A perspective on billfish biological research and recommendations for the future

Abstract

A review of papers published on billfish biological research since the 1988 Billfish Symposium highlights the important role these symposia play in disseminating billfish research results and also shows that progress since 1988 has been slow, especially when compared with tuna and other pelagic fishes. One reason for the disparity is that marlin have not yet been successfully held in captivity. Progress has been made in elucidating the trophic biology of billfish and these data are helping to build models of pelagic ecosystem dynamics. The deployment of several types of electronic tags has expedited advances in understanding the short-term movements and depth distribution of billfish, but long-term tracks remain elusive. In part, this may be because insufficient effort has been directed at developing methods for restraining marlin for tag attachment or implantation. Light-based geolocation techniques show great promise for elucidating billfish movements, but appropriate scientific rigour must be applied to the publication of these data. Several suggestions for advancing billfish research are presented.