CANBERRA, Australia — An American diver’s death in the jaws of a great white shark off Australia’s southwest coast has raised the specter of a rogue man-eater preying on a renowned aquatic playground, killing three men in two months.

But scientists say three sharks more likely are responsible.

Australia’s southwest corner has been better known for whale and dolphin-watching cruises, white sandy beaches, world-class surf breaks and the peppery shiraz of its Margaret River premium wineries than for fatal shark attacks.

“I’m desperately … praying this is not the beginning of a new trend … and we’re going to have these on a regular basis,” Western Australia Fisheries Minister Norman Moore said Sunday.

On Saturday American George Thomas Wainwright, 32, was attacked while diving solo off a boat near Rottnest Island, a few miles from Perth.

The Western Australia state government set tuna-baited hooks off the island Sunday, the first time authorities have used an emergency legal exemption from the state protection of great whites as an endangered species in the interests of protecting the public.

Western Australia Premier Colin Barnett also said his government would consider shark culls, responding to locals’ complaints that shark numbers are increasing off bustling beaches in one of Australia’s fastest growing population areas.

But Barry Bruce, a federal government marine biologist with extensive research experience in tracking the movements of tagged great whites via satellite and in examining their behavior, said it was unlikely that a single, lurking predator killed the three recent victims.

“What we’ve seen tragically is three cases of people by sheer bad luck being in the wrong place at the wrong time,” he said.