KEY POINTS:
The Environmental Risk Management Authority has reviewed the use of 1080 and last year concluded that the benefits outweighed the risks.
The Government is refusing to back down on use of 1080 as opposition to the poison reaches unprecedented levels and workers spreading it fear for their safety.
Animal control officers working on the South Island's West Coast - the key battleground in the debate - are even bringing in security guards for their safety after alleged threats and intimidation by 1080 opponents.
Police are investigating the deliberate poisoning of one officer's dog with 1080 that led to it having to be put down. They are also seeking those responsible for sending mail containing 1080 pellets to politicians and Government agencies in Wellington, Nelson and the West Coast.
Opponents have long argued the poison drops kill not only the targeted pests, such as possums, but also other wildlife. Their claims have been borne out in one recent aerial drop that led to the death of seven kea, and another which resulted in the death of at least 10 deer on a West Coast farm last week.
In Parliament, the Government has been under fire, but ministers overseeing agencies using the 1080 are refusing to be swayed.
"We know that there is some impact on other species," said Conservation Minister Steve Chadwick.
"[But] the major threat to most New Zealand wildlife is from predators, such as possums, stoats and rats.
"Aerial 1080 is still our best tool for controlling these pests in our rugged back country. Without 1080 we could not eliminate bovine tuberculosis or protect our forests and wildlife."
Agriculture Minister Jim Anderton maintains 1080 is a "relatively safe poison" when compared with the likes of cyanide, previously used to control possums.
"Some people have significant philosophical opposition to 1080, and there is a lot of misinformation and emotion around the issue."
In Karamea, near the top of the West Coast, tourism-business owners have threatened to shut their doors because of a 1080 aerial drop, and are now exploring legal action.
Spokesman Paul Murray said there was now a groundswell of opposition against the "indiscriminate" 1080 aerial drops.
Although his group - Karameans Advocating Kahurangi Action - could not condone illegal acts, "I can understand the level of frustration people have".
The Animal Health Board, New Zealand's pest management agency, is concerned at how far protesters are willing to go, and has stepped up security around the poison and aircraft used for drops.
"The feedback is that a lot of people that perhaps don't like 1080 are even more disgusted by some of the tactics such as poisoning dogs," said chief executive William McCook.
1080: WHAT IS IT?
Sodium monofluoroacetate, commonly known as 1080, is a fine white powder and is a lethal poison to many species. The active ingredient, fluoroacetate, is identical to a substance that occurs naturally in many poisonous plants.
WHY USE IT?
The Department of Conservation says it is the best available poison to kill pests such as possums, which are destroying native bush and spreading tuberculosis to livestock. If unchecked TB could cost farming industries billions.
HOW DOES IT WORK?
If enough is ingested, the poison disrupts the process of breaking down food to provide energy for cells to function. Once the animal has run out of energy, it dies from heart or respiratory failure.
