Introduction It is well known that demersal and reef-associated sh require hard bottom as habitat for population establishment and growth-for sh to settle as larvae, grow into adulthood, and reproduce (Orth et al. 1984, Choat and Bellwood 1991). These life stages are further enhanced when the hard bottom has a complex three-dimensional structure, affording habitat for feeding, breeding, and refuge from predators and competitors (Doherty 1991, Syms and Jones 2000). Scleractinian corals on hardbottom habitat enhance three-dimensional structure (Nagelkerken 1977, Luckhurst and Luckhurst 1978, Thresher 1983, Bell and Galzin 1984, Roberts and Ormond 1987, Jones 1991), which is one of the reasons why coral reefs possess such high reef sh diversity and abundance.