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Tropical marine ornamentals comprise an increasingly important fishery worldwide. Although the potential for overexploitation of marine ornamentals is great, few studies have addressed the population-level impacts of ornamental exploitation and few ornamental fisheries are managed. Analysis of catch records obtained from collectors over a four-month period in the vicinity of Cebu, Philippines, showed that anemonefish and anemones comprised close to 60% of the total catch. Underwater visual census surveys revealed that both anemone and anemonefish densities were significantly lower in exploited areas than in protected areas. The low density of anemones on exploited reefs accounted for over 80% of the reduced density of anemonefish at those sites. There were similar numbers of anemonefish per unit area of anemone in protected and exploited sites; however, biomass of anemonefish per unit area of anemone was lower in exploited areas. Reduction of anemone removals is recommended to support the sustainable harvest of anemonefish from this region.

The larval settlement rate of the Indo-Pacific reef coral,Pocillopora damicornis, on bare glass was compared with the rate on glass covered with measured amounts and area of fine sediment. Larval settlement in all sediment treatments was significantly less than on bare glass. Sediment cover of 95% completely prevented settlement. There was no increase in settlement when sediment cover was reduced from 90% to 50% of the glass surface area. If planulae of many coral species behave in a similar fashion in nature, sedimentation at a level that only partially covers the substrate and that is not directly harmful to adult colonies could significantly reduce larval recruitment by inhibiting settlement.