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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

Age and growth of bony flyingfish (Hirundichthys oxycephalus) off the eastern Taiwan through otolith examination and it¡¦s implication in fisheries management

Lin, Chung-hui 27 July 2010 (has links)
¡@Bony flyingfish (Hirundichthys oxycephalus) is the primary component of flyingfish-egg fishery captures in the northeastern waters of Taiwan, and is also one of the dominant species of flyingfish in eastern waters of Taiwan. In recent years, people are conscious of overfishing in negarding to the continuously decreasing flyingfish resources. For rational management and sustainability of the fishery, there is an urgent need to study age and growth of the fish. Based on the laboratory-reared fish from the fertilized eggs collected in the wild, the daily periodicity of growth increments in three pairs of otoliths (lapillus, sagitta and asteriscus) was validated. First growth increment formed in the first day after hatching for sagitta and lupillus, and was in the eleven day after hatching for Asteriscus. ¡@¡@Ages of the wild flyingfish sample of 5.4~229.1 mm FL collected by drifted gillnets in Hualian, Taitung, Lyudao and Lanyu waters during April 2009 to March 2010, were determined by daily growth increment (DGI) counting in asteriscus, as adjusted by an addition of 11 DGIs. The von Bertalanffy growth parameters of the fish were estimated to be 253.9 mm in asymptotic length and 0.00753 mm d-1 in growth coefficient. Use DGIs estimation hatch date from otolith ringing, and estimated spawning date by deduct from 3 day hatch requisition. we found 2 recruitment group in eastern Taiwan within a year, most fish hatched either in summer or winter. In this study showing that bony flyingfish was an grew fast and had long longevity sp., therefore, on fishery management, we should decrease the fishing pressure and give them enough surplus biomass, so the biomass could recover rapidly. And we found two recruitment group, one could behalf of stock from east taiwan, and maybe it could behalf of two stocks ,on the other hand the method of fishery management should be a quite different .We suggest to confirm by the further reproductive biology research.
2

Impacts of the Invasive White Perch on the Fish Assemblage of Kerr Reservoir, Virginia

Harris, Johnathan 22 June 2006 (has links)
The white perch (Morone americana) is a highly successful invader of freshwater systems, with negative consequences to some resident fishes. White perch are ovivores and may prey upon as well as compete with juvenile sportfishes. Since 1988, an introduced population of white perch has proliferated in the 19,790-ha Kerr Reservoir, NC-VA, potentially threatening popular sport fisheries for largemouth bass (Micropterus salmoides), crappie (Pomoxis spp.), and self-sustaining striped bass (Morone saxatilis). Trophic relationships between white perch and resident sportfish were examined in the Kerr Reservoir system to determine the white perch's impact on them. Striped bass eggs were found in the stomach contents of white perch collected from the Roanoke River during their concurrent spawning runs in May, and at times egg predation was intense (frequency of egg occurrence in white perch individuals up to 100 %). However, modeling simulations indicated that observed densities of white perch in the Roanoke River during the peak spawning period of striped bass (May) were too low to have a substantial effect on striped bass recruitment. Crappie eggs were found in the diets of white perch collected from Kerr Reservoir during April, but the significance of this predation was not determined. Trophic overlap (Schoener's Index) was high (> 0.5) between age-0 white perch and age-0 crappie, largemouth bass, and striped bass in June, but only remained high between white perch and crappie in the remainder of the growing season (July – September). After June, largemouth and striped bass were primarily piscivorous, whereas white perch and crappie remained primarily invertivorous. Trophic overlap was high between adult white perch and adult crappie (> 0.6), but not between white perch and any other species of adult sportfish. The utilization of white perch by adult piscivores (Ictalurids, Pomoxis spp., Moronids, and Percids) as a food source was low (< 2% of diets by weight). Piscivorous sportfish primarily ate clupeids, which are highly abundant in Kerr Reservoir. Analysis of sportfish performance before (1974 – 1987) versus after (1996 – 2005) white perch establishment indicated no change in abundance and growth of striped bass and largemouth bass. Performance data for crappie prior to white perch introductions were unavailable, but observed egg predation by and trophic overlap with white perch suggests that crappie have the highest potential to suffer deleterious interactions with the white perch. Abundance of white bass has significantly declined in years since white perch introductions. Future research in Kerr Reservoir should concentrate on interactions between white perch and these two species. / Master of Science
3

Estimativa da idade do polvo, Octopus insularis capturado com espinhel de potes no Ceará, relacionada com os estágios de maturação gonadal / Estimate age of octopus, Octopus insularis caught in ceará with longline pots, connection with the stages of maturation gonadal

Batista, Bruno Braulino January 2011 (has links)
BATISTA, Bruno Braulino. Estimativa da idade do polvo, Octopus insularis capturado com espinhel de potes no Ceará, relacionada com os estágios de maturação gonadal. 2011. 69 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia de Pesca, Fortaleza-CE, 2011 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-11T13:04:21Z No. of bitstreams: 1 2011_dis_bbbatista.pdf: 1454663 bytes, checksum: ac60152ab78db40c316343aaed5b352a (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-11T13:04:40Z (GMT) No. of bitstreams: 1 2011_dis_bbbatista.pdf: 1454663 bytes, checksum: ac60152ab78db40c316343aaed5b352a (MD5) / Made available in DSpace on 2016-07-11T13:04:40Z (GMT). No. of bitstreams: 1 2011_dis_bbbatista.pdf: 1454663 bytes, checksum: ac60152ab78db40c316343aaed5b352a (MD5) Previous issue date: 2011 / The growing interest in cephalopod fisheries due to overexploitation of the main fishing resources (teleosts and crustaceans). In Ceará, fishing for octopus Octopus insularis, started in 2004, as an alternative to the closed lobster season, but only in 2005 the fishery has become effectively trade. For the management of a fishery, growth and reproduction are the main factors to be studied, the main factors that affect growth are temperature and salinity. This study aimed to investigate qualitative and quantitatively morphometry to quantify the age, to validate the methodology, and the proportion of sexual maturity with morphometric variables (CM and Wt) and number of days. 20 specimens were sampled monthly, and their morphometric variables collected from the body and the upper beak, the validation of the quantification was done using the marker oxytetracycline (OTC), the quantification of age was performed by counting the number of increments of lateral wall the upper beak, the proportion by gonadal macroscopic characterization of the gonads. The growth of the octopus, Octopus insularis was influenced by temperature, in which the octopuses in the rainy season had higher values of dorsal mantle length and total weight. Moreover, the difference between the slopes (b) of the regressions for females showed that octopuses grow different between sexes and according to time of year (dry or wet). The marking of lines increase the sidewalls of the nozzles showed a profile of daily deposition, and thus the species has an extremely short life cycle of up to 6 months (180 days) and thus demonstrating that these animals are rapidly growing . Quantification of age on the sidewalls of the upper beak showed good correlation with the length of the dorsal mantle and crest length of the upper beak, but a weak correlation was obtained with the total weight. In this study, we used only octopuses sub-adults and adults, but still need to study the profile of deposition of rings in the side wall of the upper beak of paralarvas. / O crescimento do interesse pela pesca de cefalópode deve-se a sobre-explotação dos principais recursos pesqueiros (teleósteos e crustáceos). No Ceará, a pesca do polvo Octopus insularis, iniciou-se em 2004, como alternativa para a época de defeso da lagosta, mas somente em 2005 a pescaria tornou-se efetivamente comercial. Para a administração de uma pescaria o crescimento e a reprodução são os principais fatores a serem estudados, sendo os principais fatores que podem afetar o crescimento são a temperatura e salinidade. Esse trabalho teve como objetivo, analisar quali-quantitivamente a morfometria, quantificar a idade, validar a metodologia, e relação à proporção de maturidade gonadal com variáveis morfométricas (CM e Wt) e nº de dias. Foram amostrados 20 exemplares mensalmente, e deles coletadas variáveis morfométricas do corpo e do bico superior, a validação da quantificação foi feita com a utilização do marcador oxitetraciclina (OTC), a quantificação da idade foi realizada através da contagem do número de anéis etários da parede lateral do bico superior, a proporção gonadal através da caracterização macroscópica das gônadas. O crescimento dos polvos, Octopus insularis foi influenciado pela temperatura, em que os polvos no período chuvoso apresentaram maiores valores de comprimento dorsal do manto e peso total. Além disso, a diferença entre os coeficientes angulares (b) das regressões para as fêmeas mostrou que os polvos crescem diferentes entre os sexos e de acordo com o período do ano (seco ou chuvoso). A marcação das linhas de incremento nas paredes laterais dos bicos demonstrou um perfil de deposição diário, e assim a espécie apresenta um ciclo de vida extremamente curto de no máximo 6 meses de idade (180 dias) e assim demonstrando que esses são animais de crescimento rápido. A quantificação da idade nas paredes laterais do bico superior mostrou boa correlação com o comprimento dorsal do manto e o comprimento da crista do bico superior, porém foi obtida uma fraca correlação com o peso total. Nesse trabalho, foram utilizados somente polvos sub-adultos e adultos, porém ainda é necessário estudo do perfil de deposição de anéis na parede lateral do bico superior das paralarvas.
4

Idade e crescimento do tubarão Aneqim, Isurus Oxyrinchus (Rafinesque 1810), no Atlântico sudoeste

Melleras, Florencia Doño January 2013 (has links)
Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós–Graduação em Oceanografia Biológica, Instituto de Oceanografia, 2013. / Submitted by Cristiane Gomides (cristiane_gomides@hotmail.com) on 2013-11-19T12:52:38Z No. of bitstreams: 1 florencia.pdf: 2100442 bytes, checksum: 41f46ff0b9c28e5fa20e9fad129e691f (MD5) / Approved for entry into archive by Angelica Miranda (angelicacdm@gmail.com) on 2013-11-20T21:43:14Z (GMT) No. of bitstreams: 1 florencia.pdf: 2100442 bytes, checksum: 41f46ff0b9c28e5fa20e9fad129e691f (MD5) / Made available in DSpace on 2013-11-20T21:43:14Z (GMT). No. of bitstreams: 1 florencia.pdf: 2100442 bytes, checksum: 41f46ff0b9c28e5fa20e9fad129e691f (MD5) Previous issue date: 2013 / O tubarão anequim Isurus oxyrinchus é uma espécie frequente na captura incidental da pesca oceânica de espinhel no Atlântico Sul. Apesar disso, estudos de idade e crescimento não têm sido realizados para a espécie na região. O presente estudo forneceu as primeiras estimativas de idade e crescimento do tubarão anequim no Atlântico Sudoeste através da análise de secções vertebrais de 245 exemplares (126 fêmeas, 116 machos e 3 com sexo indeterminado), com uma amplitude de tamanhos de 78 a 330 cm de comprimento furcal (CF). A relação entre o raio da vértebra e o CF foi linear. As análises do incremento marginal não foram conclusivas em relação à periodicidade de formação das bandas de crescimento na área do estudo. Assumindo uma periodicidade anual (uma banda de crescimento por ano), a amplitude de idades estimada foi de 0 a 28 anos. O modelo de crescimento de Schnute, escolhido por sua flexibilidade e ajustado sob uma abordagem bayesiana, forneceu uma boa descrição do crescimento individual para ambos os sexos até os 15 anos de idade. O crescimento no primeiro ano de vida foi 33.9 cm (ICr95% = 19.9 – 40.8) para as fêmeas e 30.5 cm (ICr95% = 25.6 - 35.4) para os machos. Até aproximadamente 15 anos de idade, fêmeas e machos apresentaram crescimento semelhante, atingindo ~217 cm CF. A forma sigmoide que apresentaram as curvas de crescimento de ambos os sexos indicou que existe uma mudança no padrão de crescimento em torno dos 7 anos de idade. Os resultados inconclusivos sobre a periodicidade na deposição das bandas de crescimento na área de estudo fazem com que seja necessária a aplicação de técnicas mais robustas de validação no futuro. Enquanto isso, uma abordagem preventiva que assuma um padrão de deposição anual no Atlântico Sudoeste pode ser utilizada para a avaliação e manejo dos estoques dessa espécie, caracterizada por uma baixa fertilidade e uma maturidade tardia. / The shortfin mako shark Isurus oxyrinchus is a frequent by-catch species in oceanic longline fisheries in the South Atlantic. Despite this, no age and growth studies have been conducted for the species in the region. This study provided the first age and growth estimates of female and male shortfin mako sharks from the western South Atlantic through the analysis of vertebral sections of 245 specimens (126 females, 116 males and 3 with undetermined sex), ranging in size from 78 to 330 cm fork length (FL). A significant linear relationship was found between FL and vertebral radius for sexes combined. Marginal increment analyses were inconclusive about periodicity of growth band deposition and an annual periodicity (one growth band per year) was assumed to make age estimations. Specimens were estimated to be between 0 and 28 years of age. The Schnute growth model (SGM), chosen for its flexibility and fitted with a Bayesian approach, provided a good description of the individual growth for both sexes up to 15 years of age. Shortfin mako growth during the first year of life was 33.9 cm (ICr95% = 19.9 – 40.8) for females and 30.5 cm (ICr95% = 25.6 - 35.4) for males. Until approximately 15 years of age, both sexes showed similar growth and reached ~217 cm FL. Sigmoid shaped growth curves obtained for both sexes indicated a change in the growth pattern close to 7 years of age. Inconclusive results about periodicity of growth band deposition in the study area make necessary the application of more robust validation techniques in the future. Meanwhile, a precautionary approach that assumes an annual deposition pattern in the western South Atlantic can be used for the assessment and management of stocks of this species, characterized by low fecundity and late maturity.
5

Estimativa da idade do polvo, Octopus insularis capturado com espinhel de potes no CearÃ, relacionada com os estÃgios de maturaÃÃo gonadal / Estimate age of octopus, Octopus insularis caught in cearà with longline pots, connection with the stages of maturation gonadal

Bruno Braulino Batista 19 January 2011 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O crescimento do interesse pela pesca de cefalÃpode deve-se a sobre-explotaÃÃo dos principais recursos pesqueiros (teleÃsteos e crustÃceos). No CearÃ, a pesca do polvo Octopus insularis, iniciou-se em 2004, como alternativa para a Ãpoca de defeso da lagosta, mas somente em 2005 a pescaria tornou-se efetivamente comercial. Para a administraÃÃo de uma pescaria o crescimento e a reproduÃÃo sÃo os principais fatores a serem estudados, sendo os principais fatores que podem afetar o crescimento sÃo a temperatura e salinidade. Esse trabalho teve como objetivo, analisar quali-quantitivamente a morfometria, quantificar a idade, validar a metodologia, e relaÃÃo à proporÃÃo de maturidade gonadal com variÃveis morfomÃtricas (CM e Wt) e n de dias. Foram amostrados 20 exemplares mensalmente, e deles coletadas variÃveis morfomÃtricas do corpo e do bico superior, a validaÃÃo da quantificaÃÃo foi feita com a utilizaÃÃo do marcador oxitetraciclina (OTC), a quantificaÃÃo da idade foi realizada atravÃs da contagem do nÃmero de anÃis etÃrios da parede lateral do bico superior, a proporÃÃo gonadal atravÃs da caracterizaÃÃo macroscÃpica das gÃnadas. O crescimento dos polvos, Octopus insularis foi influenciado pela temperatura, em que os polvos no perÃodo chuvoso apresentaram maiores valores de comprimento dorsal do manto e peso total. AlÃm disso, a diferenÃa entre os coeficientes angulares (b) das regressÃes para as fÃmeas mostrou que os polvos crescem diferentes entre os sexos e de acordo com o perÃodo do ano (seco ou chuvoso). A marcaÃÃo das linhas de incremento nas paredes laterais dos bicos demonstrou um perfil de deposiÃÃo diÃrio, e assim a espÃcie apresenta um ciclo de vida extremamente curto de no mÃximo 6 meses de idade (180 dias) e assim demonstrando que esses sÃo animais de crescimento rÃpido. A quantificaÃÃo da idade nas paredes laterais do bico superior mostrou boa correlaÃÃo com o comprimento dorsal do manto e o comprimento da crista do bico superior, porÃm foi obtida uma fraca correlaÃÃo com o peso total. Nesse trabalho, foram utilizados somente polvos sub-adultos e adultos, porÃm ainda à necessÃrio estudo do perfil de deposiÃÃo de anÃis na parede lateral do bico superior das paralarvas. / The growing interest in cephalopod fisheries due to overexploitation of the main fishing resources (teleosts and crustaceans). In CearÃ, fishing for octopus Octopus insularis, started in 2004, as an alternative to the closed lobster season, but only in 2005 the fishery has become effectively trade. For the management of a fishery, growth and reproduction are the main factors to be studied, the main factors that affect growth are temperature and salinity. This study aimed to investigate qualitative and quantitatively morphometry to quantify the age, to validate the methodology, and the proportion of sexual maturity with morphometric variables (CM and Wt) and number of days. 20 specimens were sampled monthly, and their morphometric variables collected from the body and the upper beak, the validation of the quantification was done using the marker oxytetracycline (OTC), the quantification of age was performed by counting the number of increments of lateral wall the upper beak, the proportion by gonadal macroscopic characterization of the gonads. The growth of the octopus, Octopus insularis was influenced by temperature, in which the octopuses in the rainy season had higher values of dorsal mantle length and total weight. Moreover, the difference between the slopes (b) of the regressions for females showed that octopuses grow different between sexes and according to time of year (dry or wet). The marking of lines increase the sidewalls of the nozzles showed a profile of daily deposition, and thus the species has an extremely short life cycle of up to 6 months (180 days) and thus demonstrating that these animals are rapidly growing . Quantification of age on the sidewalls of the upper beak showed good correlation with the length of the dorsal mantle and crest length of the upper beak, but a weak correlation was obtained with the total weight. In this study, we used only octopuses sub-adults and adults, but still need to study the profile of deposition of rings in the side wall of the upper beak of paralarvas.
6

Der Einfluss der Altersstruktur auf das Wachstum und die Produktivität von Regionen

Brunow, Stephan 27 November 2009 (has links)
Die regionale altersstrukturelle Zusammensetzung in Europa und Deutschland ist sehr heterogen. In der Literatur werden viele Diskussionen darüber geführt, wie sich unter anderem Regionen in Zukunft entwickeln werden und ob es ggf. zu einer Entvölkerung einzelner Gebiete kommt. Allerdings sind bisher nur selten Untersuchungen vorgenommen worden, welche die Auswirkungen der altersstrukturellen Zusammensetzung auf die regionale Produktivität und das regionale Wachstum sind. Diese Lücke wird im Rahmen dieser Arbeit weiter vervollständigt. Zunächst wird ein neoklassisches Wachstumsmodell in Anlehnung an Mankiw, Romer und Weil (1992) angewandt und um öffentliche Investitionen erweitert. Das Untersuchungsfeld sind europäische und deutsche Regionen. Im Anschluss wird untersucht, inwiefern die regionale Altersstruktur Humankapitalexternalitäten generiert. Hierzu wird eine Produktionsfunktion in Anlehnung an Lucas (1988) geschätzt. Anschließend wird ein simultanes Gleichungssystem für eine Schätzgleichung motiviert, die der Arbeit von Baldwin (1999) folgt. Es zeigt sich, dass Unterschiede in der regionalen Produktivität und des Wachstums durch altersstrukturelle Variationen erklärt werden kann. / The composition of the regional age pattern of the population and labour force within Europe and Germany is quiet heterogenous. Within the existing literature there is a debate on regional development and the possibility of depopulation. However, there is only limited evidence on the effect of the composition of the age pattern on regional productivity and growth. The aim of this work is to fill this gap. To adress this issues an augmented neoclassical growth model of Mankiw, Romer and Weil (1992) is applied. Additionally, public spendings are controlled for. The model is tested on European and German regions. The next section focuses on productivity, esp. whether the age structure of human capital effects human capital externalities. First, a production function in a Lucas (1988) fashion is estimated. Second, a simultaneous equation model based on the conceptual ideas of Baldwin (1999) is applied. One can conclude that differences in regional productivity and growth is due to variation of the age pattern of the labour force and population.
7

Crescimento relativo e idade de embriões do Tubarão-Azul, Prionace glauca (Linnaeus, 1758) no Sudeste-Sul do Brasil. / Age and relative growth of the blue shark embryos, Prionace glauca (Linnaeus, 1758) in the southwestern Atlantic.

Caltabellotta, Fabio Prior 06 November 2009 (has links)
O tubarão-azul, Prionace glauca, é uma das espécies de elasmobrânquios pelágicos, mais capturadas pela frota de espinhel-de-superfície. No presente estudo analisou-se o crescimento relativo e a idade de 83 embriões, provenientes de fêmeas grávidas capturadas em 1998, durante o Programa Avaliação do Potencial Sustentável de Recursos Vivos da Zona Econômica Exclusiva REVIZEE, na região Sudeste-Sul do Brasil. Foram analisados 48 caracteres morfométricos, verificando-se que entre as variáveis morfométricas mais expressivas, o comprimento furcal, o comprimento pré-caudal, o comprimento inicial da segunda nadadeira dorsal, o comprimento pré-anal e o comprimento pré-pélvico contribuíram com valores acima de 50% na composição do corpo do embrião. Por meio de regressões lineares de variáveis logaritmizadas, constatou-se alometria negativa em (53,2%), positiva em (36,1%) e isometria em (10,7%) dos caracteres morfométricos analisados. A idade de cada embrião foi estimada por meio da utilização do método da proporção direta modificada de Dahl-Lea, e os parâmetros de crescimento foram ajustados através das curvas de crescimento logística, de von Bertalanffy e de Gompertz. De acordo com os critérios de seleção de Akaike (AICmin, i e wi) e da soma dos quadrados dos erros (SQE), o modelo de Gompertz foi escolhido como o melhor representante do crescimento embrionário de P.glauca. / The blue shark, Prionace glauca, is a pelagic elasmobranchs, mainly captured by the Brazilian pelagic longline fleet. In this study we analyzed both the relative growth and the age of 83 of pregnant females captured in 1998 during the Program \"Evaluation of the Sustainable Potential of Living Resources of the Exclusive Economic Zone\" - REVIZEE in the Brazilian Southeast-South region. We analyzed 48 morphometric characters, showing that among the most expressive, fork length, the length pre-flow, the initial length of the second dorsal fin, the length pre-anal and the length pre-pelvic represented above 50% of the composition of the embryos bodies. By means of linear regressions of logarithmic morphometric variables values, we found negative allometry (53.2%), positive allometry (36.1%) and isometry in (10.7%). The age of each embryo was estimated applying the direct proportion of Dahl-Lea method modified, and the parameters of growth were adjusted to logistic growth curves of von Bertalanffy and Gompertz. According to the selection criteria of Akaike (AICmin, i and wi) and the sum of the squares of errors (SSE), the Gompertz model was chosen as the most representative of the growth of P.glauca embryos.
8

Crescimento relativo e idade de embriões do Tubarão-Azul, Prionace glauca (Linnaeus, 1758) no Sudeste-Sul do Brasil. / Age and relative growth of the blue shark embryos, Prionace glauca (Linnaeus, 1758) in the southwestern Atlantic.

Fabio Prior Caltabellotta 06 November 2009 (has links)
O tubarão-azul, Prionace glauca, é uma das espécies de elasmobrânquios pelágicos, mais capturadas pela frota de espinhel-de-superfície. No presente estudo analisou-se o crescimento relativo e a idade de 83 embriões, provenientes de fêmeas grávidas capturadas em 1998, durante o Programa Avaliação do Potencial Sustentável de Recursos Vivos da Zona Econômica Exclusiva REVIZEE, na região Sudeste-Sul do Brasil. Foram analisados 48 caracteres morfométricos, verificando-se que entre as variáveis morfométricas mais expressivas, o comprimento furcal, o comprimento pré-caudal, o comprimento inicial da segunda nadadeira dorsal, o comprimento pré-anal e o comprimento pré-pélvico contribuíram com valores acima de 50% na composição do corpo do embrião. Por meio de regressões lineares de variáveis logaritmizadas, constatou-se alometria negativa em (53,2%), positiva em (36,1%) e isometria em (10,7%) dos caracteres morfométricos analisados. A idade de cada embrião foi estimada por meio da utilização do método da proporção direta modificada de Dahl-Lea, e os parâmetros de crescimento foram ajustados através das curvas de crescimento logística, de von Bertalanffy e de Gompertz. De acordo com os critérios de seleção de Akaike (AICmin, i e wi) e da soma dos quadrados dos erros (SQE), o modelo de Gompertz foi escolhido como o melhor representante do crescimento embrionário de P.glauca. / The blue shark, Prionace glauca, is a pelagic elasmobranchs, mainly captured by the Brazilian pelagic longline fleet. In this study we analyzed both the relative growth and the age of 83 of pregnant females captured in 1998 during the Program \"Evaluation of the Sustainable Potential of Living Resources of the Exclusive Economic Zone\" - REVIZEE in the Brazilian Southeast-South region. We analyzed 48 morphometric characters, showing that among the most expressive, fork length, the length pre-flow, the initial length of the second dorsal fin, the length pre-anal and the length pre-pelvic represented above 50% of the composition of the embryos bodies. By means of linear regressions of logarithmic morphometric variables values, we found negative allometry (53.2%), positive allometry (36.1%) and isometry in (10.7%). The age of each embryo was estimated applying the direct proportion of Dahl-Lea method modified, and the parameters of growth were adjusted to logistic growth curves of von Bertalanffy and Gompertz. According to the selection criteria of Akaike (AICmin, i and wi) and the sum of the squares of errors (SSE), the Gompertz model was chosen as the most representative of the growth of P.glauca embryos.
9

Biology of Arabian Gulf sailfish

Hoolihan, John Paul Jr., School of Biological, Earth & Environmental Sciences, UNSW January 2005 (has links)
Biological and life history characteristics for a previously unstudied population of sailfish, Istiophorus platypterus, in the Arabian Gulf were investigated. Notable findings include temporal-spatial migration patterns for a genetically isolated population that is threatened by overexploitation. Conventional tagging resulted in 2053 releases and 114 recaptures (5.55%) inside the Gulf. Linear displacement ranged from 2.5 to 697 km, while days at liberty ranged from 17 to 818 days. Dead recoveries in Iranian gillnets account for 88.6% of recaptures. Modeling analyses produced a best estimate of annual survival probability (S) at 0.375 (slope = -0.101, SE = 0.324). Fifteen pop-up satellite archival tags were deployed on sailfish during 2001 - 2002 to track temporal and spatial movements. Extensive data from four tags showed 83.7% of time-at-depth was spent above 10 m with no significant difference (P &lt 0.05) in diel preference. Depth ranged from 0.0 m to 61.0 m, while temperature ranged from 19.7 ??C to 30.1 ??C. Small-scale movements of eight sailfish were measured using ultrasonic tracking for periods ranging from 3:33 to 53:06 hours. Track distances ranged from 5.5 to 78.5 km, while linear displacement ranged from 4.6 to 37.0 km. Average speed ranged from 0.29 to 0.75 m s-1. Vertical distributions showed 84.3% of time was spent above 10 m depth, even though water temperature showed negligible variation with depth. Mitochondrial DNA comparison of 147 sailfish produced 39 composite haplotypes using eight restriction enzymes. Significant differences occurred in the frequency between population groups inside and outside the Gulf (amova 34.8%, P &lt 0.01; FST = 0.356), along with evidence of restricted migration between them (average number of migrants, Nm = 0.903). Nine year classes (0-8) were determined from aging analysis of fin spines. Females (n = 50) ranged from 0 to 8 years, while males (n = 34) ranged from 0 to 6 years. Von Bertalanffy growth function indicated rapid growth during the first two years, after which males stabilized and females continued growing to a greater maximum mean length and weight. A comparison of allometric growth between sexes indicated no significant difference between length and other morphometric characters (P ranged 0.135 ??? 0.980).
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Biology of Arabian Gulf sailfish

Hoolihan, John Paul Jr., School of Biological, Earth & Environmental Sciences, UNSW January 2005 (has links)
Biological and life history characteristics for a previously unstudied population of sailfish, Istiophorus platypterus, in the Arabian Gulf were investigated. Notable findings include temporal-spatial migration patterns for a genetically isolated population that is threatened by overexploitation. Conventional tagging resulted in 2053 releases and 114 recaptures (5.55%) inside the Gulf. Linear displacement ranged from 2.5 to 697 km, while days at liberty ranged from 17 to 818 days. Dead recoveries in Iranian gillnets account for 88.6% of recaptures. Modeling analyses produced a best estimate of annual survival probability (S) at 0.375 (slope = -0.101, SE = 0.324). Fifteen pop-up satellite archival tags were deployed on sailfish during 2001 - 2002 to track temporal and spatial movements. Extensive data from four tags showed 83.7% of time-at-depth was spent above 10 m with no significant difference (P &lt 0.05) in diel preference. Depth ranged from 0.0 m to 61.0 m, while temperature ranged from 19.7 ??C to 30.1 ??C. Small-scale movements of eight sailfish were measured using ultrasonic tracking for periods ranging from 3:33 to 53:06 hours. Track distances ranged from 5.5 to 78.5 km, while linear displacement ranged from 4.6 to 37.0 km. Average speed ranged from 0.29 to 0.75 m s-1. Vertical distributions showed 84.3% of time was spent above 10 m depth, even though water temperature showed negligible variation with depth. Mitochondrial DNA comparison of 147 sailfish produced 39 composite haplotypes using eight restriction enzymes. Significant differences occurred in the frequency between population groups inside and outside the Gulf (amova 34.8%, P &lt 0.01; FST = 0.356), along with evidence of restricted migration between them (average number of migrants, Nm = 0.903). Nine year classes (0-8) were determined from aging analysis of fin spines. Females (n = 50) ranged from 0 to 8 years, while males (n = 34) ranged from 0 to 6 years. Von Bertalanffy growth function indicated rapid growth during the first two years, after which males stabilized and females continued growing to a greater maximum mean length and weight. A comparison of allometric growth between sexes indicated no significant difference between length and other morphometric characters (P ranged 0.135 ??? 0.980).

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