• Friday Forum: Should we be killing sharks in WA?

Shark supporters were given more ammunition against Western Australia’s controversial catch-and-kill policy, after undersized sharks were hooked and released within hours of baited drumlines being set off Perth beaches.

Using large hooks that the state government said would not catch smaller sharks, Fisheries officers placed bait off five of Perth’s busiest beaches at Friday’s first light.

Hours later, a one metre tiger shark was caught off Cottesloe beach – where a mass rally against the policy is set to be held on Saturday.

Under the gaze of a floating media pack, but with no sign of protesters, three Fisheries officers brought the animal aboard to check its size and condition, and then released it.

Moments later, a larger tiger shark was wrangled by the Fisheries officers after being caught on the hooks, but then also released.

Swimmers at Cottesloe — Premier Colin Barnett’s electorate — were then warned by Surf Life Saving to exercise caution, as the 2.6m tiger shark had been released 1km from shore.

The footage of the thrashing sharks are set to inflame an already vitriolic debate, which has divided Perth and forced Mr Barnett to go on the defensive.

The attacks continued from as high up as Sir Richard Branson, who said the culling policy will backfire, driving away tourism rather than boosting it.

The billionaire entrepreneur made the comment on breakfast radio as Fisheries officers were readying to deploy the drumlines.

The WA government says a spike in often-fatal shark attacks has dented tourism and leisure-based businesses, with recreational diving operators reporting a greater than 90 per cent plunge in people learning to dive.

But Sir Richard, a major critic of China’s shark fin trade, says WA is getting a bad reputation internationally and tourists will be driven away.

“I’m sure one of the reasons he (Mr Barnett) did it was because he was thinking it would encourage tourism. It’s going to do quite the reverse, I think,” Sir Richard told Fairfax radio on Friday.

“You’re advertising a problem that doesn’t exist in a major way and you’re deterring people from wanting to come to Perth and your beautiful countryside around it.

“All you’re going to achieve, I think, is to worry people unnecessarily.”

And with WA facing the prospect of going back to the polls later this year after the senate voting bungle, the Greens said the shark policy could cost the Liberal party dearly.

“You have the premier of Western Australia in cahoots with the Abbott government now going out and trying to destroy great white sharks,” Federal Greens leader Christine Milne said.

“It is wrong to institute this cruel policy, which will have by-catch as well.

“(Federal environment minister) Greg Hunt and Tony Abbott do not care about Australia’s native plants and animals, and I support anyone taking legal action to prevent what Colin Barnett is doing.”

Up to 5000 people are tipped to attend Saturday’s rally at Cottesloe, while other rallies are planned around the state, the rest of Australia and New Zealand.