UPDATE: Sad news – our hero rat Chiku passed away in November 2020 from a large invasive tumor. We will miss her.
They’re fuzzy. They’re cute. They’re smart. Three HeroRATS have arrived at Point Defiance Zoo & Aquarium – the first zoo in North America – and they’re ready to show us how their species save lives.
Celine, Chiku and Mona Lisa are rats, yes – but they’re about as far from domestic rats as Superman is from Clark Kent. African giant pouched rats, they hail from Tanzania. They’re a completely different species from domestic rats – much larger (these three are around 10 inches long, with a 12-inch tail) and with big cheek pouches to carry food, like a hamster.
They also have phenomenal sniffing powers, able to detect both landmines and tuberculosis to save thousands of human lives around the world.
Rats saving lives
Most rodents are incredible sniffers: they have over 1,000 genes devoted to odor detection, compared to 800 in your average dog and just 400 in a human. African giant pouched rats not only have this superpower, but they’re also easy to care for, long-lived at around six to eight years, and highly trainable.
“They’re so smart,” says staff biologist Jessie Sutherland. One of the rats’ caretakers at the Wild Wonders Outdoor Theater, Sutherland first heard about the rats on a podcast, and helped bring them to the Tacoma zoo. “And they’re very food-motivated, which helps.”
As a result, a non-profit called APOPO in Tanzania has been training giant pouched rats – dubbed HeroRATs – to detect unexploded landmines. Too light to set off the mine but willing to sniff for food rewards, the rats are harnessed to a line and systematically search the ground for mines, having been trained to sniff out explosives. When they find a mine, they start scratching, and a trainer marks the area for later removal. A rat can search a tennis-court-sized area in just 30 minutes – something a human would take up to four days to do, depending on how much scrap metal is lying around.
Around 60 of the world’s countries are contaminated with landmines left over from war, and injuries are severe and often fatal. About half of the casualties are children. According to APOPO, the HeroRATs have helped clear over 100,000 landmines, making land safe for people to live, work and play.
The other way the HeroRATs save lives is by detecting tuberculosis, checking 100 sputum samples in just 20 minutes where a lab technician would take days. (A human does confirm each diagnosis.) It’s a lifesaver, literally, for many African communities.
Pouched rats are such good detectors that APOPO is now working on a pilot program to train them to sniff out illegal wildlife products, such as endangered pangolins – one of the most trafficked animals in the world.
Celine, Chiku and Mona aren’t working HeroRATs – to do that work you have to be 100 per cent successful, and some rats just aren’t. (Celine, for instance, loves to dig up the training “mine” and bring it over to her trainers, says Sutherland – not what you want with a real landmine.)
Instead, they’re here as ambassadors – a career change that lets them tell the world about their species and the astounding human-rat partnership that saves so many lives.
But even ambassadors need to keep training – and starting this week, zoo guests can watch them work.
Sutherland and other Wild Wonders staff will set up the rats to give detection demonstrations in a specially-made sand box near the picnic pavilion at Close Encounters.
Training time for HeroRATs
A small pink nose sniffs the air excitedly. Long whiskers quiver.
Finally, tiny pink feet scamper across a box and start to scuffle, digging through sand to expose the treasure – a metal tea ball.
“Good!” says Sutherland, clicking a training device. She whips a peanut out of her pocket and handing it over to Celine, who picks it up in both forepaws and stuffs it into her cheek pockets, shell and all.
“They recognize nutmeg as a smell, so I put that in a little tea-ball infuser and hide it,” explains Sutherland. “When they start digging near the tea-ball I click to tell them that’s the right behavior, then give them a treat.”
And what do scent-detection rats love as treats?
“They’re mostly vegetarian, and they’re very healthy eaters,” Sutherland smiles. “Their favorite treat is banana baby food, which they suck from a syringe, like a straw. But they also love nuts: peanuts, almonds, pecans, which they stick right away into their cheek pouches. They can fit a lot in there – about a golf ball-size in each cheek.”
With baby-pink paws and ears, soft fur that’s gray on top and white on their belly, and a long gray-pink tail that they use for balance, the three pouched rats look a lot alike.
But they have distinct personalities – Celine is super-energetic, while Mona likes back scratches (she makes happy, squeaking sounds) and Chiku is more solitary.
“They’re just such cool animals,” said Sutherland. “They have so much personality. And they help so many people – it’s amazing.”
LEARN MORE: You can read about our new pouched rats’ physical exams here.
APOPO: Learn more about APOPO and their work with HeroRATs here.
SEE THEM: Look out for them at Close Encounters near the picnic pavilion.