It is estimated there are about 40,000 feral deer across SA - an increase of 10,000 deer on last year's estimation - with about 24,000 in the South East region.
Limestone Coast Board chair Penny Schulz says it is a really big problem as there are deer in regions it had never before been expected they would live.
"We call it satellite population and we want to stop the spread of feral deer with our control options," she said.
"It is a really big complex problem and really expensive. Hundreds of thousands of dollars have already been spent and the federal government have also contributed to funding as well as $350,000 from the landscape authorities fund, which we hope to leverage to really have a go at this issue.
"We have a very assertive stance on the problem as deer are a biosecurity threat."
Ms Schulz said the deer carried disease and landholders were obliged to cull any feral deer on their farm or organise for it to be done.
"We also need to work with national parks and wildlife because they are in the parks but we need landholders to participate in aerial shooting," she said. "We are now trialing thermal shooting to eliminate deer we can not shoot with current conventional methods."
The Limestone Coast Landscape Board have culled 1380 feral deer this year with programs continuing, but need more landholders to come on board.
"It will need to be a collaborative effort from landholders, national parks and shooters to reduce feral deer numbers," Ms Schulz said.
Keilira landowner, sheep producer and former SE deer advisory committee member Lee Williams said feral deer was a complex problem in the landscape and people had ranging tolerances of deer on their land.
"We do not want deer, do not want the issues arising from feral deer on our property," she said.
"Participation in the helicopter program, or an organised ground shoot program, and a consistent approach across neighbouring properties including parks may be a way to halt the increase and spread of feral deer."
Ms Williams said she looked forward to a significant reduction in feral deer activity.
"We support and recommend the helicopter program, but it needs to be followed up by skilled ground shooters with a consistent all year round effort," she said.
But Padthaway farmer and deer shooter Joshua Haines said numbers had actually gone down in his experience.
"I do contract shooting for farmers and the eradication programs they have is having success," he said.
"Deer numbers have been decreasing over the years because more people have been doing it on foot and also engaging with the aerial shooting program."
Mr Haines said while the deer numbers were dwindling, the number of trespassers looking for trophy deer was out of hand.
"There is definitely heaps of poaching where people are going onto properties and shooting deer when they shouldn't be," he said. "It is a big issue down here."
Ms Schultz said if the SE region could get feral deer numbers down it might lose the reputation of being a great place to shoot deer and the illegal activity might stop.
A PIRSA spokesperson said registered and accredited professional shooters who could cull large numbers of the pest and were experienced in humane culls were best placed to conduct such operations, particularly on public lands where public safety risks also needed to be considered.
There are presently no plans for a feral deer bounty.
- Start the day with all the big news in agriculture. Sign up here to receive our daily Stock Journal newsletter.