From late November through early March. a team of eager individuals from Abseil Access converge on Mokai Valley in the Taihape area to search and control white bryony (bryonia diocia).
First discovered in Mokai Valley in 1991, DOC has been actively working with MPI towards the eradication of this white bryony since 1999. The plant has been considered a priority pest for national eradication since December 2006, and is included in the National Interest Pest Responses (NIPR) programme.
Senior Ranger Biodiversity Dan Tuohy says white bryony has the potential to impact on economic, biodiversity, and landscape values.
“White bryony smothers and shades out many of New Zealand’s native and desirable introduced species,” says Dan. “It’s a climbing vine, so requires a lot of grid searching in the bush, along cliff lines, and through nearby land. Control requires a surprising amount of abseiling and physical activity
Invasive weeds destroy our native plant communities, and can make the unique natural landscapes of Aotearoa New Zealand unrecognisable. Weeds can also provide hiding places for pest animals, increasing the risk posed to our native bird species. Some common weeds include purple loosestrife, gorse, and even trees like wilding conifers.
Gorse is a real horror story and shows one of the worst-case scenarios for invasive weeds. Since its introduction in the mid-19th century, it has become one of the country’s most ubiquitous and recognisable weeds, and extremely expensive to control.
“We need to make sure white bryony doesn’t become the next gorse,” says Dan.
White bryony is known to be present in two places in New Zealand:
• Makino Reserve (Rangitikei River Valley) near Taihape. • Aria and Mokauiti near Te Kuiti.
If you have seen it or suspect you have seen it, please contact the Biosecurity New Zealand Exotic Pest and Disease Hotline on 0800 80 99 66 or online at: report.mpi.govt.nz/pest.
The type of information to have with your report is:
• Location (a GPS point would be good) • Photo • Size, how big is the plant • Defining features (is it flowering, fruiting, etc)
“Protecting New Zealand’s biodiversity is a team effort,” says Dan. “Together, we can make this invasive weed history.”
What the next 20 years of predator free islands hold.
In this two-part series, we’re celebrating 20 years of Aotearoa New Zealand’s largest predator free project to-date. Looking to the future, we explore what the next 20 years of restoring New Zealand’s wild and precious islands may hold. Learn how artificial intelligence, the history of phones, and feral pigs all connect.
Written by Janel Hull.
20 years ago, DOC declared the seemingly impossible operation to make Campbell Island predator free a resounding success.
The techniques that DOC staff on Campbell Island/Motu Ihupuku pioneered helped propel the world into exponentially scaling up eradications of bigger and bigger islands. DOC’s Predator Free 2050 Senior Manager, Brent Beaven, shares how Campbell Island changed the game. “Campbell Island helped unlock a step change in what we thought was possible.”
DOC Predator Free 2050 Senior Manager, Brent Beaven, translocating a rare native tīeke (South Island saddleback) | Photo: Peta Carey
Now, there have been over 1,000 island eradications in the world. And New Zealand is responsible for the lion’s share.
Thanks to these predator free breakthroughs, islands across the world are covered in screeching penguins, soaring albatross, and chubby sea lions. We were able to save precious native plants and animals from the brink of extinction.
But momentum in creating larger predator free islands has unfortunately waned. Brent notes, “The island eradication tools and techniques we use now have allowed us to achieve some incredible things. But, to scale up to larger and more island eradications, we need innovation.”
Technology and techniques haven’t changed much since the 2001 Campbell Island operation. Island eradications in 2023 use similar GPS, helicopters, and techniques. Which is surprising considering that in 2001 the first ipod was released, we had just survived Y2K, and fax machines and landlines reigned supreme. These predator eradication techniques are tried and true and get the job done. But the tools aren’t effective and efficient for eradicating predators from very large islands or the mainland of Aotearoa.
To tackle restoring larger islands and the mainland, we need new tools, techniques, and technology. We need investment to shift from reliable landlines to transformative smart phones.
Predator Free 2050 has focused government investment into this innovation. Since the goal was announced in 2016, programmes like DOC’s ‘Tools to Market‘ and Predator Free 2050 Ltd.’s ‘Products to Projects’ have invested in possible game changers like biodegradable aerial rat traps, AI cameras and image recognition, smart detection devices, pest-specific toxins, and research to map predator genomes to understand their unique weaknesses and biology. In just the first five years of Predator Free 2050, government has invested $43 million into tools, research, and software for predator eradication.
Biodegradable aerial rat traps | Photo: GoodnatureZero Invasive Predators (ZIP) innovation and operations team talk through a prototype | Photo: Robyn Janes
It’s unlikely research will uncover just one “silver bullet” for eradicating introduced predators. But with the help of investment and new tools and technology, Aotearoa could accelerate efforts to restoring precious islands and our mainland.
Predator Free 2050 has also helped launch DOC’s National Eradication Team (NET). This team is working on a strategy for eradicating predators from all of New Zealand’s uninhabited off-shore islands. They’re leaders in predator eradication – spearheading strategy, testing new techniques, and advising on island eradication projects both in Aotearoa and around the world.
Some members of the National Eradication Team | Photo: Finlay Cox
DOC’s eradication experts have already achieved great things for people and wildlife. In 2018, a DOC team led the charge to successfully eradicate mice from Antipodes island, protecting wildlife like wandering albatross.
They’re also sharing their knowledge and expertise abroad. In 2023, they led a rat eradication on Palmerston Atoll in the Cook Islands with our neighbours in the Pacific who were struggling with rats destroying food and threatening their community’s health.
National Eradication Team member supporting Palmerston Atoll community members with trail cameras and rat surveys | Photo: Em Oyston
With the leadership of DOC and investment in tools and techniques, Aotearoa is taking strides to accelerate island conservation.
And these experts have their eyes set on the next big island restoration – Maukahuka Auckland Island.
Maukahuka/Auckland Island is a stronghold of remarkable plants and animals. As a subantarctic nature reserve and World Heritage site, it is home to some of the world’s rarest animals like the Gibson’s albatross, southern right-whales, New Zealand sea lions and hoiho (yellow-eyed penguin).
The island supports over 500 native plants and animals with more than 100 found nowhere else in the world. The wild landscape has blushing rātā forests and windswept clusters of bright megaherbs. Maukahuka is of great cultural and spiritual significance to Ngāi Tahu, with a long history of Polynesian expeditions to the islands to gather food and settle.
Megaherb carpets on neighbouring predator free Enderby Island | Photo: James WareHoiho/yellow-eyed penguins | Photo: Rachael Sagar
Sadly, over the last 200 years, populations of feral pigs, feral cats, and mice have inflicted severe harm. Now, of the 39 native bird species that were once on the island, 28 are either gone or remain in very small numbers. Large swaths of rātā forests have disturbed soils and stunted understories. Megaherbs are dwindling. Without action, plants and animals will continue to disappear.
Feral pigs in a white-capped albatross colony on Auckland Island | Photo: Paul Sagar
At about four times the size of Campbell Island, achieving a predator free Auckland Island would be a massive undertaking. It would be New Zealand’s largest predator free island and the final step to finally restore all of New Zealand’s subantarctic islands.
In 2021, the National Eradication Team spent three years investigating whether it was possible to eradicate pigs, mice and feral cats from Auckland Island. They concluded that making Auckland Island predator free would be achievable, worthwhile, and sustainable in the long run.
But first, the project would need about $9.75 million per year over 8 years to tackle the challenge. Innovation in image processing and targeted baits has steadily reduced the time and cost. But it would still require unprecedented support and investment.
Looking to the future, New Zealand could make even bigger strides in conservation on islands like Auckland Island. Brent reflects, “All of our progress on previous islands helped build the confidence to launch Predator Free 2050. We’re now seriously eyeing up another step change in possibility with Maukahuka Auckland Island.”
Predator Free 2050 is helping tackle the challenge of innovating new tools and technology, spearheading a strategy for restoring all islands, and growing new levels of community support and investment for eradicating pests.
The next 20 years could be promising for predator free islands. But it’ll be a challenge. Brent notes, “We’ll need to innovate, test our limits and be prepared to take a bit of risk as we step into the unknown.”
Written by Vanessa Mander, DOC’s Predator Free 2050Communities Advisor.
Life as a ranger means that you are at the front line and members of the public see us as a trusted source of best practice trapping information. The green uniform appears to act like a beacon of sorts in the field. I certainly found that!
Questions I have been asked:
“How do I find out what pests I’ve got?” to “What sort of humane traps are right for possums on my lifestyle block?”, to the very real, “my chickens are getting nailed by a stoat (or some other furry sod), what lures should I use in my traps to deal to it?”
Vanessa checking a tracking tunnel | Photo: DOC
But what if you too could possess these answers, all at your fingertips?
Since 2019, we’ve been printing and revising our popular publication, the Practical Guide to Trapping. It is often referred to as a “ranger in your back pocket” because it’s full of important best-practice information to help you with your trapping work. There have been so many circumstances that this book has come to my rescue. It’s the trapping bible that people really should know about.
The DOC Predator Free Communities Team is now launching the 3rd edition of this amazing guide. Since 2019, we have distributed well over 35,000 hard copies to communities, as well as 6,000 downloads from our website.
Senior Biodiversity Ranger Archie with the 3rd edition of our trapping guide | Photo: DOC
What can we expect with this new and improved trapping guide?
The third edition builds on all the great, best practice trapping and predator species information, and now also includes:
Site specific updates on kauri disease and myrtle rust
Updated information on recording your trap catch
Updated suppliers and links
And so much more!
We are also excited to share the Predator Control Calendar and Stoat and Rat Trap Checklist in this new edition, courtesy of our friends at the Predator Free New Zealand Trust.
A DOC200 trap in the Waimakariri valley | Photo:Holly Thompson, DOC
These are used far and wide, and beloved across the motu, so don’t trust just us! Here’s what a range of people are saying about the Practical Guide to Trapping:
“The trapping guide is a highly valuable booklet for communities and contains vital information on animal ecology as well as DOC best practice trapping methodology and biodiversity monitoring.
A great resource, improved further with some of our own branded material including our popular Predator Control Calendar and our new Stoat and Rat Trap Checklist. The trapping guide has always been very popular at our Cam Speedy Roadshows across Aotearoa.”
Jessi Morgan, CE of the Predator Free New Zealand Trust.
The guide has great trapping information for community groups | Photo: DOCThe Predator Free tohu on a trap | Photo: DOC
“This little booklet is packed full of useful information. Covering animal biology, best practice monitoring and solid trapping advice, it’s never far from hand and an excellent resource for individuals and communities whatever their experience or scale.”
Tim Sjoberg, Senior Team Lead at Pest Free Banks Peninsula.
“We find the trapping guides enormously useful for our teaching & trapping. The guides are a handy size and robust. They are very easy to follow, and we find the detailed plans and dimensions of trap boxes very useful.”
“It is great to have detailed information on pests and reputable ‘best practice’ trapping options in Aotearoa in one booklet. Selecting the right trap for the right environment and for the target predator is essential for successful conservation outcomes and this guide lays out all the information and detail to get you off to the right start.”
Becs Gibson, NMIT.
“At the Visitor Centre’s in Taranaki, we find that the public really enjoy the books and they are popular!! Students who study Pest Ops [Western Institute of Technology Taranaki] must choose a target species and research it’s biology, behaviour, impacts and control methods – which the ‘bible’ serves as a great resource.”
Georgina Ngametea, Taranaki DOC Visitor Centre & Western Institute of Technology Taranaki.
Georgina with an earlier edition of the trapping guide | Photo: Western Institute of Technology TaranakiA ranger and volunteer setting a trap | Photo: DOC
Come and join in the action with us! You can pick up your own copy from your nearest Visitor Centre, or download a copy from the DOC website. But don’t worry if you already have one of the other versions, it’s still got some great best practice info in there and got some life in it yet!
Last summer Sam Fisher spent a week in one of the most beautiful places in Aotearoa. Sam chatted to us about the sacred lakes in Nelson Lakes National Park and the latest measures to keep them safe from a new, invisible threat.
Rotomairewhenua / Blue Lake, Nelson Lakes National Park | Sam Fisher, DOC
I was previously working in IT but switched to conservation. Early midlife crisis career change you ask? Something like that. I completed the ranger training programme earlier this year and was lucky enough to have my summer placement with the Nelson Lakes team.
As part of my placement, I got to be hut warden at Blue Lake Hut for a week.
On the way up to Rotomairewhenua / Blue Lake | Sam Fisher
Yeah, it’s a magic spot
Rotomairewhenua / Blue Lake is nestled amongst the 2,000m peaks of the Nelson Lakes National Park, sitting at about 1,200m above sea level. It takes 2 days to get there, a tramp that takes you through vast valleys and over high mountain passes. It’s a journey into the remote heart of the park.
Look at the photos and see how stunning it is there! Rotomairewhenua has the clearest freshwater in the world with a visibility of around 70 metres underwater. Incredible.
The pristine water of Rotomariewhenua / Blue Lake, Nelson Lakes National Park | Sam Fisher, DOC
I was super fortunate with the weather when I was up there. It’s such a beautiful backdrop and you get some amazing reflections off the lake.
The bonus of being the warden is that you get the place to yourself for a good chunk of the day (after the cleaning is done of course!), while the trampers are moving through. Standing up there on a clear day, it’s something else to see. Everything is blue – blue sky and blue lake on a bluebird day.
Sam’s obligatory tramping selfie, high above Rotomariewhenua / Blue Lake | Sam Fisher, DOC
The birds are stunning too – you’ve got rifleman hanging out all around around the lake. You can just sit back and listen to them and see if you can see them. They’re one of my favourite birds to spot because they’re always around there.
Life in the past lane
I’ve heard stories from older volunteers who spent time at Blue Lake Hut decades ago, that they used to dare each other to get in the lake because it’s so numbingly cold! Others used to use it and Rotopōhueroa / Lake Constance for washing or as a water supply.
I think people were hanging on to those memories, but today we know it’s not appropriate to do that. Times have changed, as have our practices.
We’ve wised up to respecting the culture
The lakes are now called by their original names on maps. So we have Rotomairewhenua / Blue Lake and Rotopōhueroa / Lake Constance on all the maps. This acknowledges the long history and high cultural significance that they have for Māori, particularly Ngāti Apa ki te Rā Tō iwi.
The lakes are tapu (sacred) and are not to be touched. This is to uphold their mauri (life force) and purity.
We show respect for the lakes and for the iwi by never touching the water. That means no swimming, filling drink bottles or washing clothes.
Rotopōhueroa / Lake Constance | Sam Fisher
Staying out of the water keeps these special lakes safe
The other message I tried to get across in my hut talks was about the serious threat of invasive algae getting into these lakes. Two microscopic algae – lindavia and didymo – are already present down the hill in Lakes Rotoiti, Rotoroa and Tennyson.
Lindavia produces lake snow, a really ugly snot-like slime that hangs below the surface of the water. Didymo coats rocks with a gross white material that looks like wet toilet paper. They would both really stuff up the lakes and headwaters of the rivers.
It could only take one person to wander into the lake with wet boots or togs on – even if they’d swum in Lake Rotoiti a few days ago. Or splash a drop of contaminated water from their drink bottle. That one innocent action could infect the lakes with invasive algae and spoil them forever.
Once the algae are there, there’s no way to get rid of them – no going back. It would destroy the visual and cultural significance and go against everything we’ve agreed to do in terms of protecting the environment for everyone, including Māori.
Talking to trampers and Te Araroa walkers, it seemed like the two-pronged approach to caring for the lakes – the cultural significance and the biosecurity – was well received and respected.
Alternative water available – you can cool off in the stream
Getting up to Blue Lake Hut is a big walk for sure. As a tramper I know it’s really, really nice to be able to have a refreshing dip at the end of the day.
Because you can’t swim in the lake, we’ve provided an alternative.
I made a track down to a stream where people can go. It’s just 5 minutes away and is all signposted before you get to the hut. It’s freezing cold but a great option on a hot day. The stream does turn into a pretty steep river just downstream, so we ask people to take a bit of care.
There are also those wet days when the hut is full of dripping wet gear and the fire’s going – then it’s more like a free sauna in there!
One of the beautiful rivers of the Nelson Lakes National Park | Sam Fisher
New cleaning stations
This summer we’re putting in cleaning stations near the main access points at Coldwater, Lakehead and Sabine Huts. It’s an extra step to reduce the chance of lindavia and didymo getting into our pristine rivers and alpine lakes.
As I said, those nasties have already got into the bigger, more accessible lakes – Rotoiti, Rotoroa and Tennyson. Lindavia arrived about 4 years ago so we’ve really had to tighten up our biosecurity to keep it out of the rest of the park.
The cleaning stations are pretty simple. There’s a tank with pre-made 10% detergent solution, a sink and a bucket underneath to hold the used solution. I’ve literally just finished painting them – DOC green of course!
The new cleaning stations under construction. These will help to prevent the spread of Lindavia into the alpine lakes| DOC
Everyone needs to clean all their gear that’s wet or damp from any river or lake water. So it’s stop, soak and wait for 10 minutes. This is the Check, Clean, Dry method that people have probably heard of, and yeah, it does work to kill those microscopic algae.
Most people know how important it is to use the cleaning stations in the upper North Island to protect kauri, so I think people will embrace this way of protecting our lakes too.
You just need to allow ten extra minutes to do the right thing. The cleaning stations are all near huts where people often stop to make a cuppa or have a snack anyway, so we’re anticipating that it won’t be much of a hassle.
For now and for the future
We’ve got a totally unique environment with the lakes and mountains up there. It’s got to be for everyone forever, not just for me today.
I sometimes ask people how they’d want to leave it for their kids, and their kid’s kids. I don’t have any kids (keeping well clear of that!) but do have plenty of nieces and nephews. I’d hate for them to come here and not get to see the same pristine environment I got to see.
So finally, on behalf of the team here at Nelson Lakes, we really welcome you to come and experience this amazing part of the world. And we trust that you’ll follow our simple rules to keep it that way for everyone who comes after us.
