By - Wayne Linklater 09/05/2017

Predator Free 2050 is good politics but it is scientifically flawed.

It can’t be done. Predator-free 2050 was described as a “moon shot” but, actually, its an Andromeda Galaxy shot – unattainable. New Zealand’s, and the world’s, leading experts in animal eradication have already concluded that it is not possible to eradicate introduced mammalian predators from New Zealand. That consensus of expert opinion has been ignored.

PF2050 and the Department of Conservation (DOC) guiding it are under resourced. Its estimated cost is $32 billion but just a thousandth of that number has been set aside ($26 million).

The success of PF 2050 rests entirely on complicated solutions that are largely unknown, undeveloped and untested, like the genetic manipulation of wildlife. Those solutions have enormous technical and biological uncertainties to their use. The chances of actually being able to apply one of those solutions is next to zero.

Even if they could be made to work in the laboratory, the genetic manipulations of wildlife being proposed, like gene drive and Trojan females, will not eradicate predators because they attempt to work against biological evolution. The predator populations are genetically variable and they will mutate, there will be survivors, and they will repopulate. The first examples of gene drive failing because of genetic resistance has already been published.

On top of the uncertainties about the development and efficacy of new technologies, there are also large risks and barriers to scaling up existing technologies or releasing new ones. For example, while aerial broadcasting 1080 is understood to be necessary for the moment, it is also understood to pose a risk in our export markets because consumers are sensitive to inhumane practices and environmental toxins. The increase in 1080 broadcasting that PF2050 will require poses an ongoing political and economic risk.

Another example: the New Zealand public and international consumers of our produce are already wary of genetically modified organisms. Even the scientists at the forefront of developing gene-drive techniques are warning about their potential social and ecological risks. It is highly likely that a significant number of the public are going to find the release of genetically engineered organism into their backyards and schools unacceptable. These types of uncertainties and risks are greater than the technological and biological ones.

Ordinarily, no government, NGO, corporate or business would pose a goal that is not within it capacity to achieve. They would especially not pose such a high-risk strategy and then under-resource it. And for conservation the prospect of failure carries with it the potential to sacrifice public support for its broader goals.

Consider also that PF2050 is much less useful to biodiversity than we are led to believe. It is a single issue-single solution approach to biodiversity loss when it is, of course, more complicated. Predator eradication will improve the prospects for the few of our endemic and charismatic biodiversity (e.g., birds and reptiles) but not address the decline in the vast majority of New Zealand’s biodiversity that continues to be impacted by poor environmental standards and enforcement and ongoing habitat loss and pollution across most of the country. Moreover, ecological science has taught us that removing species will create new, and there will be additional, threats – competitors, other predators, parasites and diseases. Thus, PF2050 is not the best way to protect New Zealand’s environment and biodiversity over its greatest extent. PF 2050 is a political distraction from solving the greater environmental problems that we face as a country.

Given the above points, it becomes clear that PF2050 is a “green-wash” by the current government while it has worked to erode environmental and biodiversity protections everywhere else.

Fortunately, there is a better alternative to Predator Free 2050 that is based on better science and policy developed over the last 50 years. I describe that in my next post.


Featured image: Brisbane City Council

0 Responses to “Predator Free 2050 is scientifically flawed”

  • We are in real danger of letting naysayer semantics rob this vision of its tremendous value. In fact, the paper Linklater cites simply says what we all know perfectly well: we cannot eradicate these species (with the possible exception of possums) with any combination of tools we now possess. That’s why PF 2050 is a vision, but one that quite justifiably anticipates enormous advances in gene editing capability. It will easily fulfil one of its first ambitions – to inspire more research and investment in pest control. It was probably inevitable that a few contrarians would seize the opportunity to showboat, but we must remember that the rest of the scientific community has already set to work on this.

    • Dear Dave – thank you for your comment.

      Conservation policy, to be effective and sustained, needs to be based on the information we have, our evaluation of its quality, and our estimate of the uncertainties. Science’s essential role is to provide information of a known quality and make estimates about the uncertainties (so that future science can reduce the most significant of them). My role as a scientist and professional is to help make this process happen. Thus, I produce, interpret and evaluate information and estimate the likely difficulties and their importance. Inevitably, to be effective, I must also do that in a context and on topics that are also culturally, socially and politically important.

      You label people unfairly when you use terms like “naysayer semantics” and “contrarians” just because they have different opinions to yours. Yours is not a constructive contribution to the debate.

      Actually the scientific work I referred to [Past, present and two potential futures for managing New Zealand’s mammalian pests by John Parkes, Graham Nugent, David M. Forsyth, Andrea E. Byrom, Roger P. Pech, Bruce Warburton, David Choquenot] does actually conclude that predators cannot be eradicated from New Zealand and that trying to do it might be counterproductive:

      “The national scale pest- or predator-free aspiration is not currently (and may never be) feasible and risks diverting resources from more optimal solutions, as occurred with the ‘last rabbit’ and ‘last deer’ programmes promoted last century”

      and they recommend almost exactly what I do: ” We consider some form of nested management across space and over time to suit these different parameters, at least in the major areas of indigenous habitats, will at present provide the best way to improve outcomes. All this pest management can be done based on the current wildlife management toolkit, such that improvements in efficiency will allow more areas at larger scales (and more pest species) to be added to the portfolio.”

      Dave – I think you need to be more circumspect before you push the REPLY button.


      • Wayne

        I don’t think you have correctly represented Parkes et al conclusion and your lack of scientific rigour is disappointing. You have said they: “actually conclude that predators cannot be eradicated from New Zealand and that trying to do it might be counterproductive:” They did nothing of the sort. The relevant text from their paper is: “Unless we develop new tools, gain the social licence to use them everywhere, develop much more cost-effective tools and systems to prevent most reinvasion and to detect and kill survivors and invaders, local elimination of pests from unfenced mainland areas will usually be undone by reinvasion.”

        There a big void between your “cannot” and their ” unless we develop”.

        • Sunny,

          You quote me (use quote marks) incorrectly. Nowhere in the weblog post do I use the following words: “actually conclude that predators cannot be eradicated from New Zealand and that trying to do it might be counterproductive”.
          Thus, you are misquoting me.

          However, I do interpret the text you quote from Parkes et al. as meaning that predators cannot, at this time, be eradicated from New Zealand. Parkes et al. outline an alternative strategy that seems more feasible: i.e., a national network of biodiversity sanctuaries. It does seem to me to be counterproductive to ignore a feasible strategy and invest in an impossible one.


  • Hi Wayne:

    Thanks for your reply. If we’re discussing labels, I’d add that branding people as “science deniers” simply for supporting a worthy aspiration is every bit as unhelpful, as is dismissing their enthusiasm as “extremist, absolutionist, and jingoistic.” My failing is that I responded to such taunts with like, so mea culpa. I always find it amusing when the defenders of the Victorian vision of New Zealand as a vast egalitarian hunting estate for the working class accuse visionaries of wanting to turn back time. I stand by my statement about semantics, which I notice you invoke again to create the false impression of agreement between the authors of that paper and your prescription for fenced sanctuaries. In my interpretation, they are not supporting your position to the extent you claim, but are referring to a strategy that might well be compatible with the kind of rolling front or join-the-dots strategies that have been propounded. Similarly, to fixate on eradication is a straw man that exploits what is, I concede, a flawed brand. We all know that, even if you don’t eradicate a pest, getting it down to the last two or three per cent still secures enormous gains for threatened species. And it that may well be the hard limit that PF2050 runs up against, but it will still have been an utterly worthwhile thing to do. You and I do agree on some things: like you, I do not believe that New Zealand society is adequately disposed, equipped or briefed to properly evaluate measures like gene editing. However, I don’t present that as a straw man simply to champion my pet proposition. My feeling is that we urgently need to embark on a parallel programme of psycho/sociological research to inform PF2050. There are other gains we could piggyback as well: we also possibly agree that science education and attainment in New Zealand schools could be much improved: the social enthusiasm for PF2050 could be harnessed to encourage just such a benefit. The media needs to lift its game in the way it reports science — that could be a coincidental benefit too, if we apply just as much resourcing to social research. I regard these things as coincidental opportunities, not reasons to put what’s left of biodiversity behind a fence, which, in my view, is defeatist and sets an abysmally low bar in terms of a future for wildlife, well below what we know we can achieve. We can and will do much better than refugee camps for endangered species.

    • Thanks Dave – it looks like we agree on very much and around the detail of the debate I haven’t anything more to add.

      On the topic of labels I agree with you. “Science deniers” is a bad term to use. My tongue was firmly “planted in my cheek” yesterday when I used the phrase in my opening speech because I was sitting next to James Russell who used the term in a recent publication [“The Rise of invasive Species Denialism” in Trends in Ecology & Evolution, January 2017 Volumne 32, Issue 1, see also: to describe people like me who are critical of Invasion Biology and policies for predator eradication. I wanted to communicate just how inappropriate it is by turning its use around to describe pro-PF2050 supporters. I am sorry if my attempt at humour was not understood as such.

      Lastly, my use of the terms absolutionist, jingoistic and extremist was in reference to the PF2050 policy, not people.


    • Hi Dave – good to see you engaging with this discussion.

      I agree that labelling people ‘science deniers’ for expressing a different perspective (even a ‘crazy and ambitious’ one) is not conducive to open debate. As Wayne noted, it was offered up at the #crazyambitious conference as a friendly dig at James’ recent paper on this topic which was heavily criticised through reply articles in the following issue of the journal. I had a chuckle but I appreciate that it was a bit of an in-joke.

      Not sure what you mean when criticising ‘defenders of the Victorian vision of New Zealand as a vast egalitarian hunting estate’. If aimed at Wayne that seems misdirected. Is this intended more as a caricature of hunters? It seemed out of place in your reply.

      For me, holding up the notion of eradication – which is the lynchpin of Predator Free 2050 – as a ‘straw man’ is quite a remarkable piece of semantics itself. No, we don’t all agree that when referring to eradication the Government really just means control to low levels. If it is, it’s news to me and, if accurate, I’d like the Government to be explicit about that concession. There was no indication of this at the conference.

      I disagree that pursuing the Predator Free 2050 goal (which is fundamentally about eradication of these five species) regardless of any realistic hope of success is sensible. For one thing, failure could have perverse consequences for many of our more measured and sustainable conservation initiatives. And, as I think you agree, the means of achieving the goal (ie, further use of poisons, gene editing) are likely to be highly contentious. We have to be careful how hard we push people.

      I think we all agree that more social research is needed on how palatable this sort of goal is. Different measures to bring about the goal also need to be tested for their social acceptability. But we also have to be open to the possibility that that research may show that nationwide eradication is not going to be considered acceptable. There is no point in heading off ‘educating’ people on how worthwhile the goal is only to later find that people widely disagree. The social research therefore needs to come first.

      I appreciate where you are coming from when you describe people with different perspectives as ‘defeatist’. For you, perhaps there is a single, unshakably valid position on how we should understand and value our biodiversity. I do see where you are coming from with that belief. It makes sense to you perhaps to frame those who disagree with you as ‘giving up’. Personally, though, I’d like to see a wider acceptance in the industry of the fact that there is no one right way to think about this stuff. All our positions on nature are based on value frameworks informed by our own unique backgrounds, interests and research.

      By all means let’s have a bit of back and forth with this stuff, but we don’t have to construct different perspectives as ‘the enemy’ all the time. We all have good intentions here. We just differ a bit (OK, sometimes a lot) on what the end is and how we might choose to get there.

      Once again, good for you for engaging with this debate – it’s exactly what’s needed.

  • We seem to see so many articles talking about flawed and biased science. In more modern times it is such a disappointment that one’s ethics and morals seem so easily swayed and often driven by the mighty dollar.
    As a person with nearly 50 years of regularly enjoying the NZ outdoors I am very concerned that the New Zealand I have always known and enjoyed is fast disappearing and I don’t believe it is due to those named by some as ‘pests’. I believe the huge loss of native habitat has contributed greatly to the loss of of our native bird species.
    What is hard to understand is how our native birds are in decline yet the non native bird species seem to be thriving. This lack of understanding is made even more difficult to fathom when we consider that the non natives are subjected to and living with the very same ‘pests’ which we are told are decimating the native birds.
    So it is not hard to see why so many don’t support yet more poison in our environment.

    • Neville Du Fall says:
      > What is hard to understand is how our native birds are in decline yet the non native
      > bird species seem to be thriving. This lack of understanding is made even more
      > difficult to fathom when we consider that the non natives are subjected to and living
      > with the very same ‘pests’ which we are told are decimating the native birds.

      The explanation is simple: introduced species have evolved in the presence of these predators, and have evolved defences against them. As an example, consider the alarm call of a blackbird. Our native species have not been exposed to the same predators, do not have defences against them, and often don’t even recognise them as a threat!

  • With this debate I think we are dealing with a paradigm shift and I am glad to hear that Invasion Biology is being questioned. Because the paradigm that “Predator- Free NZ’ is based on seems to be more like the “restoration ecology” – a vain attempt to restore NZ ecology to some purist past state. This is delusional. Nature is dynamic and ever changing. With climate change the species mix and new “alien invaders” will inevitably arrive.

    Yes Wayne, PFNZ2050 is definitely a “greenwash” of the highest order of hypocrisy from the current government, which is encouraging deep sea oil exploration, coal mining, intensive industrial agriculture – destroying habitats and water purity and risking pollution disasters. They don’t care about the environment. The very name “predator-free NZ ” is risable and exposes the scientific ignorance of those who conjured and PR-ed it into existence. Moreporks/Ruru are predators, insectivorous birds are predators, the at-risk NZ falcon is a predator. Actually a 1080 drop wiped out a group of Karearea on a friend’s land. They have never been seen again since the aerial 1080 drop . The “unintended consequences” of a corporate-driven conservation agenda. Apologists for the 1080 conservation juggernaut like Mr Hansen, need to put their chin in their hand and have a wee think.
    What on earth is D Hansford talking about when he says:
    “My feeling is that we urgently need to embark on a parallel programme of psycho/sociological research to inform PF2050.” Sounds like a brainwashing campaign. This is the problem when conservation crosses over into evangelism.
    Kia kaha Wayne.

    • Hear, hear, Stephanie. That comon birds are breeding very well thank you is a conundrum. You say native birds have not evolved to cope with the pests. Most creatures on Earth are highly adaptable,and our native birds can put up as good a fight, if not better, than common birds, it is a natural instinct, but it is the small birds – tomtits, fantails, robins, that are at a disadvantage, but no more so than the introduced finches. Both sides of the 1080 debate refuse to remove their blinkers. Those that have deeply thought-out solutions, ideas on the subject are not given a chance. Like the Graff brothers, the pro-1080 movement choke over them but the Graff brothers are sincere people that have got out there and observed, and taken their observations to the public to see. I have seen blackbirds’ eggs get predated by rats, and those blackbirds have had another clutch, perhaps several more, again in the same season. Perhaps it is stochastic, where at least one clutch will survive in the circumstances, and if not, maybe next year there wont be as many rats to fight off. As for a predator-free NZ, you have stated it superbly, Stephanie. Humans are the worst predators of the lot, but looks like we will get a free ride in predator-free NZ. It is impossible to de-couple humans and rats. Canada may not have rats in the west but it is fighting a huge losing battle, with rats re-invading rubbish tips at prodigious rates. I don’t think there is one global example of rats being totally removed from a human population, and unless we are made to endure some horrific methods (e.g. the blanket aerial spraying of West Auckland for a moth a few years ago, people told emphatically by health authorities that the pesticide was safe to humans, but there was , and perhaps ongoing, many people getting ill effects in one way or another ) it isn’t going to be NZ

  • Both Dr Linklater & Dr Steer’s work are a breathe of fresh air in otherwise totally alienating, immature & archaic debate.
    One thing I would add is – Jamie – it’s not only the social research that is needed, alongside the potential consequences of pursuing the fantasy that is PF 2050 – but the public health impact too. The continued aerial poisoning of our land & water needs to stop & valid comprehensive epidemiology data needs analysis. 63 years of existing ineffective ‘pest’ control has undoubtedly done significant damage on many environmental levels – ‘ramping it up’ without rigorous health & safety assessments is utterly irresponsible of our Government.

  • Mary is right to worry about the human health and safety aspects of the increasing use of 1080. Initially 1080 was approved as a nuclear stop-gap measure to give us time to find a less polluting way of saving our forests from being stripped bare. Now we recognise we are out of this immediate danger, possum numbers fell from 70 to 30 million over night and the 1080 spread has simply increased and increased. Govt has taken steps to speed up the flow of 1080 baits from factory to forest. Once important measures like talking with all affected parties prior to a drop to ensure they know to keep their dogs muzzled, and keep an eye on the children and the animals in the back paddock, making sure no one drinks from poisoned streams, or eats poisoned meat. There are a string of regulations and standards set in place to ensure 1080 is spread “safely”. Regional councils were able to enforce these regulations and standards, through their interpretation of section 360(10(h) subsection 15 of the RMA. Now that this power has been removed from regional councils there is now no government body authorised to ensure human or animal safety during 1080 drops. For country folk who live downstream from a 1080 drop there is nowhere left to turn when things go wrong during and after a 1080 drop. Government has cast all safety measures to the wind saying the Environment Protection Society will take over from councils but the EPA is not authorised to police the use of any of the toxic products whose release they have approved. Brace yourselves.

  • Just where is our intrepid media in this whole debacle. Surely the contribution by the media can be improved upon and atleast make some effort to provide both sides of the puzzle. To date their feeble efforts have amounted to repeating jingoes drip fed to them on a regular basis by people who think dropping hundreds of millions of poison baits from aircraft is the only solution to a perceived problem. The risks to our exports is huge from the poison in products such as honey, produce and dairy. I saw a sign on a bus in Wellington recently with beehives and poison warning signs in very close proximity. This is occurring in many rural areas. 1080 is an insecticide that contains up to 30% sugar to attract possums to it. It also attracts bees and there is clear evidence of 1080 in beehives and many hives have been wiped out. Cinamon flavoured and 1080 infused honey anyone ?. How long before our international customers start to question the assurances that all is well in the garden of clean, green poisons. The inhumane killing of animals and birds by 1080 is hidden away from the general public because of media apathy or lack of intestinal fortitude by our editors. Animals like deer take days to die from 1080 and up to three weeks to die from brodifacoum. Perhaps we need to consider a new tourism venture that takes people to areas where ecocide has been most effective.

    • Your concern here is clear Geoff, 1080 is a tricky subject. The PCE, DoC and MfE have done a lot of research and determined that, for now, it is the best tool we have for protecting native flora and fauna. I think the dearth of media reporting is due to a number of reports (particularly the 2011 report from the PCE) laying out the evidence and research – with an honest acknowledgement of the trade-offs. The 1080 milk powder threat probably also lead to a loss of public sympathy for those who oppose the use of 1080. As Wayne points out in the article, there is a risk regarding international perceptions. For what it’s worth, I’d be keen to see any recent research on 1080 residues in honey, particularly in relation the current bait formulations. As an aside, what do you think about the recent discussion on the use of gene editing for predator control?

  • Just where is our intrepid media in

    One source of discussions in the media on gene editing for predator control is Radio NZ – they have a series of interview panels on this. (I have been meaning to write on this myself, but clearly have not gotten to it!)

    A couple of quick thoughts (general observations by the way, not directed at any one person or the author):

    To me, “let’s stick with the ‘old’ way” has never been a particularly good argument, even if it (initially!) looks “right” as it too often seeks to not really look at the options carefully but make sweeping statements. It’s also tends to rely on a rosy view of what the past is, and is vulnerable to ideological influences.

    Similarly, I generally don’t like the one approach/technique or the other one line of argument — it seems to me it’s almost always better to find out what each does best, and apply them as appropriate.

    I’m familiar with these lines of arguments from other topics, esp. re GMOs — c.f. GMOs “vs” ‘organic’ farming. Just my humble opinion and all that, but there’s altogether to much either/or, or us/them in these people talking about these sorts of topics.

  • Hi
    Just going to add my 2 cents worth here. I have been involved with hunting and trapping pests on and off for most of my life,
    1080 poison has been wipeing out our native birds insects etc for the last 60 years, the nz govt /doc have been doing their best to keep the truth out of the media about what basically we can call genocide of our natives from that 1080 and brodifacoum poison , the facts are all there that clearly show 1080 does not work, birds are not thriving where 1080 has been repeatly dumped,set trapping, kill traps and bait stations work, where ever trapping is used you have good bird numbers,,where ever 1080 is used we have silent forests,,,thats a proven fact. most of the country that has 1080 and brodifacoum poison dumped on it can be trapped useing one form or another,or all, but unfortunatly we have politicians,councills etc the have shares in the 1080 factorys,,thats a fact.. so of course we will have corruption,coverups etc,, doc have been proven to lie when it comes to what has and has not happened with regards to 1080 and brodifacoum poison. Test results obtained from doc through an oia request show that most of our bird speicies have had large numbers of each killed from 1080 and brodifacoum,doc no longer tests dead birds for poison,,,, why?? so you don’t have a recorded positive,,,thats why., , recently here in Hokitika we were informed that kea were eating the 1080 prefeed baits that were recently dropped nearby in the perth valley,, part of this insane idea of eradicating every pest from the valley useing 1080,so doc or zip or whoever is in charge of the operation decided that they add a deterant to the bait and shoot a heap of Thar and dump them in the keas habitate..hopeing that the kea won’t touch the poison baits and would eat the Thar,,,,,hopeing???,,,,,,this is just stupidity ,,,anybody who knows the kea knows they will still eat the bait, and what about the other birds???W don’t need people with this hit and hope attitude with 1080 in charge of our wildlife,a few people who are involved with this operation are themselves saying its a huge waste of money and that they could have trapped the valley ,,and know that no birds are NOT dying, for less money than whats been wasted in the perth, just broad casting one of the most deadly toxins known to man all over our forests and just hopeing it works is nothing short of insane,60 years of this proves it does not work. it kills the very animals we are trying to save,
    We have proven solutions to the problem, but we have politicians and buracrates who are out for them selves and there mates profit, we have news papers who refuse to print anything that does not go along with what the beuracrates want or with what the editor believes in, we have heads of the doc departments who tell out right lies to the public about the damage that 1080 has done and who refuse to listen to any proof that it does not work or accept any proven evidence that they are wrong….with arrogant people like this in control of our wildlife we are going to see alot more or our native speicies become extinct.
    We have an export comodity in our forests that was kept under control by selling to export markets..thats deer, the export market was detstroyed by 1080 poison,, deer feed familys, create jobs, are easily controlled by ground hunting and helicopters, that was proven …they don’t destroy our wildlife or fauna when kept under control, no more damage than what the moa did, but now we have the half truths and lies being put out in the media that they are detroying our forrests etc, that is just absolute lies used to try and get the public on board with this total eradication of all non native animals in our forests . the pest free by 2050 is just an obsurd form of propaganda. We are not going to see a change in our native birds speices survival rate untill the people in charge accept that they haveto drastically reduce the use of 1080,and drastically increase the use of trapping,kill traps and bait stations,,,its that simple,,,boots on the ground .

  • Its good to see this issue being talked about in a different manner than on FB. Educated and informed versus the opposite with a lot of misguided ‘facts’ flying around social media from both sides of the issue. However, the use of 1080 is certainly gaining traction in NZ and overseas. This issue has already landed on other shores. Both in social media and in the papers. Its touted as NZs dirty little secret. Already people and the media are questioning the validity of our clean green image and the dodgy 100% Pure lie. The foreign journalists and publications are not being stymied or force fed ‘1080facts’ (according to DoC) and are undertaking world research instead of just research done in New Zealand where there is 1. A conflict of interest and 2. Conflicting evidence about the use of 1080.