Poisoning a priceless treasure
Members of the older generation may remember the world-wide excitement in 1948 when Dr Geoffrey Orbell and two companions discovered a small group of takahe (notornis hochstetti) in the remote Murchison mountains of Fiordland. These large, ungainly, and brightly coloured birds, which are somehow reminiscent of Lewis Carroll’s dodo, were previously thought to have been extinct for more than 50 years. Dr Orbell captured two birds in a net, took photographs and then released them. He returned to civilisation, according to one correspondent, “in a state of ornithological ecstasy”. If Dr Orbell were with us now, I imagine the recent reports of takahe deaths caused by 1080 poison, administered by our own Department of Conservation (DoC), could well have induced a state of ornithological apoplexy. Who could blame him? We human inhabitants of these isles are after all the guardians of this priceless treasure, known to Ngai Tahu as a taonga and enshrined as such within the Ngai Tahu Claims Settlement Act of 1998.
Until now much of the takahe news has been positive. DoC has undertaken a programme of relocating birds to island sanctuaries and breeding them in captivity with considerable success. There have been deaths – most notably 4 birds killed accidentally by DoC contractors in 2015 – but recently there has been an encouraging rise in the population from 263 in 2013 to 418 announced in 2019 by the Minister of Conservation, Eugenie Sage, with considerable fanfare. It must therefore have come as a nasty shock to many bird lovers to read in ‘Stuff’ on the 26th August 2020 that 3 takahe had died after an aerial 1080 drop in Kahurangi National Park at the top of the South Island. All deaths have now been confirmed on toxicological testing as definitely due to 1080 poisoning – a result that the Takahe Recovery Programme Operations Manager Deidre Vercoe described mildly as “disappointing”. Three among 18 monitored birds represents a whopping 16% mortality for the operation. Surely more disastrous than disappointing. How and why did this happen?
Takahe were relocated to the Gouland Downs region of the South Island’s Kahurangi National Park in 2018 to try to establish another mainland population outside the Murchison mountains. Consistent with DoC’s preference for using aerial 1080 to control predators, the region was subjected to a poison drop on August 16 and 17 of 2020. There must have been some quivers of doubt as to the wisdom of dropping a non-selective and deadly poison directly into this new takahe habitat and accordingly an exclusion zone of 587 hectares was defined where no bait was applied. Takahe were moved into this region prior to the drop but apparently some birds simply wandered out into the danger zone and consumed the poisoned bait.
This shameful event was entirely predictable. Takahe, along with many other native birds, including the fantail, the South Island robin, the tomtit and the kea, are likely to be very vulnerable to 1080 poison. Nobody had actually dropped 1080 on top of them before so we did not know that for sure. Now we do. Poisoning large areas within our national parks is reckless in the extreme but is always justified by DoC’s blithe assertion that 1080 will kill predators effectively and that this reduction in predation will “justify” bird deaths from deliberate 1080 poisoning. The evidence for this is flimsy at best and non-existent in the case of the takahe. What is more, why shouldn’t a predator such as a stoat also simply shelter in the exclusion zone while the noisy helicopters send down their deadly rain of green pellets, and then saunter back out a few days later to carry on predating? This exclusion zone would not have been protected by a predator proof fence, and neither would the 1080 zone. Did DoC really expect wild fauna to stay within their proscibed regions just because they wanted them to?
If this were an isolated event it could be forgivable but it is not. Kea deaths from 1080 continue to be reported and this is now another threatened species. In March 2020, 6 kea recovered from the Matukituki valley in Mt Aspiring National Park were reported to have died from the 1080 toxin, (post-mortem findings from Massey University) following an aerial operation on 11 February. In total 12 kea were tracked after the poison drop so this represented a 50% mortality rate, reported again as “upsetting and disappointing” by the DoC representative (particularly for the kea one would assume). The year before, 2 out of 13 kea deaths were attributed to 1080 after a poison drop on the West Coast. According to independent scientist Dr Jo Pollard, “using DoC’s own data, we can estimate that each poisoning operation will kill an average 12% of kea. During the most horrific example DoC managed to kill 78% of the tracked kea population (7 of 9 kea monitored at North Okarito).”
It is not too late to cease and desist as far as the use of 1080 is concerned. Trapping can control predators in many areas. A maxim of bioethics is “Primum non nocere” (First do no harm). Lets change our approach to pest control now and ditch the use of this deadly poison before our rarest and most precious birds are consigned to extinction.
Fiona McQueen MBChB MD FRACP
Consultant Rheumatologist, Southland Hospital
Author: The Quiet Forest: the case against aerial 1080 (Tross Publishing)