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The Bronze Whaler is distributed widely, but patchily, throughout the world's warm temperate (and some tropical) oceans [Last and Stevens 2009]. In Australia, the species occurs around the southern coastline, from approximately Coffs Harbour in NSW to Geraldton in WA. Available evidence supports a single biological stock, which is classified as undefined, in Australian waters.

Photo Credit: Clinton Duffy, FishBase

South Australia approximates the centre of the Australian distribution of the Bronze Whaler (Carcharhinus brachyurus) [Last and Stevens 2009]. The Bronze Whaler is highly mobile, seasonally migratory and has a cosmopolitan warm-temperate distribution [Last and Stevens 2009]. Adult and juvenile sharks inhabit coastal and shelf waters of the west, south and east coasts of Australia between approximately Coffs Harbour in New South Wales and Geraldton in Western Australia [Last and Stevens 2009]. Information on the genetic structure of the population suggests that the Indian Ocean is a geographical barrier to gene flow between Australia and South Africa [Benavides et al. 2011]. Within Australian waters, genetic analyses indicate there is a well-mixed stock ranging between western, southern and eastern Australia. Analyses using single-nucleotide polymorphisms (SNPs) provided some support for a potential separation of Western Australia from the rest of Australia and New Zealand (based on neutral loci only), however, this was only based on two (Augusta, Western Australia) of 103 samples [Junge et al. 2019] and should be treated with caution. Movement processes underlying the preliminary stock structure hypothesis (panmixia) have been studied using telemetry techniques at a range of spatial and temporal scales. The South Australian gulfs form important seasonal foraging habitats in spring-summer [Rogers et al. 2012], with juveniles and adults [Rogers et al. 2013; Drew et al. 2019] moving out of both Spencer Gulf [Rogers and Drew 2018] and Gulf St Vincent during autumn [Drew et al. 2017]. Long-distance migrations were documented across Southern Australia with Bronze Whalers forming a single biological stock spanning from Western Australia to New South Wales [Rogers et al. 2013; Huveneers et al. 2021].

Based on available evidence including seasonal catch and tagging patterns, genetic population structure, and movement patterns determined from conventional and electronic telemetry, Bronze Whaler is assessed here as a single biological stock spanning South Australia, Victoria, New South Wales, southern Queensland at the species range limits, and Western Australia. Additionally, Bronze Whaler inhabits Commonwealth waters adjacent to these jurisdictions).

Here, assessment of stock status is presented at the biological stock level—Southern Australia.

Bronze Whaler biology [Drew et al. 2017]

Distribution of reported commercial catch of Bronze Whaler

Commonwealth – Catch. Catch provided for the Commonwealth align with the 2021–22 financial year. 

Commonwealth – Recreational. The Australian Government does not manage recreational fishing in Commonwealth waters. Recreational fishing in Commonwealth waters is managed by the state or territory immediately adjacent to those waters, under its management regulations.

Commonwealth – Indigenous. The Australian Government does not manage non-commercial Indigenous fishing in Commonwealth waters, with the exception of the Torres Strait. In general, non-commercial Indigenous fishing in Commonwealth waters is managed by the state or territory immediately adjacent to those waters.

Western Australia – Recreational (Management Methods). A recreational fishing from boat licence is required for recreational fishing from a powered vessel in Western Australia.

Queensland – Indigenous (Management Methods). For more information see: https://www.daf.qld.gov.au/business-priorities/fisheries/traditional-fishing

New South Wales – Indigenous (Management Methods). https://www.dpi.nsw.gov.au/fishing/aboriginal-fishing

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