Environment Minister David Speirs, whose high-profile ban on single-use plastics came into force today, is “pondering” nominating for preselection in the marginal southern suburbs seat, whose boundaries traverse his current state seat of Black, according to party sources.

While the move – following former state Upper House president Andrew McLachlan’s senate shift last year – remains unlikely, it’s understood Speirs is taking soundings from confidants about the prospect.

Approached for comment, he told InDaily: “I’m genuinely flattered to have had so many people approach me about this opportunity, but at the moment I’m doing a job that I love – delivering for our environment as South Australia’s environment minister and driving forward a nation-leading agenda: driving a progressive climate action agenda, banning single use plastics and delivering a historic increase in national park spending.”

Flint shocked colleagues late on Friday when she confirmed she was leaving parliament at the next federal election, which many anticipate will fall later this year.

While she is yet to publicly address the reasons for her decision, it has been speculated that Canberra’s “toxic” culture had contributed to her resignation, with the events of the past fortnight, during which successive rape allegations have dominated the federal agenda, reportedly weighing heavily on her.

She had also been targeted by GetUp! at the previous poll and seen her office vandalised with offensive slogans on several occasions.

Prime Minister Scott Morrison said in a statement on Friday night: “The public attention from being a parliamentarian does sometimes attract unacceptable behaviour, and I have admired Nicolle’s efforts to stand against the bullying and nastiness of particular groups and individuals.”

Morrison said the Liberal Party would work to “ensure we put forward a Liberal candidate who brings the same high-calibre qualities to the people of Boothby as [Flint] has”.

That’s set to drag the proverbial Melbourne Cup field of nominees into the preselection contest, with a range of political staffers mentioned as potential contenders.

These include Right-winger Zane Basic from Flint’s own office, as well as Marion Themeliotis and Matt Shilling, councillors with Onkaparinga and Marion who also work for McLachlan and state MP Steve Murray respectively.

Another Flint staffer, Adelaide City councillor Alexander Hyde, today ruled himself out of contention.

Former federal Adelaide candidate Shaun Osborne told InDaily it was “too early to tell” whether he would nominate for the vacancy, saying: “I’ve got to consider my options and make a decision.”

Others mentioned by party insiders include moderates Cara Miller and Rachel Swift – who was last month relegated to the unwinnable fourth spot on the Liberal ticket – local Leah Blyth and former Port Adelaide federal candidate Emma Godfrey.

Multiple party insiders also speculated that SA’s chief public health officer Nicola Spurrier could be sounded out about making a switch to politics, but she shot the suggestion down today, with an SA Health spokesperson telling InDaily she had “not been approached” and was “not thinking about it – it’s a no”.

If Speirs opts to run, it could have dramatic implications on North Tce, where Liberal sources say the Environment and Water Minister is “a bit on the outer” with the moderate-dominated cabinet.

While pushing a progressive environmental agenda, Speirs is considered by the Right faction as “socially conservative”.

He took on moderate heavyweight Vickie Chapman in recent days by leading the charge on significant amendments to her abortion Bill, which he also voted against.

The timing of the federal election could also leave his Black electorate vacant in the lead-up to the state election, with the Liberals already in minority government after the loss of Fraser Ellis and Sam Duluk to the crossbench.

The latter’s Waite electorate covers a significant part of Flint’s Boothby seat, with the Waite sub-branch – which remains overwhelmingly loyal to the incumbent – likely to wield significant influence in deciding Boothby’s next candidate.

Labor, meanwhile, is yet to open nominations for its own candidate, after 2019 hopeful Nadia Clancy came within 1.38 per cent of snaring the seat on the back of a 1.33 per cent swing.

Clancy, however, has since been preselected for the state seat of Elder, and told InDaily she had no intention of switching her focus back to federal parliament.

“No, my plans are still the same – I’m still going to be running for Elder,” she said.

She said she wished Flint “the best”.

“It’s disappointing – I feel sad that she isn’t able to continue in something that she clearly did want to do,” she said of her former opponent’s departure.