Frequently Asked Questions

What does APOPO mean?
APOPO is an acronym from the Dutch Anti-Persoonsmijnen Ontmijnende ProductOntwikkeling meaning Anti-Personnel Landmines Detection Product Development.

Are rats likely to get killed in the detection process?
HeroRATs are trained to detect and pinpoint the location of a landmine. Their size and weight make it highly unlikely they would set of a pressure-activated mine by scratching or pointing. It is a misunderstanding that the rats are trained as Kamikaze to destroy the mines in the field. Trained animals are far too precious to lose to landmines. On the contrary, the rats used by APOPO are treated with great care and attention in order to optimize their physical and mental condition.

What kind of rat is trained to sniff out mines and disease?

Rodents are the biggest order of mammals, with more than 2,000 species. Among these, APOPO selected the African giant pouched rat or ‘Cricetomys gambianus’ for mine detection. Though most rats could qualify in terms of sensitivity and intelligence, the Cricetomys has inherent advantages for the mine-detection task.

African giant pouched rats are:

• a widespread indigenous species, adapted to the local environment.
• able to live up to eight years in captivity, optimizing the return on training investment.
• relatively large, making them easier to work with and observe.
• calm, docile, and easy to tame.

Being a wild species, it was assumed that their olfactory capacity would be very well developed.

African giant pouched rats weigh between 0.7 and 1.5 kg, and their average body length is 30-40 cm, excluding the tail of 40 cm. They live in burrows underground, where they usually have different chambers. They collect food and other items in their pouches, store them underground, and always trace their path by sense of smell – behavior similar to the demining task. Being nocturnal, they are relatively calm and manageable during the day, though they are prone to heat strokes if exposed to excessive sunlight.

Can rats smell better then dogs?
Dogs are traditionally renowned for their tracking and sniffing capacities. Can rats match their performance? In the wild, rats can communicate over large distances using olfactory cues – and the rat’s nose is constantly active and moving. With its rather poor vision, the Cricetomys depends largely on its sense of smell.

Rats have a clear advantage over dogs – the rat’s nose is always close to the ground, even when its head is raised. (The highest vapor concentration and the lowest wind speed are found close to the ground.) Although trained with TNT, it is not clear which of the nitro-aromatic compounds, or even mine-casing materials or other cues, are most detectable by the animals. Therefore, it is always necessary to re-calibrate the animals on the specific targets found in the demining operations.

How are the rats trained?
APOPO uses a combination of click training and food rewarding. Training starts at the age of five weeks, when juveniles are weaned from the mother. At first, the animals are nursed for one week by the caretakers so they can get used to humans. Then they are taught to associate a clicking sound with a food reward. After that, they have to perform certain tasks to get this reward. After odor imprint, the complexity of their tasks gradually increases.

Perhaps the main difference between dog training and rat training is that rats are not taught obedience. Therefore, the total training period can be relatively short. In APOPO’s experience, the field rats can be trained within eight to 12 months, and REST rats between six to 10 months.

Intellectually, the rats are 'smart' enough to learn required tasks relatively quickly, while being ‘uncomplicated’ enough for learning to be standardized. Food provides a strong and controllable source of motivation and an effective drive for performance.

How long can a rat work?
Normally, the rats are trained about half an hour per day, five days per week. During this period, they are on a food-for-work diet. During the weekend, they feast on an extensive varied meal.

In the REST analysis, rats can evaluate between 100 and 150 filters in about 15 minutes. In the field, the free-running rats scan a 100m2 box in an average of 30 minutes. They can do two boxes in one session.

HeroRATs can live up to 6 or 8 years. Conservatively, we estimate they can work in the field for up to four years.

Are they resistant to tropical diseases?

Veterinary care requirements are relatively small for African giant pouched rats. Since they are endemic to sub-Saharan Africa, they are less vulnerable to local diseases than imported animals. Routine care includes daily observations of individual animals, weekly health reports, and regular prevention treatments for endo- and ectoparasites.

What do rats eat?

During the week, trained rats live on a reward diet that consists mainly of bananas and peanuts. On the weekend, they eat a balanced diet of grains, maize, nuts, vegetables, fruits, fish, and sometimes insects. This is also the permanent diet for the breeding rats. Rats generally eat a great variety of food, and food supply is rarely a problem.

Do they need a lot of care and attention?
Captive-born rats enjoy attention, including being petted and being taken on daily walks. APOPO has several outside pens where the rats can play and get used to an outside environment. Other rats walk around freely in the kennel during clean up of their cages – they don’t attempt to escape, they just wander around and explore new environments.

Are there any cultural problems with handling rats?
In APOPO’s experience, all trainers who have been employed to train the animals (mostly Tanzanians) have picked up the job quickly. There have been no cases of fear among the trainers or cases of mistreating or rough handling of the rats, behavior that could initiate fear in them. In general, we observe quite gentle handling and respectful interaction with the animals. Based on this positive experience, APOPO expects that users in the demining community will quickly get accustomed to this new approach. Future experience at different locations might reveal cultural differences related to the acceptance of mine-detection rats. There have been some areas where demining dogs were not appreciated on religious grounds. Thus far, the initial reactions of the beneficiary communities and demining organizations have been very positive.

Can different people handle one rat?
An important advantage of the rats is their relative independence from a personal handler. Generally, most rats remain with the same trainer, but show no significant difference in performance when taken over by somebody else in the absence of the trainer. Preferably a new handler should be briefed on the specific behavior of individual animals. This has a logistic advantage in that a handler does not necessarily have to follow his own animals to the demining operations.

What does a trained rat cost?
Rats have a definite cost advantage in terms of maintenance and care, duration of training, as well as kennel and transport requirements, whereas their time span of operational efficiency is similar that of mine-detection dogs. An exact cost calculation of the rodent mine detection technology will only be possible after relevant operational field experience over a period of time. However, at present we estimate that 5 euro per month covers basic food, nutrition, and healthcare for one rat. If you factor in all the variables that go into training, evaluation, and care, it costs an average of 6,000 euro to fully train one mine-detection rat. This cost is roughly, one-third to one-quarter the cost of a fully trained mine-detection dog. A cost comparison between training dogs and rats can be made with a detailed cost analysis of mine-detection dogs.

Will rats oust dogs as mine-detection animals?
In fact, mine-detection rats and mine-detection dogs are complementary tools within the mine-action technology toolbox. One allows for quality assurance of the other, whereas both techniques can be deployed as primary detectors.

For the use of rats in the open field, we noticed that rats are good at scanning high-density minefields. They seem to be able to pinpoint mine positions easier than dogs under such conditions. Dogs, however, can cover bigger distances, and are better in a fast survey. The specific advantages of the use of rats in the REST system are obvious; their small size allows a REST set-up to be small and easily managed. This is reflected in a faster working speed and changeover of samples. Rats also tend to work in a more ‘mechanical’ way than dogs.

Dogs have the distinct advantage of being used in mine detection for decades. Consequently there are a lot of training companies and many experienced dog trainers. It might take considerable time and effort for mine-detection rats to reach the same level of acclaim.

How do you find work for the rats? Are you hired by governments to demine?
APOPO has full demining operations under AMAT (APOPO Mine Action Team) in Mozambique. AMAT consists of three-part integrated system, which consists of bush cutting, rat mine detection, and manual clearance. When AMAT is assigned full demining tasks, we handle the demining of that area from start to finish. This means we clear the vegetation, use rats to identify the mines, and then manually demine the area. APOPO also provides mine-detection services to partner NGOs and external demining operators.

Once the Mine Detection Rats indicate the location of a landmine, how do you remove or destroy the mine?
The locations that are indicated by the rats are then followed up by our manual demining team, who detect and destroy the mines. A deminer first locates the mine and exposes it to a level where it can be clearly identified. The exact location is clearly marked with warning signs, and at the end of the day, the supervisor will come back to it and lay a demolition charge next to it. Then they stand off to a safe distance and detonate the explosive, which destroys the mine.

Can I visit your training center in Tanzania?
Yes, we welcome visitors! Please send us an email to let us know when you would like to come to our facility, and we will provide you with directions and meeting details.

What’s a typical day at APOPO in Tanzania look like?
Our rats work Monday through Friday and play on weekends. During the week, landmine-detection training occurs in the mornings between 7 am and 9 am. Afterward the trainers return to the office for tea and breakfast. From 9:30 am to noon, trainers work with the REST rats and TB-detection rats in their respective centers. They also work with the young rats that are just beginning their socialization and early-stage training. Lunch takes place from noon to 1 pm and trainers wrap up their training – and prepare for the next day’s work – from 1 pm to 2:30 pm.

Where do you get your rats?
APOPO breeds our heroes in training at our center in Tanzania. Successfully trained rats that are taking a ‘work holiday’ also participate in our breeding program. African giant pouched rats only have two to three litters a year, and only an average of about three young pups are born in each litter.