Stock structure of Grey Mackerel, Scomberomorus semifasciatus (Pisces: Scombridae) across northern Australia, based on otolith stable isotope chemistry

Authors

Stephen J. Newman, Department of Fisheries, Western AustraliaFollow
Ian W. Wright, Department of Fisheries, Western Australia
Ben M. Rome, Department of Fisheries, Western Australia
Michael C. Mackie, Department of Fisheries, Western Australia
Paul D. Lewis, Department of Fisheries, Western Australia
Rik C. Buckworth, Department of Regional Development, Primary Industries, Fisheries and Resources, Darwin, Northern Territory, Australia
Aaaron C. Ballagh, James Cook University, Queensland, Australia
Rod N. Garrett, Northern Fisheries Centre, Queensland Department of Primary Industries and Fisheries, Queensland, Australia
Jason Stapley, Northern Fisheries Centre, Queensland Department of Primary Industries and Fisheries, Queensland, Australia
Damien Broderick, University of Queensland, Australia
Jennifer R. Ovenden, University of Queensland, Australia
David J. Welch, James Cook University, Australia

Document Type

Article

Publication Date

6-22-2010

Journal Title

Environmental Biology of Fishes

ISSN

Print: 0378-1909 Electronic: 1573-5133

Keywords

Grey Mackerel, Scomberomorus semifasciatus, Otolith isotope chemistry, Stock structure

Disciplines

Aquaculture and Fisheries | Marine Biology | Natural Resources and Conservation | Natural Resources Management and Policy | Population Biology | Spatial Science | Sustainability

Abstract

The stable isotopes of δ¹⁸O and δ¹³C in sagittal otolith carbonates were used to determine the stock structure of Grey Mackerel, Scomberomorus semifasciatus. Otoliths were collected from Grey Mackerel at ten locations representing much of their distributional and fisheries range across northern Australia from 2005 to 2007. Across this broad range (∼ 6500 km), fish from four broad locations—Western Australia (S1), Northern Territory and Gulf of Carpentaria (S2, S3, S4, S5, S6, S7), Queensland east coast mid and north sites (S8, S9) and Queensland east coast south site (S10)—had stable isotope values that were significantly different indicating stock separation. Otolith stable isotopes differed more between locations than among years within a location, indicating temporal stability across years. The spatial separation of these populations indicates a complex stock structure across northern Australia. Stocks of S. semifasciatus appear to be associated with large coastal embayments. These results indicate that optimal fisheries management may require a review of the current spatial arrangements, particularly in relation to the evidence of shared stocks in the Gulf of Carpentaria. Furthermore, as the population of S. semifasciatus in Western Australia exhibited high spatial separation from those at all the other locations examined, further research activities should focus on investigating additional locations within Western Australia for an enhanced determination of stock delineation.

Recommended Citation

Newman, S.J., Wright, I.W., Rome, B.M. et al. Stock structure of Grey Mackerel, Scomberomorus semifasciatus (Pisces: Scombridae) across northern Australia, based on otolith stable isotope chemistry. Environ Biol Fish 89, 357–367 (2010). https://doi.org/10.1007/s10641-010-9668-z