Standard Talk (15 mins) Australian Society for Fish Biology Conference 2022

Sailfish science: building collaborations to delineate the global population structure of a migratory pelagic fish (#135)

Laura Smith 1 , Samuel M Williams 2 , Bruno Ferrette 3 , Julian Pepperell 4 , Ian R Tibbetts 1 , Christine L Dudgeon 5
  1. School of Biological Sciences, The University of Queensland, Brisbane, QLD, Australia
  2. Queensland Department of Agriculture and Fisheries, Brisbane, QLD, Australia
  3. Senckenberg Biodiversität und Klima Forschungszentrum, Frankfurt, Germany
  4. Pepperell Research & Consulting Pty Ltd, Sunshine Coast, QLD, Australia
  5. School of Biomedical Sciences, The University of Queensland, Brisbane, QLD, Australia

The sailfish (Istiophorus platypterus) is a highly mobile epipelagic billfish whose range extends across the world’s tropics and sub-tropics. Once thought to be different two species in the Indo-Pacific and Atlantic, molecular techniques revealed a single global species in the 1990s. Its patchy but widespread distribution in the open ocean means that it can be challenging to study. Our current understanding of the global population structure of sailfish is limited due to the low number of molecular markers used in previous studies and the difficulty in sampling across the extensive range of the sailfish. Collaboration with fisheries researchers and organisations has been a key element in building an extensive tissue sampling collection.

The high dispersal and movement ability of marine pelagic species, along with the lack of obvious barriers in the marine environment, can result in dilute genetic signal from population differentiation. Advances in next-generation sequencing technologies used a genome-wide approach to reveal population structuring for pelagic species at finer scales than previously detected using other methods. This research aims to determine structure and connectivity among sailfish populations across its circumtropical range in the Indian, Pacific, and Atlantic oceans using high-throughput genomic techniques. Novel genomic population structure will provide a baseline and inform future stock assessment and management, particularly where this information is lacking for the Indo-Pacific.