Shark patrol flights will be making hourly sweeps along Adelaide's most popular beaches at peak swimming times this summer.
The annual fixed-wing plane coastline patrols for Sharks, from North Haven to Rapid Bay, will resume on Monday and continue between 11am and 8pm on weekdays throughout the summer.
The fixed-wing patrol planes would complement helicopter patrols that have already started on weekends and public holidays, the state government said in a statement.
During the week, beaches from North Haven to Sellicks will be swept hourly with extended flights as far as Rapid Bay several times a day.
On weekends and public holidays the patrols will extend as far as Victor Harbor and Goolwa, the statement says.
If the shark spotters see a shark close to swimmers or the shore, the plane will circle above the shark and sound a siren.
Swimmers should also swim at patrolled beaches and between the flags.
They should not swim alone, and should avoid swimming at dawn, dusk or night, in murky water or near people fishing or schools of fish.