No, the HeroRATs of APOPO are not a new fantasy series like The Owls of Ga'Hoole. These are actual rats trained by an NGO to detect land mines.

APOPO stands for "Anti-Persoonsmijnen Ontmijnende Product Ontwikkeling" (or "Anti-Personnel Landmines Detection Product Development" in English), and was officially founded in 1997 in Belgium. Today, it's administrative headquarters is still in Belgium, but it's real land mine detection work is done in Angola, Cambodia, Mozambique, Tanzania, and Thailand.


APOPO uses African Giant Pouched Rats (Cricetomys gambianus) for a number of reasons. Rats generally have an excellent sense of smell, are intelligent and trainable, cheap to keep, abundant, and are too light to set off the mines. The African Giant Pouched Rat, in particular, is local to sub-Saharan Africa and adapted to that environment and resistant to its diseases.

APOPO trains its HeroRATS in a facility at Sokoine Univeristy of Agriculture in Tanzania. The facility 240,000 square miles large with 15000 deactivated land mines for the rats to train on. The rats are trained in a way that'll be familiar to a lot of pet owners: clicker training. At the training facility in Tanzania, four-week old baby rats are hand-reared to get them used to humans and are immediately taught to associate the sound of a clicker with food. Accuracy in the rats has been shown to go down rapidly without reinforcement,


They're then trained in laboratory to recognize TNT by smell. They're put in cage with in hole in the ground, which holds a sample of TNT-contaminated sand, and if they leave their nose by it for two (and later five) seconds, the clicker goes off and they are rewarded with banana. Then the samples are varied between those contaminated with TNT and those not. Correctly identifying the TNT samples also gets a click and a banana.

After being consistently correct in the lab, the rats are trained in fields. In the fields, the rats are trained to move while wearing a harness attached to a rope held by two trainers. Then they start identifying the same the stainless steel balls as before, only now they're buried outside. Once they can consistently pass tests finding those balls, they're trained with deactivated land mines. They're trained in larger and larger areas, until they can correctly identify, with no false positives, all the mines in a 100 square mile sized field. In order to travel to an actual mine field, the rats then have to repeat this feat in a blind test, where the trainers are ignorant of the mines' location. This helps to ensure that the rats are actually finding mines, not just reacting to the trainers' knowledge of their locations.


The results are impressive. In 2009, for example, a team of 24 rats in Mozambique searched 93,400 square miles and found 41 mines and 54 other Explosive Remnants of War ("ERW"). Humans with metal detectors didn't find any mines the rats missed. The rats did have a false positive rate of .33 for every 100 square miles searched, but they still met the false alarm standard of the International Mine Action Standards for detection animals.

And in 2008, APOPO was given the task of clearing Mozambique's Gaza province. It completed the job in 2012, a year ahead of schedule. In the process, they searched 7,911, 376 square miles of land, finding 2,587 land mines, 13,051 small arms and ammunition, and 992 bombs.

APOPO also trains rats to detect tuberculosis, where the rats can evaluate more sputum samples in ten minutes than a lab tech can in a day. And APOPO is working on training its rats to remotely evaluate air samples of suspected minefields.


So can we please ditch the stereotype of rats as dirty criminals? Because there are giant rats being trained to save lives.