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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The whistles of Hawaiʻian spinner dolphins (Stenella longirostris) description and geographic variations /

Bazúa Durán, María del Carmen. January 2001 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 2001. / Includes bibliographical references (leaves 372-393). Also available on microfiche.
2

Récupération de biomolécules d’origine aquatique en vue d’une valorisation comme ingrédients fonctionnels dans les domaines alimentaire et pharmaceutique / Recovery of aquatic biomolecules for a valorisation functional ingredients in the food and pharmaceutical fields

Sila, Assaâd 28 February 2015 (has links)
Le présent travail s’inscrit dans le cadre général de la valorisation biotechnologique de produits et coproduits de la pêche. Il a pour principal objectif l’obtention de biomolécules à haute valeur ajoutée à usage alimentaire et nutraceutique à partir des produits et coproduits de la crevette rose du large (Parapenaeus longirostris) et du barbeau (Barbus callensis). Cette étude se divise en deux chapitres distincts : Le premier chapitre est consacré à la mise au point des procédés enzymatique et chimique pour l’obtention de caroténoïdes à partir des coproduits de crevettes. Plus particulièrement, ce chapitre concerne l’extraction, la purification et la caractérisation de l’astaxanthine à partir des coproduits de la crevette rose du large (P. longirostris). Les activités antioxydantes et antiprolifératives in vitro et l’activité antidiabétique in vivo ont été étudiées. Dans le deuxième chapitre, nous présentons l’apport d’une technique analytique pour l’obtention de biopeptides antibactériens et anti-dipeptidyl-peptidase-IV qui repose en général sur l’hydrolyse enzymatique contrôlée de protéines, suivie de méthodes systématiques de fractionnement, de purification et de tests biologiques. Les masses moléculaires ainsi que les séquences des peptides purifiés ont été déterminées par spectrométrie de masse et par spectrométrie de masse en tandem. / This work is part of the overall framework for biotechnology development products and co-products from fishing. Its main objective obtaining biomolecules with high added value for food and nutraceutical from products and coproducts prawn (Parapenaeus longirostris) and barbel (Barbus callensis). This study is divided into two sections: The first chapter is devoted to the development of enzymatic and chemical processes for the production of carotenoids from shrimp co-products. Specifically, this chapter concerns the extraction, purification and characterization of astaxanthin from co-products of the pink shrimp (P. longirostris). Antioxidant activities and antiproliferative in vitro and in vivo antidiabetic activity were studied. In the second chapter, we present the contribution of an analytical technique for obtaining biopeptides antibacterial and anti-dipeptidyl peptidase-IV which is generally based on the controlled enzymatic hydrolysis of proteins, followed by systematic fractionation methods, purification and biological testing. The molecular weights and sequences of the purified peptides were determined by mass spectrometry and tandem mass spectrometry.
3

Valuation of spinner dolphin excursions in Hawaiʻi

Boehle, Katya January 2007 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2007. / Includes bibliographical references (leaves 92-95). / ix, 95 leaves, bound ill. 29 cm
4

Caracterização dos parâmetros acústicos do golfinho-rotador: registro na quebra da plataforma continental sul Brasileira

Moron, Juliana Rodrigues 30 March 2015 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2015-12-08T14:30:37Z No. of bitstreams: 1 julianarodriguesmoron.pdf: 5395147 bytes, checksum: 0f2d0052bd8730bc31eb9bf590e8a739 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2015-12-09T13:42:27Z (GMT) No. of bitstreams: 1 julianarodriguesmoron.pdf: 5395147 bytes, checksum: 0f2d0052bd8730bc31eb9bf590e8a739 (MD5) / Made available in DSpace on 2015-12-09T13:42:27Z (GMT). No. of bitstreams: 1 julianarodriguesmoron.pdf: 5395147 bytes, checksum: 0f2d0052bd8730bc31eb9bf590e8a739 (MD5) Previous issue date: 2015-03-30 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Apesar de investigações bioacústicas de golfinhos-rotadores já terem sido abordadas e descritas na literatura, a região do Oceano Atlântico Sul Ocidental só abrangeu a população do arquipélago de Fernando de Noronha. Portanto, a fim de contribuir para um melhor conhecimento desta espécie cosmopolita, este estudo teve como objetivo descrever os sons através de seus parâmetros acústicos de uma gravação oportunista realizada ao longo da quebra da plataforma continental Brasileira. Um grupo de aproximadamente 400 golfinhos Stenella longirostris foi registrado através de uma matriz de arrasto composta por um hidrofone realizando gravação mono contínua a 96kHz / 24bits. Após uma seleção de 12 minutos a partir do registro, 1.100 assobios foram extraídos e classificados em sete tipos de contornos, juntamente com outras dez variáveis extraídas. Os assobios dos golfinhos-rotadores foram constituídos em sua maioria por contorno ascendente (41,2%). O grupo apresentou ainda assobios com maior índice de modulação de frequência do que já havia sido descrito na literatura, apresentando uma frequência máxima de 26,4 kHz. Apesar da curta duração desses assobios, variando de 0,03 s a 2,56 s (média = 0,67 s), esses valores também foram mais altos do que a maioria dos estudos havia relatado. Apesar de diferenças estatisticamente significativas, a comparação a partir da média dos valores dos parâmetros extraídos apontou que dois estudos anteriores realizados no Oceano Pacífico Norte são mais semelhantes em relação a este estudo. Dessa forma, as possibilidades a partir das comparações discutidas no presente trabalho não só auxiliam a identificar a variabilidade nas emissões de forma a melhorar as classificações de detecção acústica em pesquisas e mitigação de impacto; como também contribuem para a compreensão de populações distintas e / ou espécies distribuídas em diferentes regiões oceânicas. / Spinner dolphins’ bioacoustics have already been described in literature, meanwhile the Western South Atlantic Ocean was only approached inside Fernando de Noronha Archipelago. Therefore, in order to contribute to a better knowledge of this cosmopolitan species, this study aimed to describe the sounds through their acoustic parameters detected during an opportunistic recording carried out at the Brazilian continental shelf break. A group of approximate 400 Stenella longirostris dolphins was recorded through a one-element hydrophone array performing continuous mono recording at 96 kHz/24 bits. After a 12 minutes selection of the record, 1,100 whistles were extracted and classified into seven contours shapes, along with other ten variables extracted. The spinner dolphins whistles was mostly comprised by upsweep (41.2%) contour. The group produced higher pitch frequency modulated whistles than what has been previously described, presenting a maximum frequency of 26.4 kHz. Despite the short whistle durations, ranging from 0.03 s to 2.56 s (mean = 0.67 s), those values were also higher than most of previous works had reported. Despite statistically significant differences, the comparison from the average of the extracted parameters pointed out that two previous studies in the North Pacific Ocean are more similar in relation to this study. Thereby, the possibilities from the comparisons discussed in this paper not only assist in identifying the variability in the emissions in order to improve acoustic detection classifications in research and impact mitigation; but also contribute to the understanding of distinct populations and/or species distributed in different ocean basins.
5

Estudo das vocalizações de golfinhos-rotadores, Stenella longirostris (Cetacea, Delphinidae), no arquipélago de Fernando de Noronha / Study on the vocalizations of spinner dolphins, Stenella longirostris (Cetacea, Delphinidae), from the Fernando de Noronha Archipelago

Camargo, Fernanda Scarano 18 April 2008 (has links)
O conhecimento acerca das vocalizações dos odontocetos é extremamente heterogêneo e concentra-se principalmente nas espécies mantidas em cativeiro. Neste estudo, descrevo quantitativamente parte do repertório vocal dos golfinhos-rotadores, Stenella longirostris, que vivem ao redor do Arquipélago de Fernando de Noronha, subdividido nos seguintes elementos: assobios, grasnidos emitidos na faixa audível e grasnidos emitidos pelos machos durante a corte. Além disso, avaliei a influência tantos dos diferentes sistemas de gravação e análise de dados, quanto da escolha, interpretação e extração de variáveis por diferentes pesquisadores na variabilidade dos assobios e grasnidos emitidos por golfinhosrotadores. Para avaliar a variabilidade dos assobios desta população de golfinhos-rotadores, uma série de análises quantitativas foi conduzida. Nove variáveis foram extraídas de cada contorno de assobio selecionado aleatoriamente. Os valores médios observados foram muito similares àqueles reportados por OSWALD et al. (2003) para golfinhos-rotadores do Oceano Pacífico Tropical Oriental e apresentaram diferença significativa apenas em relação a freqüência máxima dos assobios. Com relação aos grasnidos, amostras foram selecionadas aleatoriamente e destas foram extraídas oito variáveis. Uma série de análises quantitativas foram então conduzidas para avaliar a variabilidade destas emissões. Os valores obtidos para cada uma das variáveis diferiram dos valores previamente reportados para a espécie, mas as razões para esta variação são ainda desconhecidas. Na busca de indícios sobre a função dos grasnidos no comportamento reprodutivo, eu dividi os grasnidos gravados em duas categorias: corte e não-corte. Grasnidos de corte foram aqueles sons gravados na presença de grupos de golfinhos compostos por uma ou duas fêmeas e por vários machos, engajados em comportamento de corte. Grasnidos de não-corte eram todos aqueles gravados em outros comportamentos ou situações. Os resultados obtidos mostraram diferenças significativas entre as duas categorias tanto nas análises univariadas, quanto na Análise Discriminante (AD), pelo menos quanto à duração e ao número de pulsos. Além disso, a AD mostrou que 98% das amostras foram corretamente classificadas nessas categorias. Estes resultados reforçam a idéia de que os grasnidos são usados em contextos sociais, especialmente em situações aflitivas e exaltam a importância da identificação do emissor dos sinais, assim como o uso de equipamentos de gravação de amplo espectro de freqüência. Por fim, realizei uma série de testes para avaliar a metodologia de gravação e análise de sons. Para isso, gravei as emissões utilizando dois sistemas distintos de gravação, ambos com taxa de amostragem de 48 kHz. Além disso, dois pesquisadores diferentes extraíram as variáveis de um mesmo grupo de amostras e os resultados obtidos para cada pesquisador, bem como para cada sistema foram comparados. Os resultados mostraram que, para os assobios, houve diferenças significativas entre as análises de cada pesquisador, quanto à às variáveis freqüência mínima, freqüência final e duração. Ao comparar os resultados obtidos pelos diferentes sistemas de gravação, notei que a duração apresentou diferenças significativas. Quanto aos grasnidos, notei uma diferença significativa no número de amostras de qualidade gravadas por cada um dos sistemas de gravação. Entretanto, as amostras gravadas em ambos os sistemas não apresentaram diferenças significativas em nenhuma das variáveis extraídas, tampouco foram observadas diferenças entre os diferentes pesquisadores. Acredito que o conhecimento gerado aqui contribuirá para uma melhor compreensão dos padrões de variação da espécie e servirá como base para uma série de outros estudos comparativos. / Knowledge on odontocete vocalizations is extremely heterogeneous and centered mainly in those species kept in captivity. In this study, I describe quantitatively part of the vocal repertoire of the spinner dolphin, Stenella longirostris, from Fernando de Noronha Archipelago, off Brazil, subdivided in the following elements: whistles, burst-pulses emitted in the aural range, and burst-pulses emitted by males during courtship. Furthermore, I evaluated the influence of different recording and analysis systems, and the choice, interpretation and extraction of the acoustic variables by different researchers in the variability of whistles and burst-pulses emitted by spinner dolphins. To evaluate the variability of whistles emitted by this population, a series of quantitative analyses was conducted. Nine variables were extracted from each randomly selected whistle contour. The mean values observed were very similar to those reported by OSWALD et al. (2003) for the spinner dolphins from Eastern Tropical Pacific and presented significant differences only in relation to the maximum frequency of the whistles. I extracted eight variables from randomly selected burst-pulsed sound samples. A series of quantitative analyses were conducted to evaluate the variability of these emissions. The values obtained from each of the variables differed from previously data reported for the species, but the reasons to this variation are still unknown. In the search of any signs of burstpulse functions in reproductive behaviors, I divided the recorded burst-pulses in two categories: court and no-court pulses. Court bursts were those sounds recorded in the presence of groups of dolphins composed by one or two females and several males, engaged in courtship behavior. No-court bursts were all those recorded in other behaviors or situations. The results showed significant differences between the two categories in univariate analysis and also in the Discriminant Function Analysis (DFA). The DFA also showed that 98% of the samples were correctly classified in these categories. These results reinforce the idea that burst-pulsed sounds are used in social contexts, specially in afflictive situations, and exalt the importance of identifying the signal emitter, as well as using wide frequency capable recording equipment. Finally, I performed a series of tests to evaluate the methodology of recording and sound analysis. To achieve this, I recorded the sound emissions using two different recording systems, both with sample rate of 48 kHz. Furthermore, two rsearchers extracted the variables of a group of samples, and the results from each researcher and each recording system were compared. Taking into account the whistles, the results showed that there were significant differences between the researchers on duration, minimum and final frequencies recorded. I compared the results obtained by different recording systems and noticed that the sound duration presented significant differences. With respect to burst-pulses, I noticed a significant difference in the number of samples with quality recorded by each of the recording systems. However, the samples recorded in both systems didn\'t show any difference in none of the extracted variables, nor there were observed differences between researchers. I believe that the knowledge produced here will contribute to the comprehension of variation patterns, and will also serve as a basis to further comparative studies.
6

Estudo das vocalizações de golfinhos-rotadores, Stenella longirostris (Cetacea, Delphinidae), no arquipélago de Fernando de Noronha / Study on the vocalizations of spinner dolphins, Stenella longirostris (Cetacea, Delphinidae), from the Fernando de Noronha Archipelago

Fernanda Scarano Camargo 18 April 2008 (has links)
O conhecimento acerca das vocalizações dos odontocetos é extremamente heterogêneo e concentra-se principalmente nas espécies mantidas em cativeiro. Neste estudo, descrevo quantitativamente parte do repertório vocal dos golfinhos-rotadores, Stenella longirostris, que vivem ao redor do Arquipélago de Fernando de Noronha, subdividido nos seguintes elementos: assobios, grasnidos emitidos na faixa audível e grasnidos emitidos pelos machos durante a corte. Além disso, avaliei a influência tantos dos diferentes sistemas de gravação e análise de dados, quanto da escolha, interpretação e extração de variáveis por diferentes pesquisadores na variabilidade dos assobios e grasnidos emitidos por golfinhosrotadores. Para avaliar a variabilidade dos assobios desta população de golfinhos-rotadores, uma série de análises quantitativas foi conduzida. Nove variáveis foram extraídas de cada contorno de assobio selecionado aleatoriamente. Os valores médios observados foram muito similares àqueles reportados por OSWALD et al. (2003) para golfinhos-rotadores do Oceano Pacífico Tropical Oriental e apresentaram diferença significativa apenas em relação a freqüência máxima dos assobios. Com relação aos grasnidos, amostras foram selecionadas aleatoriamente e destas foram extraídas oito variáveis. Uma série de análises quantitativas foram então conduzidas para avaliar a variabilidade destas emissões. Os valores obtidos para cada uma das variáveis diferiram dos valores previamente reportados para a espécie, mas as razões para esta variação são ainda desconhecidas. Na busca de indícios sobre a função dos grasnidos no comportamento reprodutivo, eu dividi os grasnidos gravados em duas categorias: corte e não-corte. Grasnidos de corte foram aqueles sons gravados na presença de grupos de golfinhos compostos por uma ou duas fêmeas e por vários machos, engajados em comportamento de corte. Grasnidos de não-corte eram todos aqueles gravados em outros comportamentos ou situações. Os resultados obtidos mostraram diferenças significativas entre as duas categorias tanto nas análises univariadas, quanto na Análise Discriminante (AD), pelo menos quanto à duração e ao número de pulsos. Além disso, a AD mostrou que 98% das amostras foram corretamente classificadas nessas categorias. Estes resultados reforçam a idéia de que os grasnidos são usados em contextos sociais, especialmente em situações aflitivas e exaltam a importância da identificação do emissor dos sinais, assim como o uso de equipamentos de gravação de amplo espectro de freqüência. Por fim, realizei uma série de testes para avaliar a metodologia de gravação e análise de sons. Para isso, gravei as emissões utilizando dois sistemas distintos de gravação, ambos com taxa de amostragem de 48 kHz. Além disso, dois pesquisadores diferentes extraíram as variáveis de um mesmo grupo de amostras e os resultados obtidos para cada pesquisador, bem como para cada sistema foram comparados. Os resultados mostraram que, para os assobios, houve diferenças significativas entre as análises de cada pesquisador, quanto à às variáveis freqüência mínima, freqüência final e duração. Ao comparar os resultados obtidos pelos diferentes sistemas de gravação, notei que a duração apresentou diferenças significativas. Quanto aos grasnidos, notei uma diferença significativa no número de amostras de qualidade gravadas por cada um dos sistemas de gravação. Entretanto, as amostras gravadas em ambos os sistemas não apresentaram diferenças significativas em nenhuma das variáveis extraídas, tampouco foram observadas diferenças entre os diferentes pesquisadores. Acredito que o conhecimento gerado aqui contribuirá para uma melhor compreensão dos padrões de variação da espécie e servirá como base para uma série de outros estudos comparativos. / Knowledge on odontocete vocalizations is extremely heterogeneous and centered mainly in those species kept in captivity. In this study, I describe quantitatively part of the vocal repertoire of the spinner dolphin, Stenella longirostris, from Fernando de Noronha Archipelago, off Brazil, subdivided in the following elements: whistles, burst-pulses emitted in the aural range, and burst-pulses emitted by males during courtship. Furthermore, I evaluated the influence of different recording and analysis systems, and the choice, interpretation and extraction of the acoustic variables by different researchers in the variability of whistles and burst-pulses emitted by spinner dolphins. To evaluate the variability of whistles emitted by this population, a series of quantitative analyses was conducted. Nine variables were extracted from each randomly selected whistle contour. The mean values observed were very similar to those reported by OSWALD et al. (2003) for the spinner dolphins from Eastern Tropical Pacific and presented significant differences only in relation to the maximum frequency of the whistles. I extracted eight variables from randomly selected burst-pulsed sound samples. A series of quantitative analyses were conducted to evaluate the variability of these emissions. The values obtained from each of the variables differed from previously data reported for the species, but the reasons to this variation are still unknown. In the search of any signs of burstpulse functions in reproductive behaviors, I divided the recorded burst-pulses in two categories: court and no-court pulses. Court bursts were those sounds recorded in the presence of groups of dolphins composed by one or two females and several males, engaged in courtship behavior. No-court bursts were all those recorded in other behaviors or situations. The results showed significant differences between the two categories in univariate analysis and also in the Discriminant Function Analysis (DFA). The DFA also showed that 98% of the samples were correctly classified in these categories. These results reinforce the idea that burst-pulsed sounds are used in social contexts, specially in afflictive situations, and exalt the importance of identifying the signal emitter, as well as using wide frequency capable recording equipment. Finally, I performed a series of tests to evaluate the methodology of recording and sound analysis. To achieve this, I recorded the sound emissions using two different recording systems, both with sample rate of 48 kHz. Furthermore, two rsearchers extracted the variables of a group of samples, and the results from each researcher and each recording system were compared. Taking into account the whistles, the results showed that there were significant differences between the researchers on duration, minimum and final frequencies recorded. I compared the results obtained by different recording systems and noticed that the sound duration presented significant differences. With respect to burst-pulses, I noticed a significant difference in the number of samples with quality recorded by each of the recording systems. However, the samples recorded in both systems didn\'t show any difference in none of the extracted variables, nor there were observed differences between researchers. I believe that the knowledge produced here will contribute to the comprehension of variation patterns, and will also serve as a basis to further comparative studies.
7

Caracteriza??o da frequ?ncia de atividades a?reas do golfinho-rotador, Stenella longirostris (Gray, 1828), na Ba?a dos Golfinhos do Parque Nacional Marinho de Fernando de Noronha

Carli, Rita de C?ssia de 22 March 2012 (has links)
Made available in DSpace on 2014-12-17T15:37:09Z (GMT). No. of bitstreams: 1 RitaCC_DISSERT.pdf: 2507687 bytes, checksum: 4eeca6582506786804976f0255257b80 (MD5) Previous issue date: 2012-03-22 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The aerial activities, leaps and slaps with parts of the body in the surface of water, are part of the behavioral repertoire of several species of cetaceans. Among them, the spinner dolphin, Stenella longirostris, shows greater diversity in such behavior. For the spinner dolphins of Fernando de Noronha, the aerial activities are classified as vertical and horizontal, with eight patterns to be noted (tail slap, head slap, motor boating, partial leap, leap, spin, tail over head and tail over head with spin) discriminated between these categories. Such behaviors can be used as a parameter to identify behavioral changes, as well as patterns of daily and seasonal activity. In this manner, this study aimed to characterize the frequency in performance of such activity while the dolphins were within the Dolphin Bay of Fernando de Noronha, and verify possible daily and seasonal hourly fluctuations on such behaviors. The data analyzed in this study was acquired during the period of January 2006 through December 2010, totaling 1431 days of observation from land set point, with 113027 aerial activities registered, daily average of 72,27 (SD=96,10). During 5478h and 54 min of observation the horizontal aerial activity was the most observed and rotation was the most executed pattern. Greater frequency of execution of aerial activity was observed in adults, but for both adults and calves, was observed a predominance of horizontal activities, with spin being the pattern most executed. Positive correlation was observed between the amount of aerial activity performed and the number of animals inside the Bay. Hourly daily fluctuation was observed in the expression of aerial activities by spinner dolphins, and was observed a peak of activity between 8h and 8h59min for the overall frequency relative of aerial activities, as well as for the categories and patterns. Seasonal differences were observed between the rainy and dry season with the greater amount of activity being observed during the rainy season. Nevertheless, the same profile of frequency relative of aerial activity was observed in both seasons with the peak amount being during the same period. When discriminated the aerial activities in categories and patterns, for both seasons, there was a similar pattern of hourly fluctuation; for most of parameters, higher frequency relative of execution of aerial activity remain between 8h and 8h59min / As atividades a?reas, saltos e batidas com partes do corpo na superf?cie da ?gua, comp?em parte do repert?rio comportamental de diversas esp?cies de cet?ceos. Dentre elas, acredita-se que o golfinho-rotador, Stenella longirostris, seja a esp?cie que apresenta maior agilidade em tais comportamentos. Para os golfinhos-rotadores de Fernando de Noronha, as atividades a?reas s?o categorizadas em atividades a?reas verticais e horizontais, sendo oito (batida de cauda, batida de cabe?a, motor de popa, ca?da, salto, rota??o, invers?o e pirueta) os padr?es discriminados entre essas classes. Tais comportamentos podem ser usados como par?metros para identificar altera??es comportamentais, bem como os padr?es de atividade di?ria e sazonais. Desta forma, o presente estudo teve por objetivo caracterizar a frequ?ncia de execu??o de atividades a?reas no decorrer do per?odo em que os golfinhos-rotadores permanecem dentro da Ba?a dos Golfinhos de Fernando de Noronha, bem como verificar a exist?ncia de poss?veis flutua??es hor?rias di?rias e sazonais na exibi??o de tais comportamentos. Para isso, foram analisados dados que compreendem o per?odo entre janeiro de 2006 a dezembro de 2010, totalizando 1.431 dias de observa??o em ponto fixo, sendo registradas 113.027 atividades a?reas, m?dia di?ria de 72,27 (DP=96,10). Nas 5.478 horas e 54 minutos de observa??o, as atividades a?reas horizontais foram observadas em maior frequ?ncia, sendo a rota??o o padr?o mais executado. Maior frequ?ncia de execu??o das atividades a?reas foi observada em indiv?duos adultos, mas tanto para adultos quanto para filhotes, observou-se predom?nio das atividades horizontais, com a rota??o sendo o padr?o mais executado. Correla??o positiva foi observada entre a quantidade de atividades a?reas executadas e o n?mero de animais dentro da Ba?a. Flutua??o hor?ria di?ria foi observada na express?o das atividades a?reas pelos golfinhos-rotadores, sendo observado maior pico de atividade no hor?rio entre 8h e 8h59min, tanto para a frequ?ncia relativa total de atividades a?reas, quanto para as classes e os padr?es. Diferen?as entre as esta??es clim?ticas seca e chuvosa foram observadas, com maior registro de atividade a?rea durante o per?odo de chuvas. Entretanto, o perfil de distribui??o da frequ?ncia relativa de atividades a?reas se assemelha para ambas as esta??es, mantendo o hor?rio de maior pico de atividade. Quando discriminadas as atividades a?reas nas classes e nos padr?es considerados, para ambas as esta??es observaram-se padr?o de flutua??o hor?ria semelhante; para a maioria dos par?metros analisados, maior frequ?ncia relativa de execu??o das atividades a?reas se mant?m entre 8h e 8h59min
8

The Ecological Influence of the Non-Indigenous Zooplankter <i>Eubosmina coregoni</i> in Lake Ecosystems

Kirkpatrick, Heather 08 April 2011 (has links)
No description available.
9

Réponses d'une population aux forçages environnementaux et anthropiques : le suivi à long terme de la crevette Palaemon Longirostris de l'Estuaire de la Gironde (1979-2007)

Béguer, Mélanie 27 November 2009 (has links)
La population de la crevette blanche Palaemon longirostris, espèce résidente des estuaires faisant l’objet d’une pêche traditionnelle, est soumise à des forçages environnementaux (fluctuations naturelles du milieu, modifications du régime hydro-climatique de l’estuaire en lien avec le changement climatique) et anthropiques importants (aspiration dans les circuits du CNPE -Centre Nucléaire de production d’Electricité du Blayais-, pêche ciblée, pollutions etc.). Dans ce contexte et sur la base d’un suivi mensuel, réalisé depuis 1979, complété par des échantillonnages en 2007, cette thèse montre que cette population répond fortement aux changements environnementaux abiotiques et anthropiques. Ainsi, d’importantes fluctuations spatio-temporelles des abondances sont mises en évidence à diverses échelles temporelles, spatiales et biologiques. L’analyse de la série à long terme montre des fortes oscillations interannuelles régulières (période 5/10 ans) en partie liées aux facteurs environnementaux et aux variations du recrutement. Une diminution de l’abondance globale, ainsi qu’un déplacement vers l’amont de cette population, sont également constatés. Ce déclin est attribué aux fortes variations et nombreuses modifications des traits de vie de l’espèce –reproduction, -croissance, -mortalité, démontrées au cours de l’étude. La présence de déformations de l’exosquelette, étudiée aussi via un élevage de plusieurs mois, révèle par ailleurs, de forts impacts négatifs à l’échelle individuelle (mortalité). De plus, des simulations réalisées à partir d’un modèle matriciel de dynamique de population élaboré durant l’étude, montrent la synergie des pressions anthropiques par prélèvements (CNPE, pêche) et des forçages environnementaux, ainsi que l’importance des processus de déplacement dans le fonctionnement de cette population. Cette étude démontre finalement l’intérêt que revêt cette population et plus largement les populations de crevettes estuariennes, pour l’étude du fonctionnement et du diagnostic de l’état des écosystèmes estuariens. De nouvelles métriques originales sont proposées, lesquelles ouvrent vers la voie vers de nouveaux indicateurs. / The white shrimp, Palaemon longirostris, is an estuarine species and an important fishing resource. This species therefore encounters an important environmental forcing (natural fluctuations of the environment, modifications of the hydro-climatic regime of the estuary associated with the climate change) and an anthropological forcing (drawing up by the circuits of the CNPE - Nuclear center of electricity production of Blayais-, targeted fishing, pollutions etc.). In this context and on the basis of a monthly survey in place since 1979 and completed in 2007, this study shows that this population is strongly influenced by environmental and anthropological changes. Important spatio-temporal variations in the shrimp abundance are highlighted at different temporal, spatial and biological scales. A long-term analysis underlines strong regular interannual oscillations (5/10-year period) partially linked with environmental factors and recruitment variations. A decrease in the global abundance and a movement of this population towards the upstream part of the estuary are also displayed. In this study, the decline is attributed to strong variations and numerous modifications in the life history traits of the species - reproduction, - growth, - mortality. The presence of exoskeletal deformities, alternatively studied via a rearing of several months, reveals strong negative impacts at the individual scale (mortality). Furthermore, simulations based on a population-matrix model, developed during the study, show the synergy of the anthropological pressure by capture (CNPE, fishing) and the environmental forcing, as well as the importance of movement processes in the population dynamics. This study finally demonstrates the interest of this population, and more widely of the estuarine shrimp populations, in the understanding of the functioning and the diagnosis of the estuarine ecosystem state. New original metrics are proposed, opening the way towards new indicators.
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Abundance of Spinner Dolpin (Stenella longirostris) in the Southern Tanon Strait, Philippines 2004-2007

Stronach, 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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