Reproductive biology climbing perch Anabas testudineus (Bloch 1792) at Danau Tempe Kabupaten Wajo South Sulawesi

Abstract

The high exploitation pressure and decreasing environmental conditions of Lake Tempe due to pollution, sedimentation, growth of aquatic weeds, and the presence of invasive alien fish, namely suckermouth catfish, are thought to have harmed one of the native fish, namely climbing perch (Anabas testudineus). The research aims to analyze the reproductive biology of climbing perch. Fish were caught using gill nets from January to April 2021. The total length of the fish was measured using a caliper (cm), and the weight (g) was measured using an analytical balance. Fish gonads were preserved in a 4% formalin solution. Fish fecundity was calculated based on the gravimetric method. The length distribution of male and female fish was 7.5 - 15.5 and 7.5 - 17.5 cm, respectively. The maximum climbing perch caught was 17.5 cm smaller than the maximum length ever caught, which was 35.0 cm, and the average size was 9.56 cm smaller than the average length of climbing perch, which was 12.5 cm. The ratio of male and female fish as a whole was 1.1: 0.9 or 53%: 47%, while the sex ratio of males and females in spawning was 38%: 62%. Climbing perch is polygamous, i.e., male fish have several partners in one spawning season. The spawning season lasted throughout the research period, with the spawning season's peak in February with a total spawner pattern. Fecundity ranged from 253-10,237 eggs with an average value of 2,571 eggs, and the relationship between length and weight with fecundity was very strong. The growth pattern of male and female fish was negative allometric.

Abstrak

Tekanan eksploitasi yang tinggi dan kondisi lingkungan Danau Tempe yang semakin menurun akibat pencemaran, sedimentasi, pertumbuhan gulma air, dan hadirnya ikan asing invasif, yaitu ikan sapu-sapu, diduga telah memberikan pengaruh buruk terhadap salah satu ikan asli yaitu ikan betok (Anabas testudineus). Penelitian bertujuan untuk menganalisis kondisi biologi reproduksi ikan betok. Ikan sampel ditangkap menggunakan jaring insang dari Januari-April 2021. Panjang total ikan diukur dengan jangka sorong (cm) dan bobot ditimbang (g) dengan timbangan analitik. Gonad ikan diawetkan dalam larutan formalin 4%. Fekunditas ikan dihitung berdasarkan metode gravimetrik. Sebaran ukuran panjang ikan jantan dan betina masing-masing 7,5 - 15,5 dan 7,5 - 17,5 cm. Panjang maksimum ikan betok yang tertangkap yaitu 17,5 cm lebih kecil dari panjang maksimum yang pernah tertangkap yaitu 35,0 cm, dan panjang rata-rata yaitu 9,56 cm lebih kecil dari panjang rata-rata ikan betok yaitu 12,5 cm. Nisbah ikan jantan dan betina secara keseluruhan sebesar 1,1 : 0,9 atau 53% : 47%; sedangkan nisbah kelamin jantan dan betina dalam pemijahan yaitu 38% : 62%. Ikan betok bersifat poligami yakni ikan jantan memiliki beberapa pasangan dalam satu musim pemijahan. Musim pemijahan berlangsung sepanjang bulan penelitian dengan puncak musim pemijahan pada Februari dengan pola pemijah serentak. Fekunditas berkisar antara 253- 10.237 telur dengan nilai rata-rata 2.571 telur. Hubungan panjang dan bobot dengan fekunditas sangat kuat.Pola pertumbuhan ikan jantan dan betina adalah allometrik negatif.