Shark expert to investigate cull

One of Australia's top shark experts will be appointed to scrutinise the scientific claims underpinning the Barnett Government's contentious shark drum-line program.

The environmental watchdog revealed it would appoint the scientist to peer review the policy, including claims of between 3400 and 5400 great white sharks between Victoria and WA.

The move by the Environmental Protection Authority comes after the Government last week referred its plans to the regulator to extend the trial carried out last summer.

Under the plans, baited drum lines will be set off Perth and South West beaches between November 15 and April 30 over the next three years to catch great white, tiger and bull sharks bigger than 3m.

Just 25 great whites are expected to be caught by the lines over the period, the Government says.

EPA chairman Paul Vogel said questions relating to the policy's effect on great white stocks would be crucial to whether it was deemed environmentally acceptable.

Dr Vogel said it was for these reasons in particular that the scientist, whose name he was not prepared to release, would be asked to put the policy under the microscope.

"It is really important with a project like this, which is likely to have contested science, that we as the EPA get a credible, authoritative expert in this field to advise us," Dr Vogel said.

Conservation Council of WA director Piers Verstegen said the appointment of an expert would be meaningless unless the EPA gave them proper scope to investigate the Government's policy.

"It sounds like it might be a way of finding someone who supports shark culling and thinks that they are a shark expert and providing additional support to the Government's policy," Mr Verstegen said.