I would like to thank Mr Hideyuki Tanaka for giving me the opportunity to carry out this study. I am indebted to Jean-Michel Guerin and Felix Nguyen for the assistance they gave in Port Vila, and to Jean-Michel, Alsen Fred, Albert Carlot and Mike Riepen for some interesting and helpful discussions. Very helpful comments on an early version of this report were made by Drew Wright of Forum Fisheries Agency. I greatly appreciated the kind hospitality of Felix, Simon Diffey and especially Jean-Michel. Gilbert David and Esperance Cillaurren of ORSTOM also gave assistance with access to literature and laboratory facilities.
