In South Africa, a Smart Gate Could Help Connect Elephants’ Fragmented Habitat
An unlikely quartet’s clever contraption may allow the pachyderms to make better use of their range
What do a wildlife conservationist, a herd of trained elephants, a jazz composer and an architect have in common? In the South African bush, this unlikely quartet has banded together to develop an artificial intelligence-powered gate and sound system to help the region’s swelling elephant population make better use of its available range.
A two-hour drive north of Johannesburg, in South Africa’s rural Limpopo province, conservationist Sean Hensman runs a tourism enterprise called Adventures with Elephants on a small reserve. Here, Hensman keeps a herd of seven African savanna elephants (Loxodonta africana). These animals have been trained to tolerate tourists, journalists and even the odd scientific project, such as a 2010s-era effort by the U.S. military to develop the elephants’ bomb-sniffing capabilities.
But Hensman and his elephants’ latest project—the A.I.-powered gate—is an attempt to solve a persistent problem plaguing South Africa’s plentiful pachyderms.
In South Africa, all elephants are contained in fenced areas. “To mitigate human-wildlife conflict, we have fencing rules and, as a result, they can’t migrate,” says Hensman, who hails from Zimbabwe and grew up around African wildlife.
Across southern Africa, elephant populations are growing. Based on a 2024 study, the regional population has had small year-over-year growth since 2000 and today sits at around 290,000. South Africa’s elephant population is spread across 94 reserves, 76 of which are on private property or communally owned tribal lands. According to the national environment department, roughly 15,000 square miles—less than 3 percent of the country’s land—is available for the pachyderms.
A general decline in ivory poaching combined with a growing interest in elephant ecotourism and other conservation initiatives have contributed to the population growth. Yet at the same time, the number of private South African game farms or reserves with room to absorb the extra elephants is dwindling. As a result, some have resorted to culling their swelling herds—a drastic measure that requires permission from provincial wildlife authorities.
Key takeaways: South Africa's elephant population
- About 44,000 elephants live in South Africa—more than four times as many as three decades ago.
- This population occupies about 15,000 square miles, which amounts to less than 3 percent of the country. All of the elephants live in fenced in areas across 94 reserves.
“Elephants have to be managed. You can’t keep filling a bottle of water beyond its capacity,” says Ken Maud, a South African game farmer who is also the director of a nonprofit focused on elephant-based ecotourism.
Yet keeping such sizable animals contained—let alone well distributed on the landscape—is no easy feat. “Elephants are breaking out of reserves all the time,” Hensman says.
So on a sultry, overcast day, Hensman, sporting a wide-brimmed hat and green, collared shirt, explains how he sees his new A.I. gate fitting in. Ultimately, he says, the vision is to use the gate to create extended elephant migration routes that cut across South Africa, connecting green areas with navigation corridors that bypass cities and the rehabilitated gold mine dumps that ring Johannesburg.
/https://tf-cmsv2-smithsonianmag-media.s3.amazonaws.com/filer_public/9d/64/9d64c3aa-100c-498e-98d9-337af161f2d7/group-elephant-door.jpg)
growth on private reserves and farms have all played a role. Paco Como/Shutterstock
The gate, which was recently exhibited at the Venice Architecture Biennale in Italy, currently exists only as a proof-of-concept installation at Hensman’s reserve. The gate is equipped with a camera, while a small trailer nearby bears a sound system.
One of the gate’s prominent features is an A.I. image-recognition system to identify individual elephants, which is designed as a security precaution to make sure all animals in a herd are accounted for. The sound system, meanwhile, is used to train the elephants to associate specific sounds coming from the gate with something desirable. In Hensman’s early experiments, he did this by installing the gate in a path on the way to a watering pool, though he says a salt lick would have also worked to lure the elephants.
“We would have the gate open and then slowly play the sound to them—very quietly—so they know it’s positive,” Hensman says.
Putting all of this together, the idea is that if elephant managers install the gate at the border between two game reserves, then, once the elephants have been trained, game reserve owners or managers will be able to use the sounds to coax elephants around the landscape. For example, Hensman says, they could call elephants to a smaller reserve at night and then call them back to their home reserve early the next morning.
With more gates comes more connections. “We can join this property to this property, and we can start to get a flow of elephants … through corridors,” Hensman says.
The challenge of learning to speak elephant—or to approximate it well enough to work, anyway—fell to jazz composer Franco Schoeman. A South African local, Schoeman studied elephant acoustics for his master’s degree in music, and today he specializes in infrasound—the kind of super-low-frequency rumbles below the range of human hearing that are an important component of elephant auditory communication.
“[Hensman] gave me the opportunity to go and record elephants,” Schoeman says, which provided him organic infrasound samples to work with. For the A.I.-gate project, he needed to make unique infrasonic sounds designed to either attract or repel the elephants, which he mixed with higher frequencies so the sounds can be heard by human operators. So far, experiments with Hensman’s trained elephants suggest the animals are willing to follow directions.
“Repelling them is as simple as playing a signal that is harsh or alarm-like,” Schoeman says. “Attracting them is a process of association of what they want to the sound signal. Training can take between a week and a month.”
In previous experiments, Schoeman says, researchers have played a mating call to a male elephant. That gets the bull’s attention, he says, but it also gives the bull the wrong impression. “This is fine for science, but for solutions we need to design a very specific sound which cannot be confused with any existing sounds,” Schoeman says.
The last instrument in the quartet—architect Marc Sherratt—was brought in to make the gate a reality and to help develop the team’s vision of, one day, building extensive navigation corridors that allow elephants better use of their restricted space.
Sherratt, who is based in Johannesburg, has focused his career on a challenging question: How do architects design for nonhuman species? “In the African context, we have cities that are exploding in growth, and our iconic wildlife is getting trapped in these islands,” he says.
In the 1880s, the discovery of the world’s richest gold deposits unleashed an industrial revolution in South Africa that led to the rise of bustling Johannesburg. More than a century later, with our help, elephants could regain the right to roam across at least some of their former range.
This story originally appeared in bioGraphic, an independent magazine about nature and regeneration powered by the California Academy of Sciences.