White Shrimp Population Dynamic in Riau Province: the Effects of Intrinsic Growth Rate and Effort

Fisheries management at Indonesia during the time is relatively responsive to unsustainable management.This caused by this management which is not yet considering population dynamic aspects, such as intrinsicgrowth rate, catch ability of fishing gears and carrying capacity. The objectives of these researches are todevelop and decide of the intrinsic growth rate and catch effort effects to white shrimp population dynamicat Riau Province. Modeling was conducted to growth and harvesting model with numerical simulationtechnique. The result of numerical simulation represents that intrinsic growth rate of white shrimp is equal0.88 tons/years and carrying capacity is equal 38,023.26 tons. Existence standard effort 54,447 trips/yearscause decreasing maximum population growth became 10,941 tons of population with growth rate 2,831.3tons. The optimal and sustainable management of white shrimp fisheries at Riau Province must be considerpopulation dynamic aspects

Analisis Keterkaitan Parameter Oseanografi Terhadap Upaya Penangkapan Ikan Tenggiri (Scomberomorus comerson) yang Didaratkan Di PPN Kejawanan Cirebon

Kegiatan perikanan tangkap adalah kegiatan ekonomi yang mencakup penangkapan atau pengumpulan hewan dan tanaman air yang hidup di laut atau perairan umum secara bebas. Salah satu daerah sentra perikanan tangkap adalah Cirebon. Produksi perikanan yang cukup tinggi di dominasi oleh perikanan tangkap di laut. Tujuan dari penelitian ini adalah untuk mengetahui hubungan parameter oseanografi terhadap upaya penangkapan ikan. Penelitian ini dilakukan di perairan Cirebon dan Pelabuhan Perikanan Kejawanan dengan melihat hubungan suhu permukaan laut, klorofil-a dan Catch Per Unit Effort (CPUE). Hasil dari penelitian ini menunjukkan bahwa perairan Laut Jawa memiliki variabilitas. Nilai faktor oseanografi yaitu Suhu Permukaan Laut (SPL) dan Klorofil-a. Rata-rata nilai SPL pada bulan Agustus hingga Desember terus mengalami peningkatan. Nilai rata-rata konsentrasi klorofil-a tinggi pada bulan Agustus hingga Desember. Dengan demikian Ikan Tenggiri yang didaratkan di PPN Kejawana Cirebon mempunyai keunikan yaitu musim tangkapan yang dilakukan dalam 1 tahun yaitu 5 bulan, Agustus hingga Desember. Nilai hasil tangkapan ikan tenggiri tertinggi berada pada bulan Oktober yaitu sebesar 650 kg dan terendah terjadi pada bulan September yaitu 146 kg. nilai R square sebesar 0,926 yang menunjukan bahwa keeratan hubungan linear antara variabel (X) dan variabel (Y) yaitu sebesar 92,6%, sedangkan sisanya yaitu 7,4% dipengaruhi oleh variabel lain di luar variabel perhitungan

Analysis of Genetic Diversity of Mobula sp. in Cilacap Using RAPD (Random Amplified Polymorphic DNA) Markers

Devil rays (Mobula sp.) are in an endangered status, so conservation measures are needed. One of the first steps is to identify the level of genetic diversity. This study aims to determine the genetic diversity of mobula in Cilacap based on DNA bands of RAPD (Random Amplified Polymorphic DNA) polymorphism genetic markers. This research was conducted in September 2021 – June 2022. Sampling was carried out at PPS Cilacap and molecular analysis was carried out at the Biotechnology Laboratory building 3, Faculty of Fisheries and Marine Sciences, Padjadjaran University. The research procedure began with preservation of the devil rays (Mobula sp.) sample, isolation of sample DNA, electrophoresis of isolated DNA results, calculating DNA purity, DNA amplification, electrophoresis of DNA amplification results, and data processing and analysis. DNA isolation was carried out using the Promega Kit method. The electrophoretic results of DNA isolation from the three mobula rays samples showed quite good results. Band samples CIL 10 and CIL 9 looked thick and did not smear, while C13 produced bands and there was a visible smear. The results of calculating the purity of DNA isolated from mobula rays CIL 9, CIL 10, CIL 13 have a purity value of 1.94, 1.96, 1.80. Results The highest concentration of DNA was CIL-13 sample with a value of 452.90 ng/μL while the lowest concentration was CIL-10 which was 419.90 OPE-01 resulting in 10 out of 20 visualized polymorphic bands. The similarity index of CIL-9 to CIL-10 in the OPE-01 primer was 40% while the similarity index of CIL-9 and CIL 10 to CIL-13 was 35%. The average similarity index shows that the genetic diversity of the Mobula species is moderate. Morphologically, CIL-09 is a species of Mobula thrustoni, CIL 10 is a species of Mobula mobular, and CIL-13 is a species of Mobula tarapacana. CIL-9 (M. thrustoni) has a closer similarity index to CIL-10 (M. mobular) than CIL-13 (M. tarapacana). OPE-01 primer is good for analyzing diversity in mobula rays (Mobula sp.). OPE-01 has 10 out of 20 visualized polymorphic bands

Hanging Ratio Gillnets on Different Mesh Sizes for Mackerel (Scomberomorus commerson): A Case of Pangandaran Regency, Indonesia

Gillnet is a simple fishing gear that is widely used by fishermen in Pangandaran Regency. This study aims to determine the classification calculation of the value of hanging ratio gillnet and the catch of mackerel (Scomberomorus commerson) with different mesh sizes. This research was conducted in January 2019 in Pangandaran Regency, Indonesia. The method used in this research is the survey method. Gillnet used has 2 types of mesh sizes, 3,5 and 4 inch gill nets with each net length of 650 meters (7,312 mesh) and 750 meters (7,384 mesh). Gillnet has 12 meters with a net mesh size of 3,5 inches as many as 135 mesh and a 4 inch mesh size of 118 mesh. Hanging ratio for 3.5 inch gillnet is 0,56 while for mesh size 4 inch is 0,54. Based on these results, it can be concluded that the gill nets are selective. The proportion of catch results shows the number of target fish gill nets with a 3,5 inch mesh size is 20% and bycatch is 80%. The proportion of gillnet catches with a 4 inch mesh size shows main catch of 35,2% while the bycatch proportion is 64.8%