Population dynamics and feeding habit of Oreochromis niloticus and O. mossambicus in Siombak Tropical Coastal Lake, North Sumatra, Indonesia

Abstract

Abstract. Muhtadi A, Nur M, Latuconsina H, Hidayat T. 2021. Population dynamics and feeding habit of Oreochromis niloticus and O. mossambicus in Siombak Tropical Coastal Lake, North Sumatra, Indonesia. Biodiversitas 23: 151-159. Nile Tilapia (Oreochromis niloticus) and O. mossambicus (Mozambique Tilapia) are economically important fish species in Indonesia. This study aims to determine these two fish species' population dynamics, including growth, reproduction, recruitment, mortality rates, exploitation rates, and feeding habits. Samples were taken from September 2018 to August 2019 in Siombak Lake, North Sumatra Province. Data were analyzed in this study using software FISAT-II and Microsoft Excel. The results showed that Nile Tilapia had an isomeric growth pattern, and Mozambique Tilapia exhibited a negative allometric growth pattern. The estimate von Bertalanffy's growth parameters on ELEFAN-I were asymptotic length (L?) of Nile tilapia: 36.06 cm and Mozambique tilapia: 26.09 cm. The growth coefficient (K) of Nile tilapia was 0.59, and Mozambique tilapia was 0.54. The mortality rate (Z) of Nile tilapia reached 3.20 per year, and Mozambique tilapia reached 3.04 per year, whereas the natural mortality (M) of Nile Tilapia 1.24 while Mozambique Tilapia was 1.27. Based on the rate of exploitation, both fish have been overexploited. Peak spawning of Nile Tilapia was in August and December, and of Mozambique Tilapia was in March and June. Both species were omnivores, predominantly with herbivorous feeding habits.

Exploitation of striped snakehead (Channa striata) in Sempor Reservoir, Central Java, Indonesia: A proposed conservation strategy

“…The snakehead fish catch increased from 7327 tons to 16,528 tons during 200016,528 tons during to 200416,528 tons during (FAO 2005 and from 6490 tons to 21,987 tons during 2015 to 2019 (KKP 2020). Similar results have been observed for the economically important fish Siganus canaliculatus in Ambon Bay, which can reach maturity at the age of six months and has high mortality and exploitation rates (Latuconsina et al 2020(Latuconsina et al , 2022, as well as in tilapia in Siombak Tropical Coastal Lake, North Sumatra, Indonesia (Muhtadi et al 2022). High exploitation rate is the cause of low genetic variation in C. striata, as happened between central west Peninsular Malaysia and Malaysian Borneo populations implied anthropogenic activities (Tan et al 2012).…”

Parameters Estimation of Population Dynamic Tilapia Fish (Oreochromis Mossambicus) in Limboto Lake, Gorontalo Province, Indonesia

“…The age group of tilapia fish used the Bhattacharya method, the growth parameters used the Von Bertalanffy growth model, the natural mortality rate is calculated using Pauly's equation, the total mortality rate (Z) is calculated using the Beverton and Hold equation, and calculate yield per recruitment, the Beverton and Holt equations [15], [16], [17].…”

Evaluasi Pembenihan Ikan Nila (Oreochromis niloticus) di Instalasi Perikanan Budidaya, Kepanjen - Kabupaten Malang

“…Ikan nila (Oreochromis niloticus) tergolong ikan ominvora (memakan beragam jenis makanan), dengan makanan utamanya adalah fitoplankton (planktivora). Seperti yang ditemukan oleh Muhtadi et al [1] pada danau Siombak di Sumatera Utara, di mana ditemukan 7 kelompok makanan yang terdiri dari Chlorophyceae, Dinophyceae, Bacillariophyceae, Rotifera, Copepoda, Cladocera, dan Kepiting, dengan makanan utama sungai Nil Chlorophyceae (70%) dan Bacillariophyceae (24%). Di Indonesia, ikan nila (Oreochromis niloticus) termasuk spesies introduksi yang berasal dari daratan Cinta, namun sejak lama telah dikembangkan di Indonesia sebagai komoditas perikanan budidaya dan banyak diminati oleh masyarakat, sehingga menjadi salah satu komoditas perikanan di Indonesia, khususnya perikanan air tawar [2].…”