By Erica Mather 17/06/2016

There is an increased likelihood that invasive species arrive in New Zealand from countries with poor regulation and low political stability, according to research published in Proceedings of the Royal Society B.

Research released this week from Victoria University of Wellington reveals that a country’s level of governance and development has a strong impact on their risk of exporting exotic species.  The findings suggest that by choosing international trading partners more carefully, New Zealand could reduce the costs of tackling invasive species outbreaks.

New Zealand receives imports from all around the world accompanied by unwelcome invasive species.  The invaders arrive from some countries more frequently than others.  Researchers set out to investigate the relationship between trading partners and the threat they pose to New Zealand biosecurity, as invaders are a leading cause of extinctions and a consequential loss of biodiversity.

Source: Proceedings of the Royal Society B

PhD student at Victoria University, Evan Brenton-Rule, considers the benefits of selectively trading with certain countries while acknowledging that it is an extreme approach:

“It’s worthwhile thinking about how international trade deals and a change in trading partners may impact the number of exotic species knocking on our country’s door. There are millions of dollars of control or eradication programmes at stake here, as well as potential biodiversity loss”.

According to co-author Professor Phil Lester, biological invasions cost New Zealand hundreds of millions of dollars a year.

“When you consider the amount that is spent on biological invasions in New Zealand, anything we can do to target our biosecurity resources and limit the number of invaders at our border would be extremely beneficial. For example, the eradication of just three small nests of the red imported fire ant into New Zealand cost in excess of ten million dollars.”

Fire ants attacking a mealworm. The eradication of just three small nests of the red imported fire ant into New Zealand cost in excess of ten million dollars. Credit Professor Phil Lester

The study utilised ten years of data on trade interceptions at the border from the Ministry for Primary Industries and analysed international trade volumes from Statistics New Zealand.  Over the period of ten years there were nearly 50,000 interceptions.  If New Zealand were to become more selective in its trade partners, the authors expect that the number of biological invasions would be nine times lower, saving millions of dollars.

The authors suggest that wider implications of their findings could include policy changes:

“Development and governance within countries clearly have biodiversity implications beyond borders… These results will be of considerable value to policy makers, primarily by shifting quarantine procedures to focus on countries of high risk based on their socio-economic status.”

Dr Stephen Goldson, a Principal Scientist for Biocontrol & Biosecurity at Agresearch emphasises that the current science-based biosecurity trade rules have been carefully developed over many years.  He describes a case-by-case approach, using scientific evidence to maintain a balance between ensuring biosecurity is protected and maintaining trade.

“While there may be some merit in taking such an observation into consideration, its broad application seems like a very blunt instrument that could greatly narrow New Zealand’s global trading opportunities and distort trade patterns. From an international-citizen point of view, does it mean that poor nations should languish in some kind of trade-vacuum in spite of what may be cost-effective production of valuable products and commodities?”

Featured image: CC Pixabay

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0 Responses to “Be careful who you trade with – New Zealand’s biosecurity threat vectors”

  • “According to co-author Professor Phil Lester, biological invasions cost New Zealand hundreds of millions of dollars a year”

    Citation needed! I think that this might be a wild overestimate! Only a couple of significant MPI responses per year are undertaken to eradicate new arrivals, each costing at most tens of millions. Of course it probably costs hundreds of millions per year to keep MPI functioning, but that money will be spent regardless.

  • Hi Stephen,

    Between 2006 and 2011, the Tomato-potato psyllid and it’s associated Liberibacter infection cost the New Zealand potato industry over $NZ 100 million dollars in terms of crop losses and extra control measures (Ogden, 2011). The costs increase yearly and 2010-2011 season alone, the estimated cost was around $NZ 28 million (Kale, 2011). This is just one industry, The psyllid also affects tomatoes and capsicums. The company I now work for lost over $5 million dollars in export revenue when this bug was discovered in New Zealand, due to the closing of borders because of phytosanitary concerns. Considering this is the damage from just one breach, biological invasions could indeed cost this country hundreds of millions of dollars.

    Kale, A. 2011. Report on the Economic and Business Impacts of Potato Psyllid on the Potato Industry.

    Ogden, S. 2011. Tomato potato psyllid and the research response.…/4%20Psyllid%20research%20in%20NZ.pdf.

  • TPP is “cherry picking” in the present context. You say “biological invasions could indeed cost this country hundreds of millions of dollars”, but Phil Lester was quoted as saying “hundreds of millions of dollars a year”, which is a much stronger claim. I still doubt that biological invasions cost the country hundreds of millions dollars per year on a regular basis. There simply aren’t enough invasions of comparable significance to TPP.

  • PS: I think that it is unfair to count the continuing cost of past invasions. If we were to, for example, count possums, rabbits, rats, etc., then sure the total cost to N.Z. would probably be hundreds of millions of dollars per year. But restricting trading partners isn’t going to decrease those costs. So, I was thinking more about the costs per year of dealing with new invasions, as only these costs could be avoided by restricting trading partners.

  • PS 2: OK, one more go to try for greater clarity:

    There is a chance that new invasions might occur, which could cost N.Z. greatly. Restricting trading partners would lower that risk, but would come with a cost of its own (i.e. less trade). So, where does the balance lie? Given that there haven’t been that many serious invasions into N.Z. in recent decades, and given that such invasions could still come by way of our main trading partners, I think that restricting trading partners probably isn’t a good idea. It is not helpful to quote people like Phil Lester who are making vague statements about invasions already costing N.Z. hundreds of millions of dollars per year. It gives the wrong impression.

  • I wonder what you would think of a Government law that introduces compliance costs of $25 million a year, every year for a particular industry. Would you consider four years of this law to cost the industry $100 million? Or would you forget about it at after a certain time period because it is not ‘fair’ to do so? What would that time period be? Also I think comparing current invasions with historical introductions that have been naturalized for decades is incorrect. Farming and production in this country has grown with those historical introductions, so there is no ‘extra cost’ as this has always been the cost of doing business in hort/ag in NZ. New introductions impose extra costs.

    I don’t think its unfair to count the extra costs that pile up year after year from recent invasions. After all, in a cost benefit of TPPA vs biosecurity, surely you’d look at the long term costs and benefits over decades?

    These are real, additional financial burdens on farmers and producers. Kiwifruit are still counting the cost of PSA. All growers who produce solanaceous crops count the extra costs of TPP, year on year form when it was introduced. The whole country freaked out when Queensland fruit fly came into Auckland, and over $15 million was spent on eradicating it (1). It cost $65 million to eradicate the painted apple moth in 1999 (2). A study by HortNZ in 2006 estimates the cost of an established fruit fly population at $800 million in the first year in the Bay of Plenty ALONE (2). Another study for the kiwifruit industry models different scenarios based on market responses (3). In the best case scenario, using previous market reactions to incursions and assuming eradication is $2million, in the worst case scenario, with wide distribution of the pest, it would cost the fruit industry $430 million a year in extra compliance and control (3).

    Also PSA, TPP, Liberibacter and the fruit flies are all major incursions that have happened within the last decade. The claim we have no major incursions in decades is incorrect

    The introduction of exotic species through biosecurity breaches increases the compliance cost for meeting the phytosanitary requirements for our major markets and risk closing those markets to New Zealand permanently. It risk crop losses, reduction in the volumes of export grade produce and increased control measures. If spotted wing drosphilia got into the country, the compliance costs alone (when/IF we managed to reopen our borders) would be huge, let alone crop losses and extra control measures. If any of the aforementioned flies gets into NZ, it would end all fresh fruit exports into Japan. That is not an insignificant cost.

    Now, to your claim that these costs would be hugely outweighed by the benefits of something like the TPPA. I am genuinely interested in what it would be as I am on the fence about it’s cost/benefit. Care to provide maths or references?


  • Gotta dash now, but you said “The claim we have no major incursions in decades is incorrect”

    I made no such claim! I said ” there haven’t been that many serious invasions into N.Z. in recent decades”.

  • OK, I didn’t have things quite clear in my mind when I started commenting here. I’m not so much questioning the amount that invasions cost NZ per year (though this figure will depend on how far back one goes, etc.), but rather the relevance. In order to judge the merits of the proposal, we need to know two things:
    (1) the likely cost to NZ of lost trade resulting from the restriction of trading partners; and
    (2) the likely savings from preventing future invasions directly from countries falling under the restriction.
    We probably also need to consider the cost/benefit analyses for alternative proposals (like trying for greater border vigilance at this end).

    I suggest that (2) above is the “thorny one”. There haven’t been that many significant inavsions in recent decades, eradication can and has been achieved in at least some cases (which costs, but it is not an ongoing cost), and we don’t really know how invasions like TPP got here. It might have come directly from a major trading partner, particularly if they haven’t also restricted their trading partners, and if all major countries cut off trade from minor countries, it could significantly contribute to the economic collapse of the latter! It seems to me that there are just too many big unknowns in the equation, and the current cost to NZ of invasions is rather a red herring.