Judul: The use of Shrimp Waste as Artificial Bait in Trap Fishing Operation
Abstrak: Nelayan bubu di Pulau Panggang masih menggunakan berbagai macam umpan (ikan rucah, bulu babi dan bintang laut) dengan sistem try and error untuk memikat ikan masuk ke dalam bubu, namun hasilnya belum memuaskan. Limbah udang menjadi alternatif umpan dalam pengoperasian bubu. Penelitian ini bertujuan mendeskripsikan komposisi hasil tangkapan bubu tambun dengan umpan limbah udang, menentukan pengaruh umpan buatan dari limbah udang terhadap jumlah tangkapan serta menghitung efektivitas penangkapan ikan target menggunakan umpan buatan limbah udang. Penelitian menggunakan metode experimental fishing menggunakan 6 unit bubu tambun dengan 3 perlakuan yaitu bubu dengan umpan limbah udang, ikan rucah, dan bubu tanpa umpan. Tiga unit bubu dengan umpan limbah udang, ikan rucah dan tanpa umpan dioperasikan sekaligus dalam suatu perairan serta 3 unit bubu lainnya dioperasikan pada perairan yang berbeda. Hasil penelitian menunjukkan bahwa bubu tambun menggunakan limbah udang paling efektif dibandingkan umpan dari ikan rucah dan tanpa umpan. Namun, penggunaan umpan ikan rucah lebih efektif dibandingkan dengan bubu tanpa umpan untuk menangkap ikan. Hasil tangkapan utama bubu di Pulau Panggang Kepulauan Seribu tercatat 526 ekor (68,58%) dan hasil tangkapan sampingan sebanyak 241ekor (31,42%). Selain itu, umpan buatan dari limbah udang berpengaruh signifikan terhadap jumlah hasil tangkapan bubu di perairan Pulau Panggang Kepulauan Seribu., Trap fishers in panggang Island have used various kinds of bait with a try and error system to catch fish, but the catch results were not satisfactory. Shrimp waste can be used as an alternative bait in trap fishing operations. The research aims to describe the composition of the trap catches with shrimp waste bait, determine the effect of shrimp waste bait on the number of trap catches, and calculate the effectiveness of fish targets using shrimp waste bait. The study used an experimental fishing method with six traps with three bait treatments: shrimp waste bait, trash fish bait, and no bait, as the control treatment. The three traps are operated simultaneously in a fishing ground, and the other three are operated in different fishing ground. The results showed that the shrimp waste baits trap was the most effective than trash fish baits and without baits. However, trash fish baits are more effective than no baits. The main catch of traps in Panggang Island’s water was recorded at 526 fish (68.58%) and by-catch at 241 fish (31.42%). In conclution, shrimp waste bait has a significant effect on the number of traps caught.
Keyword: traps, main catches, by catches, shrimp waste bait, artificial bait

Judul: The Use of Trash Fish Diluted with Squid (Loligo spp.) Bait on Bottom Gillnet in Palabuhanratu Bay
Abstrak: Perikanan jaring rampus saat ini belum mengalami banyak kemajuan dan hasil tangkapannya yang tidak selalu meningkat. Penelitian ini bertujuan untuk membandingkan komposisi hasil tangkapan jaring rampus berumpan ikan rucah yang dilarutkan cumi dengan jaring rampus tanpa umpan, menentukan pengaruh penggunaan umpan, dan menentukan produktivitas jaring rampus perlakuan dan kontrol. Penelitian dilakukan di Teluk Palabuhanratu, Kabupaten Sukabumi, menggunakan metode eksperimental fishing dengan mengikuti operasi penangkapan selama 16 trip. Hasil tangkapan pada piece jaring rampus perlakuan sebesar 69,83 kg dan piece kontrol sebesar 42,93 kg dengan rata-rata jumlah jenis ikan pada piece perlakuan yaitu 8  0,47 sedangkan kontrol yaitu 7  0,45. Hasil tangkapan dominan pada penelitian ini adalah swanggi (Priacanthus tayenus), gulamah (Johnius trachycephalus), layang anggur (Decapterus kurroides), selar bentong (Selar crumenophthalmus), dan kakap (Lates calcarifer). Perlakuan menggunakan umpan ikan rucah yang dilarutkan cumi memberikan pengaruh nyata terhadap berat total dan jumlah ekor hasil tangkapan. Penggunaan umpan membantu kenaikan persentase produktivitas piece jaring rampus perlakuan sebesar 62,7% dengan produktivitas per-piece perlakuan lebih besar dibandingkan kontrol dengan masing-masing nilainya sebesar 1,09 kg/piece dan 0,67 kg/piece dan untuk nilai produktivitas satu piece perlakuan yaitu Rp19.181,00 sedangkan kontrol yaitu Rp6946,00 sehingga didapatkan persentase produktivitas hasil tangkapan piece perlakuan terhadap piece kontrol sebesar 176,1%., Currently, bottom gillnet fishing has not made much development, and its catches are not always increasing. This study aimed to compare the composition of the catch bottom gillnet with trash fish diluted squid bait and without bait, determine the effect of bait use, and determine the productivity of treatment and control bottom gillnet. The research was conducted in Palabuhanratu Bay, Sukabumi Regency, using experimental fishing methods by following fishing operations for 16 trips. The catch on the treated piece was 69,83 kg, and the control piece was 42,93 kg, with the average number of fish species in the treated piece was 8  0,47 while the control was 7  0,45. The dominant catches in this study were bigeye bullseye (Priacanthus tayenus), leaf tail croaker (Johnius trachycephalus), redtail scad (Decapterus kurroides), bigeye scad (Selar crumenophthalmus), and snapper (Lates calcarifer). Trash fish diluted squid bait significantly affected the total weight and number of fish caught. The use of bait helped to increase the percentage of productivity of treated net pieces by 62,7%, with productivity per treated piece more significant than the control with a value of 1,09 kg/piece and 0,67 kg/piece. The productivity value of one piece of treated was Rp19.181,00 while the control was Rp6946,00, so the percentage of productivity of the treated piece catch against the control piece was 176,1%.
Keyword: bait attractor, bottom gillnet, Palabuhanratu Bay, squid, trash fish

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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