Herbivorous fish are important to the coral reef ecosystem, bridging primary producers and upper trophic consumers. Their complementary functions (browsing, grazing, scraping and excavating) can limit algae, preventing it from shading corals from photosynthesis and opening up spaces for coral recruitment. However, the debate on top-down versus bottom-up control of algae has led to disagreement on herbivorous fish protective measures and enforcement within the Indonesia government. This research aimed to explore herbivore functions and link these to patterns in benthic community composition, so to explore the contribution of herbivorous fish. Surveys were carried out at the Kaledupa region, Wakatobi Marine National Park, Indonesia. DiverOperated Stereo-Video Counting was employed to film 3 x 50m transects (at each of 3 depth zones) for four sites. Algae percentage cover was found to be low at all sites, but grazers/detritivores group were found different and higher in the heavily fished site. Grazing functions seemed obvious. However, no significant correlation was found between herbivorous fish and algae. It is recommended that surveying be included on more sites. Notably, the functional length categories showed absence of fish £ 7.5 cm (fry stage) in 4 functional groups (except farmer), this was an alarming news of losing the species, hence, Wakatobi government is recommended to enforce protection on these length categories, by restricting the mesh size, prohibiting of certain type of gears and even having fishing closed seasons (Ahamadia et al., 2013; Comeros-Raynal et al., 2012).
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