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.

Growth and reproductive biology of white-spotted rabbitfish (Siganus canaliculatus) on different seagrass habitats in Inner Ambon Bay, Indonesia

“…The fecundity of the female S. canaliculatus population in Inner Ambon Bay is relatively high, ranging from 198,400 to 783,750 eggs. Higher than the report of Suwarni et al (2019), who obtained 5,416-130,760 eggs (range of body length (8.5-24.5 cm TL), Tharwat (2004) 58,925-838,652 eggs (17.0-35.0 cm TL), but still below Al-Marzouqi et al (2011) which obtained 242,042-607,615 eggs (26.5-37.5 cm TL). According to Effendie (2002), fecundity variations in fish are related to age composition, feed availability, population density, temperature, and dissolved oxygen.…”

“…The sex ratio of S. canaliculatus between different seagrass habitats in Inner Ambon Bay is 1.1: 1.0-2.2: 1.0 (Table 3). Differences in the sex ratio of S. canaliculatus were also found by Wassef and Hady (1997) in the Arabian Gulf (1.4: 1.0-2.3: 1.0) and Suwarni et al (2019) in the waters of Jeneponto, South Sulawesi-Indonesia (1.7: 1.0-8.2: 1.0). The results of the Chi-square test showed that the sex ratio of S. canaliculatus in Inner Ambon Bay (Table 3) was significantly different in monospecific seagrass vegetation (P > 0.01), presumably due to the capture of fish of certain sex, which was more dominant.…”

“…It means that length and weight determine the value of fecundity. As found by Tharwat (2004), Al-Marzouqi et al (2011), Paraboles andCampos (2018), andSuwarni et al (2019). Paraboles and Campos (2018) recommend that the population of S. canaliculatus be allowed to grow at an optimal size to produce a large fecundity that has the potential to support the sustainability of its stock in the wild through a continuous recruitment process.…”

“…The size at first maturity of the male and female of S. canaliculatus tended to be different (13.2 cm-22.6 cm TL for males, and 13.9-25.7 cm for males) (Wassef and Hady 1997;Tharwat 2004;Al-Marzouqi et al 2011;Annand and Reddy 2017). S. canaliculatus has great reproductive potential with fecundity values ranging from 5400-2,500,000 eggs (Al-Ghais 1993;Paraboles and Campos 2018;Suwarni et al 2019;Latuconsina et al 2020 c ).…”

“…Research on the growth and reproductive biology of S. canaliculatus is common (Al-Marzouqi et al 2011;Annand and Reddy 2017;Suwarni et al 2019;Latuconsina et al 2020 c ;Suwarni et al 2020). Especially in the waters of Inner Ambon Bay, Manik (1998) and Latuconsina et al (2020 b ) have researched the population dynamics of S. canaliculatus.…”