"It is appalling [Mallard] can make that claim with no proof to discredit our cause. There is no way we would stoop to that level because we would become what we are trying to save."
Gurden said some of the birds, including two weka, a quail, and one of the kererū, were road-kill. The rest he said believed to have been killed by 1080, though he was not certain.
"I didn't watch them die, but the person who supplied them to me assured me they were from a 1080 drop zone on the West Coast from 2014.
"He is a scientist and had been keeping them in his freezer. He wanted to test them for 1080, but he couldn't afford it."
The group had not tried to mislead the public into thinking the birds had been poisoned by 1080, he said.
"It was an act of theatre. It was designed to show what we as parents and children live with every day in these drop zones."
Gurden was "born and bred" in Greymouth, and had spent his life living and travelling the West Coast.
He had seen birds killed by 1080, his dog had died after being poisoned, and he and his family had become ill from drinking tainted water, Gurden said.
"We see this death and torture every day."
Environment Minister David Parker told Newshub the dead birds would be tested to determine whether they had been killed by 1080, as the protesters alleged.
A police spokesperson said a complaint had been made in relation to anti-1080 protesters leaving dead native birds on the steps of Parliament.
Acting director-general for the Department of Conservation Mervyn English said New Zealand had a predator crisis and 1080 was needed.
"There is significant science behind the safe use of 1080 and its effectiveness in reducing predators that kill our native wildlife in the wilderness.
"1080 is saving our birds, plants and insects. We have a choice between rats, stoats and possums or our unique native species. I choose protecting our taonga."
English said DoC staff were also approached by anti-1080 supporters.
"There have been eight incidents where staff have been physically confronted, abused and harassed.
"There have been seven incidents of abusive phone calls or emails. There have been countless incidents of social media threats and abuse.
"Threats and abuse are completely unacceptable and people attacking DoC staff can expect to see the cops on their doorsteps."
Forest & Bird chief conservation advisor Kevin Hackwell said he was disappointed, but not surprised.
"Sadly, we have seen the anti-1080 protesters go too far, time and time again.
"The science does not back their case whatsoever. They are having to resort to these sort of tactics to make a fuss, and that is really sad."
Hackwell said if the birds were killed intentionally someone, someone must be punished.
"The courts are becoming increasingly strong in recent years, where people have done damage to native wildlife. They've clearly defined the possibility of jail time.
"I just do hope the police will investigate, that the people who are responsible are dealt with properly. The use of children is appalling."
