Stingray (Batoidea) are often caught as bycatch in south coast of Prigi waters. The stingray resource has very limited in number and require a long time to reproduce. Attention must be paid to avoid the extinct of stingray resource. This research aimed to justify species composition and identify length weight relationship, sex ratio, and clasper maturity level of stingray (Batoidea) caught in south coast of Prigi waters. The research was carried out from December 2019 to April 2020 at Prigi archipelago fishing port as landing place. This study used a quantitative descriptive method with the number of samples that were successfully obtained as many as 97 stingray. During the study, 6 species of stingray (Batoidea) were identified, namely Taiwan guitarfish (Rhinobatos schlegelii), blotched fantail stingray (Taeniurops meyeni), Japanese devilray (Mobula japanica), bluespotted maskray (Neotrygon kuhlii), shark ray (Rhina ancylostoma), dan bluespotted fantail ray (Taeniura lymma). Result indicated that Taiwan guitarfish (R. schlegelii) and bluespotted maskray (N. kuhlii) were two dominant stingray species in south coast of Prigi waters with proportion of 47.42% and 41.24% respectively. Disk width (Dw) and weight (W) of Taiwan guitarfish (R. schlegelii) ranged from 15.2 cm to 24.6 cm and from 268 gr to 1060 gr respectively and bluespotted maskray (N. kuhlii) ranged from 17.3 cm to 39.3 cm and from 140 gr to 2006 gr respectively. Another analysis showed that Taiwan guitarfish (R. schlegelii) and bluespotted maskray (N. kuhlii) had length weight relationship equations W = 0.0202 Dw34699 and W=0.0351*Dw29848 respectively. The sex ratio of Taiwan guitarfish Taiwan guitarfish (R. schlegelii) dan bluespotted maskray (N. kuhlii) was 1:1.4 and 1:1.2 respectively. In addition, clasper maturity level of the Taiwan guitarfish (R. schlegelii) and bluespotted maskray (N. kuhlii) species was dominated by Non-Calcification (NC). In conclusion, The stingray (Batoidea) caught in south coast of Prigi waters were dominated by Taiwan guitarfish (R. schlegelii) and bluespotted maskray (N. kuhlii). Length weight relationship of Taiwan guitarfish (R. schlegelii) and bluespotted maskray (N. kuhlii) was allometric positive and isometric respectively. Both of them was in balance condition sex ratio and was dominated by immature stage. Hence fishing activities in south coast of Prigi waters should avoid the stingray as bycatch in order to preserve the stock.

Penelitian modifikasi konstruksi trammel net dilakukan dengan melakukan uji coba penangkapan di perairan Lontar, Serang. Tiga konstruksi trammel net yang diujicoba, yaitu trammel net kontrol (TK), trammel net perlakuan 1 (TP1) dan trammel net perlakuan (TP2). TK adalah trammel net yang memiliki 2 lembar jaring lapis luar dan kekendurannya menumpuk di bagian bawah. Selanjutnya TP1 adalah trammel net yang memiliki 1 lembar jaring lapis luar dan membentuk 1 kantong di bagian bawah, sedangkan TP2 memiliki 1 lembar jaring lapis luar dan membentuk 2 kantong. Hasil uji coba menunjukkan ketiga konstruksi trammel net menghasilkan 10 jenis organisme yang sama, yaitu Penaeus merguiensis, Harpiosquilla raphidea, Portunus pelagicus, Argyrosomus amoyensis, Pseudorhombus arsius, Platycephalus indicus, Pomadasys maculatus, Himantura uarnak, Leiognathus equulus, Thryssa hamiltonii. TP2 menangkap 1.165 individu, atau lebih banyak 1.29 kali dibandingkan dengan TP1 (897 individu) dan 2.36 kali dibandingkan dengan TK (493 individu). Hasil uji statistik menggunakan ANOVA dan uji BNT juga menunjukkan bahwa modifikasi konstruksi trammel net terbukti dapat meningkatkan jumlah hasil tangkapan (F39.99: α0.05).

Bubu merupakan alat tangkappaling memungkinkan untuk penangkapan ikan hias karang, selain itu alat tangkap inimempunyyai kelebihan selektif untuk spesies dan ukuran, hasil tangkapan berkualitas dan hidup, dampak terhadap lingkungan kecil, mudah dalam penyediaan bahan baku, serta murah. Namun diisisi lain sering terjadikegagalan saat pengoperasian, sebagai akibat hempasan arus dasar laut yang menyebabkan posisi bubu terbalik. Melalui rekayasa bubu lipat multifunnel, diharapkan menjadi solusi permasalahan-permasalahan yang ada saat ini. Tujuan penelitian ini adalah merekayasa bubu lipat multifunnel,menghitung nilai hidrostatis serta uji coba penangkapan. Metode yang digunakan adalah deskriptif kuantitatif dan ekperimental fishing. Bagian bubu lipat terdiri dari rangka besi, badan jaring, mulut bubu, tempat umpan serta pintu hasil tangkapan. Bubu didesain mempunyai enam mulut pada bagian sisi samping, bagian rangka hanya terdapat pada sisi atas dan bawahnya saja. Proses terbukanya bubu ketika dalam air karena adanya gaya apung pada rangka atas yang lebih besar dibandingkan gaya tenggelam pada rangka bawah, dan perbandingan gaya total antara rangka atas dan bawah lebih besargaya tenggelam. Besar gaya pada rangka atas -0,2344 kgf, rangka bawah 2,2753 kgf dan gaya total bubu sebesar 2,0409 kgf. Uji coba penangkapan memperoleh ikan kerapu, ikan kakatua dan morai.

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Sharks are often found in all the waters are scattered in various regions of the world. On the other hand, shark fisheries have declined globally due to shark fishing as well as the demand is very high. Thus, vital information regarding the length-weight relationship is essential in the management and protection of shark fishery resources. Data collection was carried out from December 2019 to March 2020 by way of direct observation, interviews by recording almost all shark catches landed by bottom longlines or drift longlines. Results for the study found 28 species, with four species of sharks that have the highest number that is Galeocerdo Cuvier 17%, Sphyrna lewini 16%, 16% Atelomycterus marmoratus, and Carcharhinus melanopterus 12%. The length-frequency distribution for Galeocerdo cuvier distributed between 148-437 cm in Sphyrna lewini distributed between 109-308 cm, Atelomycterus marmoratus is distributed between 39-68 cm, and Carcharhinus melanopterus is distributed between 49 - 204 cm. The length-weight relationship between Galeocerdo cuvier and Sphyrna lewini is allometric negative, whereas Atelomycterus marmoratus, and Carcharhinus melanopterus are isometric.