UKURAN PERTAMA KALI MATANG GONAD DAN SELEKTIVITAS JARING INSANG IKAN NILA (Oreochromis niloticus) DI WADUK JATILUHUR, JAWA BARAT

Abstract

A gillnet is a common fishing gear for exploitation and fish capture at Jatiluhur Reservoir. The fish size captured by the gillnet depends on the mesh size for its selective fishing gear. Determination of gillnet mesh size is one of effort for fisheries management. The management of nile tilapia (Oreochromis niloticus) is based on gillnet selectivity and reproductive biology of nile tilapia. The aim of the research was to estimate length at the first mature (Lm) and gillnet selectivity for nile tilapia. The research was conducted at February-September 2017 through experimental fishing using gillnet with 1.0–4.0 mesh size (interval 0.5 inch). The gillnet installation was performed at six stations, namely Cihuni-Cibadak, Sungai Cikanyayan, Sungai Ciririp, Sungai Cihonje, Pasir Kole and Cilalawi. The Lm of nile tilapia was 18.3 and 23.3 cm for female and male, respectively. The total length retained in the gillnet with the highest probability for mesh size 1.0; 1.5; 2.0; 2.5; 3.0; 3.5 and 4.0 inches were 9.5; 12.5; 14.5; 18.5; 20.5; 26.5 and 30.5 cm, respectively. The minimum mesh size used for nile tilapia exploitation was ≥3 inches because it was able to catch nile tilapia with the total length larger than Lm (Lc>Lm) and with an SPR value of > 40% so that the tilapia resource in the Jatiluhur Reservoir remains sustainable.

Environment-friendly floating net cage culture research in Indonesia

“…Hydroponic plants use water spinach, and artificial wetland plants use vetiver. After the phytoremediation, components flow into a physical filter consisting of layers of limestone, sand, and palm fiber [24,25]. Water spinach was chosen because it grows fast and can reduce nitrite by 88.15%, nitrate by 69.49%, phosphate by 48.38%, and organic matter by 42.86% ]26].…”

Pengelolaan Sumber Daya Ikan Corencang (Cyclocheilichthys apogon) Berdasarkan Aspek Biologi Ikan dan Selektivitas Alat Tangkap

“…Aspek biologi, ekonomi, dan kelestarian sumber daya merupakan faktor yang dipertimbangkan dalam eksploitasi sumber daya ikan (Kronbak et al, 2009). Penelitian mengenai selektivitas jaring insang dan aspek biologi masih dilakukan secara terpisah, kecuali untuk ikan Nila (Warsa et al, 2019a). Penelitian yang telah dilakukan mengenai selektivitas jaring insang untuk jenis-jenis ikan di Waduk Jatiluhur antara lain selektivitas jaring insang ikan Tawes (Barbonynus gonionotus) (Purnomo, 1987) dan ikan Hampal .…”

A biological perspective for the fishery management of a small urban lake in Indonesia: a case study on the reproductive stage of the red devil (Amphilopus citrinellus) in Situ Cilodong, West Java, Indonesia

“…There has been various research on the reproductive biology of the red devil in Indonesia; for examples: Jatiluhur reservoir (Purnamaningtyas & Tjahjo, 2010), Situ Panjalu (Warsa & Purnomo, 2013), Kedung Ombo Reservoir (Adjie & Fatah, 2015), Lake Sentani (Ohee et al, 2020), Sangiran Reservoir (Santoso, 2019), and Sermo Reservoir (Hedianto, 2023). Nevertheless, those studies did not provide a histological assessment of the fish's gonad development.…”