It was one of about 40 across the country on Saturday against the use of the pest-control poison.
Protesters, some wearing chemical hazmat suits and carrying banners decrying the use of 1080, gathered outside John Wickliffe House in Princes St, near the Dunedin office of the Department of Conservation.
They drew strong support from passing motorists honking their horns, before observing 10 minutes of silence.
Waikouaiti retiree Don Kendall said he believed the use of 1080 (sodium fluoroacetate) was a precursor to a United Nations plan for human depopulation in rural areas.
"And there’s been so much misinformation out there, and the powers that be talk about the science of it."
"I’m afraid, without trying to sound like a conspiracy theorist, it’s convenient science.
"The agenda is really UN Agenda 21 ... basically it’s a depopulation of the rural areas."
Agenda 21 is a non-binding United Nations resolution focusing on sustainable development, but has become the subject of a right-wing conspiracy theory arguing it is a totalitarian environmentalist plot.
Hunters were strongly represented at the protest.
Among them was Jay Callaghan, who said he was gravely concerned about the risk of his dogs being exposed to 1080.
"More to the point, it’s not just about hunting.
"It’s about ... the waterways, kiwis, bird life".
The Department of Conservation says dogs are particularly sensitive to 1080 and must be kept away from baits and carcasses.
In a 2011 investigation, Parliamentary Commissioner for the Environment Dr Jan Wright found 1080 was a safe and effective way of reducing the population of possums, rats and stoats.
Dr Wright also found 1080 breaks down naturally in the environment without leaving permanent residue in the earth, water, plants or animals. In a recent Science Media Centre Q&A, University of Otago AgResearch Chair in Reproduction and Genomics Prof Neil Gemmell said 1080 was the "best tool we currently have for large-scale pest control".
"The case of 1080 use is well established and it works — where it is used our native species are recovering, where it is not they die. It really is that simple."