Shark nets can't protect swimmers in Australian waters

Shark nets used at most Australian beaches to protect swimmers have failed to reduce chances of being attacked, a new research revealed on Tuesday.

Analysis of data compiled over 50 years by Laurie Laurenson, from Victoria state's Deakin University, has found no correlation between the population of sharks and the number of attacks, Xinhua news agency reported.

Laurenson suggested that measures such as nets and drum lines that were designed to lower shark numbers near beaches were not making people any safer.

"I can show statistically that there is no relationship between the number of sharks out there and the number of attacks," Laurenson said.

"It's just simply not there... I'm surprised that it's not there but it's not there."

Barry Bruce, a shark expert at the Commonwealth Scientific and Industrial Research Organisation (CSIRO), said while shark nets have caught sharks, it does not mean they have prevented attacks.

A net, such as those used on Australian beaches, is a fishing device rather than a barrier, Bruce said.

"It's a couple of hundred metres long, there might be two at a beach which is many, many kilometres long. They are set at a depth offshore where they don't reach to the surface so they only come up six metres or so from the bottom in 10 metres of water. In some respects you have to be an unlucky shark to get caught," he said.

In a three-month period in 2014, drum lines in Western Australia (WA) caught 172 sharks, 163 of which were tiger sharks and none were great whites.

However, Laurenson's data reports that tiger sharks have not killed anyone in Western Australia for over 20 years.

There were 18 recorded shark attacks in Australia in 2015, according to the International Shark Attack File.