New research has revealed around 5500 great white sharks are lurking in the waters off the East Coast.
For the first time, the CSIRO has been able to put a number on the size of the white shark population using world-first genetic analysis.
It estimates there are about 750 adults in waters east off Victoria's southern coast, up to central Queensland and across to New Zealand.
Taking juvenile sharks into account, researchers believe the total east coast population sits at 5460 - but could be as high as 12,800.
It's estimated another 1460 adult white sharks live off Australia's south-western coast, but a total calculation is yet to be made.
Until now, it was difficult to gather information about adult white sharks because they are hard to sample.
But breakthrough genetic and statistical methods means scientists can estimate shark numbers without having to catch or even see them, the CSIRO said in a statement on Friday.
"Now that we have a starting point, we can repeat the exercise over time and build a total population trend, to see whether the numbers are going up or down," the research paper's lead author, Richard Hillary, said.
"This is crucial to developing effective policy outcomes that balance the sometimes conflicting aims of conservation initiatives and human-shark interaction risk management."
