As a point of clarification, the industry hasn't requested that we go nowhere near the coast. They've indicated that their key risk to mitigate is that no bait enters the ocean. The bait ‘safe line’ approach described in Tom Agnew’s presentation is how we will minimise the risk of bait entering the water during the proposed pukunui recovery operation.  

It’s worth remembering here that the proposed operation is a suppression operation. We are not seeking to completely remove target predators, only to reduce their numbers to provide some protection to pukunui during their nesting season, while they are most vulnerable.  

We know that with this method there will be some gaps between the effective coverage line and the coastal marine environment, and that some rats are likely to survive in these areas. This is a key difference between an elimination operation and a suppression operation. With a suppression operation, we know that reinvasion will occur over time.  

In the future context of Predator Free Rakiura, we are trying to remove every last rat, so we will need to ensure we target all rat habitat on the island, including the coastline. That is why research around the fate of toxic bait in the marine environment is so important. We have commissioned the Cawthron Institute to conduct that research, and those trials are currently being designed—they'll likely begin later this year. 

Another key consideration is that we're targeting possums and rats with this operation as a vector for secondary poisoning of feral cats. Feral cats have very large home ranges and are likely to encounter the toxin even if there are some gaps in the coverage, as they move between treated and untreated areas. 

DOC and ZIP have partnered to deliver this proposed operation, which is an urgent stand-alone measure to prevent an extinction event. However, ZIP is also responsible for developing and implementing the eradication approach for Predator Free Rakiura. This proposed operation presents an opportunity to gain critical insights into predator behaviour and control methods on the island.  

ZIP intends to conduct a small-scale eradication trial alongside the proposed pukunui operation that will help us to learn about the effectiveness of aerially applied 1080 to eradicate the three rat species on Rakiura, before the next step towards eradication gets under way. ZIP has had success with aerially applied 1080 as an elimination tool for ship rats, but its effectiveness for kiore and Norway rats is less studied. 

The proposed suppression operation is a stand-alone predator control operation, aimed at reducing populations of possums, rats, and feral cats. We are at the point with pukunui where we must take drastic action to stop their decline, to prevent an extinction.  

We will conduct monitoring before and after the operation to assess how successful it has been in reducing the target predators. Alongside this, ongoing monitoring of pukunui and other native species will serve as indicators of success. 

The Pukunui Recovery Project is aiming to rebuild the pukunui population to at least 300 birds by 2035. Ground-based predator control operations will continue throughout and after the proposed suppression operation in support of this aim.  

The pukunui flock count in April 2026 will be the next key indicator of the success of the 2025 breeding season. This flock count will inform future decisions about how we can best protect the population through predator control techniques, including any proposals for further aerial operations. 

Predator Free Rakiura plans to eradicate feral cats, possums, rats and hedgehogs from the island once and for all. The project is planning to deliver a larger-scale eradication trial at the southern end of Rakiura from autumn 2026. This next eradication trial will be shaped by knowledge gained through the proposed suppression operation to protect pukunui in 2025, and will in turn shape the following operational steps towards eradication. 

Each helicopter will cover different lines in a designated area, but the pilots will coordinate and assist each other to ensure coverage is completed efficiently.

Helicopters ideally operate between 100 and 200 metres above the ground. This is intended to ensure helicopter pilots can safely operate in mountainous and uneven terrain, and to enable the bait to fall in a way that optimises its distribution within the treatment area in keeping with their calibration. 

This is still a proposal, and it won't proceed unless the necessary permissions are granted. Community input on this proposal, and any mitigations that are added to the operational design in response, will be considered as part of the permission application.  

In May we expect to have a confirmed plan in place (subject to permission being granted). In the meantime, consultation with interested parties is ongoing and the details of the plan may change based on the feedback that we receive.  

We appreciate that people prefer to be consulted with in many different ways, and that a public meeting like this is one forum that works for some people, but may not work for everyone. We have tried to address this by providing a range of other opportunities for you to reach out to us and share your thoughts. For example, we've held drop-in sessions, and provided opportunities to approach us via email (pukunui@doc.govt.nz), or one-on-one catch-ups. We encourage anyone here to please continue to connect with us. 

ZIP hasn’t tried to eliminate Norway or kiore rats before, and that’s one of the key differences. We need to understand how effective 1080 is with these particular species of rats.

This is an area that hasn’t been as well studied as it has with ship rats. We are aware that some field studies have been conducted in the past, for example an eradication campaign on the Noises Islands using 1080 for Norway rats, delivered in a meat-based bait.  

• Moors, P. J. 1985. Eradication campaigns against Rattus norvegicus on the Noises Islands, New Zealand, using brodifacoum and 1080. International Council for Bird Preservation Technical Publication 3: 143-155. 

ZIP has launched a research program in the laboratory to better understand the impact of 1080 on wild Norway and kiore rats. Currently all  LD50 data for 1080 is based on laboratory rats, rather than wild-caught Norway or kiore rats, so we are seeking to fill this information gap. LD50 refers to the dose of a substance which is lethal to 50% of the population. This is a standard measure of toxicity. 

Brodifacoum has been used to control Norway rats around dotterel habitat in the past because rats were consuming 1080 fish meal baits intended for feral cats before the cats could get to them. Brodifacoum was introduced to stop rats from interfering with the 1080 bait, to achieve the desired knock-down of feral cats. 

1080 has been tested in various environments, including freshwater. For example, freshwater crayfish (koura) fed 1080 show traces of the toxin in their tissues, but it leaves their system quickly without causing harm. We’ve also tested it on eels (tuna), which showed similar results. 1080 breaks down more slowly in still water than in flowing water, but it does eventually break down.

Most research has focused on flowing water, and there is less research on boggy environments. But we do have a lot of information about 1080’s effect on critters in the freshwater environment.     

For instance, koura, the freshwater crayfish, were fed 1080 baits in a still water environment. They did eat some bait and it was detected in their muscle tissue, but it left their systems very quickly, in a matter of days, and it had no detrimental effect. The same has been done with eels. Possums that have died from 1080 have been fed to eels. And again, it's been detected in their muscle tissue. But it leaves their system within a matter of days and has no impact.     

In a flowing environment, the 1080 starts leaving the bait within a matter of hours. In boggy environments it will be a bit slower, but it will break down.    

Note: 1080 is highly water soluble, and baits are quickly rendered non-toxic when exposed to water through a combination of dilution and water flow. Microorganisms then break the diluted toxin down to below detectable levels. 

There are probably few toxins used in the country that have been more thoroughly researched than 1080. We've been using this toxin for over 50 years in New Zealand, and we do use more of it in New Zealand than other countries just because it's ideally suited to New Zealand conditions.

This is rare but can happen, especially after storm events. In most cases, the carcasses break down quickly. On rare occasions, they may wash up on beaches and pose a risk, for example to dogs, through secondary poisoning.  

Note: In addition to the information provided on the night, we’d like to add the following: 

1080-poisoned carcasses do contain residual toxin for a time as they degrade. Our toxic rodent trials have shown an 80% reduction in residual toxicity in a rat carcass within 14 days of death. The poison’s persistence in carcasses is long enough to pose a hazard to scavenging animals on land, which is why we can use secondary poisoning to target feral cats. 1080 is rapidly diluted and biodegraded once it enters water. 

From the research, the risk of commercially valuable fish like blue cod finding, consuming, and retaining harmful levels of 1080 from a poisoned carcass that drifts into the ocean is extremely low.  

Fish, invertebrates, and water quality have remained essentially unaffected even in areas with extensive 1080 use. There is no recorded case of 1080 contamination in commercially harvested seafood, and all available evidence suggests the risk is negligible. 

ZIP is planning trials to research the degradation of 1080 bait in marine environments. Previous studies have primarily focused on freshwater systems, so this will help fill a gap in our understanding. 

Absolutely, yes, there is scope to adjust the boundaries. This stage of the process is consultation on effects, which we acknowledge can be hard to do in a forum like this. But we do want to hear about any concerns about specific aspects of the proposed operation, and we encourage you to bring these concerns to us directly; if we can do something, we will. 

In terms of specific concerns regarding the marine environment, wild catch and marine farming representatives have been open about wanting to have their constituents bring those concerns to them so that they can share them with us in a digestible format, on behalf of the group. We certainly encourage you to reach out to those agencies if you do have those kinds of concerns, because those discussions are still ongoing. 

• Cra8 is representing the collective interests of wild catch industries (crayfish, blue cod, paua): ceo@cra8.org.nz

• The Southland Marine Farmers Association is being represented by Ali Undorf-Lay: aundorf-lay@sanford.co.nz

The main risk to native birds on Rakiura is predation pressure from rats and possums eating the adults and the chicks. It's not from 1080 operations. If you take those predators out of the system, bird populations increase significantly. And there's a lot of evidence from around the country to support that.  

It is an acknowledged fact that there is individual bird risk when it comes to bycatch and consumption of 1080, and that this risk needs to be managed and mitigated. But at a population level, the evidence shows that native birds do exceptionally well when predators are controlled. 

Note: For more information on 1080 and native birds, see Dr Graeme Elliott’s recent presentation in Oban here.

Our target is to carry out monitoring six weeks either side of the operation. That timing sometimes stretches out for logistical reasons, for example adverse weather conditions. Once we complete pre-operational monitoring, we then need to wait for the correct weather window to apply bait, which doesn’t always align perfectly. And then we plan to do the post control monitoring within six weeks of the treatment.    

We could potentially do sampling of streams on Rakiura, and we’d be happy to look into this further.  

That said, over 4,000 water samples from 1080 operations have been monitored over the years, and there have been no instances where 1080 has contaminated public drinking water. About 99.8% of the samples have shown no detectable levels of 1080. There’s been a lot of monitoring of stream invertebrates, fish, koura, and eels, and 1080 has had no negative impact on those species. All of this information is available on the Department of Conservation website, along with references to the studies. 

Note: More information is available here:  

DOC – Reviews and Regulation of 1080 

1080 and water   

• Booth LH, Ogilvie SC, Wright GR, Eason CT. 1999. Degradation of sodium monofluoroacetate (1080) and fluorocitrate in water. Bulletin of Environmental Contamination and Toxicology. 62:34–39.  

• Suren AM. 2006. Quantifying contamination of streams by 1080 baits, and their fate in water. New Zealand Journal of Marine and Freshwater Research. 40(1):159–167.  

1080 and aquatic life   

• Ministry for Primary Industries. 2016. Evaluation of Fish and Game food chain exposure pathway for human consumption of trout from within a 1080 treatment area. [place unknown]: Ministry for Primary Industries.  

• Suren A, Bonnett ML. 2006. Consumption of baits containing sodium fluoroacetate (1080) by the New Zealand freshwater crayfish (Paranephrops planifrons). New Zealand Journal of Marine and Freshwater Research. 40(1):169–178.  

• Suren AM, Lambert P. 2006. Do toxic baits containing sodium fluroacetate [sic] (1080) affect fish and invertebrate communities when they fall into streams? New Zealand Journal of Marine and Freshwater Research. 40(4):531–546. 

No, DOC hasn’t translocated them. They are only found in specific areas, such as Rakiura mountaintops and shores like Mason Bay and Awarua wetlands.

This year’s count is still under way, but we’ve already received information from the teams out there that the numbers are very unlikely to have gone up, and in fact we’re probably facing another decline. So yes; we are proceeding with planning the proposed operation.

At the moment, there is no control proposed for Mount Anglem, but there is at Rocky Mountain. We do have pest control ongoing at Rocky Mountain. Things could change, as we have a Technical Advisory Group constantly advising us on the best way to target feral cats. Should this operation go ahead, we may then be able to look at other key sites for dotterel nesting and protect those as well. 

The proposed suppression operation has the potential to play a major role in stopping the decline of pukunui, but it shouldn’t be viewed in isolation. We would also have a range of ground-based tools and techniques; for example, the intensive detection network Colin described, along with the existing trap network managed by the Pukunui Recovery Team. There are also significant developments in tools to control feral cats being developed by ZIP, DOC and others.  

Over the last 10 years, the pukunui population has experienced periods of growth and decline, and we have matched whatever resource we could afford to support the population. In recent years, we've massively increased our staff, and our trapping efforts.  

We're working as hard as we can within our limits, and obviously, we wish we could have done much more. It is not easy to be in this situation, and we acknowledge that it is not easy for the community.  

We don't think so. But the situation is getting really, really desperate; so much so that we're considering this proposed aerial 1080 operation as a stop-gap measure between now and the time that we will hopefully have a predator-free Rakiura to give these poor birds a chance.

This is a tough question. The population is declining fast, and there may now be fewer than 100 birds remaining. How many are we going to lose this breeding season if we don't act? We don’t have the luxury of time; we need to throw everything at this.    

In 2011, DOC opted to defer an operation in the Dart Valley during a mast season, after experiencing community pushback. What followed was the single largest decline of mohua on record. It took over ten years to recover the population to what it had been pre-2011. Mohua came very close to a local extinction.  

It's really hard to have foresight in this space. But at times you just have to make a call, and that's where we are at now with pukunui.

There’s no restriction of access after the operation. You can walk through it immediately after the operation. Signs will be put up, warning people (1) not to touch the bait, (2) to watch children at all times, and (3) not to eat animals from the treatment area, or within a 2 km buffer zone. 

Any recognised water supplies within the area will have appropriate mitigation in place, such as alternative water supplies. 

There is no real risk of dust traveling far from the load site. The primary concern is on the load side, but we’ve mitigated that with personal protective equipment for workers. 

Note: The research into short-to-long term health risks associated with either significant or minimal 1080 exposure is well documented. The majority of this risk assessment focuses on people preparing or using the toxins, as they are exposed to the highest concentration forms of the toxin more regularly, primarily in the form of dust/residue. Exposure at these levels has not been found to have any impact on human health. 

A 2002 study investigated just how much dust might be in the environment after three 1080 operations. The researchers detected very low levels of 1080 outside the treatment area, indicating relatively little dust drift had occurred, and well below levels that would pose a potential risk to human safety either through acute or chronic exposure. 

Te Whatu Ora – Ministry of Health has stringent safety regulations around aerial 1080 operations, including from the risk of dust associated with the operation. 

For more information, see: 

R. G. Wright, L. H. Booth, G. A. Morriss, M. D. Potts, L. Brown & C. T. Eason (2002) Assessing potential environmental contamination from compound 1080 (sodium monofluoroacetate) in bait dust during possum control operations, New Zealand Journal of Agricultural Research, 45:1, 57-65 

We’ve been meeting with fisheries and aquaculture groups as well as experienced hunters. We’re proposing to use deer repellent bait in bookable hunting blocks to address concerns.  

Note: In addition to this response, we’d like to provide the following information: 

Hunting 

• We’ll communicate directly with hunters who have bookings in any of the affected hunting blocks to manage any effects on hunting activities. 

• We’re actively engaging with representatives from the NZ Deerstalkers Association, Game Animal Council, local White-tail Management Group and experienced hunters to understand the concerns of the hunting community and explore options to mitigate them.  

• In response to requests from experienced hunters, we have started a trial to understand how effective deer repellent is for reducing the impact of 1080 on white-tailed deer. 

• For this operation, ZIP has proposed the use of deer repellent in the places where the operational area overlaps with recreational hunting areas. As with other elements of the plan, this will remain a proposal until the required permissions have been granted.   

• Using deer repellent would allow us to monitor both the efficacy of repellent on reducing impact on whitetail deer populations and to measure the efficacy of repellent bait on rats and possums. 

• We’re working with Manaaki Whenua-Landcare Research, who have extensive experience in deer research, to design the repellent trial and monitoring plan.  

• These and other trials, along with ongoing discussions with the community, will help guide the design of future eradication operations 

Fisheries and aquaculture 

• ​We recognise the importance of protecting vital local industries, which is why we’re working closely with nominated representatives from wild-catch and marine farming industries to design operations that mitigate their concerns. 

• In response to requests from these industries, no toxic bait will be sown into the sea during this operation. ​ 

• Rather than using a coastal buffer or ‘set-back’, we’ll implement a ‘safe line’ approach to minimise the risk of bait entering coastal waters.​ 

• We will not use aerial brodifacoum in this operation. 

• We’re continuing to work with fishing and marine farming representatives to respond to their concerns. Collaborative discussion and research over the next year will continue to inform the design of future operations.​​ 

• As mentioned at a previous meeting, ZIP has experience working alongside food production industries through predator elimination operations. For example, we’ve worked closely with the dairy industry and Westland Milk Products on the West Coast.​ 

The use of deer repellent is not a cost-saving exercise. In fact, it adds costs to aerial delivery, as bait with deer repellent is more expensive than standard bait. This is an exercise to try and address some of the concerns that have been raised by the hunting community.  

It is part of a package of research around deer repellents that ZIP and others are undertaking to understand the efficacy of deer repellent bait at deterring white-tail deer from interacting and consuming bait. Alongside this, we're also conducting research in the laboratory environment to try and understand how efficacious those deer repellent bait types are at targeting rats, particularly with kiore and Norway rats, which are slightly under-studied compared with ship rats.   

There are no plans to target deer as part of Predator Free Rakiura.

When ZIP began designing the non-toxic deer repellent bait uptake trials, we considered running initial tests of the repellent effect on farmed herds. However, we were advised by hunting experts that hunger will potentially impact on a deer's willingness to interact with bait. They made the recommendation not to bother testing the repellent on farmed herds, and instead to trial it on deer here on Rakiura, in their natural environment. 

Additional note: Deer repellent, in various forms, has had variable results when used in aerial 1080 operations around Aotearoa on deer species such as red and sika deer. Where operations have a high impact on deer, the availability of natural food and the hunger state of the herds has been posed as a reason.  

It is not well known how white-tailed deer will respond to deer repellent bait. It is for this reason that we are undertaking the initial non-toxic deer repellent bait uptake trials near Oban, and proposing to monitor deer through the proposed pukunui aerial operation.   

Feral cats in southern areas tend to be bigger than those further north. While we don’t have detailed information on their jaw structure or other specific traits, there is a noticeable difference in size. Additionally, feral cats are almost always either black or tabby in coloration. We are continuing to gather data on the island’s feral cats, and this may inform our approach to targeting them in the future. 

The toxin previously used in bait stations is brodifacoum, which is an anticoagulant. This toxin doesn’t cause immediate symptoms, so the idea is that cats and other predators don’t necessarily associate a bad experience with eating poisoned rats because it affects them over a prolonged period. 

And we know that secondary poisoning with 1080 is an effective method for targeting feral cats here on Rakiura. A previous ground-based operation using bait bags successfully removed 10 out of 10 cats. 

So we have evidence to suggest that feral cats do consume toxic rats on this island, and that secondary poisoning with 1080 is a potential way of targeting them. That gives us confidence going forward with this suppression operation. 

Note: This question was part of a wider discussion that took place during the hui, and wasn’t fully answered on the night. We would like to provide the following information: 

The proposed operation to protect pukunui is a suppression operation, rather than an eradication operation. Rats typically rebound much faster than cats following a suppression operation, because they are much faster to breed, so prey-switching is unlikely to be an issue in this context. 

In the context of eradication or elimination, the goal is to completely remove both feral cats and rats at the same time, which again would be expected to mitigate that risk. 

No. The cereal bait is consumed by the rats and possums, and then the feral cats consume the rats and possums. The bait itself isn’t palatable to an apex predator, so it works through a vector process.