Reunion has a similar problem to WA, and officials there are at a loss.
"It is still illegal to surf, and the rules and regulations are simply in place to protect those officials in charge from getting into legal troubles, and not to protect ocean-users.
Reunion is the highest-risk location for a shark attack in the whole world, and little has really been done in shark mitigation processes.
There have been nets, there have been drumlines, and there have been extensive security watches – divers, boats, drones etc. – but all have been short-lived and experimental, while nothing is being done on a political level to stop the constant attacks.
A large chuck of coastline on the west coast of Reunion was declared a no-fishing zone back in 2007, and something went out of whack with the ecosystem in the process. There are many theories, including loss of natural food for sharks, and the sudden drop on shark catching, but either way, the bull sharks came to town."
https://www.tracksmag.com.au/news/the-sharks-of-reunion-485665