Opinion: examining the ongoing debate about 1080

Few topics are as polarising or divisive in New Zealand as the use of aerial 1080 for the control of introduced mammalian pests.

The media is inundated with alternating viewpoints, with organisations such as the SPCA (anti-1080) and Forest and Bird (pro-1080) seemingly at loggerheads. For many people, the 1080 debate is very confusing; and with strongly held opinions on both sides, understanding of the actual issue can be shaped by misinformation, misunderstanding or even mistrust of the organisations involved or the information they put out.  

So, why do we use 1080? Is it really necessary? Isn’t there a better option?

The short answer is that New Zealand’s native flora (plants) and fauna (animals) are facing a catastrophic threat from introduced mammalian predators. As outlined by the Department of Conservation (DOC) in 2017, of the 5,819 species of native plants and animals, more than half are classified as At Risk or Threatened. This puts our native wildlife amongst the most threatened on the planet; 80% of our bird species are in bad shape – and 50 species have already achieved extinction status.  

These are the key factors: 

  • New Zealand’s unique flora and fauna have evolved in the absence of any terrestrial mammal species; aside from our native bats. Our fauna has been unable to adapt to the rapid influx of mammalian species that we humans have inadvertently – or, in some cases, deliberately – introduced to New Zealand.  
  • Our birds are being eaten by stoats and rats, and our forests are being eaten by possums. Nine out of 10 North Island brown kiwi chicks born in the wild will die before they are a year old. 25 million birds are being killed each year, with a single rat or stoat able to kill hundreds of animals a year.  
  •  Possums are the primary vector for bovine tuberculosis; a disease that threatens our primary sector; and, if left unchecked, can impact the export of beef, deer and dairy products.  

In some parts of New Zealand, the current best option to mitigate the disastrous effects of these pests is to use 1080.  In remote back country forest habitat, the best practice is aerial dispersal of baits containing 1080. A single 1080 bait weighs 12 grams – similar in size to a Brazil nut.  

Baits largely consist of cereals from various grains and other non-toxic ingredients. Each bait contains 0.15% 1080 (think one quarter of one grain of table salt). Baits are spread from a large metal bucket suspended under a helicopter, and current industry standard sowing rates aerially deliver, on average, four of these baits over an area the size of a tennis court.  This distribution is regulated by precise GPS-guided systems.

On face value, dropping toxic baits out of helicopter over thousands of hectares may not sound ideal, but the reality is that there are currently no other pest control tools or techniques available for landscape-wide control of possums, rats and stoats with the equivalent efficacy and cost-effectiveness  that 1080 can provide. It should also be noted that: 

  • 1080 is highly water soluble;  
  • It breaks down in the environment into harmless substances;  
  • It effectively controls the three most destructive mammalian predators; and  
  • It is relatively fast-working.  
  • 1080 is not selective, and its broad-spectrum toxicty is a disadvantage where non-target species (including native birds) access bait.
  • Dogs are highly susceptible to 1080.

New Zealand uses more 1080 than any other country. Fortunately, unlike most other countries, our only native land mammals are bats – 1080 is most toxic to mammals.

The aerial foraging behaviour of native long-tailed bats suggests that they are highly unlikely to consume 1080 either directly or indirectly. The lesser short-tailed bat, however, preys on ground-dwelling insects. This means these bats are susceptible to secondary poisoning through the consumption of insects that have been exposed to 1080 baits.

DOC monitored short-tailed bat populations during and after 1080 drops, in 2002 and 2017. These studies have shown that 1080 is a potential factor in the mortality of a small number of individuals. But the introduced mammalian predators that 1080 controls pose a major threat to short-tailed bat populations, and monitored populations have demonstrated increased survivorship overall following predator control. This indicates that 1080 operations have an overall positive effect on populations of both our native bat species.

Opposition to 1080 includes those who are against the use of toxins in the environment in any form, for any reason.  Some oppose the lethal control of any animals, and some say 1080 is inhumane. Some of the hunting community are concerned about deer, pigs and other commonly hunted species consuming baits and dying, and the risk to their hunting dogs which are highly susceptible to death by 1080. There are also those concerned about environmental contamination and those who have an inherent distrust of any initiative put forth by government organisations. This is not an exhaustive list, by any measure. 

Many groups opposed to the use of 1080 have called for an outright ban. In a January 2019 press release, the NZSPCA also supported this.  

Many of those who support the use of 1080 are often involved in conservation efforts, farming, native species restoration, and government organisations including the DOC and OSPRI. These government organisations are tasked with undertaking control with 1080, and numerous research institutes are busy studying its use and effects.  

Although there is a strong lobby group calling for the ban of 1080, without an effective replacement years of native species protection may be undone overnight which could see many native species extinct on mainland New Zealand within a short space of time. As University of Auckland Associate Professor James Russell (an expert on invasive mammals) stated on RNZ a few weeks back, “giving up 1080 would lead to an ecocide of huge proportions in New Zealand”. 

A large amount of peer-reviewed scientific research has been completed; looking at the effects of the control of pest mammals with 1080 on populations of native fauna, and its breakdown in soil and water.  

A comprehensive review of 1080 was undertaken by the Parliamentary Commissioner for the Environment in 2011, which summarises the huge body of research and literature already existing on the effects of 1080. The recommendation from this review was that “there are other pest control methods that are more suitable than 1080 in certain circumstances but on much of our conservation land there is currently nothing else that will effectively kill possums, rats and stoats”. 

It is difficult to have an open, honest, and factual conversation about 1080 between supporters and those opposing its use. Many people are so entrenched in their views that no amount of discussion, anecdotal evidence or scientific literature is likely to shift their positions.  

The conversation around the use of 1080 needs to move forward and one logical way for this to happen is to look at our current investment in research and development for both the refinement of this tool and the development of new complementary and replacement tools. Wouldn’t it be great if in 10 years’ time we were no longer debating 1080 use; and not because it was or wasn’t banned – but because we had been able to adequately invest in R&D and it was no longer necessary to use 1080?

Investment in new control tools certainly has, and is, occurring; but as with many conservation initiatives, a lack of adequate funding has hindered progress. Many control tools, such as gene-drive technology or advanced fertility control, remain at least a decade away.   

While we continue to hear a lot of criticism of 1080 and the call to ban this tool, the reality is that both the refinement of this tool and the development of new complementary and replacement tools and technology require investment in R&D above and beyond what is currently occurring. Without such investment, we will continue with the same argument for many years to come and more than likely also be mourning the extinction of more of our taonga. In the meantime, love it or hate it, 1080 is the best tool we’ve got in many situations in the very real battle to save our native species from extinction. 

For further information please contact Dr. Lee Shapiro

1 February 2019