Like all anemonefishes, Amphiprion percula forms symbiotic relationships with sea anemones. It uses its host as both shelter and protection from predators. Because of this close relationship, the distribution of suitable host anemone species dictates the habitat of Amphiprion percula. Associations involving Amphiprion percula and the sea anemone species Heteractis magnifica, Stichodactyla gigantean, and Stichodactyla mertensii are usually found in nature (Elliott and Mariscal, 1996). Both symbionts reside in shallow coastal waters of the tropics where depth rarely exceeds 12 meters and water temperature ranges from 25-28 degrees C. (Randall et al., 1997; Fautin and Allen, 1992). The distribution of sea anemones themselves is limited by the photosynthetic activity of golden-brown algae that occupy the anemones’ tentacles (Fautin and Allen, 1992). The fish and anemone pair generally occurs on coral reefs where the latter is anchored securely and the former can be seen swimming in and out of the protective tentacles of its host.

When several species of anemonefishes occur together in similar habitats, they tend to partition themselves according to microhabitats and available species of sea anemones. Amphiprion percula, for example will typically occupy Heteractis magnifica in nearshore zones while Amphiprion perideraion will occupy the same species in offshore zones. Intense competition for limited resources undoubtedly affects the territorial nature of these fishes. Niche differentiation is caused by distribution, abundance, and recruitment patterns of competing species (Elliott and Mariscal, 2001). (Elliott and Mariscal, 1996; Elliott and Mariscal, 2001; Fautin and Allen, 1992; Randall, Allen, and Steene, 1997)