Everyone has heard about “hero animals” before- brave dogs, cats, and horses that have rescued humans from dangerous situations. When we think “heroic”, the rat is not usually the first animal to come to mind, but a group of giant rats in Cambodia are well on their way to changing our minds.
After the Vietnam war, much of the land in Laos, Cambodia, and Vietnam was left filled with land mines and, as a result, unusable. The leftover mines also led to many accidents, killing many people and leaving survivors with painful injuries and a need for prosthetic limbs.
In 1997, the Belgian nonprofit organization APOPO began training rats to locate land mines. These African giant pouched rats, or Gambian pouched rats, are nearly two feet long and have an amazing sense of smell. They may be large for rats, but they are still light enough to easily walk over land mines without detonating them. Their relatively small size also makes them cheaper to feed and easier to transport than the trained dogs that were previously used to search for mines. If the rats are properly socialized around humans when they are young, they are also able to work with different handlers much more easily than dogs.
The rats begin their training at five weeks old, and are taught to detect the smell of TNT by being rewarded with food. The rats also learn to avoid the extra smells, like coffee grounds and oil, that their trainers may place nearby to throw them off. Since the rats locate land mines by the scent of TNT instead of looking for metal, they are faster and more efficient than a metal detector. In fact, they can search an area of 200 square meters in only 20 minutes- a person with a metal detector would take up to four days to search an area of the same size.
The rats search fields on harnesses and tethers. When they find a suspicious spot, they scratch at the dirt to mark it. Human de-miners come back later to investigate further and remove the mines.The rats are rewarded for their work with peanuts and bananas.
Since the rats have started working, they have cleared over 260,000,000 square meters of land, and if they continue to be approved in other countries, perhaps these heroic rodents and their super-powered sniffers will eventually get rid of dangerous leftover explosives once and for all.
