A trip to Glenorchy for Possum Spitfire Field Trials

May 3, 2023 1:51 pm

A blog by PF2050 Limited Project Support Manager Joan Lah

The Rees River has been in famous action movies like Mission Impossible and Lord of The Rings for its dramatic backdrop of snow-covered mountains, beech forests and braided river. I didn’t quite get to star in a Mission Impossible film this trip but I got to be part of the action in tracking dangerous possums.

Landscape photo of the Rees Valley

Envico Technologies is the brains behind further development of the Possum Spitfire concept and making it commercially viable. Through years of development, lab trials and NAWAC testing, the Possum Spitfire is in final modification stages before it goes on the market. This field trial was all about testing the longevity of the Spitfire in Glenorchy which is a 45-minute drive from Queenstown. They were installed in March and will take the ultimate test, withstanding extreme weather conditions until June. The Spitfire has high interactions, efficacy, economical value and low risk to non-targets species. It delivers up to 80 lethal doses and can be left in the field unattended up to one year. The device has adjustable parameters like operating time at night, minimum and maximum weight limits, and how much lure is dispensed. The possum will stand on the weight sensor and as it reaches up to have a nibble of the long-lasting mayo lure, it will trigger the height sensor. If it reaches or exceeds the threshold of the weight and height, the device will spray a delicious toxin on its belly. It is so tasty that during grooming, the possum will ingest the toxin and will never be seen again!
Arkady Edmunds installing Possum Spitfire from his phone
The device can be easily set up through the user-friendly phone app that Envico Technologies also created. It connects to the device via Bluetooth and can be set up with or without reception. My personal favorite add-on to this product is that if you’re within range of the device but can’t quite find it, you can get it to beep which makes it easier to find. If you’re from a field background, you’ll understand that not visiting a site for a year means that you may not remember where the devices are, so this is a great addition! The weight limits can be changed depending on what species are in the area. There are plenty of curious keas in the area, so to be safe we set the minimum weight threshold to 1.4kg, anything less will not trigger the toxin. Whenever the sensor is triggered, the Spitfire will record and save the data. It tells us the time and date it was triggered, the weight of the possum, all you need to do to retrieve that data is connect your phone!
Joan Lah hammering a sign to a tree while Arkady Edmunds mounts a Possum Spitfire to the tree.
We woke up to a bright frosty day where we started with a toolbox and split into two teams of five to ready ourselves for facing the beech forests! We stocked up on nails, hammers, signs, flagging tape, cameras and of course, Spitfires. The teams drove along the river on an unpaved road and arrived at the site. We split the sites in half and each team was on their merry way. Trudging along in the beech forest, I couldn’t believe how lightweight these devices were to carry, making it easy to pack a few in a tramping pack and bush-bash up and down hills. The navigator held the GPS and we lined up like ducklings, following behind avoiding bluffs and sudden cliffs to find a good spot for the Spitfire. When we found a good thick tree, we got down to business and started hammering, installing, and flagging. The Rees Valley was an ideal location for these field trials as there has never been possum control in this area. The local miromiro, tātaruwai and korimako needed the help of the Spitfire to say the least!

 Bec Simpson and Chrissy Becker-Fifield carrying Spitfires to site.

The whole day was fun and educational. All thirty devices were successfully deployed along the Rees with high spirits, good banter and a bit of Taylor Swift here and there (not by me of course). Boffa Miskell organised the field trials and the Southern Lake Sanctuary and Routeburn Dart Wildlife trust were there to guide us through their backyard. Both groups were passionate about conservation and protecting the unique fauna in Aotearoa. The Possum Spitfire is a game-changing device for conservation, I am so excited to see this device used all over Aotearoa and watch our native fauna flourish again.


I would like to acknowledge Phil Elton and Arkady Edmunds from Envico Technologies for their hard work on the Possum Spitfire and dedication during this field trial.

Thank you to Brent Barrett and Bec Simpson from Boffa Miskell for leading and organising the operational plan to deploy the Spitfires. Because of Brent we had a successful field trial and Bec was a massive help in organising equipment and food.

Thanks to the Routeburn Dart Wildlife Trust, Chrissy Becker- Fifield, Ole Schramme, Clodagh Byars, for doing pre-monitoring and for checking these devices every week for the next 4months.

Thanks to the Southern Lake Sanctuary team, Bonnie Wilkins, and Greg Whall for their hospitality and showing us the ins and outs of their sites! It is clear they are dedicated and passionate about conservation.

Thanks to Nick Zaloumis from Trap and Trigger for making the trip down and sharing his knowledge during this field trial.