Cakalang (Katsuwonus pelamis) merupakan ikan yang memiliki nilai ekonomis penting dan banyak tertangkap dengan huhate di perairan Laut Flores dan sekitarnya. Tujuan Penelitian adalah mengkaji beberapa aspek biologi ikan cakalang yang didaratkan di Pangkalan Pendaratan Ikan (PPI) Amagarapati dan unit pengolahan ikan (UPI) di Larantuka pada bulan Februari sampai Oktober 2015. Hasil penelitian menunjukkan ukuran panjang cagak berkisar antara 25 – 74 cm dengan modus pada nilai tengah 42 cm. Pola pertumbuhan bersifat alometrik positif dan nisbah kelamin jantan terhadap betina sebagai 1:1,14. Awal musim pemijahan berlangsung pada Februari-Maret dan Juli-Agustus. Ukuran pertama kali ikan tertangkap (Lc) pada panjang 48,8 cmFL lebih besar dengan panjang pertama kali matang gonad (Lm ) 41,1 cmFL, diduga perikanan cakalang di Larantuka mengarah pada recruitment overfishing. Kebiasaan makan ikan cakalang bersifat karnivora dengan komposisi 55,7% ikan tembang (Sardinella spp); 34,7% ikan teri (Stelophorus spp); 7,9% ikan layang (Decapterus spp); 0,9% cumi-cumi (loligo sp); 0,7% berupa hancuran ikan yang sudah tidak dapat diidentifikasi jenisnya dan sebesar 0,1%, berupa krustasea.Skipjack tuna (Katsuwonus pelamis) is one of caught by pole and line in Flores Sea and adjacent waters. Research was conducted to study biological aspects of skipjack tuna based on monthly catches landed at Amagarapati fishing port in Larantuka during February to October 2015. The results showed that fork length ranged from 25 to 74 cm with modus of 42 cm midlength. The growth pattern are alometric positive. The sex ratio of males to females was 1:1,14. The results showed that spawning seasons occured in February-March and July-October. Length at first capture (Lc) by pole and line was 48.8 cmFL and length at first maturity (Lm) was 41.1 cmFL, this condition indicated recruitment overfishing in its fisheries. Food habits of skipjack tuna are carnivorous with composition 55,7% Sardinella spp; 34,7% Stelophorus spp; 7,9% Decapterus spp; 0,9% Loligo sp; 0,7% flesh fish fragments that can’t be identified; and 0,1%, crustasea.

Abstract− Coral reefs are important because of their high biodiversity and their key role in the tropical marine biosphere. Furthermore, coral reefs are very valuable as a socioeconomic resource as they make important contributions to the gross domestic product of many countries. Thus, it is very important to monitor dynamic spatial distributions of coral reefs and related habitats dominated by coral rubble, dead coral, and bleached corals. Despite these natural and socio-economic advantages, many factors are threatening coral reefs. The study site was selected in Spermonde archipelago, South Sulawesi, Indonesia because this area is included in the Coral Triangle, recognized as the epicenter of coral diversity and a priority for conservation. Images of Landsat MSS, Landsat TM, Landsat ETM, Landsat ETM+, and Landsat 8 data were used to examine changes in the coral reefs of Suranti Island in the Spermonde Archipelago during forty one years from 1972 to 2013. The image processing includes gap fills, atmospheric corrections, geometric corrections, image composites, water column corrections, unsupervised classifications, and reclassifications. Fill Gap processing was done on Landsat ETM+ SLC-off. Subsequently, a multi-component change detection procedure was applied to define changes. Shallow water bottom types classification was divided into live coral, rubble and sand habitats, dead coral with algae, rubble, and sand. Preliminary results showed significant changes during the period 1972-2013 as well as changes in coral reefs, likely explained partly by destructive fishing practices.

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<p>Produksi krustasea di Cilacap menurun seiring dengan penurunan kualitas habitat. Fenomena ini dapat diungkap dengan penelitian stok krutasea dan kondisi habitatnya, untuk mengetahui; kelimpahan, laju tangkap, komposisi dan hubungannya dengan kondisi habitat. Penelitian dilakukan pada tahun 2013 dengan sampling pada area dan musim yang berbeda. Hasil penelitian mendapatkan kelimpahan krustasea di Area Timur (6.865 ekor/104m3) lebih tinggi dari Area Tengah (1.023 ekor/104m3) dan Area Barat (441 ekor/104m3), Musim Timur (4.378 ekor/104m3) lebih tinggi dari Musim Peralihan II (1.174 ekor/104m3). Laju tangkap krustasea di Area Timur (1.910 gr/jam) lebih tinggi dari Area Tengah (1.104 gr/jam) dan Area Barat (389 gr/jam), Musim Timur (1.222 gr/ jam) lebih tinggi dari Musim Peralihan II (1.046 gr/jam). Komposisi krustasea di Area Barat (71,50 %) lebih tinggi dari Area Tengah (67,66 %) dan Area Timur (50,68 %), Musim Timur (56,84 %) lebih rendah dari Musim Peralihan II (69,72 %). Kelimpahan larva udang di Area Tengah (70.313 ekor/ 103m3) lebih tinggi dari Area Barat (13.357 ekor/103m3) dan Area Timur (18.400 ekor/103m3), Musim Peralihan I (56.861 ekor/103m3) lebih tinggi dari Musim Timur (11.186 ekor/103m3). Kondisi perairan antar wilayah dan musim menunjukan kualitas yang berbeda. Oksigen dan karbondioksida terlarut lebih baik di Area Timur dibandingkan Area Barat dan Area Tengah. Kecerahan, salinitas dan kecepatan arus di Area Timur lebih tinggi dibandingkan area lainnya. Musim Peralihan I memiliki kandungan oksigen dan pH lebih baik dari Musim Timur, salinitas dan kecepatan arus lebih rendah dari Musim Timur. Larva udang lebih menyukai tutupan mangrove tinggi sedangkan juvenil lebih menyukai jenis mangrove Rhizopora spp.</p><p><br /><em>Crustaceans production in Cilacap decreases with habitat degradation. This phenomenon can be revealed by crutaceans stock krutasea and its habitat conditions, to know; abundance, catch rate, composition, and its relationship with habitat conditions. The study was conducted in 2013 by sampling in the area and the different seasons. The results of research to get the pace of crustaceans abundance in the East Area (6,865 individuals/104m3) is higher than Area Central (1,023 individuals/ 104m3) and the Western Area (441 individuals/104m3), East season (4,378 individuals/104m3) higher than the Transition II season (1,174 individuals/104m3). Catch rate of crustaceans in East Area (1,910 gr/hour) is higher than Area Middle (1,104 gr/hour) and the Western Area (389 gr/hour), East season (1,222 gr/hour) higher than the Transition II season (1,046 gr/hour). Composition crustaceans Area West (71.50%) is higher than the Central Area (67.66%) and the East Area (50.68%), East season (56.84%) was lower than Transition II season (69.72 %). The abundance of shrimp larvae in Area Central (70,313 individuals/103m3) higher than the Western Area (13,357 individuals/103m3) and East Area (18,400 individuals/103m3), Transition I season (56,861 individuals/ 103m3) is higher than East season (11,186 individuals/103m3). Water conditions between regions </em><em>and seasons show different qualities. Dissolved oxygen and carbon dioxide are better than the East Area and West Area Central Area. Transparanchy, salinity and speed of currents in the East Area is higher than other areas. Transitional I season have an dissolved oxygen and pH better than East season, salinity and speed of currents lower than East season. Shrimp larvae prefer the high mangrove cover while the juvenile prefers mangrove species Rhizophora spp.</em></p>

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