Résumé
Coral reef fish larvae can potentially use a range of stimuli to locate and orientate towards natal reefs. While a high proportion of juvenile clownfish Amphiprion percula settle on natal reefs, how they find their way home is unknown. In Kimbe Bay (Papua New Guinea), A. percula is most abundant on the shallow reef flats and in lagoons associated with isolated vegetated islands and is rare on reefs without islands. Here we used a series of pair-wise choice experiments to investigate the role of water-borne olfactory cues potentially used to find islands. Recently settled juvenile A. percula preferred: (1) Water collected near islands instead of offshore water; (2) Water taken from reefs with islands instead of water from reefs without islands; and (3) Natal lagoon water instead of water from another lagoon. In addition, (4) juveniles preferred water treated with rainforest leaves compared to untreated offshore water. We hypothesize that A. percula use a cocktail of olfactory stimuli to locate vegetated islands, which may explain the high levels of self-recruitment on island reefs. This previously unrecognised link between coral reefs and island vegetation argues for the integrated management of these pristine tropical habitats.