Some Reproductive Biology Studies of Rabbitfish Siganus canaliculatus (Park, 1797) from the Southern Coastal Waters of Jeneponto, South Sulawesi, Indonesia

Abstract

The rabbitfish Siganus canaliculatus population has been exploited intensively in the Jeneponto Regency South Sulawesi by fishermen used non selective fishing gear, throughout the year even the spawning season. The intensive fishing without management policy can caused decreasing of the rabbit fish population, and if it continues population will be collapse. This study was conducted to investigate some of the reproductive biological study of this species. A total of 1821 specimens of S. canaliculatus consisting of 1436 males and 385 females were randomly collected on a monthly from fishers in the coastal waters of the Jeneponto, South Sulawesi. The fecundity and gonad stage were studied for 39 female individuals varied between 85 and 284 mm total length (TL). Egg diameters were determined using the microscope. The overall sex ratio (Males: Females) ranged from 1.7: 1 to 8.2:1 The estimation of fecundity was between 5416 and 130760 eggs.ind-1, and increased with fish length, body weight and gonad weight. Egg diameter of S. canaliculatus in this study ranged from 0.1-0.5 of stage III. 0.35-0.45 of stage IV, 0.1-0.55 of stage V, and 0.35-0.55 of stage VI. Egg diameters increased with increased fish length. Egg diameters increased with increased fish length.