It is disappointing little progress appears to have been made catching the culprit who threatened to contaminate infant formula with 1080.
For all anyone knows, the threat might have just been foolish and misguided bravado and it could well have lacked real intent.
But that is not how the police and the country have treated the matter. Because the letter sent to Federated Farmers and Fonterra last November contained milk powder laced with traces of 1080, the menace had to be treated seriously.
The letter gave a deadline of the end of March for New Zealand to cease 1080 poisoning. That is now well past, and the work is about to resume with aerial drops around Wanaka set to begin after next Friday.
That is it the way it should be because this country cannot bow to blackmail and because 1080 is central to the fight for forest and native bird health and for Tb eradication.
Even most vociferous anti 1080 campaigners were horrified at the threat, it being a cross between economic vandalism and potential eco terrorism. It is hard to think of a worse crime than the possible random killing of babies.
The threat seems likely to be the work of an individual, because people talk and a group would have been much more likely to have been exposed by now. About six months have passed since the original letter was received.
Police have now said they continue to ''pursue a range of lines of inquiry'', whatever that means. Hopefully, that does not mean little progress has been made. Hopefully, even if an arrest is not yet possible, the police have a good idea who might be involved.
There is no doubting the passion of the anti 1080 lobby, however misguided its supporters might often be. Many are hunters, aware of how deadly the poison is to deer and to dogs. But it is those very lethal qualities that enables it to kill so many bush predators.
Fortunately, it is water soluble so has minimal direct impact on lakes, and rivers and fortunately it is relatively cheap. To try to keep on top of the pests, a few hundred thousand hectares are poisoned every year.
While it is important to keep an open mind about 1080, in the meantime New Zealand has no choice but to trust the vast majority of experts, including those in the Department of Conservation.
And not only has the Parliamentary Commissioner for the Environment, Jan Wright, strongly backed its use, but she has called for more areas to be covered. Under current technology and methods, widespread aerial application of 1080 is the only way to protect our native birds.
Sometimes, some birds are killed after 1080 application. And there are issues with kea that need more study. Overall, nevertheless, the benefits for birds far outweigh small temporary harm. It is the only way, at present, to keep our forests alive with bird sound.
This is not to say the search for other options should cease. Nor should precautions be loosened because 1080 is potentially toxic to humans as well as other mammals. At the same time, application has become more sophisticated and targeted.
The latest claim is that the little known and rare Roys Peak gecko will be put at risk by TBFree New Zealand's programme to aerial poison later this month because of ''exacerbated prey switching'' in stoats.
A TBFree manager, in contrast, says the 1080 drops will actually help protect gecko and their food supply.
Criticisms need to be examined and responded to. But at a certain point, members the public, who cannot independently verify conflicting scientific claims, have to often trust the official experts.
Poisoning with has to continue in the face of both last November's threat and other opposition. The environmental and economic stakes are too high not to.
