The predator-proof fence

The predator-proof fence

Following the recommendation of a feasibility study (Oecologico, 2005), the trust began the challenging task of fundraising for a $1.9M predator-proof fence to circle the 8.2km reserve perimeter. Thanks to the overwhelming public and sponsor support received, Xcluder Fence Company began construction work on this customised fence in November 2006, taking just over two years to complete it. 


Not just any ordinary fence!


Unlike your standard stock or garden fence, this fence has special features that make it a barrier to unwanted predators:

  • Its height, close to 2m tall, stops jumping animals such as cats from getting over the top;

  • A fine stainless steel mesh (25mm x 6mm) is small enough to stop even baby mice from getting through;

  • A smooth, rolled hood prevent climbing animals like possums from getting a grip to climb over; and

  • A skirt that goes underground acts as a barrier to digging animals like rabbits and hares. 

Rotokare's fence follows a ridgeline, making it less likely to be damaged by falling trees.  This path also ensures that the entire headwater catchment is enclosed within the fence, preventing any contaminants entering the reserve from surrounding land.

The fence also has a surveillance system An electric tripwire runs around the top of the fence; if a tree falls on the fence, the wire shorts itself on the metal pigtails through which it passes, and a text message informs the Site Manager of an obstruction. This system allows fast and efficient repairs to be made before any sneaky pests can get in!


Why do we need to fence forests remnants in New Zealand?


Introduced pests and predators are the greatest threats to New Zealand's unique wildlife and habitats. These critters are found throughout the country, and although good control methods exist (poisons and trapping), the fence is currently the most sustainable method of pest-control, reducing their numbers to near zero. Volunteer burn-out or long-term use of toxins are risks the Rotokare Trust wanted to avoid.  

A fence like this allows opportunities for high-level restoration; with a barrier for invading animals, resident pests and predators can be eradicated, making it safe to reintroduce many of our vulnerable native animals.