Tom Hall, a medical doctor who specialised in anaesthesia, said he was prepared to fight in Bass on the basis of balancing the environment with an economic setting which gave constituents "a fair go".

"I believe that the economy should work for all of us, but it doesn’t – it works for those of us who were born rich and those of us who are donors or mates with those who are in power," he said.

"And I see it at work every day. 

"Launceston is getting sicker but it’s not the doctors or lawyers or accountants that I spend most of my time treating. 

"It’s people with low-skilled employment, insecure employment, insecure and poor-quality housing, and people who have lost the faith that their children might have the opportunity to live a better life than they themselves have lived."

Dr Hall will be up against incumbent member Ross Hart, from Labor, and Liberal candidate Bridget Archer.

There was a 10.8 per cent swing towards the Liberals in 2013 which saw Andrew Nikolic elected, but in 2016, there was a 10.4 per cent swing against him which saw Mr Hart elected.

Biologist Gary Whisson will contest the seat of Lyons.

The 65-year-old worked for 30 years with the Western Australian Environmental Protection Authority before he moved to Orford in 2010.

He said during his career, he established the country's first conservation covenant scheme.

Mr Whisson said he was compelled to run in this year's election due to action needed on climate change and protection of coastal and marine environments.

He listed strong environmental protection laws and science-based management of the state's World Heritage Areas and reserves as key priorities. 

Mr Whisson will contest the seat held by Labor's Brian Mitchell since 2016.

Mr Mitchell claimed the marginal seat with a swing in his favour of 3.6 per cent.

He trailed then-incumbent Liberal Eric Hutchinson in first-preference votes but was helped across the line after the cut-up of Greens preferences. 

The Liberals have endorsed Jessica Whelan to run for Lyons this year.