The attraction of presettlement reef fish to FADs with live and dead coral

Abstract

Pelagic experiments with presettlement fish are rare and little is known of fish behaviour in the pelagic environment. This study was conducted at One Tree Island, Great Barrie Reef. It was hypothesised that fishes would be attracted to Fish Attraction Devices (FADs) and that fishes using chemical cues to locate suitable coral habitat at settlement would be attracted to live coral (Acropora horrida). Abundance of fishes were compared among experimental treatments that included FADs with live coral, FADs with dead coral and open water controls. Reef and other fishes were attracted to FADs and some reef fish (Abudefduf coelestinus, Petroscirtes sp.) were found in greatest numbers on live coral. Abundance of fishes around FADs with live or dead coral was generally greatest after four hours (cf two hours). Fish attracted to FADs were postflexion and generally pelagic juveniles. Reef fish that were abundant on FADs were also found in association with live A. horrida on reefs. Pelagic taxa were not attracted to live coral more than dead coral. FADs are an effective method for experimentation on presettlement forms in the pelagic environment and olfactory cues may influence colonisation rates, but calm conditions are required.