'Hero Rats' Sniff Out Danger in War Zones

Rat peeking out from wood

Rats in Tanzania are being trained to sniff out landmines so de-miners can more quickly and efficiently clear explosives from the ground. It takes two de-miners a day to clear a 2,150 square foot minefield, but if they work with two rats they can sweep it in two hours.

Every hour a person is maimed or killed by a landmine somewhere in the world. There are more landmines in Africa than anywhere else. Finding and removing them is expensive and extremely dangerous.

Traditionally, dogs have done the job of sniffing out landmines. But rats are lightweight and less apt to set off a mine. They have an acute sense of smell, are not as susceptible to tropical disease as canines, are easily motivated by food, and they work well alongside humans once trained.

Rats are also much less costly to maintain than dogs.

The landmine-sniffing rats are trained Pavlovian-style. When a rat stops to sniff the odor of an explosive, the trainer alerts with a loud click (using a clicker similar to those employed by some dog trainers) and gives the rat a food reward.

Field training involves planting mines with detonators removed for the rats to detect. The rodents wear little vests attached to a cable that runs between two trainers.

The rats move in a straight line along the cable, and when they locate a position over buried explosive material, they signal by scratching the ground.

After nine months to a year of training, the rats find the explosives with amazing speed.

Rats are also being used to detect tuberculosis (TB) in lab samples. TB is a leading cause of death in Africa. A lab tech can only test around 20 samples a day, but a single rat can test up to 2,000 samples in the same day.

The uses for rats in detecting smells are limitless. The founder of the Tanzanian ‘Hero Rat’ project, Bart Weetjens, thinks the next frontier would be to use trained rats to sniff out narcotics or to search for survivors of disasters such as earthquakes or collapsed buildings.

Video of hero rats at work in Mozambique.

Rats are another loathsome species -- creatures that for whatever reason (the way they look, or smell, or false beliefs about them) get a bad rap. But when we’re willing to open our minds a bit and take a closer look at species that sometimes give us the creeps, we’re often surprised and humbled by what we learn.

The African Giant Pouched Rat

The species of ‘hero rat’ being trained by Mr. Weetjens’ organization is the African giant pouched rat, Cricetomys gambianus, also called the Gambian giant pouched rat.

Not much is known about this species of rat, except it is endemic to all of sub-Sahara and Africa, lives up to eight years in captivity, and is docile and friendly to humans.

Full grown, these rats are well over two feet in length from the tip of their nose to the tip of their tail. They weigh in at about three and a half to four pounds of solid muscle.

The African giant pouched rat stores its food underground and is able to find a previously buried cache of chow with its nose. This is probably why this particular type of rodent is so competent at detecting underground landmines.

The African giant pouched rat is nocturnal, but each animal is an individual with slightly different preferences – some are early risers and some like to sleep in a bit.

How the Rats Are Trained to Detect Target Smells

Baby rats in the training project are weaned at four weeks, which is when they open their eyes. They are immediately socialized to people, so they learn humans are friendly.

At six weeks, the young rats learn to associate the sound of clicks with food rewards. Once they know that click means food, the only clicks they hear from that point forward are when they identify a target smell – in this case, the odor of explosives. Most rats naturally develop a scratching behavior when they smell a target scent.

The rats are also taught to walk on a harness out in the open. This is necessary to socialize them to the sights, sounds and smells of the outdoors so that when they are at work, they won’t be easily frightened or distracted.

In addition to their work with landmines, in 2009 Mr. Weetjens’ hero rats also detected 561 people with tuberculosis whose diagnoses had been missed in laboratory tests.

The Weetjens rats are self-sufficient and transportable. They can be trained by one individual in one place, shipped elsewhere, and if the same detection process is used, the rats can work just as well with an unfamiliar person in an unfamiliar location.

Does the African Giant Pouched Rat Make a Good Pet?

You may have decided after reading and watching the videos about the African giant pouched rat that you’d like to own one.

Unlike many pet rats, the African giant pouched rat is not domesticated – it is a captive-bred exotic that maintains many of its wild traits. Some seem to start out friendly and harmless, then later develop aggressive behaviors. It isn’t clear why this happens, but it’s wise to proceed with extreme caution with these animals.

According to the Rat and Mouse Club of America (RMCA), there aren’t many breeders of African giant pouched rats in the U.S. Unfortunately, many people try to return these rats to the breeders once they encounter the wilder aspects of their nature.

No pet should ever be adopted solely for its novelty or because it looked cute in a video. Especially in the case of high-maintenance exotic pets, it’s critically important to understand exactly what to expect so you can make the right decision for both yourself and the animal you’re considering adding to your family.

For a variety of reasons, like so many of the trendy exotics to enter the market, I do not recommend a ‘Hero Rat’ as a pet.

I can, however, wholeheartedly recommend domestic rats. In my experience, they make wonderful ‘pocket pets.’ Tamed rats are generally cleaner, quieter, smarter, more active, playful, and much more sociable than hamsters and gerbils.

If You’re Considering a Pet Rat, Go Domestic

As a general rule, it’s best to leave wild animals in the wild, and domesticated animals at home. Wild animals interpret confinement by or with humans as stressful, whereas animals tamed by humans generally don’t do well in the wild.

Domesticated rats, also known as ‘fancy’ rats, are a much better choice as a pet than a wild rodent like the African giant pouched rat.

Domestic rats are social; wild rats are not. A wild rat will run from you. A fancy rat will not only not run away, he’s as apt to approach you as you are to approach him.

Pet rats are generally the Rattus norvegicus variety – the Norway rat. They are the same breed and species as their wild cousins, but friendlier, much less afraid of humans, and their coat colors have much more variety.

A few facts about pet rats:

  • Norway rats are related to house mice, but are a different species. They live on average two to three years, grow nine to 11 inches in length, with a seven- to nine-inch tail.
  • Male rats are called bucks, females are called does, and baby rats are either pups or kittens. Males tend to be larger and less active than females. Females tend to be more playful.
  • Both genders reach puberty young, at about six to eight weeks of age. It’s important to separate male and female rats before they reach six weeks, though, because they shouldn’t breed this young. Female rats go into heat for about 24 hours every four to five days.
  • Fancy rats are nocturnal, so you can expect yours to be most active at night.
  • They are social and do best if they have at least one other rat to hang out with. Same sex groups are ideal – males usually get along fine if raised together from a young age.
  • Domestic rats have a wide range of coat colors, markings and textures. Some are hairless, others have no tail.
  • Pet rats are not only social, they’re also very curious, intelligent and easily tamed. Like any pet, they require attention and ideally an hour or so each day outside their cages for exercise (supervised, of course).
  • Your rat can learn to respond to her name, and can be taught to sit, stay and other tricks. Rats can also be litter trained quite easily.
  • Contrary to what many people believe about this ‘loathsome species,’ far from being dirty, disease-ridden creatures, domestic rats are actually clean, affectionate, sensitive animals.

Feeding Your Domestic Rat

Similar to the challenge of feeding pet hamsters a balanced diet, if given the opportunity, your pet rat will pick and choose what he wants to eat, which can cause nutritional deficiencies.

Unless your pet eats all the contents of a loose mix prepared diet, it’s best to feed a good quality, low calorie, low-fat pellet or block diet made specifically for domestic rats. Diets designed for gerbils, hamsters or other rodents aren’t a good substitute, as their nutritional requirements are different.

In addition to the store-bought pellet or block diet, you’ll want to feed your rat a wide variety of fresh fruits, veggies and other select people foods to ensure he gets all the nutrients his body needs.

A partial list includes:

  • Fruits like apples, bananas, berries, cherries, grapes, melons, plums
  • Veggies like bok choy, broccoli, carrots, kale, parsley, peas, potatoes, squash
  • Cooked, very lean meats, including liver
  • Whole wheat bread and pasta, brown rice, cooked beans, unsweetened breakfast cereal
  • Yogurt with live cultures
  • On occasion, treats like carob chips, sunflower seeds (high in fat, so feed sparingly), whole nuts in the shell (almonds, Brazil nuts, walnuts)

If you’re interested in a homemade diet for your rat, there are recipes and other resources available online. However, you must ensure that whatever diet you prepare for your pet is nutritionally complete.

Your pet should have constant access to fresh water in a hanging, on-demand bottle. Rats can overheat quickly because they release body heat through their tails only, so in the warmer months or if your rat is housed in a warm location in your house, you might need two or more hanging bottles of fresh water.

How to Safely House a Pet Rat

A large, wire cage is ideal, as your pets (in my opinion you should have at least two because rats need company) need plenty of room, good ventilation, a variety of surfaces to walk on, and lots of climbing opportunities.

Avoid cedar and pine shavings as bedding for your rat. Research has shown the phenols in both cedar and pine can cause respiratory distress and kidney and liver damage in pocket pets. There are many other products available that will be safe bedding for your rat.

Also avoid clay-based and clumping type kitty litter. Neither is safe if inhaled or ingested. Go with a paper-based litter.

Your pet’s cage should be cleaned at least weekly, more often depending on the size, number of animals, etc. A rat cage should have no odor, as rats are very clean pets. A smelly cage is one that is long overdue for a cleaning. Rat urine creates ammonia fumes, which can irritate your pet’s sensitive respiratory system.

If you use a commercial pet cage cleaner, be aware that sometimes the fumes from these products can also cause respiratory issues. I recommend simply warm water and a mild, unscented soap, followed by a thorough rinsing. Never use any household product not designed to clean a pet cage.

Finding a Pet Rat

There are three main sources for domesticated rats – breeders, pet stores, and shelters.

My advice would be to first call your local shelter to see if there are any rats in need of good homes.

My second choice would be rat breeders (ratteries), and finally, reputable pet stores with employees who are knowledgeable about rats, house and feed them appropriately in the store, and handle them regularly. If you’re interested in a female rat, make sure she hasn’t been housed with males or you could be faced with a surprise delivery once you get her home.

Some tips for selecting a healthy rat:

  • She should be in good condition and good health, with a firm, well-rounded body; younger rats are often leaner than adults.
  • His eyes, nose, ears and bottom should be clean with no evidence of discharge.
  • Skin on the ears and tail should be clean and pink; no skin should be red, flakey or have sores.
  • Rats are fastidious groomers, so her coat should be clean and well-maintained.
  • Since respiratory problems are a common rat ailment, you’ll want to make sure his breathing is normal and not labored, and he’s not sneezing.
  • Dental problems can create drooling or wetness around the mouth, so check for a dry mouth area.
  • She should be well-socialized and used to human handling, regardless of her age. Younger rats are more easily socialized than older rats.
  • He should have a good temperament, neither shy nor aggressive -- aggression is especially undesirable and very uncommon in tamed rats.

+ Sources and References