Marine and Freshwater Research Marine and Freshwater Research Society
Advances in the aquatic sciences
RESEARCH ARTICLE

Temporal patterns in the size of the main commercial shark species of Western Australia

Matias Braccini

Western Australian Fisheries and Marine Research Laboratories, PO Box 20, North Beach, WA 6920, Australia. Email: matias.braccini@fish.wa.gov.au

Marine and Freshwater Research - http://dx.doi.org/10.1071/MF16117
Submitted: 7 April 2016  Accepted: 3 August 2016   Published online: 1 September 2016

Abstract

Declines in the mean size of harvested organisms may indicate overexploitation. In the present study, temporal patterns in the mean size of the four main commercial shark species of Western Australia were evaluated. Unlike commonly observed for other shark populations, there were no strong temporal patterns in the mean size of gummy, dusky and whiskery sharks, whereas the mean size of sandbar sharks showed a gradual increase since 1993. These observations add further evidence that sharks can be fished sustainably when adequate monitoring, assessment and management actions are implemented.

Additional keywords: gill nets, overexploitation, sustainable fishery.


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