Environmental advocates have questioned the practices of intensive salmon farms in the island state of Tasmania, accusing them of choking waterways with waste and fish faeces.

Greens Senator Sarah Hanson-Young said she was fed-up to the gills with a government that refused to enforce more stringent environmental standards.

"On the eve of an election, have you sold out your environmental credentials for a rotten, stinking extinction salmon," she said on a live feed of the proceedings, briefly pausing to heft the fish on to her desk.

A fellow Greens senator sitting behind her cried out: "It stinks".

She was swiftly ordered to remove the salmon -- sheathed in a plastic bag -- from the chamber.

Conservationists fear salmon farms are driving the extinction of the native Maugean skate, an endangered bottom-dwelling fish that looks something like a stingray.

But Prime Minister Anthony Albanese has vowed his support for the industry, which supports hundreds of jobs in Tasmania.

Australia has a history of questionable props being smuggled into the debating chamber.

Former conservative prime minister Scott Morrison once goaded renewable energy advocates by waving a lump of coal from the dispatch box.