An individual mouse is tiny, with a territory of just six to eight metres. But that tiny mouse represents a bigger problem, with a range that spreads from your house to your garden and the wider local and global environment. That’s why, if we want to make the world a wilder place, we can’t forget about the humble house mouse.

Goodnature has been on a mission to rewild the world since 2005, when we developed our first eco-friendly rat trap in a New Zealand bush section. Since then, we've trapped rats and other introduced pests worldwide – 22 million of them – giving nature a chance to do its thing without interference. Mice are the natural next step – they reduce biodiversity in gardens and surrounding areas, and the toxins and poisons used to kill them cause harm across the ecosystem.

Here's how mice are intertwined with our rewilding mission – and how the mouse in your house has a bigger environmental impact than you might think.

What is rewilding?

Rewilding isn’t our word – it’s a global movement. First defined in 1992, it’s an approach to conservation that prioritises repairing, restoring, and supporting ecosystems to return to their natural states. Where traditional conservation efforts often focus on protecting a single species or habitat in isolation, rewilding takes a whole-system view, trusting that a functional ecosystem can take care of itself and the species that live in it. In short: undo damage caused by humans, let nature lead.

Early rewilding often focused on reintroducing large predators that had been driven out or become extinct, in the hope that they would help restore those natural patterns. Now, rewilding has a much wider scope – there’s no one way to do it.

Rewilding can look like restoring damaged landscapes through replanting, removing artificial waterways, and returning agricultural land to nature. It can mean eliminating the pest animals and invasive plants that compete with native species and reduce biodiversity. It can involve minimising the use of pesticides and rodenticides, so soil and water can thrive. It can mean individuals doing their bit to create greener, wilder spaces in small urban gardens.

Goodnature Co-founder Craig Bond puts it simply: “As far as rewilding goes, at any scale it’s the same formula. Remove the things that are not supposed to be there, then allow nature to do its thing."

Why rewilding matters

We don’t need to tell you that the natural world is in trouble. Biodiversity is down, with animal and plant species being lost at an alarming rate. Pollution in the air and water, plastics and rubbish in our oceans, forests being felled to make way for food crops – and the looming threat of climate change hanging over everything.

While it's easy to feel hopeless about the state of the world, we prefer to turn our lens to the positive stuff. Our work with rewilding organisations helps – we get to see amazing work going on all over the world, so we know it can be done. One close-to-home example: Wellington City. Our home base, Wellington is one of the only places in the world where urban biodiversity is increasing rather than declining. As a result of a whole host of community-led conservation projects, big and small, the region has seen a significant resurgence of native birds in green spaces and gardens. For example, kākā were reintroduced to Zealandia (Wellington’s predator-free reserve) in 2002, and a flock of hundreds now has the run of the city. Incredibly, this has helped move the kākā’s conservation status from ‘threatened’ to ‘recovering’.

Wellingtonians have got on board in a big way, with community pest trapping programmes and Predator Free groups in suburbs across the city doing their part to eliminate pests from parks, bush, and backyards. As locals, we’re proud to be doing our bit as well – Goodnature traps are used by a good chunk of suburban trappers, and we’re involved with rewilding and conservation projects across the city.

It’s an amazing example of the power of community – and the impact of rewilding. By restoring natural spaces, however small, we can help nature get back into balance. Soil rich with nutrients, insects and microorganisms, and more native plants, birds and animals – when wild spaces work as they should, they bring a whole network of positives.

The big picture: We want to rewild the whole world, not just the parts we think of as wild or natural. Every little bit counts. It’s about fighting climate change and protecting the places, plants, and creatures that make our world unique.

How the mouse in your house makes the world a less wild place

House mice are technically wild creatures, but when their population gets out of balance, they make the world less wild in many ways. When they're not hiding in your walls and behind your fridge, mice make their way outdoors and cause real damage to the delicate ecosystem. In your garden, they eat seeds, fruit and, perhaps surprisingly, invertebrates and our native skinks and geckos. One New Zealand study found that areas without mice had twice as many beetles, wētā and spiders than areas with mice. The same goes for earthworms, which mice eat in large numbers. While it's less common in urban gardens, mice have been known to feed on birds’ eggs and even live chicks in nests.

Why does this matter? Beetles, worms and other invertebrates have crucial roles in the ecosystem, helping keep soil healthy and pollinate plants. If they’re eaten by mice, they can’t perform these roles.

Seeds and fruit matter, too. You'll have fewer grasses if mice eat all the grass seed. Mice can also climb trees and eat seeds and fruit from native species, which means less food for birds and fewer opportunities for seed dispersal. One example: the Kererū, New Zealand’s native wood pigeon, eats the fruit from native plants and trees including pūriri, nīkau, miro, and tawa, then scatter the seeds as it flies. Other places have their own seed-spreading species – they’re a key part of the biodiversity cycle.

Traps, toxins and unintended consequences

How we control mice has a tangible impact on the broader environment. Traps and toxins (also called poisons) are the most common methods for indoor mouse control, as they’re both cheap and relatively easy to manage. While some types of traps may be less than adequate or eco-friendly, they’re not directly harmful. Toxins can be a different beast.

Toxins or poisons are widely used to kill mice in residential homes and rural areas. It’s easy to see why: toxins are a simple, hands-off way to deal with a mouse problem, and they work. Buy rat or mouse bait in pellets or paste at the hardware store, set up a bait station and you might never have to see a mouse in your house again.

The trouble is, that’s not the end of the story. When you use a poison to target mice, it enters your garden’s ecosystem and you can’t control - or even see - the knock-on effects. Beetles and other invertebrates may feed on bait pellets or pastes in your house or garden, then pass these toxins on to birds and other animals that eat them. Predator species that feed on dead or dying mice can also be affected. While animals further up the food chain won’t necessarily ingest a fatal dose this way, toxins in their systems can cause organ damage and health issues.

In New Zealand, for example, the Ruru (native owl) and Kārearea (New Zealand falcon) both prey on mice and other small rodents, leaving them open to secondary poisoning. Both species are protected and vulnerable already – harm caused by toxins is literally last thing they need.

Outside Aotearoa, other places have their own precious and vulnerable native species. In Australia, native owls and tawny frogmouths are affected by rodenticides. In the UK, owls, foxes, and kites are harmed or killed through secondary poisoning. In the US, there’s an even longer list of animals at risk from rodenticides – including foxes, coyote, wolves, raccoons, bears, skunks, and badgers. The good news? In many areas, secondary poisoning has been a catalyst for positive change around toxins. For example, California has banned first- and second-generation anticoagulant poisons since 2020 in an effort to protect native foxes, bobcats, cougars, and mountain lions.

Mice, ecology and predator-free spaces

Here’s the bad news: mouse populations are on the rise worldwide. Thanks to climate change, winters are milder, which means increased survival rates for mice (and other rodents) and the prospect of a population explosion. It’s a problem in urban areas, where there are readily available food sources for mice and fewer natural predators to keep them in check. As mice reduce biodiversity in those urban spaces, predator species drop off, and the cycle continues.

In New Zealand, there’s some incredible work happening around removing pests and predators from our forests and wild spaces. Predator Free 2050, which aims to eradicate rats, stoats, and possums from Aotearoa, is one of the most ambitious. Launched in 2016, the project goes beyond the Department of Conservation - it’s about mobilising all New Zealanders to play their part in protecting biodiversity and our native species.

While there’s no straight line to success when it comes to such a complex issue, the initiative is making real progress. In its 2022-23 report, PF2050 noted that 18 large-scale pest control programmes are underway across New Zealand, covering a total of 800,000 hectares in rural and urban areas. Kiwis are getting on board in a big way as well, with 39% aware of the predator-free goal and 34% keen to get involved with trapping invasive predators. That’s the sort of grass-roots, real-world impact we like to see.

Naturally, we’re huge supporters of PF2050. In fact, our outdoor rat traps are used by local trapping groups all over New Zealand.

Mice aren’t on the hit list for PF2050, and we get it - with limited budgets and a massive job to do, it’s crucial that the project focuses on the pests doing the most damage. We’re hopeful that, as bigger predators are knocked out of our ecosystems, we’ll be able to focus on the little ones next. In the meantime, we’re doing our bit to minimise mice in urban ecosystems and - fingers crossed - getting more Kiwis engaged with the concept of toxin-free, biodiversity-friendly mouse control.

More mouse mahi (work) around the world

Despite the doom-and-gloom around climate change and declining biodiversity, there's much to be hopeful about. Our rewilding mission connects our team with incredible people and organisations worldwide, working tirelessly to restore and protect natural places.

There’s a lot of amazing mouse-focused work happening all over the world, from DOC successfully eradicating mice from New Zealand’s Antipodes Island, to The Mouse Free Marion project on a remote island in the Indian ocean, to Lord Howe Island in Australia, which is working to eliminate mice and protect native species. On a smaller scale, there are backyard trapping groups all over the world, all dedicated to minimising the impact of mice and rats in urban spaces.

One small step for rewilding, one giant leap for mouse control

How do we zoom in from a global mission to the mouse trap behind your fridge? Our new trap isn’t about eradication or rewilding in a direct sense, but it is a small step in the right direction. By building a better mouse trap, we’re helping people minimise an invasive species without adding toxins to their environment. And – perhaps more importantly – we’re also making the whole mouse control experience much less of a messy, stressy experience for you.

The result is a clever electronic trap that can kill a mouse in a fraction of a second, send a notification to your smartphone via Bluetooth, then auto-reset. With a long-lasting lure and a rechargeable battery, it’s designed for continual use in your home, so you can keep the mouse population in check year-round. Because it records kills, it's also a way to track mouse behaviour and population trends, which we feed back into our trap development and future mahi/work.

Better mouse control inside means fewer mice outside, fewer toxins entering our environment, and more bugs, birds, and biodiversity in our urban spaces. And the more people that get onboard, the more those small, positive steps add up to real change.