Electric fencing for wild animals.
I don't recall anyone on graze-l mentioning the voltage required to
control predators.
In case some don't know, when I was the group marketing director for
Gallagher in the early 80s and spent about six weeks around the world
three times a year for five years, we recommended at least 3,000
volts on the fence, and I preferred 4,000, to control all except
cattle which can be controlled with less. At that time only New
Zealand made energizers could maintain this on long and dirty fences.
Even a little less than 3,000 volts and sheep, deer, goats, 'wild
dogs', elephants, etc., will get through.
The term 'wild dogs' was used in Australia because some people didn't
like farmers shooting dingoes.
The first shock has to shake the devil out of predators, and be so
strong that it is the last one.
Before Gallagher arrived, elephants in Malaysia would get a small
shock from a "charger" which just made them cross so they would storm
through the fence and wreck the homes of rubber and other
plantations' staff who then didn't like the use of electric fences.
Previously the elephants would walk around their houses and not worry
them. We had to put up a demo fence to show it worked, after which
hundreds of miles were erected.
High power Gallagher energizers give excellent control over many
miles per energizer.
Some countries dug trenches to keep elephants out of crops, but some
elephants would push the soil in at some places and walk across. One
high-power wire at the top of the trench on the crop side worked well
and clearing the trees back a few chains helped.
Wild pigs were a problem in Holland where low power and fences with
the bottom wire too high taught them to get through. High power and
fences like FW described fixed them. They would start screaming a few
metres from the fence and then rush at it, but if they got through,
after a 4 or 5,000 volt shock they would then not come out. At least
one farmer then corralled them and sold them to pig hunters. They
would take one to a forest hunting area, let it go and then follow it
to shoot it. Sport!?
Piglets need a really low wire.
In Yugoslavia the Gallagher agent won a crate of beer from a farmer
when he sold and constructed a boundary fence which kept sheep in and
wolves out. After a while they left the sheep out at night and were
relieved to see them safe in the morning. However, since then there
have been wolf killings of sheep, showing that as written by some,
the predators keep working out ways to get their prey, but did the
voltage drop as it does on old fences which are not kept clean and
maintained.
Offset live wires outside and inside help tremendously because the
'jumper' has difficulty estimating the width of the fence. Offsets
also make the predator and wild deer keep further back from the fence
which again makes it harder from them to work out how to get through
or jump it.
If I had a predator problem I would aim to maintain about 5,000 volts
and a high joule figure on the fence.
--
Vaughan Jones
