In Botswana’s Okavango Delta, cattle herds face regular attacks from lions and other predators. Farmers often respond by killing the predators, a practice that has contributed to the steep decline in Africa’s lion population.
In 2015, conservation biologist Neil Jordan proposed a low-cost, non-lethal idea that sounded more like a prank than a serious strategy: painting eyes on the backsides of cows. Over the following years, this unusual method was tested — and produced striking results.
A Simple Idea in a High-Stakes Setting
Neil Jordan, working in Botswana, witnessed local farmers shoot two lionesses after they killed cattle. Looking for an alternative, he recalled how butterflies and certain fish use eye-like patterns to deter predators, and how woodcutters in India wore masks on the backs of their heads to ward off tigers.
He had also observed lions abandon hunts once their prey spotted them. Since lions rely on ambush, he hypothesized that painting fake eyes on cows’ rumps might make lions believe they’d been detected.
The First Experiment
Jordan partnered with the Botswana Predator Conservation Trust and a local farmer for a ten-week pilot study. Out of a herd of 62 cattle, one-third received eye paintings, one-third were marked with crosses, and the rest were left unpainted. Only three cows were killed during the study, and none of them had painted eyes. Every eye-painted cow survived.
Four Years, 14 Herds, Zero Eye-Painted Deaths
Encouraged, Jordan’s team expanded the research. Over four years, they worked with 14 herds totaling 2,061 cattle. Roughly one-third of each herd received eye markings, one-third got crosses, and the remainder were left plain. Out of 835 unpainted cattle, 15 were killed.
Four of the 543 cross-marked cattle were killed. None of the 683 eye-painted cattle were killed. The designs were applied with simple stencils and acrylic paint in black, white, or yellow, chosen for high contrast.
From Experiment to Practice
The project, called the Eye-Cow Project, produced guides in English and Setswana so farmers could use the technique themselves. While researchers noted limitations — such as not testing fully painted herds and possible predator habituation — the results showed clear deterrence.
Published in Communications Biology, this was the first evidence of eyespots deterring large mammalian predators. Today, the technique offers farmers a practical, inexpensive tool to protect both livestock and lions in Botswana.
In Botswana’s Okavango Delta, lions attack cattle so often that farmers shoot predators to protect their herds.
In 2015, conservation biologist Neil Jordan proposed something that sounded absurd: painting eyes on cow rumps.
The results stunned everyone…🧵👇 pic.twitter.com/nmYtq3zvh0
— Fascinating True Stories (@FascinatingTrue) October 6, 2025