Femi scratches at the moist surface. Something metallic appears from beneath the soil. A dry clicking sound makes her run to her trainer, who gives her a piece of banana. The young female is a giant pouched rat with an excellent sense of smell, which makes her ideal for the task of detecting land mines.
By Ilona Eveleens, Tanzania
Femi and other rats are trained to find land mines by the Belgian-Tanzanian APOPO company, based in the Tanzanian city of Morogoro. The animals are tested and accredited in accordance with international standards. They have to score one hundred percent before being certified and deployed in land mine-ridden countries like Mozambique. During the country's civil war, which ended in 1992, approximately half a million landmines were laid, half of which have been cleared by now.
“Rats are much faster in detecting mines than humans,” reveals Hannah Ford of APOPO. “In twenty minutes a rat can search an area of one hundred square meters for land mines; a de-miner would need a full day.” None of the rats weigh more than one and a half kilo, far too light to detonate a landmine.
Next year APOPO will send supplies of rats to Angola, another country struggling with millions of land mines left behind after the war, which ended in 2002. APOPO has already been training mine detection rats for ten years, but they are still not being used on a wide scale. “Rats generally don’t have a good reputation with people. But these giant pouched rats are intelligent, sociable animals with a high level of trainability,” says Hannah Ford, while one of the rats softly licks her hand.
When Femi’s training is finished, her tiny harness is taken off, but she does not run away. She hops after trainer John Mosha to her travel cage. “She knows she gets food from me. That is the whole trick of the training,” says Mosha. “When she works well, she has her tummy filled, if not she has to wait until she is back in her living quarters to get fed.”
Other rats in Morogoro are trained to detect tuberculosis (TB). One of them is Astrid. She works in a glass lined cage with a metal floor. The floor has little holes. The rats are trained to sniff at the holes under which samples of sputum are placed. When Astrid sticks her nose in one of the holes that contains a TB positive sample, and keeps it there for four seconds, a clicking noise is sounded. The click means ‘reward’ in the form of a bite of mashed banana or avocado.
“Each week we receive hundreds of sputum samples from hospitals. Astrid and her colleagues not only confirm laboratory results, but detect on a weekly base five to ten extra TB cases, that hadn’t been found in the laboratory,” says Ford. New cases are verified with microscopy and in most cases the rats are proven right. In this line of work, the rats are faster than laboratory technicians. Human experts need a full day to screen forty samples, while it takes a rat less than seven minutes to do the same.