Result
Fertilization and metamorphosis in control assays
The level of fertilization increased with sperm concentration to a maximum at 105 sperm mlÿ1 after 4 h (Fig. 1). This maximum was consistent with other researchers (Heyward et al., 1994; Reichelt-Brushett and Harrison, 1999) and was considered to be the optimum concentration for assay sensitivity. In control assay wells containing only coral gametes and filtered seawater, 97.70.4% (SE) eggs were fertilized after 4 h. No self-fertilization was observed in additional controls (no addition of sperm). In the absence of pollutants, 79.63.1% of A. millepora larvae underwent settlement and metamorphosis within 24 h of exposure to the crustose algal chips.