How to build a backyard trapping tunnel

Department of Conservation —  19/10/2017

It’s Conservation Week from the 14th – 22nd of October. You can get involved by protecting the native species in your neighborhood from rats and mice. To do that you’ll need a trap and a trapping tunnel.

A trapping tunnel is a box to put a rat trap inside (and optionally a mouse trap in behind the trap). The tunnel is designed to protect your young family members and pets from the trap.

If there is a Predator Free community near you, they will likely have trapping tunnels ready to go, but if there isn’t a group nearby, or if you’re up for a challenge, you can make the tunnel yourself.


Building a trapping tunnel with Predator Free Mt Cook & Newtown

These instructions come from Predator Free Mt Cook & Newtown, who recently had a working bee to build trapping tunnels. They managed to make 164 in one day! Don’t worry though, you’ll only need one or two for your back yard.


Predator Free Mt Cook & Newtown’s mammoth mountain of trapping tunnels

What you will need:


4 x planks of fencing timber (150mm x 25mm x 500mm)
10 x 60mm jolt head nails
1 x 75mm flat head nail
7 x staples
1 x front mesh screen (with opening cut out using wire cutters)
1 x back mesh screen
1 x rat trap (and mouse trap optional)


Wire cutters



Sourcing your materials:

You can find everything you need at your local hardware store. Ask someone in the shop for help finding the right types of nail and staple. They can help you choose the right mesh too.

When it comes to the fencing timber, you’ll find it in long planks in store. If you take these up to the counter they will be able to cut the plank into shorter (150mmx 25mm x 500mm) lengths for you. So you don’t need a saw!

When it comes to traps, we recommend Victor Professional rat traps, which you can buy online.

Now you have everything, you can get started with construction.

Step 1: Fasten the bottom to the sides

Hammer a 60mm nail into each corner of the bottom piece through to the walls. It’s a bit fiddly to hold the pieces in the correct position, so you may need some help for this. Add a nail to the centre of each side for added strength.


It should now look like this:


Step 2 – Nail the lid on

Line up the sides to the lid and nail in each corner.


Step 3 – Staple on the front mesh

Fasten the front mesh to the tunnel by hammering a staple into each corner. Ensure the entrance hole is level with the top of the bottom piece of wood.

You can see that we have added an extra block of wood to the top of the trap for stability, but this is optional.


Step 4 – Staple on the back mesh

Flip the box over and hammer a staple vertically to the bottom corners of the back mesh – the mesh should hinge open like a door:


Hammer the final staple in the centre of the top piece of wood just above the top wire of the mesh. Hammer it in so the 75mm nail can be inserted through the staple without being too loose. The nail holds the door closed.


That’s it, you’re done!


Now you’re ready to set it up. Check out our recent blog post on how to trap to find out more.

If you’re interested in joining a group like Predator Free Mt Cook & Newtown, check out the Predator Free NZ website.

We use the DOC 150 trap for stoats, rats and hedgehogs. More about the DOC 150 trap can be found here

It’s Conservation Week from the 14th – 22nd of October. Get involved by protecting, growing, nurturing and caring for our nature.


Please note that it is an offence under the Animal Welfare Act 1999 to use any inhumane methods to dispatch of predators. Approved methods for dispatching of predators using kill traps are outlined in our PF2050 trapping guide. All of these traps have been approved by the National Animal Welfare Advisory Committee and comply with The Animal Welfare Act 1999.

6 responses to How to build a backyard trapping tunnel


    Great tutorial. Will take a vacation and try to build backyard myself with my kids: )


    Excellent. Ty DOC. Just what I need for my backyard. Now I can fire the cat 😀

    Read your article re your adopt a stream or waterfront in fb I think it was, recently.

    In two yrs time I will adopt approx 5 km of the Kaihu Stream in Dargaville Northland. From where it feeds into the Northern Wairoa River at Mangawhare Bridge which in turn feeds the Kaipara Harbour, to up past Station Rd Drgvl and maybe into the Parore Basin(?) I.E. the first of the Kaihu Stream adjacent farms.

    We all know how important the Kaipara Harbour is.

    Water quality testing at the NW River outlet near the Mangawhare Bridge will be high on my agenda.

    Cheers for the idea. DN.


    shared on FB – great to get the instructions, thanks

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