Contrasting Tide Effect on the Reef Fish Community and Abundance: Study Case on Coral Reef Restoration Site along Pramuka Island

Tides play an important role and host a diverse range of reef fish species. Some coral species and their associated fish have adapted to tidal conditions. It also creates currents that can affect the movement and distribution of reef fish. Kepulauan Seribu is one of the small tropical islands with many coral reefs. In this study, the community and abundance of reef fishes were examined at two different types of tides: high and low tides. Observations were made at a coral reef restoration site on Pramuka Island, the Thousand Islands.Tidal data were obtained from the Geospatial Information Agency (BIG) single daily tidal type (daily ebb tide) for the Pramuka Island. Reef fish abundance was found to be significantly different between high and low tides (ANOVA, F=14.84, P=0.003). With a range between 25 - 272 individual fish at high tide compared to 108 - 294 individual fish at low tide, it was found that fish were more abundant at low tide. The most species were found at low tide with a total of 65 species, while only 53 species were found at high tide. A total of 14 species were found exclusively at high tide, and 24 species were found exclusively at low tide. SIMPER analysis confirmed that 21 reef fish species contributed highly to the 75.82 differences in reef fish communities between low and high tides, with the five most contributing species being Pomacentrus alexandreae, Caesio teres, Neopomacentrus cyanomos, Cheilodipterus quinquelineatus, and Caesio cuning. Our findings generally indicate that, in terms of abundance and species richness, there are more fishes at low tide at the restoration site. This suggests that due to the diversity and abundance of species found under these conditions, tides should be considered when monitoring reef fishes.