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Sandbar Shark occurs primarily off both the east and west coasts of Australia. The eastern Australian stock is sustainable and the Western Australian stock is recovering.

Sandbar Shark (Carcharhinus plumbeus) occurs primarily off both the east and west coasts of Australia, from approximately latitude 17–32°S off the east coast, and latitude 13–36°S off the west coast [McAuley et al. 2007, Last and Stevens 2009]. The species is also encountered off the northern Australian coast, although in much lower numbers. In addition to genetic analysis that suggests limited gene flow between eastern and western Sandbar Shark stocks [Portnoy et al. 2010], there are limited recorded catches in the Gulf of Carpentaria and southern Australia. Thus, the species is considered to be represented by separate Eastern and Western biological stocks in Australian waters.

Here, assessment of stock status is presented at the biological stock level—Western Australia and Eastern Australia.

Eastern Australia

In New South Wales, whaler sharks (Carcharhinus spp.), including Sandbar Shark, have historically not been adequately identified and reported at a species level in commercial catch data. However, observer data indicate that Sandbar Shark represents the largest single-species component of catches in the Ocean Trap and Line Fishery (New South Wales), at 35 per cent of the overall shark catch between 2008 and 2009 [Macbeth et al. 2009]. Since the introduction of new logbooks in 2009, fishers are required to report all landed sharks to species level with improved reliability of species identification following development of a species identification guide and at-sea education via an observer program [Macbeth et al. 2018]. Since new management arrangements  were introduced in 2013–14, catch has not exceeded 3.8 tonnes (t) per annum, with 3.64 t reported for the fiscal year 2018–19. Insufficient information is available to undertake a quantitative stock assessment of any whaler shark species in NSW [Rowling et al. 2010]. Therefore, a weight-of-evidence approach combining catch data and analysis of Effective Population Size has been used to determine stock status. In Queensland, Sandbar Shark are caught in negligible quantities (<1 t per year combined since 2011) across the net and line fishery components of the East Coast Inshore Fin Fish Fishery. A peak in combined harvest occurred in 2010 (1.6 t) with harvests not exceeding 0.6 t since then [QFISH 2020], contributing little to the overall eastern Australian harvest of the species. New software known as NeOGen [Blower et al 2019] has been developed which enabled calculation of the total population of Sandbar Sharks on the eastern Australian coastline to be approximately 105 000 individuals based on 476 genetic samples [Blower 2020].  Simulations at current fishing levels indicate observed fishery harvest volumes to be sustainable [Blower 2020]. The above evidence indicates that the biomass of this stock is unlikely to be depleted and that recruitment is unlikely to be impaired. The above evidence also indicates that the current level of fishing mortality is unlikely to cause the stock to become recruitment impaired.

On the basis of the evidence provided above, the Eastern Australia biological stock is classified as a sustainable stock.

Sandbar Shark biology [Geraghty et al. 2013, McAuley et al. 2007, McAuley et al. 2006]

Distribution of reported commercial catch of Sandbar Shark

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

New South Wales commercial fisheries with less than seven active fishers are not presented due to the Privacy Act.

Recreational and Indigenous (catch) Given the offshore distribution of Sandbar Shark, near-shore catches are likely to be negligible.

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