misclassified detections on the number of observed acoustic calls detected and thus on abundance estimates, and to develop robust methods to cope with these misclassifications. Through both heuristic and Bayesian approaches it is demonstrated that if misclassification probabilities are known or estimated precisely, it is possible to estimate the true number of detected calls accurately and precisely. However, misclassification and uncertainty increase the variance of the estimates. If the true numbers of detections from different species are similar, then a small amount of misclassification between species and a small amount of uncertainty in the probabilities of misclassification does not have a detrimental effect on the overall variance and bias of the estimate. However, if there is a difference in the encounter rate between species calls associated with a large amount of uncertainty in the probabilities of misclassification, then the variance of the estimates becomes larger and the bias increases; this in return increases the variance and the bias of the final abundance estimate. This study despite not bringing perfect results highlights for the first time the importance of dealing with the problem of species misclassification for cetacean if acoustic detections are to be used to estimate abundance of cetaceans.

published_or_final_version / Ecology and Biodiversity / Doctoral / Doctor of Philosophy

Within-population behavioural variation can greatly affect the ecology of a species and the outcome of evolutionary processes. This study aimed to determine how variable sperm whale social and vocal behaviour is between both individuals and their social units. The population of whales off Dominica is small and isolated from communities in neighbouring waters. Female and immature whales live together in social units containing about 7 animals. I analysed their social relationships and their ‘coda’ communication signals using an unparalleled dataset of social and vocal interactions at the level of the individual. Within units, calves were significant nodes in their social unit’s network, and thus I provide quantitative support for the hypothesis that communal calf care acts as the primary evolutionary driver for group formation in this species. Social relationships within and between units were diverse, while the spatial spread of individuals within units and their travel speeds were similar among all of the units. I identified long-term patterns of association between units consistent over decadal time scales. Social units had characteristic vocal repertoires, but all were dominated by the ‘1+1+3’ and ‘5R’ coda types. Differences between units resulted from some units using specific 4-click coda types. Units and individuals used different accents on their ‘5R’ codas, but the ‘1+1+3’ coda was stereotyped across all individuals and units studied. The repertoires of different units were as similar as units within vocal clans in the Pacific. My results support the hypothesis that the ‘5R’ coda may function in individual identification. The stability of the ‘1+1+3’ coda may be the result of selection for a marker of clan membership. Individual repertoires differed consistently across years; and contrary to an existing hypothesis, new mothers did not vary their repertoire to be more distinct after giving birth. However, calves did use a class-specific ‘3+1’ coda. In summary, sperm whale social and vocal behaviour vary between individuals and among units. Variation in the social and vocal behaviour of female sperm whales results from a trade-off between individuality and conformity within units and clans.