Effects of herbivore grazing on juvenile coral growth in the Gulf of Mexico

This study demonstrates how herbivore grazing and substrate variations influence coral recruitment patterns at the Flower Garden Banks, Gulf of Mexico, for two brooding coral species, Agaricia spp. and Porites spp. Three herbivore treatments, two tile textures and two tile orientations were tested. Herbivore grazing significantly affected coral recruit growth for both species. These data suggested that Diadema antillarum may be destructively grazing since the recruits for both species were significantly smaller in the sea urchin treatment. Agaricia preferred rough textured tiles while Porites demonstrated no preference towards either tile texture. Preference for tile orientation differed between species, with Agaricia having larger coral recruits on vertical tiles and larger Porites were found on flat tiles. Our findings suggest that recruitment and growth of corals is species specific and should be considered as such when developing reef conservation strategies.