Tensions over the Department of Conservation's use of 1080 have flared, with protesters threatening staff and damaging property, the department says.
The Department of Conservation (DOC) has complained to police after it said staff were threatened and abused by anti-1080 campaigners on more than one occasion.
DOC's director general Lou Sanson said 20 instances of staff being verbally abused or property being damaged had been reported to police.
He said most of the threats had been made on social media, with people being personally named, including helicopter companies and contractors.
"We have had once incident of tyres being damaged on a private property."
Mr Sanson said the incidents were not limited to the Westcoast and Southland, and had occurred in the central North Island as well.
Mr Sanson said he had met with Police Commissioner Mike Bush yesterday, who had given DOC his full support.
"I am worried, that's why I've gone to the police" - Lou Sanson
He said DOC respected people's right to peacefully protest, but he said things had escalated this year.
"It's stepped up with personal attacks, personally naming people, personally attacking helicopter companies."
Mr Sanson said for large remote parts of New Zealand, 1080 was the only option for protecting primary industries and native wildlife.
"We just need New Zealanders to understand we're trying to do the best job for New Zealand."
"We're quite happy to debate the science, but until we get a magic breakthrough, if New Zealand's serious about cattle and bringing back its birds in wide parts of New Zealand that are inaccessible, this is really the only technique we have."