Rats in Tanzania are being trained to sniff out landmines so de-miners can more quickly and efficiently clear explosives from the ground. It takes two de-miners a day to clear a 2,150 square foot minefield, but if they work with two rats they can sweep it in two hours.
Every hour a person is maimed or killed by a landmine somewhere in the world. There are more landmines in Africa than anywhere else. Finding and removing them is expensive and extremely dangerous.
Traditionally, dogs have done the job of sniffing out landmines. But rats are lightweight and less apt to set off a mine. They have an acute sense of smell, are not as susceptible to tropical disease as canines, are easily motivated by food, and they work well alongside humans once trained.
Rats are also much less costly to maintain than dogs.
The landmine-sniffing rats are trained Pavlovian-style. When a rat stops to sniff the odor of an explosive, the trainer alerts with a loud click (using a clicker similar to those employed by some dog trainers) and gives the rat a food reward.
Field training involves planting mines with detonators removed for the rats to detect. The rodents wear little vests attached to a cable that runs between two trainers.
The rats move in a straight line along the cable, and when they locate a position over buried explosive material, they signal by scratching the ground.
After nine months to a year of training, the rats find the explosives with amazing speed.
Rats are also being used to detect tuberculosis (TB) in lab samples. TB is a leading cause of death in Africa. A lab tech can only test around 20 samples a day, but a single rat can test up to 2,000 samples in the same day.
The uses for rats in detecting smells are limitless. The founder of the Tanzanian ‘Hero Rat’ project, Bart Weetjens, thinks the next frontier would be to use trained rats to sniff out narcotics or to search for survivors of disasters such as earthquakes or collapsed buildings.
Video of hero rats at work in Mozambique.