Sheep that call home

WHEN the sheep call home in South Africa, something bad is going down in the paddocks.
Nanjing Night Net

In a country rife with small-time stock theft and stray dogs, about 1000 South African farmers have equipped their sheep with a collar that detects panicked movement and makes a mobile call to alert the owner of likely trouble.

Since the first version of the collar was launched in 1999, farmers have prevented the loss of about 300,000 sheep, according to Philip Lötter, who developed the concept.

Each collar carries its own SIM card. When triggered by the sheep’s movement, the device dials the farmer’s mobile with a unique number that identifies the collar.

The collars are also capable of sending SMS messages – to report that the sheep carrying the collar has died, that the batteries need charging (every month to six weeks), or to report in for duty each evening.

The collars can be programmed to switch on and off over four blocks every 24 hours, saving battery power by only switching on at times of the day when attacks are most likely to occur.

They are also individually tuned for each farmer’s management. Many South African farmers put their sheep in kraals overnight, which requires different programming to those who leave them in paddocks.

The main limitation to the device is that it needs a mobile phone signal to operate. This aside, the concept appears to answer the prayers of many Australian farmers kept awake at nights by the threat of wild dog attack.

As a farmer near Cape Town in the 1990s, Mr Lötter was himself the target of multiple sheep thefts. In the late 1990s, tired of restless nights, he went to Stellenbosch University and asked if the researchers could devise something that would count the number of steps a sheep took.

The idea – then and now – was to have a device that could detect when a sheep’s movement patterns changed from the norm for a certain period of time.

When this behaviour was detected, the device then had to send an alert to the farmer.

Professor Jurie Krantz rose to the challenge, and a first-generation radio-based device was produced by Etse Electronics.

Mr Lötter formed a company, Celmax, around the invention, which is now in its fourth generation.

The latest collar sells for R5400 ($620). In South Africa, this cost can be recouped by preventing the theft of four ewes.

Collars tend to be put on only one sheep in the mob, because the behaviour of one sheep tends to reflect the behaviour of the rest.

It is also used on goats and “certain types of cattle”, Mr Lötter said. The problem with many cattle is that they will allow themselves to be worked quietly at night, so the devices fail to trigger.

Celmax has received calls from Australian producers interested in using the technology to protect their own livestock.

Mr Lötter said he is keen to have an Australian presence, but it will require professional support to ensure the collars are tuned correctly.