Super Sniffers

Sam Wasser/Center for Conservation Biology/University of Washington

Orca whale scat floating on the water

Eba the dog catches the scent of whale poop nearby. She runs to the side of the speedboat and wags her tail. The crew turns the boat to follow. Eba sniffs the air again. They’re getting closer.

A moment later, Eba gets so excited that she starts wriggling like a fish. Her handler peers over the edge, spots whale poop floating in the water, and nods. The handler tosses Eba her favorite ball, which she catches in her mouth. It’s her reward for a job well done.

Eba is one of the more than 50 dogs that have worked at Conservation Canines over the years. Based at the University of Washington in Seattle, this program trains dogs to use their super sense of smell to help scientists study endangered species, locate invasive plants, identify areas contaminated with pollution, and more.

Eba’s specialty is whale poop. Poop, or “scat” as scientists call it, contains a lot of information about the animal that produced it. Is the animal stressed? What is it eating? Is it eating enough? Scientists can learn all that—and more—from scat. Studying scat allows biologists to learn more about wildlife without capturing the animals.

But finding scat can be difficult for humans. That’s where dogs like Eba come in. Dogs have about 40 times as many smell receptors as humans. Eba can smell whale poop up to half a mile away! “With our work on whales, we estimate that [we get] at least five times more samples from the dogs than what people could get,” says Samuel Wasser, a conservation biologist at the University of Washington.

Eba the dog catches a scent she recognizes. It’s whale poop! And it’s nearby. Eba runs to the side of the boat and wags her tail. The crew turns the boat toward that side. Eba sniffs the air again. They’re getting closer.

A moment later, Eba starts wiggling excitedly. Her handler looks over the edge of the boat. Whale poop is floating in the water! The handler throws Eba her favorite ball. It’s Eba’s reward for a job well done.

Eba works for a program called Conservation Canines. It’s based at the University of Washington in Seattle. Conservation Canines trains dogs to use their noses to help scientists. The pups can sniff out endangered animals, invasive plants, pollution, and more. The program has trained more than 50 dogs over the years.

Eba’s specialty is whale poop. Scientists call it “scat.” Scat can tell scientists a lot about the animal that produced it. Is the animal stressed? What is it eating? Is it eating enough? Scat holds clues to all that—and more. Studying it allows biologists to learn about wild animals without capturing them.

But finding scat in the wild can be difficult. That’s where dogs like Eba come in. Dogs’ sense of smell is about 40 times stronger than ours. Eba can smell whale poop up to half a mile away! Dogs help scientists find at least five times more whale scat samples than people could alone, says Samuel Wasser. He’s a conservation biologist at the University of Washington.

Mark Stone/University of Washington

Eba can sniff out about five times more whale poop than humans can find.

In 1997, Wasser started Conservation Canines. He has spent his career researching wild animals to understand and protect them. After meeting a dog handler who trained hunting dogs to track cougars and wolves, Wasser realized that canines—with their excellent sense of smell—might be helpful for his research, too.

For nearly 30 years, the dogs from Conservation Canines have worked around the world, tracking tigers in Cambodia, caribou in Canada, and more.

But not just any dog can work for Conservation Canines. The dogs have to be extremely high energy, with a strong desire to play. “They typically drive their owners crazy,” says Wasser. “In fact, nearly all the dogs in our program are adopted from shelters.”

To train a dog, the handler has it smell many samples of the target substance. Then the handler sets out multiple containers. One container has the substance inside it. When the dog identifies the correct container, the handler rewards the dog with its favorite ball.

In the field, they repeat the process. The dog is trained to signal when it locates the sample, most often by sitting near it. Then the handler gives the dog the ball as a reward. “There’s a very strong bond between the handler and the dog,” says Wasser.

Wasser’s job is to learn about wild animals and how to protect them. He started Conservation Canines in 1997. He got the idea after meeting someone who had trained hunting dogs to track cougars and wolves. Wasser realized that dogs and their super sense of smell might be able to help him, too.

That was almost 30 years ago. Since then, the dogs from Conservation Canines have worked around the world. They’ve tracked everything from tigers in Cambodia to caribou in Canada.

But not just any dog can work for Conservation Canines. There’s a certain type that does the job best. These dogs have a lot of energy and a strong need to play. “They typically drive their owners crazy,” says Wasser. “In fact, nearly all the dogs in our program are adopted from shelters.”

Human handlers train the dogs to recognize scents like whale scat. First, the handler gives the dog many samples of the scat to smell. Then the handler sets out multiple containers. Only one has the scat inside. The dog has to find the right container. When it does, the handler gives it a prize: its favorite ball!

In the field, they repeat the process. When the dog sniffs out the scent it was trained on, it gives the handler a signal. This usually means sitting near the sample. Then the handler gives the dog the ball. “There’s a very strong bond between the handler and the dog,” says Wasser.

The dogs don’t just track scat. They’ve also been trained to hunt down environmental pollutants, like PCBs. PCBs are harmful chemicals that used to be in everything from electrical equipment to paint. Most humans can’t smell PCBs, but it’s easy for the dogs. Areas where they find PCBs can be cleaned up to keep people—and other animals—safe.

Pups from Conservation Canines have even helped stop crime! Wasser’s team trained dogs to sniff out elephant ivory and other products from endangered species. These products are often imported illegally inside giant shipping containers. The scientists use a vacuum to suck up air from the containers, present it to the dogs, and let them take a whiff. The dogs will immediately let their handlers know whether there are illegal items inside.

The dogs don’t just track scat. They can also find pollution in the environment. One example is PCBs. These harmful chemicals used to be in everything from electrical equipment to paint. Most humans can’t smell them. But it’s easy for dogs! They can locate the chemicals hidden in soil or water. Then people can clean them up.

Pups from Conservation Canines have even helped stop crime! Some of them are trained to sniff out products like elephant ivory. Elephants are endangered, so selling their tusks is illegal. But people sometimes hide them in giant shipping containers to bring them into the U.S. Scientists use a vacuum to suck up air from the containers. Then they give it to the dogs to smell. The dogs can tell right away if there are illegal animal products inside.

Out on the water, whale-tracking dogs like Eba have helped scientists figure out why orca populations are plummeting near Washington State. By examining the whales’ scat, the scientists discovered that the orcas are starving. Populations of king salmon, their natural food source, have been diminished by overfishing and habitat destruction.

After a long day, Eba’s handler takes her home for a good night’s sleep. But first thing the next day, she will be ready to get out on the water to sniff out more whale poop!

Out on the water, dogs like Eba have helped scientists study orca whales. Populations of this animal have been shrinking near Washington State. The whales’ scat showed why: The orcas are starving. Fishing and other human activities have killed off king salmon, their most important food.

After a long day, Eba’s handler takes her home. They both need a good night’s sleep. First thing the next morning, the pup will be ready to sniff out more whale poop!

Write and evaluate expressions based on the Conservation Canines program. Record your work and answers on our answer sheet.

A. Dogs have r scent receptors in their noses. That’s 215 million more than humans. Write an expression to find how many scent receptors humans have in their noses.

B. Evaluate it! Dogs have 220 million scent receptors.

A. The orca whales that Eba helps study need to eat 10 king salmon per day. Write an expression to find out how many salmon they eat in k days.

B. Evaluate it! How many king salmon will an orca eat in 7 days?

A. Most of the dogs in the Conservation Canines program were rescue dogs. About 3.1 million dogs enter U.S. shelters each year. Write an expression to find how many rescue dogs enter U.S. shelters in y years.

B. Evaluate it! How many dogs enter U.S. shelters over 3 years?

A. Dogs can sniff out 5 times more whale scat than humans can find. In one study, dogs from Conservation Canines found w samples of orca whale scat. Write an expression to represent how many samples a human could find.

B. Evaluate it! Dogs found 348 scat samples. Round your answer to the nearest whole number.

A. Scientists wanted to know if wolves in Canada preferred caribou or other big game, like moose and deer. The dogs found wolf scat that showed moose and deer were g percent of the wolves’ total big game diet. Write an expression to find the percent of the wolves’ total big game diet that was caribou.