Oral Presentation Australian Society for Fish Biology Conference 2024

Sailfish science: building collaborations to delineate the global population structure of a migratory pelagic fish (111114)

Laura Smith 1 , Samuel Williams 2 , Bruno Lopes da Silva Ferrette 3 , Bonnie Holmes 4 , Nelly Isigi Kadagi 5 , Ching-Ping Lu 6 , Julian Pepperell 7 , Ian Tibbetts 1 , Nina Wambiji 8 , Sammy Wambua 9 , Christine Dudgeon 10 , Sofia Ortega Garcia 11
  1. School of the Environment, The University of Queensland, Brisbane, Queensland, Australia
  2. Queensland Department of Agriculture and Fisheries, Brisbane, QLD, Australia
  3. Senckenberg Biodiversität und Klima Forschungszentrum, Frankfurt, Germany
  4. University of the Sunshine Coast, Sunshine Coast, QLD, Australia
  5. World Wildlife Fund, Fort Lauderdale, USA
  6. National Taiwan Ocean University, Keelung
  7. Pepperell Research & Consulting Pty Ltd, Sunshine Coast, QLD, Australia
  8. Kenya Marine and Fisheries Research Institute, Kenya
  9. Pwani University, Kenya
  10. School of Biomedical Sciences, The University of Queensland, Brisbane, QLD, Australia
  11. Instituto Politécnico Nacional-Centro Interdisciplinario de Ciencias Marinas, Mexico

The sailfish (Istiophorus platypterus) is a highly mobile epipelagic billfish whose range extends across the world’s tropics and sub-tropics, which means it can be challenging to study. Once thought to be different two species in the Indo-Pacific and Atlantic, molecular analyses revealed a single global species in the 1990s. Our understanding of the global population structure of sailfish was limited due to the low number of molecular markers used in previous studies and the difficulty in adequate sampling across its range. Collaboration with fisheries researchers and the game fishing community allowed me to build an extensive tissue sample collection. My study used both neutral and adaptive loci from single nucleotide polymorphisms to explore contemporary population structure and connectivity in a global context for the first time in sailfish. Clustering analyses of neutral loci indicated three discrete populations in the Atlantic, eastern Pacific and Indo-West Pacific. However, analyses of a subset of putatively adaptive loci suggested there was a lack of connectivity across ocean basins in the Atlantic and Indian oceans. Novel genomic population structure provides a baseline for future studies, and informs stock assessments and cross-jurisdictional management for this migratory marine species.