Rat sniffing landmine. Photo by Xavier Rossi, courtesy of Apopo's Herorats

It costs as little as €2 to place a landmine, but it can cost as much as €700 to clear one. That difference underscores the challenge in clearing antipersonnel mines. Some traditional methods, such as using metal detectors and trained dogs, are still expensive and time consuming. But in southern Mozambique a more cost and time-effective approach is being used with remarkable success: rats.

Bart Weetjens, a Belgian product engineer with a lifelong love of rodents, first thought about it after reading a scientific article on the olfactory skills of gerbils in detecting explosives. If dogs were being used to find landmines, why couldn't rats do the same? Weetjens, whose work centred on making prosthetics sustainable, decided instead to focus on detecting the landmines that cause those injuries. Africa has the largest number of landmine victims in the world, so he established himself in Tanzania, where his NGO, known as APOPO, is still based.

Rat and operator with landmines. Photo by Xavier Rossi, courtesy of Apopo's Herorats

Despite widespread scepticism, Weetjens's idea proved successful and de-mining began in 2004 in the Mozambican province of Gaza. To this day, APOPO's rats have cleared over 1 million square metres of land in the impoverished country. Mozambique, which was left riddled by mines after a 16-year civil war that ended in 1992, is now on track to become landmine-free by 2014.

Today, Apopo has 45 trained African giant pouched rats operating in Mozambique. Another 300 are in various stages of training at facilities in Morogoro, Tanzania.

Landmines. Photo by Xavier Rossi, courtesy of Apopo's Herorats


Rats detecting landmines. Posted by Apopo on YouTube

Sniffing out tuberculosis

Rat smelling sputum samples. Photo by Sylvain Piraux, courtesy of Apopo's Herorats

APOPO also discovered that rats are very good at evaluating sputum samples to detect tuberculosis, one of the biggest health problems in the world today. While a lab technician can only go through 40 samples in a day, one rat can process 70 samples in ten minutes.

The programme, currently in its development stage, is being validated as a second-line screen in four hospitals in Dar es Salaam (Tanzania). Each week the rats find an average of 5 to 10 patients with active TB whose condition had not been detected by microscopy in hospitals.

Setting up a safe working perimeter

Rats setting up work perimeter. Posted by Apopo on YouTube.


“Our rats are not trained as kamikaze to detonate landmines. They are far too precious to lose”

Courtney Baggett, based in Portland (USA), works with APOPO.

Why rats? There are several reasons why we chose them. For a start, rats have an incredibly good sense of smell. They can easily use it to find explosives and, unlike metal detectors, can detect both metal- and plastic-cased landmines. Second, they are light and won't trip off mines when they stand on them. It takes about 5 kilograms of weight to detonate a landmine, whereas a rat weighs three times less.

Finally, rats are as efficient as dogs, but easier to breed and cheaper to feed, maintain and transport. To train a rat costs around €6,000, almost four times less than training a dog, and with €5 per month we can provide food and care for one rat.

A common misconception is that our rats are trained as kamikaze rats to detonate landmines. After training them for up to a year, they are far too precious to lose. On the contrary, we love them greatly; we take very good care of them and expect them to live up to their life-span of six to eight years.

Rat and operator. Photo by Xavier Rossi, courtesy of Apopo's Herorats

To find landmines the rats go through a rigorous training programme in which they first learn to associate the sound of a click with food. Then, they are introduced to TNT-spiked soil samples: they are trained to associate these samples with a clicking sound, and receive a reward such as peanuts or a piece of banana. When they are on the field, the rat will scratch the ground to point out a suspicious spot, and the person accompanying it will make a clicking sound and hand out a reward.

Rat receiving reward. Photo by Eric Nathan, courtesy of Apopo's Herorats

On average, one rat can clear 200 square metres in 30 minutes, the equivalent of two days' work for a manual de-miner. A team will then detonate the landmines that are found."

Rat and landmine victim. Photo by Xavier Rossi, courtesy of Apopo's Herorats

Working. Photo by Sylvain Piraux, courtesy of Apopo's Herorats

Rat sleeping quarters in Mpelane, Mozambique. Courtesy of Apopo's Herorats