Before someone gets seriously hurt simply for doing their job, let's take a deep breath and admit the debate over the use of 1080 in New Zealand's bush has got out hand – and needs something like a Commission of Inquiry to calm everything down.

See, when the Department of Conservation office in Palmerston North gets "closed" – people have had to knock, and be known, to enter – because idiots have been tampering with staff vehicles and the like, it's time to find a valve to let the steam out.

And boy, is there a lot of it needs venting!

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Start any discussion about 1080 on social media and you will quickly have otherwise-upright folk of the anti- persuasion spreading rumours and uttering dire warnings against the "mass poisoners".

Even asking for factual evidence – as I did in researching this piece – leads to people declaiming about how "captured" one is presumed to be.

That they fail to provide any hard evidence to back up such a dogmatic stance rather undermines their cause. Note: the Graf brothers' "evidence" is not credible.

And that's the problem: despite all the rage sparked by anecdotal tales of some sort of Apocalypse Now happening in the bush because of 1080, there is very little established fact to back that up; whereas quite a substantive body of evidence indicates that 1080 works – without significant side-effects.

Trouble is, many facets are easily misinterpreted.

First, no disputing there are some "by-catch" bird and animal deaths resulting from 1080 drops, including goats and pigs – which are not supposed to eat the pellets, but do. However the known (even including anecdotal) number of such deaths is small, and in the case of native birds, minuscule.

Some hunters point to large swathes of bush being empty of birdlife as evidence of the harmful effects of 1080. But when an area (such as the Kawekas) has had no such drops, that claim collapses.

Truth is, most of our existing hill country bush is primarily beech forest, which lacks sufficient food to sustain birds – so with or without poison, you won't find them there.

They'll be in the lowland forests instead.

Where there were birds and they have disappeared, it's usually either because deer have invaded the area and eaten all the bird food, or there's been an (irregular) "masting" event – the trees have suddenly produced a wealth of seeds.

That attracts the real villains: mice who eat the seeds, which brings rats to eat the mice, which brings stoats to eat the rats; and in winter when this food runs out, they eat the birds.

When such an event happens, DoC's "battle of the birds" 1080 programme is the only option to prevent birdlife being slaughtered.

People who have lost dogs to 1080 may be right to be upset but are wrong to assume other animals will also die; dogs happen to be particularly susceptible to sodium fluoroacetate - the poison in 1080 baits.

Fortunately, possums and rats are also very susceptible. Which is why it's used.
As for people becoming ill from 1080 in a carcass or water, toxicology says that's improbable - because the amount you would need to ingest is huge. Besides, a pig so badly poisoned would already have died.

Those "impact" issues aside, I am against the use of poisons in general, and indiscriminate use in particular. So if there were a realistic alternative, I'd oppose 1080 unreservedly.

But as things stand, it's the only effective tool we have for sustaining our native birds, which unlike elsewhere have no natural defence against predators. The stark "no-drop" choice is their extinction.