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STANDARDS

NGSS: Core Idea: ETS1.B

CCSS: Literacy in Science: 8

TEKS: 6.2E, 7.2E, 8.2E, E.2I, E.3D, E.9E

Watching Their Backs

Scientists investigate whether painting eyes on the backsides of cows helps protect them from predators

BEN YEXLEY/UNIVERSITY OF NEW SOUTH WALES

LOOK OUT! Fake eyes like these were stamped onto the rumps of hundreds of cows as part of an experiment.

AS YOU READ, THINK ABOUT how the needs of people and wildlife may conflict.

People in the African nation of Botswana may have spotted some strange faces peering out from local pastures recently. Looking closer, they’d discover that the “eyes” staring back at them are actually stamped onto the rumps of cows. It’s not a practical joke: The fake eyes were painted on in the name of science.

Large predators such as wolves, lions, and tigers often live near rural communities. That can cause problems for both the wild animals and people. Predators sometimes attack and kill livestock. And farmers and ranchers often retaliate by killing the predators. “Large predators across the globe are in decline, and this conflict between humans and wildlife is one of the big drivers,” says conservation biologist Cameron Radford of the University of New South Wales in Australia.

Radford and his colleagues are seeking ways to help people and animals peacefully coexist. That’s how they found themselves painting eyes on cows’ butts. They hoped to test whether the unnatural markings would deter predators and reduce attacks on cattle.

People in the African nation of Botswana may have spotted something strange recently. Faces are peering out from local pastures. If they look closer, they’ll discover the truth. The staring “eyes” are really stamped onto the rumps of cows. It’s not a practical joke. The fake eyes were painted on in the name of science.

Large predators often live near rural communities. They include wolves, lions, and tigers. This can cause problems for both the wild animals and people. Sometimes, the predators attack and kill livestock. And farmers and ranchers often react by killing the predators. “Large predators across the globe are in decline, and this conflict between humans and wildlife is one of the big drivers,” says Cameron Radford. He’s a conservation biologist at the University of New South Wales in Australia.

Radford and his colleagues are seeking ways to help people and animals live together peacefully. That’s why they painted eyes on cows’ butts. It was a test. Would the strange markings keep predators away and reduce attacks on cattle?

WATCH OUT!

Radford’s team got the idea for the experiment from nature. Many animals have evolved fake eye markings, called eyespots, to protect themselves from predators. “Butterflies have eyespots on their wings,” says Radford. “And they’re found on other animals, like fish and birds.” Sometimes these fake peepers give a species the appearance of a larger or more dangerous animal, like an owl or snake—making a predator think twice about attacking.

In other cases, eyespots may trick a predator into thinking it’s been spotted by its prey. The predator abandons the hunt, believing it’s lost the element of surprise. The scientists wondered if eyespots would fool big ambush predators like lions and leopards in the same way. These hunters use stealth to sneak up on prey. In India and Bangladesh, woodcutters wear Halloween-type masks strapped to the back of their heads to ward off tiger attacks. But no one had ever tried using similar trickery to protect livestock. So Radford’s group decided to test it out.

Radford’s team got the idea for the experiment from nature. Many animals have evolved eyespots. These fake eye markings protect them from predators. “Butterflies have eyespots on their wings,” says Radford. “And they’re found on other animals, like fish and birds.” Sometimes these fake eyes make a species look like a larger or more dangerous animal, like an owl or snake. Then a predator thinks twice about attacking.

In other cases, eyespots may play a different trick. The predator thinks its prey has spotted it. The predator believes the element of surprise is lost, so it stops the hunt. That made the scientists wonder about big ambush predators like lions and leopards. Would eyespots fool them in the same way? These hunters quietly sneak up on prey. In India and Bangladesh, woodcutters need to ward off tiger attacks. So they wear Halloween-type masks strapped to the back of their heads. But no one had ever tried a similar trick to protect livestock. So Radford’s group decided to test it out.

BOBBY-JO PHOTOGRAPHY/UNIVERSITY OF NEW SOUTH WALES

PAINTING PEEPERS: A conservation officer demonstrates the stamping technique.

EYES ON THE PRIZE

The scientists enlisted the help of a rural community in Botswana. In the northwest part of the country, wildlife preserves are home to lions, leopards, hyenas, African wild dogs, and cheetahs. Small farms operate just outside these protected areas. With an assistant fluent in the local language of Setswana, the researchers described their eye-painting plan to locals. “We drove around to farmers and herders, talked about their problems with predators, and asked if they wanted to join,” says Radford.

Farmers in charge of 14 herds totaling 2,061 cows signed on to participate. The scientists got to work. They created eye-shaped foam cut-outs and coated them with paint. Then they stamped large eyes on the rumps of about one-third of each herd. Another third received stamps in the shape of an X. The last third remained unmarked.

At the end of the four-year study, 15 of the unmarked cows had been killed by predators—mainly lions. Hyenas also took down a few, and one cow fell prey to a leopard. Four of the cows marked with X’s were killed. But all the cows marked with eyespots survived. “We were surprised that something as simple as eyes painted on cows’ bums deterred these impressive predators,” says Radford.

The scientists asked a rural community in Botswana to help. The northwest part of the country contains wildlife preserves. Lions, leopards, hyenas, African wild dogs, and cheetahs live there. Small farms operate just outside these protected areas. With an assistant’s help, the researchers told locals about their eye-painting plan. The assistant spoke the local language of Setswana. “We drove around to farmers and herders, talked about their problems with predators, and asked if they wanted to join,” says Radford.

Farmers agreed to help. They had 14 herds totaling 2,061 cows. The scientists got to work. They created eye-shaped foam cut-outs and coated them with paint. Then they stamped large eyes on the rumps of about one-third of each herd. Another third received X-shaped stamps. The last third were unmarked.

The study lasted four years. By then, predators had killed 15 of the unmarked cows. Lions got most of them, hyenas took down a few, and a leopard got one. Four of the cows with X’s were killed. But all the cows with eyespots survived. “We were surprised that something as simple as eyes painted on cows’ bums deterred these impressive predators,” says Radford.

WATERFRAME/ALAMY STOCK PHOTO (FISH); DAVID HAVEL/SHUTTERSTOCK.COM (MOTH)

FAKE EYES IN NATURE: Eyespots appear on the back end of a four-eye butterflyfish (left) and on the wings of an emperor moth (right).

LOOKING AHEAD

The scientists aren’t yet sure what would happen if eyespots were painted on an entire herd for longer time periods. “Predators are good at getting to know their prey, so they might eventually realize it’s a trick,” says Radford.

Other researchers are now testing fake eyes on cattle in Brazil to deter jaguars and in India against leopard attacks. Radford’s team has released a video demonstrating the stamp technique for farmers who want to try it, and a conservation officer in Botswana is spreading the word.

Radford says the study boosts his optimism that people and animals can find ways to share the planet and thrive together: “Sometimes, experiments produce cool results that give us hope.”

What if eyespots were painted on an entire herd for a longer time? The scientists aren’t yet sure what would happen. “Predators are good at getting to know their prey, so they might eventually realize it’s a trick,” says Radford.

Now other researchers are testing fake eyes on cattle. They’re seeing if they can ward off jaguars in Brazil and leopards in India. Radford’s team made a video about the stamp method. They released it for farmers who want to try it. And a conservation officer in Botswana is spreading the word.

Radford says the study is a positive sign. It shows that people and animals can find ways to share the planet and thrive together. “Sometimes, experiments produce cool results that give us hope.” 

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