The relationship between the skipjack tuna (Katsuwonus pelamis
) fishery and seasonal temperature variability in the south-western Atlantic

Skipjack tuna, Katsuwonus pelamis (Linnaeus, 1758) is one of the most important species for Indonesian marine capture fisheries and is the third major species of capture fisheries in the world. This study aims to analyze the biometry of otolith (sagitta) of skipjack tuna caught with ‘soma pajeko’ (mini purse-seine) around FADs in the Sulawesi Sea. A total of 96 individuals of skipjack tuna measuring total length (TL) ranged between 232 and 625 mm and the average of TL was 419.64 mm (SD = 112.78 mm) were successfully taken otolith without defects. The length of otolith (OL) of the skipjack tuna ranged between 2.693 and 5.269 mm with an average of OL was 3.435 mm (SD = 0.602 mm). For both the size and shape indices of the otolith, there were no significant difference between the left and right otoliths for otolith length (OL), otolith perimeter (OP), Form-Factor (FF) and Roundness (Rnd), but asymmetric influences were very significance for otolith width (OW), otolith area (OA), Circularity (Cir), Rectangularity (Rec), Ellipticity (Ell) and Aspect Ratio (AR). There were no significant difference in the mean size and shape indices of the otolith between females and males. The relationship between TL - OL follows the power function: OL = 1.027993 * TL0.198863 (R2 = 13.18%). The low value of R2 seems to be due to the mixing of more than one stock of skipjack tuna in the sample. Separation of observation data in the relationship between TL - OL into two different stocks can increase the value of b or R2. It is possible for skipjack tuna in the Sulawesi Sea to consist of two different stocks. The separation of the two stocks can mainly be determined by the size of the otolith, the size of the otolith of stock 1 is relatively large compared to stock 2. The relationship of ln (TL) - ln (OL) stock 1 and stock 2 were ln (OL) = -2,282 + 0,610 * ln (TL) (n = 53; r = 0.91) and ln (OL) = -2,363 + 0.566 * ln (TL) (n = 43; r = 0.64). It is possible that stock 1 is the stock of the Indian Ocean and stock 2 is the stock of the Western Pacific Ocean. To test this hypothesis, genetic studies are needed.Keywords: otolith biometry, stock separation, Katsuwonus pelamis, Sulawesi SeaABSTRAKIkan cakalang, Katsuwonus pelamis (Linnaeus, 1758) merupakan salah satu spesies yang sangat penting untuk perikanan tangkap laut Indonesia dan merupakan spesies utama urutan ke-3 perikanan tangkap dunia. Penelitian ini bertujuan untuk menganalisis biometri otolit (sagitta) ikan cakalang yang tertangkap dengan ‘soma pajeko’ (mini purse-seine) di sekitar rumpon di Laut Sulawesi. Sejumlah 96 individu ikan cakalang berukuran panjang total (TL) 232 - 625 mm dan rata-rata TL 419,64 mm (SD = 112,78 mm) berhasil diambil otolitnya tanpa cacat. Otolit (kiri) ikan cakalang tersebut berukuran panjang (OL) 2,693 - 5,269 mm dengan rata-rata OL 3,435 mm (SD = 0,602 mm). Baik untuk ukuran maupun indeks bentuk otolit, tidak terdapat perbedaan yang nyata antara otolit kiri dan kanan untuk panjang otolit (OL), keliling otolit (OP), Form-Factor (FF) dan Roundness (Rnd), tetapi pengaruh asimetris untuk lebar otolit (OW), luas otolit (OA), Circularity (Cir), Rectangularity (Rec), Ellipticity (Ell) dan Aspect Ratio (AR) sangat nyata. Tidak terdapat perbedaan yang nyata rata-rata ukuran maupun indeks bentuk otolit antara betina dan jantan. Hubungan TL - OL mengikuti fungsi perpangkatan: OL = 1,027993*TL0,198863 (R2 = 13,18%). Rendahnya nilai R2 ini nampaknya disebabkan karena bercampurnya lebih dari satu stok ikan cakalang dalam sampel. Pemisahan data amatan dalam hubungan TL – OL menjadi dua stok yang berbeda dapat menaikkan nilai b maupun R2. Ikan cakalang yang terdapat di Laut Sulawesi ada kemungkinan terdiri dari dua stok yang berbeda. Pemisahan kedua stok tersebut terutama dapat ditentukan lewat ukuran otolitnya, stok 1 berukuran otolit relatif besar dibandingkan dengan stok 2. Hubungan ln(TL) – ln(OL) stok 1 dan stok 2 berturut-turut adalah ln(OL) = -2,282 + 0,610*ln(TL) (n = 53; r = 0,91) dan ln(OL) = -2,363 + 0,566*ln(TL) (n = 43; r = 0,64). Ada kemungkinan stok 1 merupakan stok Samudra Hindia dan stok 2 merupakan stok Samudra Pasifik Barat. Untuk menguji hipotesis ini diperlukan kajian secara genetik.Kata kunci: biometri otolit, pemisahan stok, Katsuwonus pelamis, Laut Sulawesi

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Operational oceanography applied to skipjack tuna (Katsuwonus pelamis) habitat monitoring and fishing in south‐western Atlantic

Fisheries Oceanography ◽

10.1111/fog.12388 ◽

2018 ◽

Vol 28 (1) ◽

pp. 82-93 ◽

Cited By ~ 2

Author(s):

Juliano Lauser Coletto ◽

Marcelo Peres Pinho ◽

Lauro Saint Pastous Madureira

Keyword(s):

Skipjack Tuna ◽

Katsuwonus Pelamis ◽

Western Atlantic ◽

Habitat Monitoring ◽

Operational Oceanography

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The relationship between multi-sensor satellite data and Bayesian estimates for skipjack tuna catches in the South Brazil Bight

International Journal of Remote Sensing ◽

10.1080/01431160903198538 ◽

2010 ◽

Vol 31 (15) ◽

pp. 4049-4067 ◽

Cited By ~ 5

Author(s):

Fabrício Sanguinetti Cruz de Oliveira ◽

Douglas Francisco Marcolino Gherardi ◽

José Luiz Stech

Keyword(s):

Satellite Data ◽

Skipjack Tuna ◽

The South ◽

Bayesian Estimates ◽

The Relationship ◽

South Brazil

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The relationship between the boundary layer moisture transport from the South China Sea and heavy rainfall over Taiwan

Terrestrial Atmospheric and Oceanic Sciences ◽

10.3319/tao.2019.07.01.01 ◽

2020 ◽

Vol 31 (2) ◽

pp. 159-176 ◽

Cited By ~ 1

Author(s):

Chuan-Chi Tu ◽

Yi-Leng Chen ◽

Pay-Liam Lin ◽

Po-Hsiung Lin

Keyword(s):

Boundary Layer ◽

South China Sea ◽

South China ◽

Moisture Transport ◽

Heavy Rainfall ◽

The South China Sea ◽

The South ◽

China Sea ◽

The Relationship

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A RESSIGNIFICAÇÃO DA POBREZA MUNDIAL: NOVAS FORMAS DE TRATAMENTO

Confluências | Revista Interdisciplinar de Sociologia e Direito ◽

10.22409/conflu18i1.p20281 ◽

2017 ◽

Vol 18 (1) ◽

pp. 04

Author(s):

Tatiani De Azevedo Lobo ◽

Marli M. Moraes Da Costa

Keyword(s):

Social Indicators ◽

Academic Research ◽

Specific Treatment ◽

Capital Social ◽

The South ◽

Sharp Rise ◽

Contemporary Debate ◽

The World ◽

Relationship Network ◽

The Relationship

Resumo: O presente ensaio busca apresentar e fomentar algumas questões pertinentes ao debate contemporâneo sobre a pobreza, demonstrando a importância do tema no cenário mundial. Para tanto, inicialmente discorre-se sobre a construção histórico-social da pobreza e suas características contemporâneas. Com efeito, aponta-se a limitação dos fatores tradicionalmente apresentados como causadores da pobreza, como cultura, genética, geografia etc. Além disso, apresentam-se as formas atuais de monitorar o fenômeno, como o coeficiente de Gini e o IDH. Posteriormente, aborda-se a distribuição mundial da pobreza. Nesse ponto, colaciona-se que a pobreza é um problema mundial. No entanto, é perceptível que o Sul ainda concentra maior número de indivíduos pobres do que o Norte. Na esteira dos últimos dados da pesquisa realizada pelas Nações Unidas, houve uma nítida ascensão do Sul, especialmente nos indicadores sociais ligados à educação. A seguir, trata-se do capital social e da Teoria das Capacidades, apresentando-se novas abordagens da pobreza. Assim, o capital social trata de uma ideia utilizada para verificar a rede de relacionamento dos indivíduos. Já a Teoria das Capacidades está ligada com a ideia de oportunidade da liberdade. Por fim, estuda-se as políticas públicas, bem como seu aspecto fragmentário. Conclui-se, assim, sobre a necessidade de implementação de políticas públicas elaboradas sob a égide de novos paradigmas, a fim de possibilitar o tratamento específico do fenômeno da pobreza, conforme as peculiaridades de cada local. Para tanto foi utilizado neste trabalho o método de abordagem hipotético-dedutivo, o método de procedimento monográfico e a técnica de pesquisa, operacionalizados por meio do emprego de vasta pesquisa bibliográfica. Abstract: This essay seeks to provide and foster some relevant to the contemporary debate on poverty issues, demonstrating the importance of the issue on the world stage. For this purpose, initially spoke about the historical and social construction of poverty and its contemporary features. Indeed, he pointed out the limitation of the factors traditionally presented as the cause of poverty, as a culture, genetics, geography, etc. Furthermore, we presented the current ways of monitoring the phenomenon, such as the Gini coefficient and the HDI. Subsequently addressed the global distribution of poverty. At this point, if collated that poverty is a worldwide problem. However, it is apparent that the South still more concentrated than the poor North individuals. In the wake of recent data from research conducted by the United Nations, there was a sharp rise in the South, especially in social indicators related to education. Next, we treated the capital and the Theory of Capabilities, presenting new approaches to poverty. Thus, social capital is an idea used to verify the relationship network of individuals. Already Capabilities Theory is linked with the idea of freedom of opportunity. Finally, we studied public policy, as well as its fragmentary appearance. Thus, it is concluded on the need to implement public policies prepared under the aegis of new paradigms to enable specific treatment of the phenomenon of poverty, according to the peculiarities of each site. For that was used in this work the method of hypothetical-deductive approach, the method of procedure and the monographic research technique, operationalized through the use of extensive academic research.

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