Why is the fence so floppy?
At first glance, Arid Recovery’s perimeter fence appears to be in need of repair. At the bottom it looks straight and strong, but at the top it curls over on itself. It’s floppy!
That is exactly how this purpose-built fence is supposed to look.
Arid Recovery’s tried and tested floppy fence design is its best defence against feral cats, foxes and rabbits, and is vital to the survival of all the threatened species that now call Arid Recovery home.
The fence was designed through much trial and error. Cats and foxes were repeatedly released into a trial fenced area and the fence was modified until they were unable to escape.
The result was a 1.8m tall fence with foot netting along the bottom and a floppy overhang at the top. Foxes can’t get under it, and cats attempting to climb up and over the fence will attempt to pounce on the floppy top, which then flops down and flings them back to the ground.
The Main Exclosure is Arid Recovery’s original 14 km2 fenced area, where native animals were first introduced. The fence around the Main Exclosure is 1.8 metres tall and has two electric wires running around it.
Fence designs developed at Arid Recovery. Figure adapted from Moseby and Read 2006.
However, the floppy top proved so effective at keeping ferals out that the fences around the perimeter of the subsequent 1st, 2nd and Northern Expansions were only built 1.15 metres tall and were not electrified.
Early on, founders Katherine Moseby and John Read discovered that young rabbits could slip through the 40mm wire “vermin-proof” mesh. Subsequently the mesh around the bottom 90cm of the fence was replaced with 30mm to make Arid Recovery one of the few large rabbit proof reserves in the country.
Perimeter checks of the fence are made regularly to check for any damage to the fence. Checks after major storms are particularly important as strong winds can blow the floppy top inwards and heavy rain can cause washouts which may allow feral animals to penetrate the fence.
Heavy rains can cause damage to our feral-proof fence. Photo by Hugh McGregor
Damage to the fence can also be caused by fighting male red kangaroos that can pop the layers of mesh open at roo kick height.
Despite our best efforts at maintaining the fence, feral cats are particularly intelligent, and if given enough time may learn how to breach the floppy top or take advantage of any temporary weak points in the fence. To prevent this, permanent traps have been set up around the fence perimeter and a team of volunteer shooters goes out regularly to reduce the numbers of introduced predators around the reserve (read more here).
Written by Rachael Loneragan (March 2017)