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Evaluating successful conservation partnerships between zoos and aquariums, federal and state agencies and non-governmental organizationsSmith, Kathleen Nicole January 2005 (has links) (PDF)
Thesis (M. S.)--Oklahoma State University, 2005. / Vita. Includes bibliographical references (p. 86-93).
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Crescimento e dinâmica reprodutiva do camarão-ferrinho Rimapenaeus constrictus (Stimpson, 1874) (Penaeoidea) no litoral norte do estado de São Paulo síntese de cinco anos de estudo /Lopes, Ana Elisa Bielert January 2017 (has links)
Orientador: Antonio Leão Castilho / Resumo: This is the first study to evaluate in broad spatiotemporal scales the growth parameters and population structure of Rimapenaeus constrictus, a barely damaged species composing the bycatch from shrimp fishing in the Western Atlantic. The abundance and size-class frequency distribution, growth, longevity and sex ratio were evaluated from monthly samples obtained in the northern littoral of São Paulo state from Jan/1998 to Jun/2003. We measured 5,812 individuals in which the sex ratio was skewed toward females; this was more evident in size classes greater than 10 mm in CL (carapace length) (binomial test, p<0.05). We selected 16 growth cohorts of females, and 8 of males, the majority consisting of younger individual cohorts excluded from the fisheries closure period. Growth estimates resulted in a CL∞ of 17.42 mm, a growth coefficient of 0.008 and a longevity of 579 days (1.60 year) for females, as well as a CL∞ of 16.3 mm, a growth coefficient of 0.01 and a longevity of 425 days (1.17 year) for males. Our results provide information of incontestable relevance to our knowledge of fishing management. We therefore strongly recommend that the fisheries closure period be changed to protect this species’ recruitment period and consequently its adult individuals. The reproduction and recruitment were analyzed in order to determine the size at the onset of sexual maturity, the reproductive and recruitment patterns and the copulation period. In our study, 6,456 shrimps were captured a... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
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Crescimento e dinâmica reprodutiva do camarão-ferrinho Rimapenaeus constrictus (Stimpson, 1874) (Penaeoidea) no litoral norte do estado de São Paulo: síntese de cinco anos de estudo / Growth and reproductive dynamics of the roughneck shrimp Rimapenaeus constrictus (Stimpson, 1874) (Penaeoidea) on the north coast of the São Paulo state: synthesis of a five-year studyLopes, Ana Elisa Bielert [UNESP] 02 August 2017 (has links)
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Previous issue date: 2017-08-02 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / This is the first study to evaluate in broad spatiotemporal scales the growth parameters and population structure of Rimapenaeus constrictus, a barely damaged species composing the bycatch from shrimp fishing in the Western Atlantic. The abundance and size-class frequency distribution, growth, longevity and sex ratio were evaluated from monthly samples obtained in the northern littoral of São Paulo state from Jan/1998 to Jun/2003. We measured 5,812 individuals in which the sex ratio was skewed toward females; this was more evident in size classes greater than 10 mm in CL (carapace length) (binomial test, p<0.05). We selected 16 growth cohorts of females, and 8 of males, the majority consisting of younger individual cohorts excluded from the fisheries closure period. Growth estimates resulted in a CL∞ of 17.42 mm, a growth coefficient of 0.008 and a longevity of 579 days (1.60 year) for females, as well as a CL∞ of 16.3 mm, a growth coefficient of 0.01 and a longevity of 425 days (1.17 year) for males. Our results provide information of incontestable relevance to our knowledge of fishing management. We therefore strongly recommend that the fisheries closure period be changed to protect this species’ recruitment period and consequently its adult individuals. The reproduction and recruitment were analyzed in order to determine the size at the onset of sexual maturity, the reproductive and recruitment patterns and the copulation period. In our study, 6,456 shrimps were captured among which 5,774 were measured, which 4,322 were females and 1,452 were males. The estimated maturity was 8.3 mm and 11.2 mm, for males and females, respectively. Reproductive females were found over the 5-year study. These results suggests a continuous reproduction pattern, with peaks in summer and in spring. We verified a positive significant relation between reproductive females and temperature (lag +1 and +3), although the decrease in bottom water temperature in some peaks of reproductive activity (spawning), which was probably induced due to SACW intrusion. The recruitment was considered episodic and even though no significant relation was found between immatures and reproductive females, we suggested that the main recruitment peaks observed were a consequence of the major reproductive activities a few months prior to it. The copulation period was continuous in the sampled period, and ISP females (recently copulated) were significant correlated with reproductive males (lag 0). Thus, we propose that during this period the sexual proportion is 1:1, probably due to the migration of reproductive males, attracted to copulate. Our results provide information of incontestable relevance to our wide knowledge of the species’ reproductive biology, in order to support an accurate fishing management. / FAPESP: 2015/13639-5
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Biologia pesqueira das raias Dasyatis guttata (bloch & schneider, 1801) e Dasyatis Americana Hildebrand & Schroeder, 1928, no Estado do Cearà / Fisheries biology of rays Dasyatis guttata (Bloch & Schneider, 1801) and Dasyatis Americana Hildebrand & Schroeder, 1928 in the state of CearÃGuelson Batista da Silva 06 July 2005 (has links)
FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / As raias das espÃcies Dasyatis guttata e Dasyatis americana constituem importantes recursos pesqueiros no Estado do CearÃ. O objetivo geral desta DissertaÃÃo à estudar a biologia pesqueira dessas espÃcies com vistas ao uso das informaÃÃes como constituintes de eventuais medidas de gerenciamento de sua exploraÃÃo. Dentro desse contexto geral, foram abordados aspectos relacionados com a biometria e suas relaÃÃes morfomÃtricas, dieta alimentar e reproduÃÃo, quanto ao comprimento mÃdio na 1 maturidade sexual e fecundidade. As amostragens foram realizadas nos MunicÃpios de Fortaleza, Caucaia e Aquiraz, no Estado do CearÃ, Brasil, a partir da captura como fauna acompanhante das pescarias com rede-de-arrasto e rede-de-espera, e dos desembarques das pescarias com linha-de-mÃo e mergulho (arpÃo), durante os perÃodos de julho e agosto de 1997; fevereiro a julho de 1999; agosto de 2000; marÃo a junho de 2001; outubro a dezembro de 2003; e janeiro de 2004 a maio de 2005. O crescimento relativo das medidas lineares comprimento do disco (CD), distÃncia focinho-olho (FO), distÃncia focinho-boca (FB), largura da boca (LB), comprimento dos clÃspers (CC) e peso total (PT) â variÃveis dependentes, como proporÃÃo da largura do disco (LD) â variÃvel independente, foi estimado atravÃs do Ãndice MorfomÃtrico (IM) e das relaÃÃes moformÃtricas lineares CD/LD, FO/LD, FB/LD, LB/LD e CC/LD e PT/LD. A ocorrÃncia de dimorfometria sexual foi avaliada atravÃs do teste t, aplicado ao coeficiente angular para machos (b1) e fÃmeas (b2). DiferenÃas no tamanho entre machos e fÃmeas tambÃm foram avaliadas pelo teste t. A alimentaÃÃo foi analisada quanto ao Ãndice de RepleÃÃo Estomacal, e quanto à dieta pelos mÃtodos da freqÃÃncia de ocorrÃncia, avaliaÃÃo volumÃtrica e avaliaÃÃo gravimÃtrica. A reproduÃÃo foi estudada quanto ao desenvolvimento da maturaÃÃo sexual e estimaÃÃo do comprimento na 1Â. maturidade sexual atravÃs do mÃtodo da ogiva. A fecundidade das espÃcies foi estimada atravÃs da contagem do nÃmero de embriÃes por fÃmea grÃvida. A anÃlise dos dados permitiu a obtenÃÃo dos seguintes resultados: (1) D guttata foi considerada como espÃcie-alvo das pescarias com linha-de-mÃo, sendo tambÃm capturada como fauna acompanhante nas pescarias direcionadas a camarÃes e lagostas com redes de arrasto e de espera, enquanto D. americana foi considerada como espÃcie-alvo das pescarias com linha-de-mÃo e mergulho, sendo capturadas em fundos lamosos e arenosos, respectivamente; (2) D. americana apresentou um porte bem maior que D. guttata, as fÃmeas sÃo maiores do que os machos; (3) foram observadas diferenÃas entre sexos quanto ao crescimento relativo das variÃveis âdistÃncia focinho-bocaâ em ambas as espÃcies, e âdistÃncia focinho-olhoâ em D. americana; (3) a dieta apresentou a seguinte estrutura: alimentos essenciais - crustÃceos (D. guttata), crustÃceos e peixes (D. americana); alimentos secundÃrios - peixes, poliquetas e sipunculas (D. guttata); alimentos ocasionais - moluscos e outros (D. guttata), poliquetas, sipunculas e moluscos (D. americana); (4) D. americana parece fazer um melhor aproveitamento dos itens alimentares disponÃveis, como o indica seu maior Ãndice de repleÃÃo estomacal; (5) a capacidade de reproduÃÃo à atingida nas classes de 50-60 cm LD e 60-70 cm LD (machos) e 60-70 cm LD e 80-90 cm LD fÃmeas), para D. guttata e D. americana, respectivamente; (6) os clÃspers apresentaram comprimentos mÃdios de 11,2 e 11,8 cm em D. guttata e D. americana, com proporÃÃes praticamente iguais nas duas espÃcies, valores que definem o tamanho mÃdio na 1Â. maturidade funcional; (7) s D. guttata e D. americana apresentaram baixa fecundidade e neonatos com tamanho mÃdio de nascimento estimados em 14,0 cm LD e 29,0 cm LD, respectivamente. / The stingray species are important fishing resources in Cearà State, Brazil. The main objective of this Dissertation was to study the fishery biology of the species Dasyatis guttata e Dasyatis americana, with the aim of using the results as tools in the issuing and enforcing of the appropriate measures for managing their exploitation. Various aspects were studied, such as: biometry, morphometric relationships, feeding diet, and reproductive activity as to the maturation development and mean size at the first sexual maturity and fecundity. Sampling for the stocks was carried out in Fortaleza, Caucaia and Aquiraz counties, in Cearà State, Brazil, as by-catch material by the trawlnet and gillnet fisheries and landings from the hook-and-line fishery and harpooning fisheries, during the period of July and August of 1997; February to July of 1999; August of 2000; March to June of 2001; October to December of 2003; and January of 2004 to May of 2005 . The relative growth of the body measures disk length (DL), distance snout-eye (SE), distance snout-mouth (SM), mouth breadth (MB), claspers length (CL) and total weight (TW) â dependent variables â as a proportion of disk width (DW) â independent variable - was estimated by means of the Morphometric Index and the morphometric relationships DL/DW, SE/DW, SM/DW, MB/DW e CL/DW and TW/DW. The occurrence of sexual dimorphism was assessed through Studentâs t-test applied to the slope coefficient for males (b1) and females (b2). Differences in size between males and females were also evaluated by means of the t-test. Feeding was investigated by the Index of Gut Fullness and diet by the frequency of occurrence and volumetric and gravimetric evaluation methods. Reproduction was investigated as to gonad development and estimation of the mean size at first sexual maturity, the latter by the ogive method. Fecundity of both species was estimating by counting the number of embryos per pregnant female. The data analysis generetd the following results: (1) Dasyatis guttata was considered a target specie of hook-and-line fishery, being also caught as by-catch in the shrimp and lobster fisheries with trawlnets and gillnets and Dasyatis americana was a target species of hook-and-line fishery and harpooning fisheries, they are caught in mud and sand bottoms, respectively; (2) D. americana was larger that D. guttata, and likewise, females were bigger than males; (3) sex differences as to relative growth of variables âdistance snout-mouthâ in both species, and âdistance snout-eyeâ in D. americana; (3) the feeding diet has the following structure: essential foods - crustaceans (D. guttata), crustaceans and fish (D. americana); secondary foods â fish, worms, fish and sipunculids (D. guttata); occasional foods â mollusks and other items (D. guttata), worms, sipunculids and mollusks (D. americana); (4) the stingray D. americana seems to make the most of the ingested food as indicated by the Index of Gut Fullness; (5) the onset of reproduction is attained in length classes de 50-60 cm DW and e 60-70 cm DW (males), and 60-70 cm DW e 80-90 cm DW (females), for D. guttata and D. americana, respectively; (6) the mean length of claspers was estimated as 11.2cm (D. guttata) and e 11.8 cm (D. americana), with roughly equal proportions in both species, values which are thought to define the mean size at first functional maturity; (7) D. guttata e D. americana showed a low fecundity index, with the mean length free-living neonates being estimated as 14.0 cm DW and 29.0 cm DW, respectively.
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Seletividade da rede-de-espera utilizada na captura da sardinha-bandeira, Opisthonema oglinum (Lesueur, 1818) / Selectivity of drift nets used for catching the Atlantic thread-herring, Opisthonema oglinum (Lesueur, 1818)SebastiÃo Ribeiro DÂAlva Teixeira 20 March 2015 (has links)
CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / A sardinha-bandeira, Opisthonema oglinum, pertence à famÃlia Clupeidae da ordem Clupeiformes sendo uma das cinco espÃcies do gÃnero Opisthonema. No Estado do Cearà sua captura se estende ao longo de toda a costa, durante todo o ano, com as melhores pescarias ocorrendo entre maio e dezembro. O presente trabalho teve como objetivo determinar a estrutura da populaÃÃo, a relaÃÃo peso/comprimento da sardinha-bandeira e a seletividade das redes-de-espera utilizadas na sua captura na Praia da Caponga, municÃpio de Cascavel, CearÃ, Brasil. Os dados de comprimento total (cm) e peso individual (g) foram obtidos de dois grupos, cada um com 780 indivÃduos, capturados por redes-de-espera com malhas de 5 cm e 6 cm entre nÃs opostos, no perÃodo de agosto a outubro de 2014. Esses dados foram descritos em histogramas de frequÃncia de comprimento e peso, sendo mais representativas as classes de 21,6 cm (24,23%) e de 87,0 g (32,31%) para a malha de 5 cm e de 25,7 cm (23,08%) e de 117,9 g (26,03%), para a de 6 cm. Quando todos os indivÃduos foram reunidos em um Ãnico grupo (1.560), sem distinÃÃo do tamanho da malha, as classes mais representativas foram a de 23,0 cm de comprimento (18,59%) e a de 105,5 g de peso (20,38%). As equaÃÃes que representaram as relaÃÃes peso/comprimento foram as seguintes: y=0,016 x^2,7636 (780 indivÃduos capturados com a malha de 5 cm); y=0,031 x^2,5635 (780 indivÃduos capturados com a malha de 6 cm); e y=0,021 x^2,6828 (1.560 indivÃduos). Para o estudo da seletividade foram analisados todos os exemplares de sardinha-bandeira (1.560) capturados com as redes-de-espera de malha de 5 cm e 6 cm. O comprimento mÃdio de seleÃÃo foi de 23,7 cm para a malha de 5 cm e de 28,5 cm para a de 6 cm. A amplitude de seleÃÃo foi de 23,7  7,9 cm e de 28,5  7,9 cm para as malhas de 5 cm e 6 cm, respectivamente. As equaÃÃes das curvas de seleÃÃo das redes-de-espera para os dois tamanhos de malha foram obtidas, e a probabilidade de capturar indivÃduos com comprimento inferior ao mÃnimo, estabelecido em 15 cm, foi muito baixa e correspondeu a 1,32% e 0,03% para as malhas de 5 cm e de 6 cm, respectivamente. Esta informaÃÃo à de grande valia para a manutenÃÃo do estoque da sardinha-bandeira capturada na Praia da Caponga, CearÃ. / Atlantic thread-herring, Opisthonema oglinum, belongs to the family Clupeidae and to the order Clupeiformes. It is one of the five species of the genus Opisthonema. In the state of CearÃ, it is caught along the entire coast, throughout the year, with the best fisheries occurring between May and December. This work aimed to study the population structure, the length/weight relationships of the Atlantic thread-herring and to determine gear selectivity of drift nets used for catching them in Caponga Beach, Cascavel, CearÃ, Brazil. Data of total length (cm) and individual weight (g) were obtained from two groups, each with 780 individuals captured by drift nets with meshes of 5 cm and 6 cm, from August to October 2014. These data are showed as histograms. The most representative classes of length and weight were 21.6 cm (24.23%) and 87.0 g (32.31%) for 5 cm mesh, while for the 6 cm mesh, the main classes were 25.7 cm (23.08%) and 117.9 g (26.03%). When all data was combined into a single group (1,560), without the mesh size distinction, the most representative classes were 23.0 cm long (18.59%) and 105.5 g in weight (20.38%). The equations representing the weight/length ratios were as follows: y=0.016 x^2.7636 (780 individuals captured with a mesh of 5 cm); y=0.031 x^2.5635 (780 individuals caught with a mesh of 6 cm); and y=0.021 x^2.6828 (1,560 individuals). To study the selectivity, 1,560 Atlantic thread-herring specimens captured with drift nets of 5 cm and 6 cm were analyzed. The selection mean length was 23.7 cm for 5 cm mesh and 28.5 cm for 6 cm mesh. The range of selection was 23.7  7.9 cm and 28.5  7.9 cm for 5 cm mesh and 6 cm mesh, respectively. The equations of the selection curves for the two mesh sizes were obtained, and the probability of capturing individuals with length less than the established minimum of 15 cm was very low, amounting to 1.32% and 0.03% for the meshes of 5 cm and 6 cm, respectively. This information is of great value to maintain the stock of Atlantic thread-herring in Caponga Beach, CearÃ.
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