An email was received requesting help on why a fox had been able to penetrate an electric netting system and slaughter 150 hens. 150 hens taken by one fox is quite a catastrophe and by far the largest we have come across. The image below indicates the scale of the predation.

The enclosure utilises standard poultry nets on a 12 joule energiser, so seriously powerful and illegal in Europe. It has been in position for over 4 years without incident.

Looking at the image there is quite clearly a serious challenge from a thick sward of lush green grass. This has to be drawing all the energy from the net despite the strength of the energiser. Each blade of grass touching the net will be drawing off a bit of energy to the extent that even a powerful 12 joule energiser will be unable to overcome this draining of energy resulting in a low voltage reading on the fence. It is the effect of encountering this shock delivered by the voltage in the fence that provides the protection.

Unfortunately we have not been told what the voltage reading is on the fence as the correspondent has gone quiet on the issue.

In order to fully protect animals it is necessary to maintain a voltage in excess of 5000v in a net to be fully effective and deny entry by a predatory fox to a poultry run.

It has been proved in two authoritative trials that a fox will not burrow under nor jump over a functioning fence so rendering a pen safe.

Unfortunately, this goes to illustrate that a fence is only as good the maintenance and attention applied to the protective measures necessary to provide an effective barrier. This is comparable to the statement that a chain is only as strong as its' weakest link. We believe that in this case maintenance has proved to be the weakest link.