Chemical protection of a fish (Abudefduf leucogaster bleeker) by a soft coral (Litophyton viridis May).

Around Laing Island (Bismarck Sea), juveniles of the fishAbudefduf leucogaster are associated with the alcyonarianLitophyton viridis which, on mechanical stimulation, can release a potent ichthyotoxin and appears to be accordingly disliked by large predators. The fish has no special immunity to high levels of toxin but is affected more slowly than others. This has been interpreted in terms of an original strategy wherebyA. leucogaster plays its long reaction time against the diffusion of the toxin, allowing the fish to remain around the soft coral and benefit from indirect chemical protection. Possible biological implications of the toxin release are discussed.