Frequently Asked Questions
Why is the Tū Mai Taonga project needed?
How can I support Tū Mai Taonga?
How can I be a responsible cat owner?
Why is the Tū Mai Taonga project needed?
Unfortunately, current efforts to manage feral cats and rats on Aotea is not enough to protect our most vulnerable species.
In 1994 the last two male kōkako on Aotea were removed to Hautūru, Little Barrier Island with he hope that their offspring may one-day return.
Other species lost to the island since European settlement include the tūturuatu (shore plover), hihi (stitchbird), tīeke (saddleback), koitareke (marsh crake), popokatea (whitehead), pipipi (brown creeper), tītipounamu (rifleman), yellow-crowned kākāriki, tītī (sooty shearwater), kuaka (common diving petrel),tuatara, pekapeka (short-tailed bat) and pūpūharakeke (giant land snails).
Although Aotea is free of possums, mustelids and Norway rats, some species are only just hanging on despite widespread efforts to trap ship rats, kiore and feral cats - like the oi (grey-faced petrels) which are still scattered around cliffs, the reintroduced toutouwai (North Island robins), and rare miromiro (tomtit), the vagrant korimako (bellbird), red-crowned kākāriki, matuku (bittern, mātātā (fernbird), mioweka (banded rail), pāteke (brown teal), tītī (Cook’s petrel), tūturiwhatu (New Zealand dotterel) tākoketai (black petrel), pepeketua (Hochstetter’s frog), Duvaucel’s gecko, moko kākāriki (Auckland green gecko) and the niho taniwha (chevron skink).
The good news is that the benefits of sustained predator control is being seen in island sanctuaries at Windy Hill (where more than 60,000 rats and nearly 400 feral cats have been removed over 23 years), Glenfern and Motu Kaikoura. Bird counts at Windy Hill show increasing abundance of kererū, tūī and kākā.
Tū Mai Taonga is an opportunity to build on these success stories, initially the Aotea Conservation Park and north of Aotea. Once techniques and methodologies are proven and the community is ready, the project will look to extend operations across the whole of Aotea.
Why are feral cats a problem?
Feral cats are expert hunters and have a diverse diet often heavily focussed on native species. This is because our native species evolved in the absence of predators like feral cats and so have few natural defences. Feral cats eat adult birds, chicks, eggs, geckos and skinks. In Aotearoa, feral cats have contributed to the extinction of 9 native bird species and impact on 33 now endangered species.
They are quite different animals from the average domestic cat, which maintains a small core area of home range, often as exclusive property. Feral cats on the other hand, have much larger home ranges which may overlap with those of other cats. Range size can be anywhere from 48 to 700 hectares, but even up to 2000ha on Rakiura/Stewart Island. It all depends on habitat, food availability and, for males, where females are.
Feral cats, particularly kittens, have a shorter life span than domestic cats. House cats commonly live for 15+ years whereas feral cats may only live for about 6 years. It's a hard life in the wild, despite the presence of easy food. Most kittens are born between spring and summer which is often when we see them on Aotea.
Because they range widely and need a lot of energy to survive in the wild, feral cats can do significant damage. Like most predators, they are tuned into 'easy wins' in their environment such as where colonies or gatherings of their prey species are. On Aotea this includes tākoketai, black petrels on Hirakimatā, pāteke at Okiwi and elsewhere, oi (grey-faced petrels) on the coast, and tūturiwhatu, dotterel at Whangapoua. Kākā and kākāriki chicks fledge out of nests and onto the ground and are also very vulnerable to cats when young.
While feral cats are known to eat rats, rat breeding rates and densities are so high in the Aotea bush that feral cats are unlikely to have any more than a limited effect on overall rat numbers.
Why are rats a problem?
Rats are far more numerous than feral cats because they are so well adapted to our conditions. Rats have a short lifespan (about 17 months) and are fast breeders (every 6 to 8 weeks in summer and autumn). They can breed more quickly when there is more food, and in ideal conditions rats can produce up to 10 offspring at a time. In temperate northern environments like Aotea, rats may breed all year round, where there is abundant food and shelter.
There are two rat species on Aotea: kiore, the Pacific or Polynesian rat (Rattus exulans) which arrived with Polynesian voyagers, and the more damaging ship rat, or black rat (Rattus rattus) which arrived in the mid-1800s. These invasive rats pose a greater threat to island wildlife than any other at the present time.
Ship rats are found from the coast to the treeline and spend a lot of time in trees, so as well as damaging your orchard and crops, wiring and buildings they can strip forest trees of berries and nests of chicks and eggs.
Kiore numbers are often influenced by where ship rats are not. Ship rats are their competitors and can keep kiore numbers down. Therefore it's important to control both species at the same time.
Rats are damaging because they reduce bird numbers directly by eating both chicks and eggs, herpetofauna (frogs, geckos and lizards) and invertebrates.
Rats also compete with birds for food and damage the forest by eating seeds and seedlings. This means there are fewer birds spreading seeds to regenerate the forest. The cumulative effect of rats doing this damage is that the forest is less able to recover and is less resilient to fire and other stressors.
What is Tū Mai Taonga’s plan?
Tū Mai Taonga’s operational plan draws on an independently authored feasibility study and is informed technical and cultural advisors.
The first stage of the project is focussed in Te Paparahi, the rugged forested north of the island, where the project is currently establishing a network of around 500 traps for feral cats across 4,500ha.
With ship rats and kiore, initial focus will be on small offshore islands and trialling new methodologies and tools that can effectively remove all animals and defend for reinvasion.
Tū Mai Taonga aims to build a skilled conservation workforce on the island.
With growing capacity and proof of concept it aims to inspire and unite community and agency effort to achieve a predator free Aotea, anchored by the tikanga of mana whenua.
Can I work for Tū Mai Taonga?
Tū Mai Taonga is recruiting for a range of junior and senior field-based roles and support work. See https://www.tumaitaonga.nz/vacancies for more details.
How can I support Tū Mai Taonga?
Tū Mai Taonga is designed to support the efforts of community groups around the island by proving methods that can eradicate feral cats and rats across large landscape areas.
The Ecology Vision website contains links to the groups you can get involved with to help the mahi.
How can I be a responsible cat owner?
Auckland Council has produced a guide to responsible cat ownership and offers free microchipping and desexing of domestic cats and an online register, the Cat-alogue.
For more information see here.