From Colombia to Afghanistan, millions of landmines from conflicts past litter the land and continue to wreak havoc on unsuspecting civilians, particularly children. But one group has hit upon a fascinating solution to this grim problem. I highlighted the program here before, but as NPR reports, it is starting to cover more ground — literally.
A Belgian nonprofit called Apopo began harnessing the rodents’ olfactory prowess 15 years ago. (The group also trains rats to detect tuberculosis). The organization set up a breeding program and training center in Tanzania and began deploying rats to post-conflict countries, first to Mozambique and Angola. Apopo’s Cambodia program began in April, in partnership with the Cambodian Mine Action Center.
“The idea was very strange,” says operations coordinator Theap Bunthourn. “Cambodian people kill rats, don’t like rats. But they’re cost-efficient, they’re easy to transport, they’re easy to train, and they don’t set off the mines because they’re too light.”
That’s an advantage over mine-sniffing dogs, also used in Cambodia. And unlike with dogs, says field supervisor Hulsok Heng, bonding is not an issue. “The rat does not belong to anybody, it can work with anyone, not like [a] dog. If [a] handler is sick, [a] dog cannot work with other people. If the dog does not recognize you, it won’t work with you. But rat, no problem.”
Fifteen rats arrived in Cambodia from Tanzania in late April. Since it’s hotter in Cambodia than in Tanzania, Hulsok says, they’re put to work before the sun comes up. By midday, it’s too hot for them.
With 4-6 million unexploded landmines, bombs, and grenades, this Southeast Asian country could definitely use the help. Neighboring Laos and Vietnam are just as badly affected, so hopefully this field run will prove fruitful enough to expand to those nations as well.
The process of detecting hidden ordnance by rat is pretty fascinating, to say the least.
One rat, named Victoria, ambles down a 10-yard stretch of grass, tethered to a line held by handlers on either end.
“She’s very good today, very fresh after the rain last night,” Hulsok says before showing me the mine planted about 7 yards away. As Victoria gets close, maybe a foot-and-a-half away, she stops, sticks her nose up high in the air and seems to lock on to something. She takes another half-step, then scratches the ground. It’s the signal that she’s found the mine.
“After the rat pick[s] up the scent and scratches,” Hulsok says, “we give her a food reward, like a banana.”
No TNT, no banana. The rats learn this through repetition. They also learn not to fall for the tricks the handlers use to try to fool them. These can include “the smell from a battery, oil filter, car filter, tuna fish can that we use to confuse the rat,” Hulsok says. “Because if they scratch on another smell, we give no food, no reward. Only reward TNT smell.”
Another rat, the rock star of the group, named Pit, has already identified two mines this morning. She is just about to reach the spot where they’ve planted a decoy, known as a “dummy.” Pit isn’t fooled by the dummy — not even for an instant. She “smells only TNT,” says Hulsok.
What about the other rats? “Sometimes they scratch for the dummy. But we don’t give them food,” he says. “Then the rats will learn. But some rats are more clever than others. Just like people.”
Who could have imagined that rats, as underratedly clever as they are, could be used for safely clearing one of the bloodiest scourges of war. These critters have already made incalculable contributions as the go-to test subjects for everything from psychological studies to cutting-edge cancer treatments.
Not only do rats prove to be fairly accurate, but they are a lot more cost-effective as well.
Apopo’s James Pursey says it costs about 6,000 euros, or $6,500, to train each rat. They can live from 6 to 8 years in captivity. At the Cambodian Mine Action Center training camp outside Siem Reap, it’s a pretty good life. The rats are kept in individual cages in an air-conditioned room “because we want to protect our investment, take care of them,” says Theap, the operations manager. “We want to keep them good and healthy all the time, so they can perform [with] more efficiency.”
There are still some skeptics, even in the demining community, who won’t trust a rat. Hulsok isn’t one of them. He’s been looking for and clearing mines and other unexploded ordnance for more than 20 years. In the case of certain mines, he says, he’d trust a rat over a metal detector any day.
“One type of mine from Chinese, we call 72 Alpha, the metal is very, very small, very, very small detonator and pin,” he says. “But a rat can smell TNT very good, so [it] can pick up that mine. But it’s good if we have both. Without [a] mine detector, it’s not easy to work.”
In other words, the giant African rats are just one tool in the demining kit — not meant to replace dogs and machines, but to augment them, helping make it quicker and easier to deal with the legacy of the country’s brutal past.
The rats are closely monitored and regularly tested to ensure they remain reliable as they age. Once they reach a point of being too tired or inaccurate to do their job, Apopo allows these living mine detectors to live out their lives until they pass away. If all goes well, they should begin work on clearing live minefield this fall. Here is hoping.