University of Tasmania
Browse
Bestleyetal2009_SBTdivingbehaviour.pdf (1.29 MB)

Plasticity in vertical behaviour of migrating juvenile southern bluefin tuna (Thunnus maccoyii) in relation to oceanography of the south Indian Ocean

Download (1.29 MB)
journal contribution
posted on 2023-05-16, 23:52 authored by Sophie BestleySophie Bestley, Gunn, JS, Mark HindellMark Hindell
Electronic tagging provides unprecedented information on the habitat use and behaviour of highly migratory marine predators, but few analyses have developed quantitative links between animal behaviour and their oceanographic context. In this paper we use archival tag data from juvenile southern bluefin tuna (Thunnus maccoyii, SBT) to (i) develop a novel approach characterising the oceanographic habitats used throughout an annual migration cycle on the basis of water column structure (i.e., temperature-at-depth data from tags), and (ii) model how the vertical behaviour of SBT altered in relation to habitat type and other factors. Using this approach, we identified eight habitat types occupied by juvenile SBT between the southern margin of the subtropical gyre and the northern edge of the Subantarctic Front in the south Indian Ocean. Although a high degree of variability was evident both within and between fish, mixed-effect models identified consistent behavioural responses to habitat, lunar phase, migration status and diel period. Our results indicate SBT do not act to maintain preferred depth or temperature ranges, but rather show highly plastic behaviours in response to changes in their environment. This plasticity is discussed in terms of the potential proximate causes (physiological, ecological) and with reference to the challenges posed for habitat-based standardisation of fishery data used in stock assessments. © 2009 Blackwell Publishing Ltd.

History

Publication title

Fisheries Oceanography

Volume

18

Issue

4

Pagination

237-254

ISSN

1054-6006

Department/School

School of Natural Sciences

Publisher

Wiley-Blackwell Publishing Ltd

Place of publication

United Kingdom

Repository Status

  • Restricted

Socio-economic Objectives

Wild caught tuna

Usage metrics

    University Of Tasmania

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC