Rapid and cost-effective assessment of connectivity among assemblages of Choerodon rubescens (Labridae), using laser ablation ICP-MS of sagittal otoliths

Authors

David V. Fairclough, Department of Fisheries, WAFollow
John S. Edmonds, Department of Fisheries, WA
Rod C J Lenanton, Department of Fisheries, WAFollow
Gary Jackson, Department of Fisheries, WAFollow
Ian S. Keay, Department of Fisheries, WAFollow
Brett M. Crisafulli, Department of Fisheries, WAFollow
Stephen J. Newman, Department of Fisheries, WAFollow

Document Type

Article

Publication Date

5-10-2011

Journal Title

Journal of Experimental Marine Biology and Ecology

ISSN

Print: 0022-0981 Electronic: 1879-1697

Keywords

Baldchin groper, Choerodon rubescens, Connectivity, Laser ablation, ICP-MS, otolith, trace element

Disciplines

Aquaculture and Fisheries | Marine Biology

Abstract

A rapid and cost-effective assessment was required to provide advice to management on the connectivity between juvenile and adult life cycle stages of Baldchin Groper Choerodon rubescens, a labrid endemic to the west coast of Australia, which has high social value, but relatively low commercial fishery importance. To minimise costs we used laser ablation ICP-MS to analyse levels of a small suite of elements (Ca, Mg, Mn, Cu, Zn, Sr, Rb, Ba and Pb) at the margin (adult phase) and core (juvenile phase) of the same otoliths of adult C. rubescens, collected at ten locations in five management zones. The elemental composition of both otolith margins and cores differed significantly among management zones and in some cases among locations within zones. Similarity of the pattern of among-zone elemental composition in otolith margins and cores indicated that, when cores are laid down, individuals have already recruited to the zones they will occupy as adults and there is no evidence of discrete juvenile nurseries. Thus, movement of juvenile or adult C. rubescens is likely to occur at relatively small spatial scales. Monitoring and management of adult stocks at the management zone level may be appropriate to sustain stocks broadly, but may not detect more localised depletion. Methods of elemental analyses are discussed and costs and benefits of this study vs an equivalent tagging study were compared.

Recommended Citation

Fairclough, D V, Edmonds, J S, Lenanton, R C, Jackson, G, Keay, I S, Crisafulli, B M, and Newman, S J. (2011), Rapid and cost-effective assessment of connectivity among assemblages of Choerodon rubescens (Labridae), using laser ablation ICP-MS of sagittal otoliths. Journal of Experimental Marine Biology and Ecology, 403 (1 to 2), 46-53.
https://library.dpird.wa.gov.au/fr_fja/99