Poachers and wildlife traffickers go to great lengths to conceal their contraband so they can smuggle it out of a country. They will paint black ivory tusksOr coat them with chocolate and wrap them in a candy bar-like wrapper. They will hide pangolin scales cans of cashew nutsor create containers with false walls and hidden compartments. They will choke their illegal goods smelly materials to try to confuse the sniffer dogs.

But law enforcement officials may soon have a new tool to combat these and other tactics: rats.

Scientists train African giant rats (Cricetomys ansorgei) to detect illegally transported pangolin scales, rhino horns, elephant tusks and African blackwood. These intelligent creatures have not only learned to identify contraband, but they have also figured out how to alert their owners: They use their front legs to shoot at a small ball attached to a custom red neoprene vest that they wear when they work. , which triggers a beep.

Researchers described the skills of these vest-wearing sniffing rodents in a new paper published Tuesday in the journal Frontiers in conservation science.

#HeroRATs against wildlife trafficking!

The giant African pouched rat is the the biggest rat in the worldweighing three pounds on average and extending two to three feet long from nose to tip of tail. Nocturnal rodents live in sub-Saharan Africa and get their name from the pouches they have on their cheeks, which they use to store food. Above all, these rodents have a keen sense of smell and learn quickly.

In the past, scientists from the Tanzania-based nonprofit APOPO trained giant African pouched rats to detect tuberculosisfind landmines and locate earthquake survivors. More recently, the team has focused on combating the illegal wildlife trade.

For the new study, researchers worked with 11 rats named Kirsty, Marty, Attenborough, Irwin, Betty, Teddy, Ivory, Ebony, Desmond, Thoreau and Fossey. Using food as a reward, the team first taught the rodents how to stick their snouts into a hole where they would be exposed to odor samples, a behavior called “nose poking.”

Once the furry participants had mastered this skill, the researchers then began introducing the rats to four commonly smuggled items, as well as items often used to mask the smell of these illicit products.

The target odors were pangolin scales, rhino horns, elephant tusks and African blackwood, a tree often used to make musical instruments. Non-targeted odors were those of coffee beans, laundry detergent or electrical cables. In total, eight of the rats completed training and learned to differentiate between the four target and 146 nontarget odors.

When the scientists tested the rodents five and eight months later, they still remembered the smells they had been taught.

If trained rats become “employed,” so to speak, they could one day help combat a major global problem. THE illegal wildlife trade worth between $7 billion and $23 billion per year, per year. report of the United Nations Environment Program and Interpol. It is now the fourth largest illegal trade industry, behind narcotics, human trafficking and counterfeit goods, according to U.S. Immigration and Customs Enforcement.

“Wildlife is considered a low-risk commodity,” says Crawford Allanwho is vice president of nature crimes and policy advocacy for the World Wide Fund for Nature and has not been involved in sniffer rat research, at CNNIt’s Alex Rodway. “Unfortunately, organized crime knows that there is a real weakness in detection methods at ports, seaports and airports, particularly in Africa.”

Once the sniffing rats mastered their contraband-detecting behaviors in the lab, the researchers took them into the real world for a test run. Last year, they headed to the seaport of Dar es Salaam in Tanzania, a major international trade hub, according to CNN. The rodents were able to find more than 83% of the planted targets, even when the targets were masked by other odors.

African giant rats probably won’t replace sniffer dogs, but they could eventually be used to complement trained dogs. Rats are smaller and more agile than dogs, giving them an advantage when it comes to exploring small nooks and crannies.

“One could imagine detector dogs inspecting large open areas or tracking poachers while rats examine the contents of specific containers or packages,” explains the study co-author. Kate Webbneuroscientist at Duke University, Australian Broadcasting CorporationIt’s Hannah Murphy.

Rats are also cheaper to transport and care for than dogs, and they have no problem working with different human handlers. They also tend to be quick and easy to train, and they live a long time – potentially up to 11 years – so the return on investment is high.

The relatively affordable price of rats is a particularly important advantage, as smugglers often traffic in wildlife products from poorer countries.

“Existing control tools are expensive and time-consuming, and there is an urgent need to increase control of goods,” says the study co-author. Isabelle Szotta behavioral ecologist who trained rats at APOPO but now works at the Okeanos Foundation in Germany, in a statement. “APOPO rats are cost-effective odor detection tools. They can easily access tight spaces like goods in packed shipping containers or be lifted high to filter sealed container ventilation systems.