In 1965, an emaciated male lion attacked and killed a villager in the Darajani region of Tsavo, Kenya. Locals led American hunter John Perrott to the animal, where he shot and killed it. While admiring his trophy shortly thereafter, Perrott noticed something unusual: a sharp quill jutting out of the lion’s left nostril.
Now, more than 50 years later, researchers have revealed that the quill belonged to a porcupine—and may have been behind the lion’s taste for people. “Every time [the lion] opened his mouth to eat, the damn quill pushed in further,” says Gastone Celesia, a volunteer at the Field Museum and professor emeritus of neurology at Loyola University, both in Chicago, Illinois. Celesia and his colleagues speculate that—starving and with a compromised sense of smell—the lion turned from its standard prey to an easier-to-catch quarry: humans.
This may not be an isolated incident. A number of lion attacks on humans may have been prompted by porcupines injuring the big cats, Celesia and colleagues write this month in the Journal of East African Natural History.
“It’s a very interesting and important study,” says Laurence Frank, project director of the Kenya-based conservation group Living with Lions, who wasn’t involved with the work. “I was actually surprised by the high rate of porcupine killing and eating” by the big cats, he says.
As far back as the 1600s, people have encountered lions injured by porcupines. In 1656 alone, Jan van Riebeeck, commander for the Dutch East India Company, observed two dead lions in Cape Town, South Africa, with porcupine injuries: One, shot after it ate a cow, had numerous quills in its skin; the other, found dead on a beach, had a porcupine quill sticking deep in its chest. Lions don’t often attack porcupines, but they can when prey is scarce or if they are young and inexperienced hunters.
To get a better sense of how often these encounters occur, and what impact they have on humans and other animals, Celesia—along with team leader Julian Kerbis Peterhans, a researcher at the Field Museum, and Thomas Gnoske, an assistant collections manager at the museum—scanned the scientific literature for evidence of porcupine attacks on lions. They also analyzed anecdotes such as van Riebeeck’s, which he recorded in his personal journal. Altogether, the researchers identified approximately 50 lions injured by porcupines, at least five of which went on to attack or kill people or livestock. Young male lions were the most likely to be injured, possibly because they’re inexperienced hunters, the team speculates.
Perrott’s trophy, which was part of the 50, was scanned with computerized tomography at the University of Chicago Pritzker School of Medicine on behalf of the researchers. The scans confirmed that, based on the quill’s proximity to the lion’s frontal sinuses and other key nasal structures, the animal likely had difficulty smelling and had other impairments that would have made it hard to hunt. The researchers also deduced that the lion was approximately 4 years old when it died.
The researchers don’t know how many porcupine-injured lions actually go on to kill people or livestock, but they believe it “greatly increases the risk,” Kerbis Peterhans says. He and his colleagues suspect the wounded lions are more likely to go after people and livestock because the cats are too weak or ill to pursue their typical prey, wildebeest and zebra, which are bigger, faster, and harder to locate. Indeed, at the time of its death, the “Darajani maneater” was “emaciated … with protruding backbone, scapula, ribs, limbs and pelvic carriage,” the researchers report.
One major limitation of the study is that it contains no direct observation of lions being impaled by quills, wrote Craig Packer in an email. Packer, who directs the University of Minnesota’s Lion Research Center in St. Paul, also questioned the finding that young male lions—which tend to be solitary—are more likely to be injured by porcupines. “I’ve seen females remove quills from their pride mates, so it may just be that males are more likely to be seen with quills still stuck in their bodies.”
If porcupines really are causing lions to attack people more frequently, Kerbis Peterhans says it’s critical that injured animals be treated as soon as possible. That won’t just save the big cats, he says, it could help save people as well.