Biological analysis of adult rabbitfish (Siganus guttatus bloch, 1787) in seagrass and coral reef ecosystems at laikang bay, takalar regency

Abstract

The rabbitfish (Siganus guttatus) is a fish which has a high economic value also became one of the most popular types of fish consumed by the Takalar people up to Makassar City. The high market demand makes the effort to catch fishermen become greater so that the pressure on this species also becomes greater. therefore this research is needed to provide information in the preparation of comprehensive and systematic management strategies by policy makers to maintain the sustainability and sustainability of Siganus guttatus resources in the waters. The scope of this research includes information on rabbitfish habitat, abundance, feeding habits, sex ratio, and gonad maturity level (GML), as well as to compare the distribution pattern, gut content and GML in seagrass and coral reef ecosystems. This research was carried out from March to June 2017 in Laikang Bay, Takalar Regency, South Sulawesi Province, Indonesia. Rabbitfish samples (N = 336) were collected, comprising 293 males and 43 females with the size ranges of 11.2 – 35.9 cm and 8.4 – 35.4 cm, respectively. GML ranged from I – V. The GML in coral reef ecosystem was generally higher than in seagrass. The GML and number of individuals from the coral reef ecosystem were: GML I (133 fish), GML II (84 fish), GML III (30 fish), GML IV (12 fish), GML V (8 fish); whereas from seagrass ecosystem, GML I (12 fish), GML II (11 fish), GML III (2 fish). Gut content analysis found 36 phytoplankton species; the taxa comprising the highest percentages were Thallassiothrix sp. (69.24%) in the coral reef ecosystem and Oscillatoria sp. (26.34 %) in seagrass.