Picturing what a predator free Rakiura/Stewart Island could look like may be as simple as casting your gaze to some of its neighbours in the Tītī/Muttonbird Island chain, where local whanau have played a huge part in providing successful biosecurity protection.
Now around 84% predator free, the eradication of predators from the Tītī Islands began 1997 with DOC funding the eradication of kiore on Putauhinu Island, a former Crown Tītī Island. In 2006 another five Titi islands were eradicated of Norway and Ship rats, in the south-western chain.
Ironically, the funding was the result of an ecological disaster, says chair of the Rakiura Tītī Islands Administering Body Tane Davis.
“Tītī settle around the coast of California before flying to us for three months to feed. Unfortunately, in 1998, the oil tanker Command was leaking as it sailed right through the tītī migration area off this coast, and around 30 thousand birds were lost in the oil slick.
“One of the dead birds they recovered had been banded on Whenua Hou, as part of the tītī research we have hosted for 14 years, and this led to us being advised to seek compensation for the loss of those birds, which we did. We used that money to eradicate rats on five of our Tītī Islands.”
However, Tane says it’s one thing to achieve a successful eradication, but quite a different thing to keep the pests away, so a biosecurity solution had to be found and put in place.
“Having the support from the people to do it, and their participation, is a huge part of being successful with biosecurity.”
“So, it was about bringing the Tītī Island whanau onboard first, and then going to the various operators like the skippers of the boats, the helicopter companies, and so forth.”
Enter Rakiura local Sandy King and her rodent detection dogs Gadget and Mawson, who now play an essential part in the islands’ biosecurity protection by ensuring all gear is checked for rodents before it gets on the vessels destined for the Tītī Islands.
“Sandy already knew a lot of the local skippers, because she comes from Rakiura, but when we first kicked off this whole biosecurity process, it was important to introduce Sandy to the skippers and the whanau she didn’t know as there was a wee bit of apprehension to begin with, which we accepted as a normal part of the process.
“Now that Sandy has built up such a good rapport with the whanau and skippers, it’s just an everyday practice.”
In addition to the tītī season, throughout the year Sandy and her dogs will jump on a helicopter and go through the islands to help whanau check the intensive trap networks around the islands and make sure they remain pest-free.
“We’re really lucky to have Sandy. It’s her initiative and she just manages it perfectly,” says Tane.
In the five years it’s been running, the Tītī Islands Biosecurity Project has been a finalist in the 2019 Te Puni Kokiri Biosecurity Awards and expanded with the addition of Karen Andrew and her rodent detecting dog in 2021.
The funding for the project is provided by Te Rūnanga o Ngāi Tahu and Kiwibank, which sponsors the Department of Conservation’s ‘Conservation Dogs Programme’.
Tane says they’d love to get to 100% predator free for all of the Tītī/Muttonbird Islands, but around 30% are on the east side and within swimming distance of Rakiura.
“Until Rakiura is eradicated these islands will continue to get the odd incursions, but this is still nothing compared to the former extreme of rats establishing themselves back on the islands and breeding again.”
Tane says the project has proven to be very successful and is an integral part of keeping the Tītī islands pest free.
“A classic example that it’s working is the fact that in 2020, when we had the first wave of COVID-19 and there was a delay in going out to the islands, some of the gear was put in storage in Bluff where it sat for about a month.
“When we got the go-ahead to go to the islands, and some of the gear was brought out of storage, Gadget found a mouse in one of the pieces of building materials. That raised awareness that it is always good to check out the gear before it goes on the boats.
“The skippers’ support is a fundamental part of maintaining biosecurity – plus, they don’t want rats and mice on their boats either.”
Thanks to the successful eradication of most of the islands, native species are now being reintroduced.
“That’s the gift to the whanau: we give them back native taonga, which in turn gives them the incentive to maintain these islands to be pest free. This project has gained so much momentum because our whanau feel that they are participating as kaitiaki, and they are taking responsibility.”
On top of all the lessons learned over the years, Tane says the project team are beginning to also test the gear they use.
“We are looking at a whole range of things in regard to biosecurity, not just checks at the wharf and on the boats. It’s also about the equipment that people are packing their gear in and how they pack it. It’s about learning new things all the time. And our people, Rakiura Māori and their whanau, are making suggestions about what to try too, which is fantastic.”
The Tītī Islands Biosecurity Project has proven that permanent eradication can be achievable, and Tane believes once Rakiura becomes predator free the same outcome will happen.
“It will take a wee while, there will be a bit of hesitation about biosecurity for Rakiura, about what those processes and policies in place will be, but it’s just about adapting.”