We won’t get to Pest-Free by trapping alone

Written by: Vanessa Mander. Published: 6 September 2022
A look into the tools we are planning to use and why each step is important.

We talk about “Tools in the Toolbox” when we consider what we need to do to get Te Pātaka o Rākaihautū/Banks Peninsula pest free. The term is important because it will take more than one tool (like trapping) for us to reach this goal. That’s just the facts. However, using a range of tools, like trapping, coupled with toxin control, followed by conservation dogs or other tools, we increase our chances of really making inroads into saving our biodiversity, and increasing economic gains for Banks Peninsula.

Joseph Langer Reserve is one place where we have been using a non-trapping tool. During July and August 2022, our team have been using PestOff! bait (brodifacoum), a toxin-based control tool for possum control. Each bait station is set up to ensure they are attractive to possums to increase the chances of them using them, while ensuring their placement is away from non-target species like pets and stock. This was a great opportunity for our team to hone and refresh their skills before we start the main Wildside pest free push.

Another tool we are looking to use is Feratox. This is an encapsulated pellets of potassium cyanide, designed for the massive bite strength of the possum. We plan to use this in our operation to knock down the dominant possums first, who exclude other possums from accessing the bait by claiming stations their own. By removing these often-larger (bossy female) possums, it allows almost all other possums better opportunity of accessing and consuming the Pest Off! bait.

So why don’t we just use the Feratox for all possums if it is that effective at knocking them down? It’s all about risk and reward. While Feratox is very quick at dispatching possums and in one dose, it also is one of the toxins with some very specific requirements for use and no immediate antidote. This then requires very careful placement of bait stations and significant effort from the team to ensure the safety of surrounding areas are safe from things we are actively not targeting, like stock and pets, accessing it. Whereas Pest Off! can require the possum to take a couple of feeds to be effectively euthanised but does have a ready antidote (vitamin K) which will be stocked by the local veterinarians. We will certainly be contacting vets in and around out site so they know what we’re doing. The risks of using Pest Off! are lessened and will allow greater coverage in areas where Feratox is too challenging to be used.

So why use Feratox (or any cyanide-based product) at all? It’s extremely effective at knocking back possums very quickly and allowing other possums to access bait stations that would have otherwise been chased off. If we miss this step, then there is a chance that we may dispatch a fair number of possums, but not enough to get to our pest-free goal and there will likely be too many for the conservation dogs to be effective – in which case we may fail and have to start all over again. To be clear, all toxin-based operations will have the clear understanding and permission of all landowners of land we will work on. This part is paramount to our success as a team and as a community.

In an elimination programme, we do not have the luxury of “just making a dent” in the population. We must strive to allow all pests in our target area equal opportunity to access bait, or be caught in traps, or be found by conservation dogs. This is why we use some tools just enough to allow another tool to be more effective at slashing those populations down to zero.

Does that mean that we are only using bait stations in these operational areas? Absolutely not. We use bait stations where trapping is less likely to knock possum numbers down in sufficient numbers or where the terrain makes trapping, too labour intensive (also too expensive). This will be followed up later on with conservation dogs to sniff out the stragglers. Trapping is still an essential element of the plan for possums and for our other species we are looking to target (like mustelids and feral cats).

Baits and toxins are ideal to use in some of our gnarly areas as long as they are used:

• In accordance with best practice, AND
• In consultation and permission of landowners, AND
• Always with the health and safety of the community in mind.

Our team are professional and well trained. We are happy to provide landowners with more information on our use of Pest Off! and Feratox.
Click here to learn more about our tools. Or, if you prefer a more in-depth discussion, please don’t hesitate to contact our team.

At the same time as our toxin operation, Manaaki Whenua Landcare Research aimed to study rat behavior, during and post bait station operations to try and improve their understanding of why some individual rats survive population control operations. They helped us refill our stations and put cameras out to monitor the bait-take. Their data will be extremely valuable in considering future rat control efforts in projects all over the country.

Doing this smaller-scale operation in Josef Langer first served multiple purposes. It was an excellent training ground for the staff, who perfected the process of safely and efficiently installing/servicing bait stations. This operation also gave us vital logistical information about how regularly we would need to refill these stations in our main operation. We concluded if we used feratox sparingly, near these bait station sites we could more quickly remove bait-guarding individuals and take the bossy dominant possums out of the picture early, allowing more animals to access bait in a shorter time frame. This way we can maximize the knockdown potential of brodifacoum. More can be found about our tool use HERE.