Response to articles by Dr Jo Pollard

Response to articles by Dr Jo Pollard:

1/ http://business.scoop.co.nz/2011/05/24/1080-poison-science-and-facts/
2/ http://www.scoop.co.nz/stories/SC1105/S00067/1080-poison-science-and-facts.htm

Dr Jo Pollard claims to have put the science used to justify the continued use of 1080 “under the microscope”. Unfortunately, it appears that she may have forgotten to take the lens cap off, say Paul Livingstone, TB Eradication and Research Manager at the AHB and Mike Slater, DOC West Coast Conservator.

If everything Dr Jo Pollard claims in her article is to be trusted, it is truly remarkable that the Environmental Risk Management Authority (ERMA) would have approved the continued use of 1080. However, that is precisely what it did in August 2007.

Dr Pollard’s total opposition to the continued use of 1080 puts her very much into a minority amongst the dozens of scientists who made submissions to the ERMA review. Since 2007, she has indicated that she has dedicated herself to challenging the validity of the vast body of scientific research presented in support of 1080. More often than not, the result has been little more than a pseudo-scientific diatribe demonstrating no academic objectivity or scruples.

A case in point is her disingenuousness in failing to put any qualifications around the statements that “1080 is toxic to species of all forms of life” and that it “spreads very fast in water”. As any scientist would tell you, without the qualification of dose or dilution, the exact same unqualified statements could be made for table salt. In fact, they could be made for practically any substance on Earth.

Similarly, she cites “anecdotal reports” about links to breast cancer before admitting that there has been no research whatsoever on this - hardly the kind of statement one would expect from a competent scientist. Interestingly, although not specifically tested in relation to breast cancer, 1080 has shown absolutely no cancer-causing action in any of the standard carcinogen tests conducted to date.

Of course, none of the agencies using 1080 to control pest mammals for the benefit of conservation or disease management deny that 1080 is extremely toxic. Indeed, its particularly high toxicity to mammals is what makes it such an effective poison for use in New Zealand, where the only native mammals are bats.

Although birds, invertebrates and other animals are certainly not immune to the poison, the risks are greatly mitigated by the lethal doses they need to consume. There is no evidence that the toxin has a cumulative effect, or persists in the food chain. In fact, one of the most remarkable properties of the toxin is how quickly a sub-lethal dose is metabolised and expelled from the body. The risks to non-target species are further alleviated by the extremely strict regulations around how the toxin is used. For example, decades of extensive research and operational experience have enabled us to improve the efficiency and minimise the risks of aerial 1080 operations through:

• A reduction in the average quantity of poison bait used per hectare from 30kg/ha in the 1970s to just 2kg/ha today
• Research into more efficient dispersal methods, such as cluster sowing, that may further reduce the quantity of bait used by up to 75 per cent
• The use of GPS technology to make the deployment of baits accurate to within a couple of metres
• The routine use of cinnamon lure to attract possums and repel birds
• The routine use of carefully-screened cereal baits

The reality is that, as ERMA concluded in its reassessment, the benefits of using 1080 to control introduced species that are destroying our endemic wildlife and spreading bovine TB outweigh the adverse effects.

Despite this, Dr Pollard appears to deliberately misrepresent both fellow scientists and the findings of the ERMA committee in an attempt to bolster her beliefs.

Take her assertion that a 1080 operation in 1998 in the Okarito Kiwi Sanctuary caused the deaths of 14 rowi chicks four years later. In fact, the plague of rats and stoats in 2002 that killed the chicks was caused by a massive forest fruiting event of a magnitude that had not been seen for decades. If Dr Pollard had done her research she would have found that, at the time, DOC were running the largest stoat trapping operation in the world at Okarito. The seriousness of the plague was such that even 1500 stoat tunnels were not enough to protect the chicks. The last two survivors were removed to an island to prevent them being killed as well.

Similarly, her criticism of wildlife management at the Tongariro Kiwi Sanctuary missed the point that this forest supports sufficient kiwi and whio (blue duck) to be managed as both a ‘kiwi sanctuary’ and as a ‘whio security site’, yet it has been subject to one of the longest sustained aerial 1080 treatment regimes of any site in the country. In fact the survival of whio and kiwi juveniles was significantly better than normal for the two summers following a 1080 operation in 2006. In comparison, kiwi and whio have completely disappeared from many places that have not been fortunate enough to have received such treatment.

In her claim that “numerous studies have shown that possums are principally herbivores” she does nothing more than provide ammunition to the ‘possum apologists’. In fact, both current scientific research and photographic evidence points to the fact that possums are “opportunistic omnivores” (Cochrane et al) that will consume invertebrates and native birds and even scavenge from deer carcasses as part of their regular diet.

She makes a similar error in her statement that “livestock can be vaccinated against TB” when over 30 years of research into the development of a TB vaccine have failed to find one that is effective in preventing infection following experimental challenge with M. bovis.

It is important to realise that this evidence is not “wishful thinking and casual observations…masquerading as science” as Dr Pollard would have us believe. In fact, it is cold, hard data that has been captured by carefully-designed experiments using well-established, internationally-accepted field study methodologies, undertaken by experts in their field. More importantly, it has been accepted as such by the ERMA committee.

Unfortunately, Dr Pollard’s treatment of the ERMA committee’s own findings is no less contemptuous or misleading.

For example, she cites a lack of “factual support to demonstrate the efficacy of aerial compared with ground application of 1080” as a flaw in the justification for the continued use of 1080 poison. The ERMA committee was naturally far more interested in a comparison between 1080 and alternative available toxins and states clearly that it “accepts the applicants’ view that if ground control methods only (1080, trapping and cyanide) were used, then the longer term benefits would not be realised and the cost of vector control would continue to increase into the future” (point 9.7.35).

Similarly, while her claim that the ERMA committee did not support “the suggestion that trade is significantly reduced by not having bovine TB-free status” is correct, it deliberately fails to acknowledge that the same committee stated that “a widespread (TB) outbreak would have a significant cumulative impact in terms of the New Zealand economy” (point 9.7.13).

She even goes as far as to claim that the report left the AHB’s arguments for the continued use of 1080 to kill possums “in tatters”, when the ERMA committee actually said that “the aerial use of 1080 is clearly an important tool for the national possum control strategy which greatly reduces the possibility of a further major national (TB) outbreak in the future (point 9.7.13).

For some people in New Zealand, the 1080 debate has become an extremely emotive one fuelled, in part, by deliberate misinformation and hysteria. As the ERMA review acknowledges, robust science therefore has a critical role to play in ensuring the facts around the safe use of 1080 are not overshadowed. Pseudo-scientific articles like Jo Pollard’s add little, if anything, to the informed debate we need.

Paul Livingstone is manager of TB eradication and research at the AHB. Since 1973, his work has involved all aspects of controlling bovine tuberculosis, and he has been the acknowledged scientific leader of New Zealand’s bovine TB control programme for more than two decades.

Mike Slater has been the Conservator for the Department of Conservation on the West Coast since 1996, and has been involved in conservation management for 34 years. The Department manages 1,912,680 hectares of land on the West Coast, and manages pests at key sites to protect and maintain native species. The Department is acknowledged internationally for its leadership in successful conservation programmes.

ENDS

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