Shark numbers data renews WA cull debate

Scientists say there are about twice as many adult white sharks in southern-western Australasia compared to the east, reigniting the debate on culling, but Western Australia's environment minister is refusing to take the bait.

CSIRO scientists have estimated adult shark numbers using DNA from juveniles, with 750 adult white sharks in eastern Australasia and about 1460 in southern-western Australasia.

The research also found the total number of white sharks in the eastern population is 5460, but could not calculate the southern-western population.

Lead author Richard Hillary said adult survival was more than 90 per cent and adult populations were estimated to be stable since white sharks became protected in the 1990s.

"We can repeat the exercise over time and build a total population trend to see whether the numbers are going up or down," he said.

The results have renewed the heated shark debate in WA, where there have been 15 fatal attacks since 2000.

Federal Environment Minister Josh Frydenberg said the CSIRO study made a compelling case for WA to take stronger action, and referred to the shark control program in Queensland and mesh nets at more than 50 beaches in NSW.

The WA Labor government remains opposed to a cull in favour of its subsidy scheme for personal shark deterrents, and wants federal funding for research.

"Sadly, the federal environment minister seems to continue to want to play politics with this issue rather than deal with the science," WA Environment Minister Dave Kelly said.

He says it is a myth that there is no shark problem on the east coast, adding they had the same number of fatal attacks in the past five years as the west coast.

"We haven't had a fatal shark attack on a patrolled beach in WA in living memory," he said.

"It's people who are at more remote surf breaks or dive locations that are most at risk, and that's pretty much the same situation on the east coast.

"We tried drumlines in WA and it was a complete and utter failure ... it didn't even catch a single white shark."

Humane Society International head of campaigns Nicola Beynon said a shark cull would be irresponsible and called for non-lethal strategies.

"The aim of listing threatened species is not to restore numbers so that one day outdated and ineffective culling techniques and trophy fishing can be reinstated," she said.

But WA Opposition spokeswoman Libby Mettam said Mr Kelly was ignoring the fact that the CSIRO data did not include juvenile sharks under four metres.

"Smart drum lines - which are not operated to kill sharks but to manage and track them - clever buoys, netting and population management - which may include reopening shark fisheries - should all be options on the table," she said.

Back To Top