Retired fisheries scientist Jim Penn exposes scary truth about shark numbers off WA’s coast

The State’s former chief fisheries scientist warns WA’s great white shark population has been dramatically underestimated for decades, and there could be up to 10,000 of the predators along our coastline.

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Amy Cavender
The Nightly
Jim Penn, a retired fisheries scientist with more than 40 years of experience in stock assessment in WA and overseas, is calling for an independent reassessment of the white shark population
Jim Penn, a retired fisheries scientist with more than 40 years of experience in stock assessment in WA and overseas, is calling for an independent reassessment of the white shark population Credit: Ross Swanborough

West Australia’s great white shark population has been dramatically underestimated for decades, contributing to flawed management of shark mitigation strategies and a rise in fatal attacks, according to the State’s former chief fisheries scientist.

Jim Penn, a retired fisheries scientist with more than 40 years of experience in stock assessment in WA and overseas, is calling for an independent reassessment of the white shark population — including its size and long-term trends — to ensure mitigation strategies are based on accurate data.

Since white sharks were given full Federal protection in 1997, Dr Penn believes the population has increased, but he can only estimate by how much.

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A 2018 CSIRO assessment estimated 750 adult white sharks on Australia’s east coast, or about 5460 including juveniles. The southern-west stock had 1500 adults and, assuming a similar adult-to-juvenile ratio, could number about 10,000.

Following three fatal shark attacks in WA this year, and the possible 10,000 great white sharks lurking off the coast, would you support a cull? Vote below

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