Temporal patterns in the size of the main commercial shark species of Western Australia
Matias BracciniWestern 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 68(6) 1112-1117 https://doi.org/10.1071/MF16117
Submitted: 7 April 2016 Accepted: 3 August 2016 Published: 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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