Rats With Custom Vests Are Being Used to Fight Wildlife Trafficking at Ports

You may have seen dogs as part of airport security personnel. But while they sniff out drug smuggling, African giant pouched rats are trained to sniff out illegal wildlife trafficking. In this new study, researchers are using rats’ keen sense of smell to detect scents associated with the illegal trade, such as ivory from elephants and other products from endangered species. Rats have proved themselves capable of sniffing out landmines and pathogens, and now they are protecting fellow animals.

Trained Wildlife Detectors

“Our study shows that we can train African giant pouched rats to detect illegally trafficked wildlife, even when it has been concealed among other substances,” said Dr. Isabelle Szott, a researcher at the Okeanos Foundation and first co-author of the study, in the press release.

Co-author Dr. Kate Webb, an assistant professor at Duke University, stated, “The rats also continued to detect the wildlife targets after not encountering that species for a long period.” These targets were elephant ivory, rhino horns, pangolin scales, and African blackwood trees.

The research took place at APOPO, a non-profit humanitarian organization based in Tanzania. APOPA has developed innovative technology to train rats to detect landmines and tuberculosis. They also train dogs to detect landmines in large spaces of land with lots of vegetation. Wildlife detection follows a similar type of training.

Ratting Out Wildlife Trafficking

The study, published in Frontiers in Conservation Science, involved eleven rats: Attenborough, Betty, Desmond, Ebony, Fossey, Irwin, Ivory, Kirsty, Marty, Teddy, and Thoreau.  Some of the rats were named after conservationists and animal advocates. They completed several stages of training. 

First came the indication training. The scientists placed a target scent in a hole and the rats learned to keep their noses there for several seconds. Whenever they successfully accomplished this task, the rats received flavored rodent pellets.

Then the researchers introduced non-target scents, like coffee beans, electrical wires, and detergent. They chose scents wildlife traffickers often use to mask the smell of their illegal cargo. During this stage, the rats learned to discriminate between the types of scents and to signal only for the target smells. Tests even combined the scents, such as ivory mixed with washing powder, and the rats still detected the item correctly.

Retention training involved testing their memory of the smells. After five to eight months of not encountering certain odors, the researchers would present them to the rats who perfectly remembered whether they were targets or not. The success of this stage indicated that rats’ cognitive retention may be akin to their canine counterparts. As Szott said to Interesting Engineering, “Rats’ performance and learning speed are very similar to that of dogs. Of course, each individual is a bit different. Especially once a rat has learned the ‘basics,’ we can add or re-train them on new scents very rapidly.” 

By the end of the training, eight of the rats were able to identify four common wildlife trafficking targets amidst 146 non-target substances.

Custom Rat Vests

APOPO prides itself on pioneering creative answers to social and environmental issues. Using scent detection animals may be an economical and effective solution to illegal wildlife trafficking. “Existing screening tools are expensive and time intensive and there is an urgent need to increase cargo screening. APOPO’s rats are cost-efficient scent detection tools. They can easily access tight spaces like cargo in packed shipping containers or be lifted up high to screen the ventilation systems of sealed containers,” Szott explained.

However, sniffing is only one part of detection. The researchers state the rats will need ways to navigate shipping ports on their own while being able to alert their handlers. As of now, the scientists plan on outfiting the rodents with vests with a ball on the front that works as a switch.  “Currently, the vest holds a microswitch that emits a beeping sound when the rat pulls at the small ball attached at the chest,” said Szott. The researchers plan to customize the vests with more capabilities, such as a camera.

“The vests are a great example of developing hardware that could be useful across different settings and tasks, including at a shipping port to detect smuggled wildlife,” said Webb.

Beyond Detecting Wildlife Trafficking

APOPO plans to continue to extend the rats’ detection skills. Szott confirmed the organization is researching ways to deploy rats in other situations such as a search-and-rescue during natural disasters. “APOPO’s rats already have been detecting landmines and other unexploded ordnance in former conflict zones for many years,” she said. 

Although this study is promising, it comes with limitations. For one, it took place in a controlled area that did not reflect the environment where illegal wildlife screenings would take place. However, Szott shared that the rats have since excelled at operational trials at the Dar es Salaam seaport.

“Wildlife smuggling is often conducted by individuals engaged in other illegal activities, including human, drug, and arms trafficking. Therefore, deploying rats to combat wildlife trafficking may assist with the global fight against networks that exploit humans and nature,” concluded Webb.