WA Libs pledge two sharks nets per year

Two West Australian beaches will get enclosures to keep out sharks each year if the Liberal government is re-elected for a third term, Premier Colin Barnett says.

Mr Barnett officially launched a new enclosure at Quinn's Beach in Perth's north on Tuesday and said Rottnest and Rockingham - the electorate of his opponent Mark McGowan - were among several areas earmarked for nets in the future under a $2 million, four-year pledge.

"Rockingham has a large population, it's a big local government area. For exactly the same reasons we're planning to do Busselton, Geraldton and Mandurah, Rockingham is a logical place as is Rottnest Island ... one of the state's main tourist attractions," he told reporters.