Genomic population structure of great hammerhead sharks (Sphyrna mokarran) across the Indo-Pacific

Authors

Naomi L. Brunjes, University of the Sunshine Coast, School of Science, Technology and Engineering, Sippy Downs, Queensland, Australia.
Samuel M. Williams, University of the Sunshine Coast, School of Science, Technology and Engineering, Sippy Downs, Queensland, Australia.
Alexis L. Levengood, University of the Sunshine Coast, School of Science, Technology and Engineering, Sippy Downs, Queensland, Australia.
Matt K. Broadhurst, The University of Queensland, Australia
Vincent Raoult, Macquarie University, Ourimbah, New South Wales, Australia
Alastair V. Harry, Department of Primary Industries and Regional Development, Western AustraliaFollow
Matias Braccini, Department of Primary Industries and Regional Development, Western AustraliaFollow
Madeline E. Green, University of Tasmania, Hobart, Tasmania., Australia.
Julia L. Y. Spaet, University of Cambridge, Cambridge, UK.
Michael J. Travers, Department of Primary Industries and Regional Development, Western AustraliaFollow
Bonnie J. Holmes, University of the Sunshine Coast, School of Science, Technology and Engineering, Sippy Downs, Queensland, Australia.

Document Type

Article

Publication Date

4-10-2024

Journal Title

Marine & Freshwater Research

ISSN

Print: 1323-1650 Electronic: 1448-6059

Keywords

Australia, Gene flow, Management scale, Panmixia, Population genomics, Red Sea, Shark fisheries, Single nucleotide polymorphisms.

Disciplines

Aquaculture and Fisheries | Behavior and Ethology | Data Science | Marine Biology | Natural Resource Economics | Natural Resources and Conservation | Natural Resources Management and Policy | Population Biology | Survival Analysis | Sustainability

Abstract

Context

Currently, little information exists describing the population structure of great hammerhead sharks (Sphyrna mokarran) in Australian waters. Aims

This study used single nucleotide polymorphisms to investigate fine-scale population structure in S. mokarran across the Indo-Pacific. Methods

DNA was extracted from 235 individuals across six Australian locations and a Red Sea outgroup. Population parameters were calculated and visualised to test structuring across locations. Key results

No fine-scale population structuring was observed for S. mokarran across the Indo-Pacific. However, population structuring occurred for all Australian locations when compared to the Red Sea outgroup. Conclusions

Findings suggest a single stock is most likely for S. mokarran found in Australian waters. Results provide key information for understanding the broad range movements of S. mokarran and help to define the scale of management required to preserve genetic diversity in this species. The structuring between Australia and the Red Sea indicates limited gene flow and movement. Implications

Results indicate that large-scale movements of S. mokarran could be occurring to facilitate genetic mixing. Future research focusing on individual tagging to corroborate movements would be highly beneficial to determine how far (and often) individuals are dispersing, and to note where cross-jurisdictional management, including from neighbouring regions in the Indo-West Pacific–Oceania region, are most critical.

Recommended Citation

Brunjes Naomi L., Williams Samuel M., Levengood Alexis L., Broadhurst Matt K., Raoult Vincent, Harry Alastair V., Braccini Matias, Green Madeline E., Spaet Julia L. Y., Travers Michael J., Holmes Bonnie J. (2024) Genomic population structure of great hammerhead sharks (Sphyrna mokarran) across the Indo-Pacific. Marine and Freshwater Research 75, MF23236. https://doi.org/10.1071/MF23236