Detalhes bibliográficos
| Ano de defesa: |
2016 |
| Autor(a) principal: |
Silva, Sonja Luana Rezende
 |
| Orientador(a): |
Hirose, Gustavo Luis |
| Banca de defesa: |
Não Informado pela instituição |
| Tipo de documento: |
Dissertação
|
| Tipo de acesso: |
Acesso aberto |
| Idioma: |
por |
| Instituição de defesa: |
Universidade Federal de Sergipe
|
| Programa de Pós-Graduação: |
Pós-Graduação em Ecologia e Conservação
|
| Departamento: |
Não Informado pela instituição
|
| País: |
Brasil
|
| Palavras-chave em Português: |
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| Palavras-chave em Inglês: |
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| Área do conhecimento CNPq: |
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| Link de acesso: |
https://ri.ufs.br/handle/riufs/4469
|
Resumo: |
The present study evaluated the reproductive biology and growth of Xiphopenaeus kroyeri, Farfantepenaeus subtilis and Litopenaeus schmitti in the Continental Shelf of Sergipe state, from September 2013 to August 2014. Samplings occurred monthly in nine transects distributed at the depth of 5, 15 and 30 m, using a shrimp boat equipped with a "double rig" net. Environmental factors (water temperature and salinity, diameter and organic matter of the sediment) were also sampled monthly in each transect. The reproduction of females was determined by macroscopic observation of the gonads. For males, juveniles and adults were classified observing the petasma and the reproductive condition was associated with the presence of filled terminal ampoule. The reproductive and recruitment period were determined from the percentage of reproductive females and juveniles in relationship to the total number of sampled individuals by month. The relationship between the frequency of juveniles and reproductive females and environmental factors was tested by the Generalized Linear Model. The individual growth of males and females was estimated using the von Bertalanffy model and the longevity was estimated using its inverse formula. During the sampled period 6418 individuals of X. kroyeri, 1076 of F. subtilis and 504 of L. schmitti were analyzed. The sex ratio did not differ from expected (1:1) for X. kroyeri and L. schmitti, but females of F. subtilis were more abundant than males (χ2 = 4.97, p<0.05). All three species reproduced continuously during the year, with the peak of higher intensity for X. kroyeri from January to May/2014. For F. subtilis, peak of higher intensity occurred from September to November/2013 and from May to August/2014. For L. schmitti the higher intensity occurred from September to November/2013 and reproductive period with the lowest was from January to May/2014. The major intensities of recruitment were observed from September to December/2013 for X. kroyeri; from January to May/2014 for F. subtilis. The major and minor intensities of recruitment were observed, respectively, and from March to July/2014, and from October/2013 to January/2014 for L. schmitti. The temperature influenced the reproductive females of F. subtilis, and showed no effect in the reproduction of X. kroyeri and L. schmitti. The recruitment of X. kroyeri and L. schmitti was influenced by temperature, but the recruitment of F. subtilis was not influenced. Males (♂) of all three species exhibited higher coefficients of growth (k) and lower asymptotic length (CL∞ = carapace length) than females (♀): X. kroyeri (♂: CL∞ = 28.74 mm, k = 0.0081/day; ♀: CL∞ = 30.79 mm, k = 0.0058/day), F. subtilis (♂: CL∞ = 33.24 mm, k = 0,0063/day; ♀: CL∞ = 42.49 mm, k = 0.0059/day) and L. schmitti (♂: CL∞ = 32.48 mm, k = 0,0066/day; ♀: CL∞ = 38.78 mm, k = 0.0055/day). The longevity (years) estimated for X. kroyeri was 1.55 (♂) and 2.15 (♀), to F. subtilis was 2 (♂) and 2.12 (♀), and for L. schmitti 1.91 (♂) and 2.29 (♀).Therefore, other environmental factors, such as nutrient availability, during periods of larger rivers flow, may be influencing the reproduction of X. kroyeri and L. schmitti and the recruitment of F. subtilis in the sampled area, requiring further studies that could verify this influence. According to the results, the closed season corrently, based on recruitment, more adequate for L. schmitti and F. subtilis. Therefore, place it is suggested an adjustment in the second closed season include the months of September and October. Thus, the highest peak of to recruitment for X. kroyeri and of reproductive females for F. subtilis and L. schmitti. |
