There are calls for a shark cull in western Australia after what one expert called an "unprecedented" number of deadly attacks, local media reported Sunday.

A 13-feet-long great white shark has been blamed for the latest fatality – the fourth in seven months – involving a scuba diver early on Saturday.

Peter Kurmann, a 33-year-old businessman and father of two young sons, was diving about a mile off Stratham Beach, 140 miles south of Perth, Western Australia (WA) according to a report in The Australian. It said the victim’s brother saw a ‘dark shape’ in the water at the time of the tragedy.

Scuba diver killed in Australia shark attack

In October, a 32-year-old man from Texas, George Wainwright, was killed by a shark off Rottnest Island along the same stretch of coast.

Ian Stubbs, mayor of the local Busselton area, has suggested a cull, saying the attacks are affecting tourism, the newspaper said.

“I think there should be a culling program because it's gone too crazy,” he was quoted as saying. “How many more of these tragic deaths can we continue to have? It's far too many."

Senior shark research scientist Rory McAuley told news site Perth Now that the current spate of attacks was "unprecedented”.

"I'm not aware of any series of fatal shark attacks, this number, in such a short period of time anywhere in the world,'' Mr McAuley was quoted as saying.

"So we really can't tell what's behind that. Last year a large proportion of the global shark fatalities occurred in Western Australia.

"In other years we haven't even registered on the shark attack files statistics. So last year was particularly bad. This year has already started very tragically."

However, The Australian said the WA state government has ruled out a cull because of the difficulties in identifying the sharks responsible.

The Sydney Morning Herald quoted WA state premier Colin Barnett as saying: "I am not advocating culling at all but I think there may be some scope, depending on the results of the research project, to allow increased fishing of shark which used to happen and has been restricted for various reasons."

It isn’t clear why the number of attacks has risen so sharply, but authorities say there is no evidence shark numbers are increasing. Tina Thorne from the WA government's Shark Response Unit, told broadcaster ABC: "What we'd like to do is put some solid science behind some of those theories and prove them or disprove them.” 

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AP

Adrian Vasquez, left, an 18-year-old Panamanian who worked in a seaside resort hotel, receives medical attention aboard an Ecuadorean navy ship on Sunday.

Updated at 6:01 a.m. ET: A teen has apparently survived 28 days adrift in the Pacific Ocean after going on a fishing trip with two friends, according to reports. Adrian Vasquez, who was rescued by the Ecuadorean navy on Sunday, said he stayed alive by drinking rainwater and eating raw fish, the BBC reported.

AP

Adrian Vasquez receives medical attention on Sunday.

The 18-year-old was found drifting alone near the Galapagos Islands on his friends' 10-foot fishing boat more than 600 miles from where they had set out.

He was first found by a commerical fishing vessel then handed over to Ecuador's coast guard. The trio had been missing since February 24.

The Associated Press reported the three were heading back to his home port of Rio Hato when the boat's motor failed.

Rainstorm
Vasquez told the Ecuadorean navy crew he likely owed his survival to a sudden rainstorm that replenished his water supply.

The young Panamanian recounted his story to Hugo Espinosa, captain of the navy vessel, after being treated for malnutrition and severe dehydration. He recalled they had caught a lot of fish, and had a big jug of water.

The AP quoted Espinosa as saying Vasquez had identifed his dead friends as Oropeces Betancourt, 24, and Fernano Osorio, 16.

Arnulfo Franco / AP

Rescued castaway Adrian Vasquez is surrounded by family members upon his arrival to Tocumen international airport in Panama City on Tuesday.

Panamanian navy boats began to search for the vessel but did not find it. Espinosa said the ice melted and the fish rotted, leaving the trio to live off what they could catch with their net.

"The spirits of the survivors began to wane with the passing of days," Espinosa told The Associated Press.

The report said Betancourt stopped eating and drinking after two weeks and died on March 10. Three days later, his body began to decompose and Vasquez threw it over the side.

AP

Adrian Vasquez, center, poses with Ecuadorean sailors onboard a navy ship on Monday.

Osorio died on March 15, also apparently of dehydration, sunburn and heat stroke. After three days, Vasquez pushed his other friend's body into the ocean, the AP said.

"When he was nearly dead, on March 19, it rained, and Vasquez was able to fill up with four gallons of water," said Espinosa. He spent the next five days eating raw fish before being spotted by commercial fishermen working on a skiff from a mother ship, the Duarte V.

'He was quiet'
Once aboard, Vasquez asked for a telephone so he could make two calls, the AP reported. The first was to his mother. The second was to the hotel manager to explain why he had missed so many days of work.

"He didn't know what was happening. He was quiet, looking lost," Espinosa said.

Vasquez was flown on Monday to Guayaquil on the Ecuadorean mainland before flying to Panama City on Tuesday where he was greeted by a crowd including family and friends.

The AP report said the teenager shed some tears as his relatives hugged him but he didn't talk to reporters.

The Associated Press and msnbc.com staff contributed to this report.

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